Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: tugsmoke on December 16, 2011, 02:52:21 pm
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Hi everyone
I am interested in building a tug from a kit such as the Mountfleet Cruiser or single screw version of the Caldercraft Imara and fitting it with live steam power plant. I intend to build the steam plant with a twin cylinder slide valve engine and obviously it is important to ensure that the steam plant is correctly matched to the model. I am looking for advice with regard to suitable engine size (bore x stroke) and matching boiler, ideally with some reference to available designs. Can anyone help?
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Anything less than a Stuart D10 size is going to be found wanting. Are you proposing to make your own plant?
Regards Ian.
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Hi Circlip. Thanks for your post. Yes I do intend to build the steam plant. I am new to model boats and have never built a serious steam plant so I am on a steep learning curve but I like a challenge. I have been doing some research and have found some rule of thumb formulae which purport to determine a suitable engine swept volume from the overall dimensions of the hull which I guess also relates to the model's displacement. Both the the Imara and the Cruiser come out at about 40lb. The results for the three sources used vary quite a lot but the average would suggest a swept volume in the 0.7 to 0.8 cu ins region. If I have the correct information a Stuart double 10 is 3/4 ins bore and stroke which gives a swept volume of about 1.33 cu ins. which would suggest it's a bit on the big side. I am thus somewhat confused. Of course these formulae may not be worth much and your comment may well be based on practical experience which is always the proof of the pudding so to speak. Could you please enlighten the confussed. {:-{ I am on holiday for the next week so will read you later.
Tugsmoke
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OK., re - building your own, check your E-Mail. Two pieces of required reading are KNH's two reference works.
Both vessels you have mentioned are tugs, which have the hydrodynamic finesse of an elephant. Had you been going for a pinnace, the plant would have been smaller due to the finer lines. There's no substitute for power.
Regards Ian.
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Hi Circlip. Thanks for your post. Yes I do intend to build the steam plant. I am new to model boats and have never built a serious steam plant so I am on a steep learning curve but I like a challenge. I have been doing some research and have found some rule of thumb formulae which purport to determine a suitable engine swept volume from the overall dimensions of the hull which I guess also relates to the model's displacement. Both the the Imara and the Cruiser come out at about 40lb. The results for the three sources used vary quite a lot but the average would suggest a swept volume in the 0.7 to 0.8 cu ins region. If I have the correct information a Stuart double 10 is 3/4 ins bore and stroke which gives a swept volume of about 1.33 cu ins. which would suggest it's a bit on the big side. I am thus somewhat confused. Of course these formulae may not be worth much and your comment may well be based on practical experience which is always the proof of the pudding so to speak. Could you please enlighten the confussed. {:-{ I am on holiday for the next week so will read you later.
Tugsmoke
As Ian says there is no substitute for power and a must for reference is the K.N.HARRIS books on engines and boilers for the amateur engineer.
If you are considering CRUISER or IMARA the D10 will be the engine that you will need.
At 40lbs it's a big blunt nosed boat and I hope that you are fit enough to lug it about.
I have posted details of my steam tug CERVIA which is 3/8" scale 42 " long and weighs 32 lbs, my posting shows it with a 10V engine which had more than enough power but had the old problem of stopping and starting so it now has a D10 with an engine driven pump to a 4.75" dia Scotch return flue boiler and I have to screw down the throttle valve otherwise she would drive her self under, she runs well on 30 P.S.I
( S.T. CERVIA an old Lady ooyah/2 5 802 Last post November 11, 2010, 05:47:15 PM )
this is my posting just scroll down the page.
I don't know where you got the figure of 1.33 cub" as it's nearer to .99 cub" not including a steam space top and bottom of the cylinder.
As the cylinder is 1.125" thro" the bore the swept volume is, area of the bore x length of cylinder bore 1.125" x 2 = .99 cub "
So in my opinion which ever vessel you chose the D10 is the engine to use and it's not so difficult an engine to build but a great workhorse.
I hope that this will help you.
George.
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If the D10 is 3/4" bore and stroke the displacement, ignoring the piston rod, is 1.33cu in. The length of the bore is not relevant to this calculation.
I steam my 1/19 scale TID (45" long) with a 1/2" bore x 5/8" stroke Borderer twin (.49 cu in) piston valve engine. Cheddar claimed that one of their Puffin plants was adequate for the Imara, a bit suprising perhaps.
Just suggesting that the D10 may not be the only option.
Regards
Keith
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And ETW's Warrior twin. 3/4" bore x 5/8" stroke.
Regards Ian.
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If the D10 is 3/4" bore and stroke the displacement, ignoring the piston rod, is 1.33cu in. The length of the bore is not relevant to this calculation.
I steam my 1/19 scale TID (45" long) with a 1/2" bore x 5/8" stroke Borderer twin (.49 cu in) piston valve engine. Cheddar claimed that one of their Puffin plants was adequate for the Imara, a bit suprising perhaps.
Just suggesting that the D10 may not be the only option.
Regards
Keith
Keith,
You are quite correct, don't know where I was coming from but the Volume is 1.33 cub" for the D10.
I didn't mean that a D10 was the only engine but in my opinion it's the best.
I have made a Borderer piston valve engine but not using Reeves castings , I made it from stock material and made the cylinder head from a square cast iron window sash weight which was some load of rubbish.
The bore was 5/8" x 5/8" stroke and the beauty of the piston valve is the ability to reverse without all off the reverse linkage, I copied the reverse valve from the smaller Marcher engine and to prevent leakage on the piston valves I fitted Silicone "O" rings top and bottom.
I have made several D10's, with and without reversing gear and the present one in my tug is grossly over powered so 30PSI is enough.
I have seen an IMARA with the Cheddar engine and wasn't very impressed.
Keith, are you related to a Mrs M Goggins ( 93 years of age ) in Rochdale.
Ian ,
I don't like the Warrior engine as the Ali Standards more or less cover over the crank shaft and you can hardly see anything moving and it's a pig trying to get in to adjust the valve rod gland.
(http://s8.postimage.org/chpzwpoxd/P_VALVE_ENGINE_2.jpg) (http://postimage.org/image/chpzwpoxd/)
(http://s9.postimage.org/o0cm6lf97/P_VALVE_ENGINE_1.jpg) (http://postimage.org/image/o0cm6lf97/)
(http://s9.postimage.org/lx26yxfgb/P_VALVE_ENGINE_4.jpg) (http://postimage.org/image/lx26yxfgb/)
(http://s8.postimage.org/o0gahl6r5/D10_finished_3.jpg) (http://postimage.org/image/o0gahl6r5/)
(http://s9.postimage.org/3lyiehpq3/Double_Ten_5.jpg) (http://postimage.org/image/3lyiehpq3/)
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George......is the coil in the pump discharge line a form of snubber to to take out pulsations?..... :o .....I have not seen it used in model engineering.....Derek
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Hi OOYAH/2,
Thanks for the response. Nice pictures.
Out of interest, the TID was my first venture into steam and I went the route of making sure I had "adequate" power (plus a bit more) by making the full size Borderer and building a boiler to produce "adequate steam plus a bit more" (plus a bit more). I ended up with an expensive and heavy steam plant to big for my 1/20 TID. A rethink resulted in a scaled-up hull, a sleeved-down engine, a much smaller boiler and success, oh and some useful knowledge and a spare 5 1/2" return flue boiler which weighs 4kg.
My next model will still be fairly big (c.50") but I aim to keep the copper content (and cost) down starting with a relatively small engine.
I'm not surprised the Puffin/Imara did not impress you.
How did you guess, Mrs M Goggins (93) of Rochdale is my daughter.
Regards,
Keith
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Bertinats philosophy behind the "Borderer" was a request for something a bit smaller than the D10 and the bore and stroke sizes on the plans covered various options. Would have mentioned it, but the price of castings now means a second mortgage. Bought the casting set from Reeves when the series first apppeared in ME, for less than 50 pictures of HRH. Nearly fell orft me buffet when I saw last years price.
On the scaling point, I have photos of a "Galloper" made by a first timer using Alumininininum for the straight sided bits which looked ab - fab. Galloper?? that's what I christened it, a 2X Marcher and an absolute credit to its builder.
Only mentioned Warrior to fill the gaps George, strangely, Reeves quote both Borderer and Warrior as "Stationery" engines? Has the TID got a narrower waist than the other two?
Regards Ian.
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How did you guess, Mrs M Goggins (93) of Rochdale is my daughter.
Regards,
Keith
But your profile lists you as 67 years old.
Regards,
Gerald.
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Gerald,
B****r, guess my credibility rating has gone down.
Keith
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For info,
My 1/19 TID is 45" long x 11.5" beam, about the same as the Imara I think but probably a bit lighter at about 38lb.
Regards,
Keith
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George......is the coil in the pump discharge line a form of snubber to to take out pulsations?..... :o .....I have not seen it used in model engineering.....Derek
Derek
It is simply a long length of 5/32 " copper pipe rolled up to keep it tidy, at the time of building this engine I didn't have a test boiler so a feed had to be taken from my steam tug, hence the length.
Air vessels on toy steam engines are not required they may look the part but don't work.
I built a Single cylinder double acting engine using a Stuart 2.25" bore x 2" stroke cylinder casting and couldn't get an air vessel to work, the engine was powered by a Yarrow boiler that I made.
(http://s10.postimage.org/u914480md/Big_Engine_5.jpg) (http://postimage.org/image/u914480md/)
(http://s8.postimage.org/92kccyow1/Big_Engine_7.jpg) (http://postimage.org/image/92kccyow1/)
Keith,
I suspected that she might have been your Grand Daughter so maybe you should be called Methusela, any way I shall be in Rochdale over the Christmas holiday for 4 nights so I shall ask the dear old lady if she knows any Goggins in Oldham.
Ian,
Just had a look at Reeves Cat and the castings for the Borderer are quoted as £156 which is much cheaper than Stuarts D10 but Stuarts package includes all of the materials required to build the D10 so it may not be so attractive.
May I wish you all a happy and joyful Christmas.
George.
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Not sure if it still applies but the Borderer castings were all gunmetal.
And a happy Hogmanay to you George.
Regards Ian.
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It should not be too difficult to fabricate the main Borderer castings from bits of plate and bar, saving some weight as well as cost.
Interesting to compare the size of my 1/2" x 5/8" Borderer with the diminutive TRV1A of the same capacity - it offers some ideas on how an engine can be built without castings.
Keith
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Hullo & thanks George ....when you say......."Air vessels on toy steam engines are not required they may look the part but don't work" ....is it that we cannot accurately measure or monitor pulsation & any dampening effect at our low pressures of say......3.5 Bar with our model pressure gauge systems? >>:-( as in theory they [any fixed gas accumulator] must have a dampening effect............. <*<
Our member Bernhard........builder of open hull steam vessels has installed a form of accumulator in a number of his steam vessels.........possibly he may offer comment here :o
regards Derek
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Insert Quote
It should not be too difficult to fabricate the main Borderer castings from bits of plate and bar, saving some weight as well as cost
It's always difficult trying to advise the "What, How Why" questions as the modellers ability to "Build" is not usually given. An age thing usually predetermines that our generation threw Nowt away and passing a scrap heap (PRE Skip days) without winning a prize was unheard of.
The "Flexible friend" has changed the hobby entirely, as now, if you can't order one day and be on the pond the next, causes withdrawal symptoms in many and "Building" seems to be a dying art.
Regards Ian.
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Hullo & thanks George ....when you say......."Air vessels on toy steam engines are not required they may look the part but don't work" ....is it that we cannot accurately measure or monitor pulsation & any dampening effect at our low pressures of say......3.5 Bar with our model pressure gauge systems? >>:-( as in theory they [any fixed gas accumulator] must have a dampening effect............. <*<
Our member Bernhard........builder of open hull steam vessels has installed a form of accumulator in a number of his steam vessels.........possibly he may offer comment here :o
regards Derek
Hi Derek
If you can't accurately measure the dampening effect in such low pressures an air vessel it's not required.
Our friend Bernard as far as I can see builds superb model boats but I can't see any sign of engine and boiler builds.
One thing I am not and that is a model boat builder but have built many engines and boilers of all sizes including high pressure Flash steam plants and I assure you that air vessels on the delivery side of our small model pumps are not required and it didn't work on the larger engine that I posted a pic off.
Keith,
I must say that those little TVR engines are very well made and priced, being C.N.C. made , Graham can churn them out very quickly.
I had to do a repair on one once for a friend, the flanges on the manifold to the cylinder were leaking steam and he had messed about with the timing.
The timing was sorted quickly but my heart was in my mouth with the brass screws into the Ali cylinder block which by memory was 10 ba.
I was terrified that I would either drop the screw or strip the thread into the cylinder head, otherwise great little engines.
Ian,
One of the biggest problem in scratch building is buying small quantities of brass and steel, I have found that suppliers in Glasgow are not keen on cutting , say a 6" length of 1" round bright steel but quite willing to sell a 3 m length.
This is why I save up and put an order into Blackgates for stock material and collect when I visit Rochdale.
When I was in business and moving amongst engineering works I was able to pic up scrap lengths of materials , but alas no more,
George.
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Not sure if it is O K to put it on here or whether I should call myself a "trader" and put it in the Sales section but I did email Tugsmoke with some pictures of some New Zealand made engine kits so I guess it is relevant to this thread. As has been stated it is difficult to purchase small quantities of materials to build just one engine so these kits have been put together with all the neccessary materials including fasteners and a comprehensive set of drawings and instructions. I will add a couple of photos (I hope!) but if not have a look in the Traders section on Paddleducks http://www.paddleducks.co.uk/smf/index.php?topic=4885.0 The V Twin is 16mm by 16mm and the inline twin 20mm by 20mm. There are also single cylinder and Walking Beam kits available. The gentleman who makes them does not market them on the net but many have been built in this country, mostly through model engineers clubs. A lathe is essential and a mill or milling attachment a help to do all the maching but it is easy if the builder follows the instructions carefully. If anyone wants to know more send me an email or PM. Cheers, Ian.
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Hi,if you are looking to buy small lengths of material try m-machine they will sell by the inch but obviously the postage is a killer
Best wishes frazer
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Hi Frazer,
Thank's for the info, I use Blackgates as they will cut to my requirements and their postage will be the same .
I have used Blackgates for years and find them very helpful, I have the added advantage that I visit my family in Rochdale and if I make up an order I can collect when I visit, or my son when he comes up here can bring materials with him, saves postage. Happy Christmas.
George.
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Hi everyone
I have been on holiday which unfortunately included a unscheduled visit to a hospital in Tenerif so I have only just read all the posts on this thread I started. Thanks to everyone for their replies.
Ian (ciclip)
Thanks for the KNH references, I have obtained these but have not had time to read and digest them yet.
George (ooyah)
You say your your 32lb Cervia went OK on a Stuart V10 which is a 3/4 bore x 3/4 stroke single cylinder which is swept volume of 0.62 cubic ins. this suggests that the mentioned calculation of 0.7 to 0.8 cubic inches is about right for the Imara.
Keith (mrsgoggins)
Your 45 ins TID runs OK on a 1/2 ins bore x 5/8 ins stroke borderer. Thanks for that.
Well at the moment the bottom line from these comments seems to be that Borderer is about the right choice, with the decission about 1/2 inch or 5/8 inch bore to be deferred for the moment. I think the drawings are available from My Hobbystore. I understand that Model Engineer ran a series of articles on the construction of this engine I will have to check if these are still available - unless someone out there could help. I also would not pay £150 for a set of castings containing £5 worth of material. I will use stock bar etc. unless someone has some much cheaper castings.
Anyone like to comment on the Borderer option?
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George (ooyah)
You say your your 32lb Cervia went OK on a Stuart V10 which is a 3/4 bore x 3/4 stroke single cylinder which is swept volume of 0.62 cubic ins. this suggests that the mentioned calculation of 0.7 to 0.8 cubic inches is about right for the Imara.
Hi .
I have a copy of the article which was published in Model Engineer for the Borderer engine , article started on 1-12-89 to 7-12-90. ( 28 pages. )
These are photo copies taken from the Mag and are very readable,
If you wish P.M. your address I will post them to you if you will photo copy them and return my originals to me. ( don't put your address on the open Forum )
My Cervia with the 10V had ample power but being single cylinder it wasn't reliable in stopping and starting with the reverser that was made , hence it is now engined with a D10 complete with Stevenson link reverse. ( pics available on R&D S.T. Cervia an old lady )
The drawings for the Borderer are still available but from your statement that you don't wish to buy the castings this article has all the dimensions that you will need to scratch build from stock material.
In my opinion you should make the engine as per Bertinants drawings 5/8" x 5/8" as you will have the power on hand but don't have to use it all.
My preference of boats would be Cruiser as most of the rigging is fitted to the superstructure and gives quick and easy access to the steam plant.
Then I am biased as I used to see Cruiser on the Clyde when she was owned by Bennies.
Sorry to hear that your holiday was spoiled by a hospital visit, hope you are now well.
George
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Thanks to George and Ian I now have the build articles for Borderer and the drawings from My hobbies and have been trying to sort out some material.
I take George's point about cast iron being much cheaper than gunmetal however with corrosion in mind (and also I hate working cast iron - messy stuff) have been looking at gunmetal. Wow! I must retract my off hand remark on a previous post about the £150 casting set containing £5 worth of material :embarrassed:; the price of copper and it's alloys has gone completely crazy. I have been looking at some of the usual model engineers suppliers web sites and am amazed at the prices - gunmetal must be the new gold. In fact, if I cannot find cheaper suppliers, buying at least some of the casting set may not be such a bad option after all.
Keith (mrsgoggins)
I am interested to know more about your adventures with Border and a 5 1/2 inch boiler. After sleeving the engine to 1/2 inch bore x 5/8 stroke, what boiler did you use? what pressure did you run at? what prop did you use? any idea of the revs? and what was the performance like?
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The stroke remains the same for three suggested bores of Borderer, you don't sleeve it, just bore whatever diameter you choose. You can fabricate the block from lumps of bar and flat and Silver Solder together, ( too late to use decent Silver Solder now as it's past Jan. 1, THANKS BRUSSELS ) it's just a case of time/cost/value.
Regards Ian
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HI Did you notice one just went through on ebay in the not sold completed listings under the steam section it looks good it may be of interest ,regards Allan
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Thanks to George and Ian I now have the build articles for Borderer and the drawings from My hobbies and have been trying to sort out some material.
I take George's point about cast iron being much cheaper than gunmetal however with corrosion in mind (and also I hate working cast iron - messy stuff) have been looking at gunmetal. Wow! I must retract my off hand remark on a previous post about the £150 casting set containing £5 worth of material :embarrassed:; the price of copper and it's alloys has gone completely crazy. I have been looking at some of the usual model engineers suppliers web sites and am amazed at the prices - gunmetal must be the new gold. In fact, if I cannot find cheaper suppliers, buying at least some of the casting set may not be such a bad option after all.
Keith (mrsgoggins)
I am interested to know more about your adventures with Border and a 5 1/2 inch boiler. After sleeving the engine to 1/2 inch bore x 5/8 stroke, what boiler did you use? what pressure did you run at? what prop did you use? any idea of the revs? and what was the performance like?
Mike,
Have you considered just Cherry picking the castings that you will need, I am quite sure that Reeves will sell individual items, but then it may be just as well to buy the lot, depending in what comes with a set.
Another source of metal is a Scrap yard, where you can buy lumps of brass and other materials at scrap prices if you talk nicely to the man with the usual poor pensioner speel, and keep well away from the scrap yard dog.
I wouldn't worry about the rusting of cast iron as with the steam oil entering the cylinders they very rarely rust, only if left for a long period without using.
The 10V that was in my tug is about 12 year old and has never rusted, I use Silicone " O" rings in my engines and they hold a lot of oil, so you may reconsider Cast Iron.
George.
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Not the same engine but as an example :- http://www.homemodelenginemachinist.com/index.php?PHPSESSID=8e4f13b063c1e9817b9bc18d872661a6&topic=17218.msg176671;topicseen#new
Looks like he may be fitting Ball races for the main bearings, - not neccessary, it ain't an IC engine but Americans seem to delight in seeing the linkages as a blurr when running.
Regards Ian.
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Ian,
Had a look, not quite sure whether the brass cylinders are trunk guides or cylinders, think it could be guides as there are 4- columns to take an entabulator plate to carry the cylinders.
Must keep an eye on it to see where his design is going.
George.
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now the two cylinders i wanted to try an open type cylinder look with colums rather than a block type cylinder
Think they're the cylinders George, although on a second look, the main bearing blocks have an oiling point on top of both, so no races.
Regards Ian.
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Hi Pipercub1772
No I didn't see the Borderer engine on Ebay. I looked after I saw your post but could not find it. Thanks for the info anyway. Maybe he will re advertise it.
H George (ooyah)
I have been sorting out what material I need. I have cherry picked the castings as you suggested and will order these shortly. I have some rectangular brass bar which I think will be OK for the valve chests. I have an assortment of steel bar ends from which I have made a flywheel. The rest of the bar ends don't seem to machine very nicely so I am going to order some EN1A from College Metals for the steel bits. I intend to machine the crankshaft from solid and understand that the free cutting EN1A is best for this.
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Hi Mike,
As I have never machined a crank shaft from the solid I can only pass on comments that have been made before.
When doing so from the solid it's recommended that you anneal the bar before machining to stress relieve the bar.
If you are going to use free cutting EN1A I would be cautiuos as there is quite a quantity of lead in it and I don't know what effect annealing would do.
I always fabricate my shafts by glueing with Loctite 601 , leave over night and then taper pin all the joints before cutting out the piece of shaft not required, don't use roll pins as over time the joint comes apart.
Some people silver solder the shaft but I find it quite a hard cleen up job.
You should be able to fabricate most parts other than the cylinder casting, the trunk guides can be made from a piece of 3/4" round brass turned down to 11/16" dia with a flat piece of brass silver soldered to the end big enough to be machined to 1.125" dia as per the DRG.
It's then a simple turning job to machine the flanged end and bore thro' to size in the one setting and then cut the slots after machining.
Top and bottom covers from brass round.
Hope this helps and I look forward to your progress.
George.
As a base I use a piece of M/S flat but in hindsight should have used Aluminium to keep the o/all weight down.
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Hi George
Thats an interesting point about the crankshaft. As I said, I intend have go at machining the crankshaft from solid although I recognise that this may well be quite a tricky business. If in the end I cannot get a good result, your fabrication method using Loctite high strength adhesives sounds like a good alternative.
I have solved the cylinder block problem by not being such a skinflint and buying the Reeves casting along with some of the other castings like the eccentric straps etc. <:(
I have made a little more progress by making the eccentric sheaves from an old countershaft liberated when I refurbished My ML7. That was a nice piece of steel.
Another question that comes to mind is about the use of O rings rather than graphite yarn packing. The drawings show the piston and valve rod glands with conical finishes which is presumably intended, as the gland nut is tightened, to squeeze whatever is in the packing space onto the rod. Is this OK or should the finishes be flat so as to create a rectangular housing for the O ring, dimensioned to create an appropriate squeeze on the O ring as in normal engineering practice?
I am away all next week so will read you later.
Regards
Mike
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"O" rings are only specified on Piston, glands are for either graphited yarn or PTFE tape packing.
Regards Ian.
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Hi George
Thats an interesting point about the crankshaft. As I said, I intend have go at machining the crankshaft from solid although I recognise that this may well be quite a tricky business. If in the end I cannot get a good result, your fabrication method using Loctite high strength adhesives sounds like a good alternative.
I have solved the cylinder block problem by not being such a skinflint and buying the Reeves casting along with some of the other castings like the eccentric straps etc. <:(
I have made a little more progress by making the eccentric sheaves from an old countershaft liberated when I refurbished My ML7. That was a nice piece of steel.
Another question that comes to mind is about the use of O rings rather than graphite yarn packing. The drawings show the piston and valve rod glands with conical finishes which is presumably intended, as the gland nut is tightened, to squeeze whatever is in the packing space onto the rod. Is this OK or should the finishes be flat so as to create a rectangular housing for the O ring, dimensioned to create an appropriate squeeze on the O ring as in normal engineering practice?
I am away all next week so will read you later.
Regards
Mike
Mike,
The conical finish is created purely by the drill end but it does assist in crushing the packing yarn when the nut is screwed up.
When using yarn you should screw up the nut as tight as possible, which packs the yarn into the hole and then back off the nut, I always machine the nut face square to assist in the packing effect but if the nut has a c/sink it works as well..
"O" rings in a steam application should be Silicone and never crushed as they expand 100% under heat, so a groove must be made to suit the "O" ring and allow it to expand.
For instance , the valve rod on the Borderer is 5/32" dia , so an "O" ring with a 5/32 " bore and 9/32" Nom o/d and a cross section of .070, requires a groove machined to a depth of .057" min to .060" max depth and the width needs to be .094" min to .102" max width".
You will then have to form a tool cutter to get into the bottom cover to machine the groove to the tolerances quoted to allow the ring to expand under heat.
I use Silicone "O" rings exclusively on pistons but never on gland nuts, possibly because it's easier to use packing.
As Ian has said ,you can use ether Graphite packing or make your packing from Plumbers P.T.F.E white tape by rolling into a string and then packed into the gland.
I personally have never used P.T.F.E. tape but many have with good results.
Never crush Silicone 'O' rings and the black Viton rings are not recommended for packing glands or pistons, they melt and stick, trust me on that one !!
Hope that this helps
George.
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Hi George
Thanks for your last post. I guess I was thinking that the graphite packing was technology of yesteryear and that using O rings thoughout would be an improvement. However if a good seal is obtained on the piston and valve rods using graphite packing then good. As you point out it would be necessary to machine O ring grooves in the cylinder end cover and valve chest. In fact looking at the the valve chest drawings, it looks like it may be necessary to increase the gland nut thread size from that on the drawing, in order to get a .070 inch section O ring in. So I will go with silicon O rings on the pistons (thanks for the groove dimensions) and graphite string packing in the rod glands. I think both of these items are available from Blackgates.
Thanks again
Mike
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Hi Mike,
Don,t forget that the Silcone "O" rings are a different cross section for the piston rings than for piston rods.
I would suggest that you get a BLACKGATES Cat where there is a page with all off the tolerances required for fitting Silicone "O" rings, don't make the tolerances other than those that are listed.
Graphite packing on piston glands is O.K. and this is what has been used for years, some people still use graphite packing for pistons which again is O.K. but I prefer "O" rings.
George.
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Hi everyone and in particular Ian (circlip), George (ooyah) and Keith (mrsgoggins)
I have not made any posts for a while but I can report that work is progressing (if slowly) on my borderer engine. since last post I have made a crankshaft (from solid - phew) and main bearing assemblies and am currently working on the eccentric straps. I seems that the site has crashed in some fashion since my last visit so I have had to re-register using my original user name. I would like to re-establish contact with you guys but I do not know if you are still members and what your new user names might be. maybe you could post.
Mike
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Same as before, the Devil looks after his own.
Regards Ian.
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Hi Mike,
Still here same name just a bit older , not much wiser.
George,
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Hello Everyone
Well I suppose you all thought this chap has given up. Well I have not although I must admit that I has taken much longer than expected but I have at last got my Borderer engine to a stage which it has run OK on compressed air. There is still a boiler feed pump, regulator and lubricator to make not to mention the boiler, oil separator etc. So still a lot of work to do. I also harbour ideas of automatic boiler level and pressure control although I suppose providing the appropriate bosses are incorporated into the boiler, these things could be added as refinements later. I have tried to attach some pictures to this post but the program says my file is to large ie more than 300kbyte. I will try to sort that out.
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I have had great fun with this engine and I am now pleased with the performance. I needed to experiment a bit with packing including trying graphite packing and O rings. I have now settled for the O rings using the charts to ensure the correct depth and width.
The feed pump I found to be a little on the small size if you gear it down as shown, its fine if the bi pass valve is shut down perhaps something to consider.
Good luck with the rest of the build.
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Well at last I have got round to sorting out the pictures of my Borderer engine I think, so here goes at attaching them to this post.
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Lovely job. I have had great fun sailing my launch using this engine for the last two years.
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Beautiful work Mike :-)) ...are all of the bright steel components "inox" ....or stainless steel as we term it?...I cannot see evidence of surface grinding so if stainless were they from the 300 series & non magnetic? .....Derek
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Congratulations Mike,
Super piece of work, please don't put it in a glass case and sit it on a shelf, get it into a boat and make it work.
All the best
George.
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Looking good Mike, keep it up
Keith
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Do you have any plans for it?
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Hi chaps
Thanks for all the favourable comments. Well there is no stainless steel used on the engine. It's mainly just steel polished up a bit with emery tape here and there, brass, gunmetal and oh and the base is aluminium alloy. If you use steels with good machinability a good finish can be achieved straight off the tool. The pics are also brightly lit with a mix of daylight and flash which makes things look shiny. Full size drawings can be purchased from My Hobby Store (Plan No M65 for £12.00) and Reeves supply the castings (at a price). I have PDF files of the original construction articles which I will be happy to send if you email me at "XXXXXXXXXXX.com (michaelberry38@btinternet.com)"
It is not advisable use your email address on an open forum. To contact this member, please use the forum's mail system
ken
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Hi everyone
Well I have finished the boiler feed pump and on a simple bench test it appears to work OK ( see attached pic) I am now beginning to think about installation in the boat and all that may entail in the layout etc. So the first problem to encounter is the propeller. I understand that the thing to go for is the largest diameter which will fit together with a large pitch (1.5 times the diameter). I think an 80mm diameter will just about squeeze into the stern frame. The only prop I have found of this diameter is a Raboesch one which is square ie 80 mm pitch. On the other hand the only steam prop (pitch 1.5 times diameter) I have found is a Propshop one which is only 70mm diameter. Which would be the best bet or can anyone suggest something better. Oh I have also come across a Rivabo 80mm prop but Rivabo don't publish pitch information.
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;)....have mentioned before ........beautiful work Mike :-)) ...........I tried to count the pump reduction ratio but being in 3rd angle is only a guess.....16:56 teeth?......[14:1?]......
There is another UK prop manufacturer that I understood manufactured specials......George Streict?.........sorry :embarrassed: the spelling of the surname is incorrect, but I am sure another member will correct it..... Derek
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Possible competition here. %) :}
ken
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Hi everyone
Well Derek you did very well counting the gear teeth. I have the engine in my hand and gave up with the large gear and referred to the build information instead. Any how it is 15T and 55T so the ratio is approx. 3.7:1 reduction. The pump stroke is 1/4 inch and the bore should be 5/16 inch but wound up 8mm. You can guess how came about. :embarrassed:
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;)....have mentioned before ........beautiful work Mike :-)) ...........I tried to count the pump reduction ratio but being in 3rd angle is only a guess.....16:56 teeth?......[14:1?]......
There is another UK prop manufacturer that I understood manufactured specials......George Streict?.........sorry :embarrassed: the spelling of the surname is incorrect, but I am sure another member will correct it..... Derek
I think the name you are looking for is George Sitek http://www.gsitek-props.co.uk/
I have bought 'specials' from him in the past with good results and at a fair price. The only caveat I would mention is that he is a one-man band and you need to order early and allow a bit of extra time. Give him a ring and explain what you want.
Regards,
Barry M
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Your engine looks superb and love the finishing touches like the numbers on the connecting rods and all the studs same size also the solid crankshaft which I have not attempted to date ,great work
Cheers
John