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[tugsmoke]

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 ; 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?

[Circlip]

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

[pipercub1772]

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

[ooyah/2]

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 ; 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.

[Circlip]

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.

[ooyah/2]

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.

[Circlip]

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.

[tugsmoke]

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.

[ooyah/2]

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.

[tugsmoke]

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

[Circlip]

"O" rings are only specified on Piston, glands are for either graphited yarn or PTFE tape packing.

  Regards  Ian.

[ooyah/2]

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.

[tugsmoke]

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

[ooyah/2]

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.

[tugsmoke]

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

[Circlip]

Same as before, the Devil looks after his own.

  Regards  Ian.

[ooyah/2]

Hi Mike,
Still here same name just a bit older , not much wiser.
George,

[tugsmoke]

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.

[steam up]

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.

[tugsmoke]

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.

[steam up]

Lovely job. I have had great fun sailing my launch using this engine for the last two years.

[derekwarner]

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

[ooyah/2]

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.

[mrsgoggins]

Looking good Mike, keep it up
Keith

[steam up]

Do you have any plans for it?