Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: IanJ on September 05, 2017, 05:29:08 pm

Title: Marcher Build
Post by: IanJ on September 05, 2017, 05:29:08 pm
I have started a Marcher steam Engine with the intention of fitting it into a relatively small boat. So far, I have drawings and after encouragement from George (ooyah/2) have completed the crank shaft which I view to be a crucial part. Given a shaft and big-end journal size of 1/4" such an off set gives an overlap that complicates the fabrication of the crankshaft, hence the need to machine from one piece.
The photos shows the sequence that I adopted, I am sure others may have alternative approaches. Photo 1 shows the 3/4" bar faced and centred, then transferred to 'v' blocks to mark out the off-sets of 7/32, 90 deg. apart. Subsequently centres were drilled and the opportunity to mark distances between webs. Before mounting between centres I took the opportunity to remove a lot of material whilst held securely in the 3 jaw chuck before mounting between centres. It was necessary to leave bosses at either end to accommodate the centres. The greatest difficulty was getting cutting tools into and between the  crank webs. Using such small tools means very small cuts and feeds and slow progress! Once the big end journals and web faces are finish the boss at the ends can be removed in conjunction with taking the shaft to its final dia., as the final photos shows. Let's see what other challenges lay ahead and the build continues!


Ian
Title: Re: Marcher Build
Post by: xrad on September 05, 2017, 07:38:38 pm
First, great job. Nice crank.  But it looks like your centering holes are off compared to scribe lines?

How do you mark both ends of rod in exactly the same location for the two offset centering holes(with one end in the chuck)?  If rod was on a flat plate and a line scribed at each end through dead center(parallel to plate)...then roll rod 90 degrees and scribe a second line through dead center at each end...... then another scribe done 'x' distance from center(this time without rolling rod)parallel to plate on both ends...then rolled another 90 degrees and final scribe line done on both ends 'x' distance and parallel to plate... the marks would be pretty close at both ends....


ideas?
Title: Re: Marcher Build
Post by: IanJ on September 05, 2017, 09:33:06 pm
Hi,


I am very pleased with the end result. First all I believe that the camera angle is giving a distorted view of the scribed lines and the centres. Regards scribing the lines; first step face and centre drill the bar at both ends. Remove from lathe and mount and clamp on 'V' blocks resting on surface plate. (1) Scribe line thro centre height at both ends. (2) Set surface gauge to 'off-set distance and scribe a further two line parallel to the first two at each end. (3) Release clamps and rotate 90 deg. with the aid of a square off the surface plate. (4) With the surface gauge at the same setting scribe a further two line at 90  deg. to the others. You now have two off-sets marked at either end same distance from the centre. (4) With the aid of sight glass centre pop the centres and whilst still clamped within the 'V' blocks drill the centres. Given than the centres in the lathe (dead centre, head stock end and Live centre at tail stock end) are in alignment the the shaft will be tuned parallel. Hope this explanation helps with what I did.


Regards


Ian
Title: Re: Marcher Build
Post by: xrad on September 05, 2017, 10:53:58 pm
Thx for reply Ian.  Yes, it is a nice smooth looking crank.  Any need for counterweights while turning?
Title: Re: Marcher Build
Post by: steamboatmodel on September 06, 2017, 03:31:03 am

A very good job on the shaft, I think I would have gone with a fabricated one.
Gerald.
Title: Re: Marcher Build
Post by: IanJ on September 06, 2017, 09:53:57 am
Gerald,


The 1/4" crankshaft and that of the 1/4" big end journals overlap each other which complicates the way a fabricated component.
In the conventional way, the main shaft is left in place until the end of the construction at which time the parts between the webs are removed. However, the main shaft and big ends have already 'broken into' each other. Hope this makes sense. Either way, I had a desire to have go at machining one from solid.


xrad,


No I didn't use balance weights. However, I did reduce the dia. of the main shaft quite considerably, thereby reducing its overall weight which helped any out of balance affects when turning the big ends. It remains a compromise however as if main shaft becomes to slender at an early stage it may flex.


Ian
Title: Re: Marcher Build
Post by: ooyah/2 on September 06, 2017, 11:55:27 am
Gerald,


The 1/4" crankshaft and that of the 1/4" big end journals overlap each other which complicates the way a fabricated component.
In the conventional way, the main shaft is left in place until the end of the construction at which time the parts between the webs are removed. However, the main shaft and big ends have already 'broken into' each other. Hope this makes sense. Either way, I had a desire to have go at machining one from solid.


As Ian has said there is a foul on the crank shaft centres, and to make it as per the drawing it's impossible to fabricate it and that's I why when I made the Marcher shaft I reduced the diameter to7/32" and increased the throw to 7/32" + .010" which allows you to cut thro' the piece of the shaft that isn't required.


George.
Title: Re: Marcher Build
Post by: IanJ on September 14, 2017, 04:48:09 pm
I have done a little more; machined the two eccentrics. I say two, because it is still my aim the make the piston valve version and unlike the slide valve version that employs Stephenson reversing gear that requires two pairs eccentrics (a total of 4), the piston version only needs two. Reversing however, is achieved by a control valve that redirects the steam. I find the control valve rather large and out of proportion to the rest of the engine, so it's my intention to complete the control valve first. If I don't like the look of it I will abandon the idea and build the slide valve version. The size and position of the ports in the cylinder head are slightly different between the two versions, so the decision can be put off until machining of the cylinder head progresses.


The photos show an eccentric set up in the chuck that allows the off-set bore to be drilled and the boss turned. The others are the completed eccentrics. As an alternative to setting up the eccentrics in a 4 jaw chuck and using a DTI to set the off-set, I used the method of using an appropriate size packing piece in a 3 jaw. it is the first time I have used this method and it proved to be very straight forward once you get the packing piece to the correct size. The actual thickness of the packing is proportional to the  off-set and the O/D of the eccentric. I will post the formula that I used for those that are interested. I understand they are a number of variations of the formula all along the same theme, but the end results are so minor they can be discounted for most purposes.
Title: Re: Marcher Build
Post by: steamboatmodel on September 14, 2017, 10:42:03 pm

I wasn't aware there was a formula, I always just sketched it out and tested on scrap until I got it right.
Gerald.
Title: Re: Marcher Build
Post by: IanJ on September 15, 2017, 11:25:53 am
I understand that there are various formulas out there and the "Model Engineers Handbook' (don't have a copy) has one.
[/color]
[/color]The simplest formula is just
[/color]
[/color]Packing = offset x 1.5
[/color]
[/color]For 5mm off-set this would give:
[/color]
[/color]P = 5 x 1.5 = 7.5mm
[/color]
[/color]But the following formula gives a slightly more accurate result whilst not being too complicated.
[/color]
[/color]Packing = 1.5 x offset x (1 - (1/8 x (Offset / Bar Diameter))).
[/color]
[/color]For this example it would give:
[/color]
[/color]Packing = 1.5 x 5 x (1 - (1/8 x (5 / 22))) = 7.29mm
[/color]
[/color]This means that a piece of packing of 7.29mm against one jaw of the 3 jaw chuck should give the required offset of 5mm.
[/color]
[/color]It's best to create a speed sheet, I created simple spread sheet in both imperial and metric that just requires the values to be entered. I am sure there are others who rely on other versions and get satisfactory results.

Title: Re: Marcher Build
Post by: Tug-Kenny RIP on September 15, 2017, 05:08:40 pm

You definitely didn't want colour there then.   {-)

Title: Re: Marcher Build
Post by: IanJ on September 16, 2017, 12:21:10 pm
I cut & pasted the text in from another document, no idea where the 'color' came from!
Title: Re: Marcher Build
Post by: Baldrick on September 16, 2017, 08:25:17 pm
I cut & pasted the text in from another document, no idea where the 'color' came from!


 Probably America , lots of words they can't spell properly.
Title: Re: Marcher Build
Post by: xrad on September 16, 2017, 10:28:14 pm
Probably first from Europe and translated to current HTML format in USA ...... :-))
Title: Re: Marcher Build
Post by: Tug-Kenny RIP on September 17, 2017, 10:01:12 am

Oh , we do like a giggle on here.

Title: Re: Marcher Build
Post by: IanJ on September 23, 2017, 02:30:19 pm
The build continues with the machining of the eccentric straps. A 'stick' of cast gunmetal is provided, the rough bores are oval in shape. However once drilled, split into two by sawing, faced and bolted together the bores become more circular. Mounted in 4 jaw chuck they are then bored out to the finished size of 1/2". I then mounted them on a mandrel and faced both sides almost to finished size. I left a very small spigot on the faces to indicate the final radius/profile to act as filing guide. An operation I carried out whilst still held on the mandrel. Others may prefer to use a rotary table and milling machine. I however find a degree of hand finishing satisfying. Once the outer profile is formed, the mandrel is returned to the lathe and the straps taken to final thickness. The oil pockets and drilling for the connecting rods remains to be done.
Title: Re: Marcher Build
Post by: bfgstew on September 23, 2017, 03:47:11 pm
I do love quality workmanship........... :-))




Stewart
Title: Re: Marcher Build
Post by: xrad on September 23, 2017, 09:41:38 pm
Slitting saw, band saw? What blade thickness?  Thx
Title: Re: Marcher Build
Post by: IanJ on September 24, 2017, 11:38:17 am
Hi xrad,


I drilled clamping holes, then split the casting with a slitting saw of 1/16" thickness. The mating faces were cleaned up in the mill, only requiring a very light cut. Once clamped together ovality of the original casting virtually disappeared. A band saw would have worked just as well, although I don't have one. Equally, careful cutting through by hand always remains an option.


Ian
Title: Re: Marcher Build
Post by: IanJ on September 24, 2017, 03:51:57 pm
Started on the bedplate. Straight forward operation on the milling m/c to achieve the two heights; i.e. overall height and that of the step height of the pads that support the bearing blocks plus a little filling in order to clean up the casting. An alternative method would have been to mount in a 4 jaw and face off in the lathe.
The critical thing is the marking out of various locations/drillings of the bearing blocks and the 4 support columns. These need to be both parallel to and at right angles to the centre line. I achieved this by fixing the bedplate to an angle plate that is ground square. With the aid of surface gauge and surface plate, marked one set of lines, turned the angle plate through 90 deg. then marked out the others.
Title: Re: Marcher Build
Post by: ooyah/2 on September 24, 2017, 07:07:44 pm
Hi Ian,


Very neat and looking good, one thing that I will say about Reeves Castings is that the ones that I have used machine beautifully without blow holes.
I look forward to further progress with your Marcher.
When I made my Marcher I fabricated a base plate from sheet brass with pads soft soldered on and extended the base plate to take an engine driven pump.


George.
Title: Re: Marcher Build
Post by: IanJ on September 25, 2017, 11:52:37 am
Hi George,


I agree, the Reeves castings are pleasure to work with. I suspect that, I too may need to fabricate an alternative baseplate as it may be a better option when fitting it into a boat. In the meantime the present baseplate can act 'test bed'.


Ian
Title: Re: Marcher Build
Post by: IanJ on September 26, 2017, 01:27:47 pm
Next step the main bearings. Housing blocks are cut from ms flat bar, machined square, drilled and bolted together. Bearings are phos bronze machined from hex bar. The drawing calls for 3 no. with no mention that the centre one clearly needs to be split. Did this by soft soldering two halves of hex bar together and machined them in an identical way to the other two, then warming them up to split.
Mounted the housing blocks in 4 jaw, drilled and bored out to suit o/d of bearings. Don't have one of those spring loaded centring things that can be used in the tailstock chuck. But, do have a dead centre with a centre in the rear end. I find if the centre is placed on the centre mark of the component in the 4 jaw and lightly held in-place by the tailstock centre then the run-out can be adjusted (i.e. centred )using a DTI in the convention way. Next thing the fitting of all component onto the bedplate and get the shaft to turn nicely.
Title: Re: Marcher Build
Post by: Mark T on September 26, 2017, 07:23:58 pm
You’re making a really nice job of that Ian and you use the same centring technique that I have always used. I have always found it to be accurate and easy.  Keep the updates coming
Title: Re: Marcher Build
Post by: IanJ on September 27, 2017, 09:05:40 am
Thanks Mark.



Title: Re: Marcher Build
Post by: IanJ on September 27, 2017, 12:02:23 pm
Fixing the bearing blocks onto the baseplate. Drilled a tapped the fixing holes 8BA using the blocks themselves to keep tap square. Also drilled & tapped holes for support columns. Once all blocks & bearings were inlace I used a 1/4" reamer to ensure correct alignment (no photo) as I left the bearing I/D's 1/64 undersize. Final shots shows shaft inlace with other components. Shaft turns nicely, albeit a little tight so therefore needs 'running-in', so oil holes need drilling and oil cups making. Plan to make a start on the con-rods next as that will virtually complete the bottom end.
Title: Re: Marcher Build
Post by: IanJ on October 05, 2017, 04:07:56 pm
The build continues with the big ends & con-rods. Reeves provide a piece of gun-metal for the big end bearings. Once squared off it was marked out, drilled, split face off and fastened together with studs/nuts. Placed in the 4 jaw the bearing was drill and reamed 1/4". Mounted on mandrel the faces were machined.


The con-rod as 'foot' of 5/8" dia. A piece of 5/8" bar was tuned having 5/16" shaft that was to form little end. The 'foot' has 1/8" dia. spigot that helps locate in the bearing.
Title: Re: Marcher Build
Post by: IanJ on October 05, 2017, 04:20:06 pm
Con-rods, are continued;

The 'foot' was drilled and the bearings fixed to it. The rod was returned to the lathe and outer bearing surfaces taken to their finished profile

The excess material of the foot was removed in the mill.
Title: Re: Marcher Build
Post by: IanJ on October 08, 2017, 02:49:18 pm
Con-rods now finished; I opted to cross drill the little end whilst the shaft was still at its 5/16 dia. Back in the lathe the shaft was reduced in dia. & then tapered. The last task was to machine flats on the little end & add bushes. Next, I am going to make a start on the cylinder head, which again is a gun-metal casting.
Title: Re: Marcher Build
Post by: bfgstew on October 08, 2017, 10:58:26 pm
Wonderful example of model engineering.....needs to go in the masterclass section.
Look forward to next update Ian.


Stewart
Title: Re: Marcher Build
Post by: IanJ on October 09, 2017, 06:00:46 pm
Stewart,


Thanks for your kind words


Ian
Title: Re: Marcher Build
Post by: IanJ on October 11, 2017, 02:02:59 pm
My first task in machining the cylinder head was to 'face' the top & bottom in order to provide a surface for marking-out. With regard the height of the casting it has plenty of 'meat' & is well over size. It is necessary however to mark-out heights from the mid-way point to ensure that depths (including the thickness of the column lugs) remain proportional.
When it comes to the locations of the bores & support columns however, the width & length of the casting is a little tight. It took a number of attempts find the centre lines from which to locate the bores & column drillings. Columns locations were drilled & using the same drill, bore pilot holes were drilled.
The head was mounted in the 4 jaw chuck and centred using the pilot hole/dead centre/dti. It was my intention to drill each bore, then bore out. I could also facing off to final depth. On starting the lathe however, the out of balance vibration caused by the combination of the off-centre head and the extended jaw was considerable. A solution would have been to mount the head on a face plate & fit a counter balance weight, but I don't have one. An alternative solution would be to simply drill & ream the bores, they are only 7/16" dia. after all. My equipment is off the small model making type and my bench drill has a max capacity of 3/8' - 10mm. As such I judge it a little under size for the task that would guarantee a need hole.
My solution; back to the mill and use the small boring head I have. A bit slow having to use small cuts & fine feeds, but in the end I would hope to achieve good well aligned bores. I have an adjustable reamer that can be taken to 7/16", so may do the final finishing with that. My next post hopefully will report a successful out come!


Title: Re: Marcher Build
Post by: IanJ on October 13, 2017, 06:26:11 pm
The machining of the cylinder head bores continues; Once the boring head tool was set-up with a suitable degree of side clearance at the tip of the tool both bores machined well. It was little slow, as each "cut" needs to be small, although the "feed" rate can be relatively fast until the final finishing cuts. I estimate that both bores took just under 2 hours to complete which I find acceptable. The set-up was then changed in order to take the support column lugs down to finished thickness.


The support columns themselves are a straight forward turning job. In the absence of having a tail-stock die holder for the small 5 BA die the alternative method of following up with the tail-stock barrel against the die stock was used to ensure square threads. I also 'under-cut' the last thread to ensure that the columns seat correctly onto the bed-plate. The final photo shows a trial fit of the cleaned up head in place. Steam ports & associated drillings remain to be done, although I plan to do the top & bottom head covers a long with both trunks next.
Title: Re: Marcher Build
Post by: ooyah/2 on October 14, 2017, 09:06:26 pm
Hi Ian,


It's always great to get the cylinder up and mounted on it's columns, it seams to give it a bit of life, great job,  well done and look forward to more progress.


George.
Title: Re: Marcher Build
Post by: IanJ on October 15, 2017, 01:03:37 pm
Thanks George,


Very pleased with the end result. I chose the Marcher because of its small size (7/16 bore by 7/16 stroke) as I am looking to but it in relatively small boat. Now that I tried the cylinder head on the columns it's looking a bit bigger than I first envisioned. I may yet (as you have done) swop the bed casting for thiner bed platte. Any suggestion, from any quarter, as to a suitable open launch type hull to match an engine of this size would be most welcome.


I have made start on the top & bottom head covers along with the trunks. As these all have many common diameters & fixing holes I intend to machine them as 'group'
Will post the outcome next.


Ian
Title: Re: Marcher Build
Post by: steamboatmodel on October 15, 2017, 02:53:35 pm

Hi Ian,
Are you looking for a premade hull or plans to build a wood one?
The River Queen makes a nice boat;
http://www.modelengineeringwebsite.com/River_Queen_steam_launch.html
I think the plans are available through Model Boats plans, there was also a smaller version called River Princess.
There are also some on this link;
http://www.selway-fisher.com/Steam.htm
Regards,
Gerald.
Title: Re: Marcher Build
Post by: Jerry C on October 15, 2017, 02:58:27 pm
http://www.floataboat.com.au/ (http://www.floataboat.com.au/)


Have a look at S. L. Wear. It’s similar to Wide-A-Wake.
Jerry.
Title: Re: Marcher Build
Post by: frazer heslop on October 15, 2017, 06:51:24 pm
Very nice work on the Marcher engine
You should be impressed once its running as they have plenty of torque for there size
My only criticism of the engine is that its a heavy little lump when finished. I made the piston valved one and had a lot of problems obtaining a good enough fit.
Been a tight wads my version was made from barstock
Shame you just dipped out on a nice wee boat kit from a fine gentleman from Scotland. Its going to have an MB22 fitted another nice little engine that is ideal for Vic Smeeds River Queen you may find Malcolm's video on utube sorry Iv not got a link
best wishes
frazer

Title: Re: Marcher Build
Post by: ooyah/2 on October 15, 2017, 08:58:32 pm
Ian ,
Here is the link to Malcolm's MB22 engine , thread posted by STEAMUP on this forum  http://www.modelboatmayhem.co.uk/forum/index.php?topic=45093.0




AS you know I have built he Marcher Engine with Stevenson Reverse and I was quite amazed at how heavy it was on completion, I should have used a thinner base plate of 1/32" thk to keep the weight down.
Compared to a TVR engine at 1lb the Marcher engine as I have built it is 2 lbs.


Both engines are very fine runners and difficult to compare performance as I haven't had either of them in a boat for Comparison.


George.


 



Title: Re: Marcher Build
Post by: IanJ on October 16, 2017, 01:26:36 pm
Hi Guys,


Thanks for the information. The River Queen launch is the type I am looking for. I have no desire to build a plank on frame hull as I feel I don't have the skills to do one justice. So, would prefer a moulding of some type that I can fit out.


Regards the weight of the Marcher; I think it is down to the fact that the cylinder head is such a lump in proportion  to the small bores of 7/16". Nevertheless, it's nice looking engine & the first one I have made that predominantly gun-metal/brass & not cast iron. What are peoples view, part paint it or no paint?


Ian
Title: Re: Marcher Build
Post by: steamboatmodel on October 16, 2017, 03:05:14 pm

Something like the Diana Steam Launch would work,
The length overall is 50" and the beam  is 13", it is a bit on the beamy side, but you may want that.
http://www.hartmanmodelboats.com/ (http://www.hartmanmodelboats.com/)
I have an ISIS model from Calder Craft, but it is a closed hull and will probably need a name change before I fit it out.
Gerald.


Title: Re: Marcher Build
Post by: ooyah/2 on October 16, 2017, 04:41:12 pm
Hi Guys,


Thanks for the information. The River Queen launch is the type I am looking for. I have no desire to build a plank on frame hull as I feel I don't have the skills to do one justice. So, would prefer a moulding of some type that I can fit out.


Regards the weight of the Marcher; I think it is down to the fact that the cylinder head is such a lump in proportion  to the small bores of 7/16". Nevertheless, it's nice looking engine & the first one I have made that predominantly gun-metal/brass & not cast iron. What are peoples view, part paint it or no paint?






Ian






Definitely leave it unpainted, it lets others see your excellent workmanship,  I have seen many TVR's painted and in my opinion look terrible.


Only engines with Cast iron frames should be painted.


George.



Title: Re: Marcher Build
Post by: KNO3 on October 16, 2017, 04:53:37 pm
Pin can both enhance and ruin the looks of an engine. It all depends on the quality. Looking at the Marcher, I think the massive cylinder block would look good painted.
Title: Re: Marcher Build
Post by: IanJ on October 17, 2017, 12:11:03 pm
Next the cylinder top & bottom covers. The top covers are simple discs with a bit of detail. The bottom ones have a spigot to accommodate the piston rod stuffing box which is threaded. Identical castings are provided for both types, each having a spigot to mount in the chuck. Without this spigot it would be virtually impossible to turn the top covers as they are so thin. This spigot will be removed latter as it will provide a method of holding when drilling the fixing holes. The stuffing box spigot on the bottom covers do however provide something to get hold of. The trunk guides come as 1 piece. This is a big generous lump of gun-metal, I estimate that 4/5's of it will become swarf in the lathe tray.
Title: Re: Marcher Build
Post by: IanJ on October 17, 2017, 03:30:55 pm
When comes to machining the trunk guides I opted to keep both parts together in order to have something to hold on to whilst removing a fair amount go the waste material. I took both o/d's down to finished size in turn. I then used a parting tool to partially split them into. The parting tool went a good way, I then used a hack saw for the rest. The two now independent halves were faced off to form the flange then drilled & bored almost to finished size. The final bore was then finished with an adjustable reamer to 7/16".


(There used to be a second-hand tool shop within 3/4 hours drive of me here in the West Country. It was a great place full off all manner of both engineering items & wood working tools. It was there that purchased a number of adjustable reamers[at little cost]; I knew they would come in handy one day. It always surprises me that good quality second had tools only command a such a low price. Sadly the place has now shutdown on the riremeont of the owner)


The same reamer, has remained set to 7/16" has been used to finish all of bores. i.e cylinder head & trunk guides.
Title: Re: Marcher Build
Post by: IanJ on October 17, 2017, 04:12:04 pm
Top & bottom covers now complete. The trunk guides were set up in the mill vice using a ground bar to assist with alignment.  A slot drill was then used to cut out the openings. The more observant my notice that one photo shows the trunk guide with the making out lines & the other, with the cutter, without makings. The reason; I completed the machining without taking a photo. So, put the item back into the vice to show the set-up. The other photos show the various item in a rotary vice for the drilling of fixings & subsequent 'spot drilling' of the head.


Next, holes remain to be drilled, tapped, studs fitted & trial fit.
Title: Re: Marcher Build
Post by: steamboatmodel on October 17, 2017, 06:14:41 pm

Nice work Ian, It is amazing how much swarf is generated.
I toured an aircraft plant at one time, I was watching a large CNC Mill that when stopped a guy took a shovel and started removing the swarf. the tour guide said that was there main industry producing Swarf, Aircraft parts were a byproduct. Seeing some of the parts made I believed him, One mill they loaded a 800pd billet on and at the end removed four five pound parts. Keep producing swarf and I am sure you will find a nice engine as a byproduct.
Gerald.

Title: Re: Marcher Build
Post by: derekwarner on October 17, 2017, 09:20:11 pm
Ian...this young machinist uses bronze/brass/gunmetal swarf in an earthenware pot as a bed for the Blueing of carbon steel parts

https://www.youtube.com/watch?v=NsnLVYwqESM

You could consider Blueing the support columns on your Marcher

Derek
Title: Re: Marcher Build
Post by: IanJ on October 18, 2017, 03:45:38 pm
Hi Derek,


Have now decided not to paint over the gun-metal parts and give them a bit more of polish instead. Regards blueing of the MS parts; jury is still out, they also need a bit more of a polish, so see how that goes as first step.


Ian
Title: Re: Marcher Build
Post by: IanJ on October 23, 2017, 02:58:51 pm
The final component of this group is the gland follower, threaded at 1/4" x 40 to match the stuffing box or gland. I then screwed each gland follower into a piece of brass bar with matching thread in order to hold then when drilling the "tommy-bar" holes prior to facing off to finished size.


Also, drilled & tapped the holes in the cylinder head for fixing studs. I always use an odd piece of material faced off & drilled with a clearance hole matching the thread to be cut that acts as guide to aid getting the threads nice & square.
Title: Re: Marcher Build
Post by: IanJ on October 25, 2017, 02:22:22 pm
Now for the piston group; pistons, crossheads & piston rods. Pistons & crossheads are both 7/16" dia in brass. Pistons have 1/8" x 1/8" grove to take the piston seal. I propose to try 1/8 square graphite yarn. Pistons are drilled & tapped 5BA to take the stainless steal rod.
The crossheads are drill & slotted to accommodate the little end of the con-rod & then cross drilled to take the little end pin. I first drill a hole in the lathe then extended the hole to form the opening with a slot drill. The crosshead is also tapped 5BA to connect it to the lower end of the piston rod. The individual components were then tried for fit.


Before moving on to the valve gear I intend to assemble all of the components machined so far in order to achieve good fit &  rotation without tight spots or looseness.
Title: Re: Marcher Build
Post by: bfgstew on October 25, 2017, 02:57:33 pm
QUALITY.


Are you going to polish all machining marks out and Brasso it to within an inch of its life as becomes of these elegant engines?


Stewart
Title: Re: Marcher Build
Post by: derekwarner on October 25, 2017, 11:55:52 pm
Thanks for sharing Ian .....on October 17th you showed and mentioned reaming the Trunk Guide bores to 7/16"

Was this to provide trueness and parallelism, or to provide a desired surface finish?......the reason I ask is you have mentioned the good quality of the 'bronze' castings....and so to intentionally leave a tooling pattern in the bores to aid with retention of lubricity? as opposed to the benefit of a higher surface finish in the cylinder bores

I have also checked the Reeves WEB pages, & couldn't see an all up kit price.....or a listing of material to complete the kit?

Looking forward to the build progressing

Derek   
Title: Re: Marcher Build
Post by: IanJ on October 26, 2017, 03:02:13 pm
Stewart,


Definitely not going to paint. Polishing has begun, easy to start, the difficulty is knowing when to stop!


Derek,


The trunk guides, along with other components, were bored were ever possible using a boring  bar in the lathe. The aim is to achieve concentricity without any tappers as the lathe is best suited for this. Regards the surface finish; the aim is always to try for the finest finish possible by a combination of a suitable tool profile & cutting speed/feed rates. Using the reamer was an additional process that further improve the finish. Many will go that little further (if size & equipment permits) & use spring loaded hones & oils to 'polish' the bore further.
With respect to lubrication; my view, based upon experience with full-size practice going back some 40 years ago was always to look to achieve the finest finish possible, (as mentioned above). Then, ensure that lubrication is delivered to all mating surfaces, either rotating or sliding by the use of Pressurised systems (oil pumps) or Non-pressurised systems such as drip feeders/oil cups etc., or a combination of both. In addition, pipes, drillings/passages are employed to distribute the oil through out the components. In order to ensure that mating surfaces are coated with a film of lubricant, oil-ways are often cut into one of the mating surfaces. I have no experience of ever relying on tooling marks (i.e. poor surface finish) to aid the distribution of lubricant as it would be so difficult to control & predict its effectiveness. An exception is the mating surfaces found on some machine tool slides that, as final operation of hand scrapping the surface is left with a pattern of marks comprising of very, shallow depressions (often referred to as "seagulls") to help with oil retention. But, that aspect of engineering is an altogether different story.
Returning to "model engineering" from "full-size" practice. I am sure there are many skilful people who fit complex lubrication system to their models, Steam Locomotion builders for one. Given the size of the "Marcher" I plan to add oil cups with associated fine drillings were I can & rely upon the frequent use of the oilcan.


Regards Reeves castings:-


On their web-site under "Stationary Engines" you will find reference to the Marcher. There you find various items listed. It is possible to buy just the drawings, the individual castings or a "casing set". No bar material or fixings are listed. Many, as I did will invest in the drawings before committing themselves to purchasing other individual castings or the complete casting set. Some prefer to obtain just a few castings machine other parts from bar stock. Such items are the trunk guides, although I machined them from the castings supplied they could easily be machined from a suitable piece of bar stock. It comes down to personal preference/cost. In my case, I initially purchased the drawings & successfully made the crankshaft at very small cost as I had piece of steel. I then purchased the casting set. Regards the Quality, I have found quality to be very good; no blow holes, hard spots & dimensionally correct.


Hope this answers your questions.


Ian
Title: Re: Marcher Build
Post by: IanJ on October 29, 2017, 12:55:13 pm
All components machined so far have been assembled to check fit. The exception is the fitting of the pistons & rods down through the bore that are then screwed into the crossheads as I yet to make a tool as per George's design.


Prior to assembly I drilled oil passages/pockets in eccentric straps & added oil cups to the main bearings for the supply of oil.
By fitting a drill chuck on to the shaft to gain purchase the engine turns nicely although it's a little tight. However, there are no tight spots. Need to fit the fly wheel & dispense with the chuck, then ensuring it is always oiled just keep tuning it over as you walk past to "run-it-in".


Staring on the piston valve next, considering how best to hold it & the best machining sequence.
Title: Re: Marcher Build
Post by: Jerry C on October 29, 2017, 03:06:48 pm
Keeping it well oiled, run it slowly with the drill. When the oil stops turning black it’s run in.
Jerry.
Title: Re: Marcher Build
Post by: ooyah/2 on October 31, 2017, 09:05:13 pm
`Ian,
 You are making a super job of the Marcher engine and I am glad that you decided not to paint it.
I was reflecting on a Borderer Engine that I made some years ago which was a piston valve and to stop steam leakage at the bottom of the valve box I made a seal which I can't remember how I did it, knowing that you are making your Marcher a piston valve and the dimensions of the valve box is clear I thought that I would suggest a method to stop steam leaks, my engines cylinder block and valve boxes were made from a lump of square cast iron window sash weight
.
So rather than trying to describe my method here is a free hand sketch of a possible way to seal the piston valve bottom.
My Marcher has Stevenson reverse and my drawing doesn't show all the dimensions  for the piston valve so I hope that I am not too far out with my guesses but you could alter to suit your valve rod.
 
George.
Title: Re: Marcher Build
Post by: ooyah/2 on November 01, 2017, 11:43:47 am
Ian,


Just thought on a very simple seal with a bit of graphite packing, a Hex or a knurled nut is all that would be required as it only needs to be finger  tight if there is a small steam leak at the bottom of the valve.


George..
This suggestion means that you don't have to drill down and flat bottom the 1/4" reamed hole and instal an "O" ring
Title: Re: Marcher Build
Post by: IanJ on November 01, 2017, 11:45:14 am
Hi George,


Thanks for the comments & the suggestion of sealing the lower end of the valve. I am continuing with the machining of the piston valve bodies as per the Reeves drawing. The main bore is 1/4" through out its length except for the threaded portion at the top end to take the sealing plug. Your sketch shows a gland arrangement which would require the bottom end of mine to be reworked in someway. You mentioned the difficulties of achieving a seal on such a small piston valve earlier & the possibilities of adding a '0' ring if space & travel of the valve piston/spool permits. At the moment that's the way I am planning to go, although I may substitute the '0' ring for graphite string. I can try various arrangements on the spool without altering the valve body, that way the option of adding a gland as you suggest remains.
I envisage two issues; (1) getting all of the dimensions right that achieves the right "porting' as the drawings call for a 0.005" (0.15mm) overlap. (2) Sealing issues still persist.


The steam passages on both the piston valve body & the matching one in the cylinder head differ to that of the slide valve version. For that reason I have not yet drilled the steam passages in the head, just incase I need to abandon the piston option & revert to the slide valve version. I hope to complete piston valves & get them to stage were I can try them on "live" steam in order to test both function & seal before I commit to adding steam passages to the head. Any views on such an approach?


Ian


Title: Re: Marcher Build
Post by: IanJ on November 01, 2017, 11:50:25 am
Hi George,


Just seen your latest post. I like you alternative arrangement as it avoids the need to put a grove in the piston/spool & allows for adjustment.


Looking to post photos of the work done to date soon.


Ian
Title: Re: Marcher Build
Post by: ooyah/2 on November 01, 2017, 11:54:12 am
Hi Ian,


My alternative suggestion I think is the simple solution and there will be enough metal to thread the bottom 3/8 x 32.
Try it out on steam and see how it goes and if there is a leak you can always reduce and thread the end as there looks to be enough metal to do so.


George.
Title: Re: Marcher Build
Post by: IanJ on November 01, 2017, 01:25:06 pm
The photos show the machining sequence for piston valve bodies. Set up in the 4 jaw chuck & centred around the rough casting the first step was to drill & ream the  1/4"bore. The important dimensions are the face of the valve to the centre of the bore & the location/size of the ports as all other are in "fresh air". I nevertheless decided to clean-up the outside diameters where possible to improve the look & to help with holding.
[/color]
[/color]Using a piece of precision ground bar (that will be subsequently become the pistons), the body was set-up on "V" blocks that allowed the marking out of the various ports etc. from the bores axis. Using this datum it indicated how far out some of the cast lugs can be, although this is not major consequence. This axis was also used to directly measure the distance to the valve face when in the mill. Subsequent photos show the steam passages drilled then plugged. The final photos show cleaned up pair of valves & their associated end caps (not yet sure if the size of hex's look right).
[/color]
[/color]Ports in the valve faces need to drilled & piston made.
Title: Re: Marcher Build
Post by: ooyah/2 on November 02, 2017, 03:05:01 pm
Hi Ian,


I read that you are going to make the Piston Valves from ground steel ,  ground steel is  mild steel, I don't know what grade, and the valves made from this material will rust rapidly so I suggest that you make the valves from St/Steel, once made and installed you can forget about them.


ST/steel from most of the suppliers is usually .0005" undersize so this may account for the leakage at the valve bottom but if you use as suggested with graphite packing it only requires the gland to be finger tight to stop any leaks.


George.
Title: Re: Marcher Build
Post by: IanJ on November 03, 2017, 11:31:16 am
Hi George,


The precision ground steel is: EN1A, free machining mild steel. I am away at the moment, so do not have access to the drawings but I am sure that they did not specify stainless steel. I was intending to feed oil through the engine following a run to prevent rusting, in fact by removing the screwed plugs from the valves you can easily squirt oil in directly. Unlike many other engines having cast iron comments the 'Marcher" has only one internal steel part; the piston valve spool. So the point you make is very valid one.


Although I have made 1 spool already, which appears to function well, I can easily make additional ones out of stainless steel, once I get some.


Ian
Title: Re: Marcher Build
Post by: IanJ on November 13, 2017, 12:30:10 pm
The "Marcher" drawings do not specify the material for the valve spool. Interestingly, the drawings for "Borderer", which is virtually a bigger version of the "Marcher" does however specify stainless steel. George is correct, stainless is the way to go, there is no value in making them out of anything else.
I have completed the valve bodies by drilling the ports. As the dimensions are critical I used a DTI in order to get the spacings right.
I went on to complete one set of the connecting rods/adjusting yokes. With a valve body and connecting rod components set-up with a gap between it and the cylinder head I intend to try it on "live steam" not only to check its function but more importantly see how good or bad seal is before I try seal options.


On a more general note. The "Marcher" is quite a small engine, which is its appeal, however it's also very heavy for its size. I estimate it will come in at some 840g. Of that, the fly-wheel is 185g. That's over 20% of the total weight. In my mind that's lot of mass revolving on what is small shaft of 1/4". I have Stuart Compound Twin; bores of:- 1-1/4" & 3/4" and its fly wheel is only 1g. heavier than that of the "Marcher"l. Any observations would be most welcome.
Title: Re: Marcher Build
Post by: frazer heslop on November 13, 2017, 02:05:51 pm
Hi Ian, once she has freed up simply do away with the flywheel
I ran my engine with no flywheel fitted in a Thames style launch with no ill effect on performance . I think it was more responsive
cheers
Title: Re: Marcher Build
Post by: ooyah/2 on November 13, 2017, 05:04:32 pm
Hi Ian,


Very neat work and the engine is coming along fine.


What is the reason for the spacers between the Cylinder block and the piston valve casting ?


Regarding the Marcher's weight mine comes in at 2 lbs including the boiler feed pump and I agree that it's a heavy little beast but like you I really like it.


The flywheel on mine is 1. 325" dia with the centre heavily milled out  , another attempt to keep the weight down, had I known the eventual weight outcome I would have made the base plate in Ali rather than 10 SWG brass. but it's a fine little runner.


George.
Title: Re: Marcher Build
Post by: IanJ on November 13, 2017, 06:20:26 pm
Hi George,


I have not yet drilled the corresponding steam passages in the cylinder head that match the piston valve. The steam passages are located at different centres depending on the type of valve body chosen. I thought if I packed the valve body a little distance from the cylinder head it would allow steam to flow whilst still maintaining the relationship with the eccentric etc for testing . If I can not achieve a seal on the piston valve, I will abandon the idea & build the slide valve version and commit to adding steam passages to the head. It will mean machining alternative eccentrics & linkages etc but as you have pointed out before steam leakages will not be an issue. I will of course, also need to add reversing gear.


Regards the weight, I am also planning to loose some more mass from the fly wheel, but it still seems heavy in proportional terms to the engine.


Frazer, you make an interesting point re value of fly wheels at all. I suppose a coupling disc is the minimum that is needed and a selection of discs can easily made for trials.
Title: Re: Marcher Build
Post by: frazer heslop on November 13, 2017, 09:36:31 pm
Hi Ian, dont forget the prop should and I believe does give some flywheel effect
The Mb22 has no flywheel although it has some larger webs in the crank design
Good luck with the piston valves for some reason they gave me a lot of grief getting a running fit without leakage.
cheers
Title: Re: Marcher Build
Post by: IanJ on November 14, 2017, 07:25:45 pm
One of the piston valves now tested with live steam. Steam (or a lot of water vapour) issued forth from the ports as the engine was turned over and condensed on the various parts. There was however, no leaks from the bottom of the spool.


Not sure what it proved as the valve body was set a little distance from the cylinder head & the steam could easily flow through the valve, so it must be assumed there was not much pressure within the valve body. I intend to repeat the test with the valve body fitted to the cylinder head and see what degree of leakage there is then.
 
Title: Re: Marcher Build
Post by: IanJ on January 25, 2018, 05:51:16 pm
Having been away, then Christmas, plus other distractions its been some time since I last posted on Marcher Build. Following Georges advice regards using stainless steel for the valve spools I ordered various diameters. Whilst waiting for delivery I made up a piston fitting tool (again thanks to George) to assist with the assembly of the engine & subsequent maintenance operations.


On the piston valve version reversing is achieved byway of 4 port valve i.e. : Steam. in/out & forward/reverse. The valve body is in two parts, between them is a valve disc mounted on a spindle. Again, with the stainless steel still a day away I made a start on the valve.


Two things then occurred that has prompted me to abandon the piston valve version and instead make the slide valve version with Stevenson reversing gear:-


(1) I feel that the completed reversing valve will be just to big in relation to the engine and will lack elegance alongside the engine, see photo of valve alongside that of the cylinder head. Also, it's heavy and adds more weight to what is already heavy little engine.


&


(2) I snapped off a HSS drill in one of the valve ports that is well and truly embedded resulting in ruined component.


Work will now commence on the side valve version. I now need a further two more eccentric straps, four new eccentrics as the 'throw' is different to that of the side valve engine. I will now need some form of throttle valve, but this can be more elegant and I feel more in keeping the with the size of the engine.


Ian
Title: Re: Marcher Build
Post by: Moxis on January 26, 2018, 06:51:25 am
Very interesting build blog indeed Ian. When thinking what to build next, I have considered a lot about this Marcher engine and some nice wooden open sloop project.
But in the beginning you said that your engine is intended to power a relatively small boat. Could you explain, what would be the correct size of the boat which would suit Marcher engine? And how big boiler would be needed to supply the Marcher? I am not very keen to fabricate the boiler too because I lack the eguipment & skills to do proper silver soldering, so my intention is to purchase it from a suitable source and that's why I am asking.
Title: Re: Marcher Build
Post by: IanJ on January 26, 2018, 01:52:52 pm
Hi Moxis,


I feel that there are many others that are better qualified to comment on engine/boiler/hull size combination. Nevertheless, my view is that although the Marcher is relatively heavy for its size the bores are only 7/16" (12mm) diameter. So I believe that the steam consumption will not be that great and that a boiler of 3 1/2" (90mm) diameter would be suitable. In fact, a 2 1/2" (65mm) may do. I also do not have the desire, skill or the equipment to make a boiler so will purchase one when the time comes. Boilers made by Pendle  Steam have a good reputation as testified by many contributors to this forum.


Regards the hull size; I am looking at an open hull of something less than 900mm.


I would welcome the views of others.


Regards


Ian
Title: Re: Marcher Build
Post by: rhavrane on January 26, 2018, 05:58:09 pm
Bonjour Ian,
A friend has ordered a 4,5" horizontal boiler for a D10 and I have ordered a Kingdon one to Nigel (Pendlesteam). They will arrive soon. I will be happy to share our experience with you. First feeling, Nigel is really listening to his customers, he has made special adjustements for my requirements, he gives pictures of his progress and his prices are "reasonable", despite a pound high compared to €uro. 
Title: Re: Marcher Build
Post by: IanJ on January 26, 2018, 06:28:58 pm
Hi Raphael,


Look forward to hearing about your experience of your new boilers.


ian
Title: Re: Marcher Build
Post by: ooyah/2 on January 26, 2018, 10:17:35 pm
Hi Ian,


Glad to hear that you are now going for Stevenson reverse gear which in my opinion is by far the better, you don't have any problems with steam leakage at the valves, the only thing that I like about the piston valve is the ease of forward and reverse but the castings are a bit on the heavy side for the Marcher engine.
The throttle valve is also a bit bulky for the marcher so I am posting a pic of a throttle valve that I made for a TVR engine and it works very well, try and get the lubricator before the throttle valve to carry some oil into the valve for lubrication.


Keep up the good work.


George.
Title: Re: Marcher Build
Post by: IanJ on January 27, 2018, 12:01:35 pm
Hi George,


From the outset the fall back position was to make the slide valve version, hence not drilling the steam passages in the cylinder head until I was certain the piston valves would be suitable, or as certain as I could be.
If I had not been waiting for the stainless steal and had not made a start on the two-way valve I fear that I would have gone the wrong way.
A throttle valve of the type you suggest possibly incorporating a lubricator is more in keeping with the size of the Marcher and I feel much more elegant than that bulky and heavy two-way valve which may suit a bigger piston valve engine but not the Marcher as it's simply out of proportion.


Already made a start on the valve chests and will post progress presently. Planning to utilise a "grub" on the valve spindle to aid adjustment and not make the screwed version.


Cheers


Ian
Title: Re: Marcher Build
Post by: IanJ on January 30, 2018, 07:05:23 pm
The slide valve comprises of; valve chest & covers, both are casting. The spindle top guide & gland follower will be machined from brass as will the valve itself.


The valve chests were first squared up in the mill to aid marking out and holding in the 4 jaw the faces then taken to almost finished size.



The drawing shows the gland follower to flanged type pulled up on nuts on studs. Given that the spindle guide is made up from brass hex bar I have elected to make the gland follower also out of brass hex bar. To that end I have machined spigot on valve chest that will form the glands stuffing box that will be screwed to take the screwed gland follower.
Title: Re: Marcher Build
Post by: ooyah/2 on January 30, 2018, 11:47:02 pm
Ian,
Are you sure that by making the gland stuffing box as you describe that there is enough clearance between the hex gland and the fork at the bottom of the valve spindle when the eccentric is at its  T.D.C.


I made mine as per the drawing and found that the clearance was only 3/32".  ( see pic )


George.
Title: Re: Marcher Build
Post by: IanJ on January 31, 2018, 01:08:23 pm
Hi George,

Simple answer is; no I did't consider the clearance.

I have since had a look at the drawings & I believe that if I keep the length of the spigot to that of the stuffing box as drawn & keep the size of the hex head to that of the gland follower also as drawn I should get away it. The nut will be very thin though.

I have since drilled & tapped both valve chests to take the spindle guides & gland nuts, that hopefully will not foul. Have also machined valve chest covers. 1st. by facing off what will become the outside face but leaving a snub piece to hold in the chuck that allows the inside face to be faced off. Holding it by the snub piece is the only way to achieve the finished thickness of 3/32 (2mm). The alternative would be to use sheet material, although I don't have any. Nevertheless, I feel the overall effect is more pleasing if GM is used throughout.

The final photo shows one of the chests, with its cover in place taken down to finished size.
Title: Re: Marcher Build
Post by: IanJ on February 01, 2018, 02:48:24 pm
Valve chests, covers, spindle guides & gland nuts now completed. Also made start on the slide valve by milling out the square recess in the face. The drawing shows it to be 3/16 square, with no radius in the corners? I used a 3mm slot drill which as left 1.5mm radius in the corners. The next operation is to mark out & drill/mill the steam passages in the cylinder head. I will then assess the slide valve in its present form before I attempt to get into the corners with a smaller mill. I do have 1mm somewhere that came as part of set.


Sorry for the lack of actual machining photos, but my iPhone batteries went dead.


PS Don't know how others take & post photos; I now do not use my camera, I now use my iPhone, I use "file share" option to get them into a dedicated file, resize them to 800x600 pixels & then attach them.
Title: Re: Marcher Build
Post by: southsteyne2 on February 01, 2018, 10:36:22 pm
Hi Mark don't worry about the corners of the valve , just make sure it is flat against the face
Cheers
John
Title: Re: Marcher Build
Post by: ooyah/2 on February 02, 2018, 11:11:43 am
Ian,


The radiuses corners are not so important, if you have a 1/16" slot drill just go into the corners with that , or if you can find your 1 mm slot drill use that, as John says make sure that the valve is flat on the cylinder face.
I tried unsuccessfully to find a supplier with a 1/32" slot drill with no success so the 1/16" one sufficed, it's the same with the ports on the cylinder block, I used my 1/16" slot drill and the engine runs well.


George.
Title: Re: Marcher Build
Post by: rhavrane on February 03, 2018, 06:50:21 pm
Bonjour,
Sorry, not in the appropriate topic, but I started here.

I could not wait to share with you my Kingdon boiler : https://youtu.be/5heUAKoZEW0
And a few pictures here with its future launch : https://goo.gl/photos/tNdsxUQ7eQRApcH89 (https://goo.gl/photos/tNdsxUQ7eQRApcH89)
Title: Re: Marcher Build
Post by: IanJ on February 03, 2018, 07:19:17 pm

It I have made a start on the steam passages in the head. After marking out I search out my 1mm slot drill,  I nevertheless chain drilled the ports before using the mill. I found that the mill performed very well and chain drilling was unnecessary. Recesses in the bores were then cut. I made up piece of wood scaled off the drawing to support the head at the correct angle when drilling the steam passages. I have found that the inlet ports are little shallow and need to be taken a little deeper.

It was then that broke my 1mm end mill, not in use but when snagged on the edge of something. I have the little Proxxon milling machine to be great little tool fine work. The available cutters are; 3, 2, & 1mm They are quite robust in use, but can snap if knocked.


So, need to send for a replacement cutter which will come in a few days. However, Axminster Tools who are the main dealer/importer for Proxxon is 30/40min drive for me, so may have ride out next week. A visit can prove to be fatal as their show room is full of all sorts of delightful items!
Title: Re: Marcher Build
Post by: IanJ on February 12, 2018, 11:32:38 am
Got a new 1mm cutter (slot drill) from Axminster Tools & completed steam passages.


Have also completed the valve chests & slide valve. The slide valve version requires; 4 eccentrics, straps & rods which are different to pair that I made when planning to make the piston valve version. The throw of the eccentric is different to that of the piston valve. The machining method remains the same i.e. using suitable size packing in the 3 jaw. The rods are also to a different pattern and machined from a solid piece of square bar.
Title: Re: Marcher Build
Post by: SteamboatPhil on February 12, 2018, 12:12:56 pm
This is really coming along well, really nice job.  :-))
Title: Re: Marcher Build
Post by: IanJ on February 23, 2018, 12:14:41 pm
The work continues on the link rods, albeit slowly due to a cold workshop (i.e. one end of my garage) & tummy bug. The two are not related, as grandson came home from nursery & shared his newly acquired condition with the whole family!


The ends of the link rods once taken to size were slotted & cross drilled. I do whatever I can & that I feel appropriate by machine tool, I do however, like to do the finishing such as forming the radius by hand.


The eccentric straps/rods need to be assembled & get a bit of a polish. The crucial aspect is setting the length, so may make a simple jig to assist with this.
But first, I intend to make the two expansion links out of 1/8" ms plate. Two ways to do this; (1) All by hand, mark-out, drill pivot holes, chain drill slot & file to shape. (2) Machine, mark-out, set-up on rotary table, drill pivot holes, mill slot/profile, then finish by hand.


If mill/rotary table is not available, then the decision is made for you. I do have small mill & as yet an unused rotary table. So it's option (2), just need to decide the best set-up.
Title: Re: Marcher Build
Post by: Mark T on February 23, 2018, 04:29:36 pm
You've made a lovely job there Ian and I really like the way that you have finished the radiuses by hand.  I remember as an apprentice having to use radius gauges with a file and being sent back to the vice time and time again until I got it right.  I think that its a skill that once you have mastered it; it will stay with you for life and you have done a very nice job there.
Title: Re: Marcher Build
Post by: IanJ on February 23, 2018, 06:24:06 pm
Thanks Mark,


One way of helping to form a radius on such items is to use a nut & bolt with suitable sizes washers. If left a little loose the file causes the washers to "skid" around as radius comes to size. Personally, I prefer to finish such small items by eye, if it looks right it's very often right. As you & many will know components that need to fit/mate to each other are another matter & need to be as close to the given tolerance as equipment & skills permit.


Many years ago, I also spent the first months of my apprenticeship learning bench skills. The process used to pass on & master such skills is well established; Explain, demonstrate, imitate, practice. It was the practice element that took the time. Why do I suspect that the so called "Modern Apprenticeships" (a term that I hate) lacks in "practice" time. I'll now step down from my soap box!


I have been away from the practical side for a long time & now that I have recently taken up model making I find that it is the the practise bit that needs further work.
Title: Re: Marcher Build
Post by: steamboatmodel on February 24, 2018, 02:16:48 am

Great build. We referred to Washers as "Poor Man's Buttons"  Forman and tool crib had proper hardened button sets, but unless the job required it we used washers.
Gerald.
Title: Re: Marcher Build
Post by: IanJ on February 24, 2018, 02:05:02 pm
Gerald, thanks for your comments.


Another device that is often used is the filling rest on the lathe. Comprising of two parallel rollers mounted on a bracket that can be raised on jacking screws so that it embraces the stationary workpiece/shaft. When set at the right height and with the file guided & resting & on the rollers flats can be formed on the shaft. If the lathe spindle has an indexing facility, squares, hexagons,etc. can be produced.


I have never used one, but I am sure there must be others out there that have experience of such tools.


A tool that I would like to obtain is a filling machine; bit like a scroll saw, but having a reciprocating file instead of a saw blade. Never seen one, let alone used one, although I understand them to quite small using 6" long files. Can see how useful they could be in forming profiles. Again others may experience of such things.
Title: Re: Marcher Build
Post by: derekwarner on February 24, 2018, 08:40:28 pm
Re : Filing Machine

Ian...........I have seen this young chap Chris from Clickspring use his base mounted reciprocating Filing Machine..........

I also find his work very interesting ........

Derek


www.youtube.com/channel/UCworsKCR-Sx6R6-BnIjS2MA
Title: Re: Marcher Build
Post by: IanJ on February 26, 2018, 07:51:02 pm
The Expansion Links are now completed.


I mentioned two ways to produce the expansion links; all by hand, chain drilling & filing, or machining. In the end, I used combination of the two.
From the centre point of a piece of 1/8" ms plate I marked out the two expansion links & mounted them on the rotary table employing a central spigot thus locating the plate centrally on the table. I could of put one on top of the other and machined both together, that however would result in a combined depth of 1/4' which in my view is a little deep for a 1/8" end mill.
Ist. operation was to machine the outer radius followed by the slot. Then the pivot points were drilled. I could not then see any advantage in continuing with the mill, so the plate was removed. A hacksaw produced two blanks that were bolted together, the inside profile was done by hand. The filing takes as long as it takes, but I find it quite satisfying. The final photo shows the links fitted with the bearing bushes. I estimate total time for both expansion links to be around 8 hours. Without the mill the slot could be easily produced by chain drilling and file(s).
Title: Re: Marcher Build
Post by: IanJ on March 14, 2018, 03:21:28 pm
The making of the reversing gear continues with the associated drag links, weight shaft arms, anchor link & weight shaft brackets. The drag links & anchor link are simple pieces of flat bar, drilled then fitted with bushes. One way to make the weight shaft arms is to machine them out of solid either in the lathe or on the mill using a rotary table. I decided to make them up from flat bar & bushes in a similar way to that of the drag links. The weight shaft brackets were formed from bending brass strip, drilling the appropriate holes & fitting with bushes. The operating arm remains to be done. The next step will be a final clean up & assembly to check fit.


These little components, although simple, are taking sometime to make. You cannot compromise on their accuracy as it is crucial for the correct function of the reverse gear.  Not shown are the discarded ones were the drilled holes were "just a little off" & at this size, "just a little off" looks appalling! Almost at a point were assembly of engine proper can begin.
Title: Re: Marcher Build
Post by: ooyah/2 on March 14, 2018, 10:33:20 pm
Hi Ian,
Very neat, I made all the reverse parts in Brass for the long term future as I have seen some Stevenson reverse linkage made in M/Steel and beginning to rust, I suppose it's all a matter of choice, I look forward to you getting things together, it's a neat little engine.


George.
Title: Re: Marcher Build
Post by: IanJ on March 15, 2018, 01:24:10 pm
Hi George, as always thanks for your observations.


I used mild steel for two reasons; (1) it was specified on the drawings & more importantly, (2) I had various bits of mild steel to hand.
Clearly in use, the linkages, along with all other parts are going to be kept well lubricated. I assume it's corrosion during the subsequent storage time between runs that you are referring to. If the engine is cleaned, well oiled & stored in dry environment I hope to be ok. Unlike other engines with cast iron cylinders/valve chests etc., engines such as the "Borderer" & "Marcher" are predominately gun-metal with only some external parts out of steel that can be easily checked upon. I hope this will be the case, time will tell.


Cheers


Ian




Title: Re: Marcher Build
Post by: Moxis on June 13, 2018, 06:20:02 am
Long time has elapsed after the last updating of this build. I wonder if everything is fine and Marcher is running nicely? I am asking this because am pondering the purchase of the set of castings & starting a similar project.
Title: Re: Marcher Build
Post by: IanJ on June 13, 2018, 07:11:44 pm
Hi Moxis,


You are right it has been sometime since I posted progress on the Marcher Build. I have been some what distracted due to another project taking priority. I have only been the Project Engineer. The Project Sponsor (my good lady) & the Project Manager (Grandson) have being  setting the priorities!


The project that I refer to the building of a "Toylander", a scaled down Series 2 Land Rover. There are nevertheless, similarities with boat building; the body (hull) is moisture resistance MDF, propulsion is two mobility scooter motors powered by two 12 volt batteries. No navigation lights as such, but it has got working headlights, side lights & indicators. its now completed, other than painting the wheels.


I can now resume with the Marcher build which is at stage as per my last post.


Regards


Ian
Title: Re: Marcher Build
Post by: Moxis on June 13, 2018, 07:28:54 pm
Thanks Ian for your reply. In fact I had also drawings for Toylander, but didn't ever build it. And years went by & grandchildren grew up so fast that they wouldn't fit any more into the small car, so I sold the plans.

So now I wait eagerly that you will complete your Marcher build and we can see how nicely and smoothly it is running.