Yet Another Stuart Major Beam Engine

[simplyloco]

Not necessarily. The asbestos was quite often painted a dark colour, maybe because it was going to get dirty anyway, and also to stop it fraying.

Agreed. I made a test piece and it didn't look right: the paint accentuated the sharp edges of the cord.  The unpainted lacing cord fits well with the black/bright theme, so I'll leave things as they are.
Thanks for the inputs.
John

[simplyloco]

We have returned from our sojourn in Spain so watch this space!
John

[propforward]

 

[simplyloco]

Well, it's a start, innit?

[crueby]

Yup!   

[simplyloco]

Stuart Major Beam Radius Rods
Here's a few pics covering the first stage of their manufacture. The idea is to get the bearing housings exactly in line with each other and at the correct distance apart. I choose to fabricate bits like these rather than hack huge lumps of metal to shape! Today I've made the rings, faced off where the rod connects to provide a sound joint, and drilled a hole to take a joining pin. Tomorrow I'll make the rod bodies.

This is what is required. A precision job to ensure it all fits properly!



Free cutting stainless steel 0.625" diameter. A simple drill, ream and part off job.



Deburred to enable the bronze bearing to fit proper like!



This is the quick way to set up. The ring is 7/32" thick, so place a 7/32" rod in the chuck and use that to get the vice central. Replace with a small centre drill and using a feeler gauge, get the gauge level by eye. Drill 1.6mm and face off with a end mill. It is close enough!

[simplyloco]

More on Radius Rods

Turned and shaped a radius rod today, and silver soldered it to the bearing rings. The centre distance was near enough, and it was straight and correctly aligned. However, it turned out that the solder paste flux was not strong enough for the free cutting stainless I'm using, and the joints were very weak, and subsequently failed.
Anyway, here's the work sequence for your edification...


The bar is 7/32" diameter, and the length defined with a parting tool using the DRO to measure 2.894" from the end. I set the compound slide at 1.25 degrees and used a round nosed carbide profile tip. I parted it off, turned it round and did the other end. Finish with a smooth 6" file and varying emery cloth down to 400 grit.



It fits exactly!



Soldered up with dowel pins inserted and silver solder paste. I had to use a 20mm torch head to counteract the heat transfer!



t should have been 4.125", but so long as the other one is the same there shouldn't be a problem!



Cleaning up in the lathe. One end is pushed against the biggest collet I have, and the other is in the home made cup centre. It was perfectly safe!



Still the right size, and looking the part, but I'll have resolder using some stronger flux. Hey ho, thats model engineering for you!

[crueby]

Radius rods are looking good!  Do you have any silver solder wire so you could add a little extra solder for flowing through the joint, in addition to the paste stuff?

[simplyloco]

Radius rods are looking good!  Do you have any silver solder wire so you could add a little extra solder for flowing through the joint, in addition to the paste stuff?

Yes, it looks like I will go that way, or change the setup and introduce the solder from inside the ring.

[Jasonb]

You really need tenacity No 5 or CuP's HT5 as they contain something that removes the chromium oxide given off by heating the stainless steel that other fluxes don't. This will apply to whatever silver solder you are using.

Harris Black flux will do the same in the US

[crueby]

You really need tenacity No 5 or CuP's HT5 as they contain something that removes the chromium oxide given off by heating the stainless steel that other fluxes don't. This will apply to whatever silver solder you are using.

Harris Black flux will do the same in the US

I've used both the Tenacity 5 and the Harris Black, both work well, I like the Harris one better.

[simplyloco]

Piston Rod Crosshead

It's too cold to spend much time in the workshop, and the radius rods need time spent on them, but a quick clean job was this crosshead. Stainless steel, made from some 5/8" round bar, turned both ends and machined square in the mill. The end caps will be fitted later. There's a tapered hole in it to take the piston rod, which has a matching taper on its end. I didn't have a big enough taper pin reamer, but that's what friends are for...thanks Chris!
I have to make a fixing pin, but that can wait!

[crueby]

Looking terrific!
 

[simplyloco]

Those lucky souls who are building one of these may remember that I made a governor actuator, and promptly lost it, and had to make another. Well, it turned up today, having fallen into a little used drawer which must have been open at the time!
I'm open to offers, and I'm particularly fond of Tanqueray Gin...

[steam guy willy]

Hi, I have noticed on all the drawings the measurements are in fractional inches .... I do have this micrometer that has fractional as well as decimal and metric scales  ?!!! it is the only one I have seen though......also there are some measurements that are in metric  !!
Lovely build going on here...superb...

Willy