Building a shay locomotive

[Martin Shaw]

APT are about 5 miles from me in a non descript warehouse on Hillington industrial estate, originally set up during the war to provide an alternative location for Rolls-Royce to make Merlin engines for Spitfires and Lancasters. I can thoroughly recommend them for economic pricing and quick service, most of my insert tooling has come from them recently at prices that are on a par or better than the hobby suppliers, especially if your prepared to purchase quantities rather than one offs. Drill Service Horley are another very good supplier with keen prices, use them a bit as well.
Regards
Martin

 

[mike evans]

APT are about 5 miles from me in a non descript warehouse on Hillington industrial estate, originally set up during the war to provide an alternative location for Rolls-Royce to make Merlin engines for Spitfires and Lancasters. I can thoroughly recommend them for economic pricing and quick service, most of my insert tooling has come from them recently at prices that are on a par or better than the hobby suppliers, especially if your prepared to purchase quantities rather than one offs. Drill Service Horley are another very good supplier with keen prices, use them a bit as well.
Regards
Martin

Hello Martin
Many thanks for the info.
I have been using Drill Service at Horley for several years for drill bits, reamers and milling cutters.
The APT mini boring bars and internal grooving bars are certainly of great interest to me and the prices seem very reasonable.

ATB

Mike

 

[Martin Shaw]

Mike
Just for info, shown is my smallest boring bar from APT, 8mm in dia with a CCGT insert fits into a 10mm. Cost currently £13 sans VAT which doesn't strike me as expensive. The spectacles bored using the bar were the first attempt for one of my 16mm diesels, I need 4 and didn't have enough sticking out of the chuck, oh dear silly me never mind.
Martin

 

[adrian]

I have to locate some stainless spring wire to make the springs that hold the stainless ball in place.
Has anyone any ideas where I might buy this, please ?

Just seen a link to Just the ticket Supplies - they have a good range of materials, obviously gauge 1 live steam orientated but his catalogue does list a couple of stainless steel springs which may be suitable.

https://www.justtheticketsupplies.co.uk/wp-content/uploads/2022/07/JTT-Cat-June-22.pdf

Also a good price and range of BA nuts & bolts and other material stock.

 

[mike evans]

I thought this might be of interest so some.
The boiler is supported to the front on a bracket at each side of the smoke box.
The positioning of these brackets is crucial for the correct alignment of the boiler.
This is achieved by making up a jig, well explained in the book by Kozo.
A 2mm thick brass disc is turned on the lathe to 80mm diameter and two half moon shapes are cut from it.
A piece of 1.5mm brass is cut and rolled to fit.








The two segments are to be drilled and tapped on the edge of the brass.
First I marked and made a small dot punch mark in the centre of the 2mm, then checked and adjusted as required.
Now drill a 1.3 hole and tap 1.6mm using a spiral flute tap with a dab of grease.
I found it important for the drilling and tapping to have the brass level with the top of the vice jaws. This prevents any material ‘bulging’ out.





The rolled brass strip is marked and drilled 1.7mm.
Using 1.6mm socket head screws the assembly of the main part of the jig is put together.
When happy with the fit the screws will be removed, flux applied, screwed back together and the assembly silver soldered.
I will post more photos as the jig progresses

 

[mike evans]

Further work on the smoke box supports.

The structure has been silver soldered and milled to dimension.
Using the height gauge the horizontal centre line is marked and hole positions to both ends. The vertical centre line is marked from the edges and the hole positions.


The structure is now set up in the Mill, and using an 8mm cutter an 8mm hole is made in both ends working off the centre lines
Using 8mm brass bar machined to 80mm length a 3mm hole is tapped 10mm deep in both ends.

This bar is now silver soldered into the two holes making sure it protrudes equally at both ends

Having spent several hours making this it is now time to cut away all the 2mm side segments.
Reduce the width of the rolled brass to 16mm central about the 8mm brass bar.

Using the height gauge each end is marked where a cut will be made
First cut away the 8mm brass bar then cut along the marked ends




After cleaning up, drilling and tapping 2mm holes I finally have two supports which are fixed to the smoke box with 2mm socket head screws.



Looking at the photos I am not happy with shape of the plate with the holes so I will revisit these. Looking at the end of the 8mm brass bar the plate should look circular.
This has been quite a marathon , get the shape right, and all the dimensions check out Ok so hopefully all should be fine.

Mike

 

[simond]

Mike,

an impressive bit of work! If you are really going to remake them, could you cut the assembly in half after soldering, remove some of the waste from the sheet materials, and then chuck the nascent parts by the bit of tube on the inside, and turn the flanges?

If so, you could also spot the screw/rivet holes with a tool-post-mounted drill, although I suspect these should be radial to the smokebox, rather than parallel to the tube axis. You can then cut the tube off flush and finish the inside surface.

 

[mike evans]

Mike,

an impressive bit of work! If you are really going to remake them, could you cut the assembly in half after soldering, remove some of the waste from the sheet materials, and then chuck the nascent parts by the bit of tube on the inside, and turn the flanges?

If so, you could also spot the screw/rivet holes with a tool-post-mounted drill, although I suspect these should be radial to the smokebox, rather than parallel to the tube axis. You can then cut the tube off flush and finish the inside surface.

Hi Simon
Thanks for your kind comment.
No, I am not going to remake them, I can’t go through all that again!
Just a tweek here and there on the overall shape of the brass plate.
I wish I had thought of your idea of turning the flanges- much easier. Hind site heh!

Mike

 

[simond]

Well, can you fit them on a mandrel to turn them? (I quite agree, I wouldn’t make them again either!)

You’d need to be creative with the clamping arrangement, but having got this far, I’m sure you can support them somehow!

 

[OzzyO]

Bit of bar in the chuck drill and tap the appropriate size for the 8mm bar to screw on to a length of studding that's thread locked into the bar and turn to size.
Getting it off maybe a bit of a challenge.

OzzyO.

 

[mike evans]

Bit of bar in the chuck drill and tap the appropriate size for the 8mm bar to screw on to a length of studding that's thread locked into the bar and turn to size.
Getting it off maybe a bit of a challenge.

OzzyO.

Hello Ozzyo
I was thinking along those lines in as much that the 8mm brass bar is tapped M3.
So, a length of, say 8mm steel bar turned down and threaded M3 leaving a square shoulder for the 8mm brass bar fitting to screw onto.

I need to be very careful turning the flange as the last thing I want is to make the fitting again.
I’ll post how it all works out.

Mike

 

[mike evans]

Thanks Simon and OzzyO for your suggestions on achieving the shape that I wanted.
Here is a photo of the part on the lathe having been machined to the correct profile.

Mike

 

[michael mott]

So Often the set up to make a small part requires ten times more work that the actual part itself appears to have cost. The outcome of your effort look great though.

Michael

 

[mike evans]

Unable to source the M2 hex bolts that I require for the Shay smoke box I decided to have a go at making them on the lathe.
I need M2 x 3.5 long and M2 x 7mm long

The dimension across the flat on 2mm bolt is 4mm so I used 4mm brass hex bar.
I checked the position of the tool on the horizontal centre line of the work and made a small adjustment. Before I did this I honed the cutting edges to be sharp.
Because of this the hex bar could be reduced to 2mm dia. In one pass.
Using A file with slow speed I created a leading edge for the die and threaded the bar.
By using a 0.5mm wide mini thin to part off the bolt less material was wasted.

Once the bolt passed muster the remaining bolts did not take too long to make with the time passing by quite quickly.

Here are some photos showing the lathe operations and a photo of the finished bolts

I hope you find this interesting
Mike

 

[mike evans]

I have had a problem bending 5mm od x .06 wall thickness copper pipe for the Shay blower.
My solution, after failed attempts, was to fill the pipe with soft solder then use the bender to produce a perfect bend in the pipe. Re heat the pipe and the solder flows out.
Are bending springs available for small bore copper pipe or any other suggestions without using the solder?



Mike

 

[J_F_S]

Silver sand is a cheaper method - just fill the tube then crimp or solder the ends. Bit fiddly when the tube is so small!

Cheers,
Howard

 

[Dave Holt]

It might be a good idea to anneal the tube before bending, if you haven't already. That's normal full sized practice.
Dave.

 

[mike evans]

More progress with the Shay having made the manifold and fittings.
Milled the brass to size, set up the four jaw Chuck and drilled and reamed the holes and faced one hole.
The 10mm reamed hole has an inside groove 12mm diam. X 5mm long.
I used a mini internal grooving tool for the job. Worked out well.


Now to make two threaded inserts.
I turned down a brass bar to the required diameter for 3/16 x 40 thread and the end I turned to 3mm x 2mm deep.
After threading I parted off the part to dimension

The parted end has a 3mm hole x 2mm deep bored into it. I don’t think holding this in the Chuck would work so my solution is to drill and tap a round brass bar to 3/16 x 40 thread and use this as a fixture.

Now I have all the parts for the manifold the two threaded parts are silver soldered to the brass block.
I was mindful that silver solder on the thread and in the hole was a bad idea.
So, I put minimal flux on the face of the block and tapped the parts into the holes which were made as a snug fit.
I cut off two pieces of 0.7 dia. Silver solder rod about 5mm long and curved them to suit. One piece of solder was placed on each part.
I then heated the block with the heat furthest from the joints. When all reached the correct temperature the solder made the joint.


I hope you find this interesting

Mike

 

[mike evans]

The fire box grate for the Shay is made from 304 stainless flat strip which I have bought.
There are 2NO. 3mm holes drilled in each piece which went OK.
However, each end of the bar has two milled notches 3.5mm x 3.5mm and the bar is 3mm thick.
I have tried an indexable cutter with three inserts but after two passes the inserts have had it.
It has been suggested that I should use a carbide end Mill TiN coated using plenty of coolant.

Has anyone experience of this or any other ideas that would work please ?

Many thanks

Mike

 

[simond]

Hi Mike

We do quite a bit of 303/4 at work, much easier than 316 which is horrid stuff. I’ll ask the machinist and let you know