Model Steam Donkey Engine

[dp]

Oh ye of little faith!!! I know that. I just haven't quite decided where/how to do that part yet.---But thanks for looking and commenting. I have to take everything apart for detailing and painting yet, and I will update the 3D model piping when I get to a point where I can decide how to do it.----Brian

"Braze" the last joint (with modeler's clay?)

[brian Rupnow]

Here we have a tale of bad luck, over confidence, or just plain old "dumb-assedness". First the good news----The boiler is painted with "Chassis Black" by VHT paints, which gives pretty well exactly the color and "hue" that I wanted. Not glaringly glossy, and yet not "flat black" either. The far side of the base is drilled and tapped for an air hose fitting in a very inconspicuous spot, and the air passage surfaces inside the boiler, where it connects via a flexible line to the "steam pipe" which exits thru the side of the stack and into my home made control valve. That part went very well. It was only while assembling all the piping to the cylinders that I discovered a mistake (can't call it anything else) that I had made. However I managed to do it, the cast 45 degree elbows are tapped in such a manner that they have a contained angle of 130 degrees, instead of the 135 degrees that they should have. This means that there is no way that I can assemble the piping as I had planned, as per the 3D model. I tried to heat one of the fittings, and "persuade" it to bend another 5 degrees, but the picture shows the result I had doing that. SO----I'm down four 45 x 1/4" cast elbows, and the minimum order from PM Research is $25. I toyed with the idea of machining 4 elbows from barstock, but I could never match the nicely cast 90 degree elbows that are okay. I'm kind of stuck for now, but I'll figure something out!!!----Brian

[sasquatch]

That IS a bummer, but you've come this far, i'm betting you'll have this solved soon!!

Good God!! Almost 20,000 views !!

[coalsmok]

Brian
Can you put the 45 the drill jig and bend the pipe? If you do it right at the joint I dont think it will be very noticable.

[Deja Vu]

A possible solution, since you are "gluing" the joints together, would be to redrill oversize the elbows at the correct angle and simply insert the tubing with "glue" leaving the threads on the "piping" exposed slightly for visual effects.
Or, split(with jewelers saw) the elbows on the inside of the corner and solder the gap...it too should be unnoticeable. But from your piicture of attempting to "bend" the elbow, this may not work.

By the way, Brian, I am thoroughly enjoying your construction projects...especially this one.

Thanks!

[JCHannum]

It is time to learn to bend pipe. Anneal the brass and make a shoe to fit the OD of the tube or purchase a tubing bender.

There is no shame in bending, and if done properly, it can look as classy as this model by Wilhelm Huxhold.

[brian Rupnow]

All is well! I called PM Research and explained my dilemma, and they are going to ship me out a "stick" of 45 degree cast elbows.

[brian Rupnow]

Nothing new build wise, as I have been seriously side-lined by some "real" work. However, I do have a question for those more knowledgeable than I am about these donkey steam winches. Obviously these winch drums had lots of cable on them, and it wouldn't always be in use. So---What did they do with the hook or whatever was on the end of the cable when it wasn't being used, but the engine was being run. They couldn't just let it flop and clatter around. Did they have a way to anchor the hook to the winch itself (which wants to turn even when the clutch is not engaged) or did they anchor the hook to something solid that wasn't part of the winch.---Which would seem pretty dangerous to me in case somebody engaged the clutch and pulled the machine apart. I'm curious, and since I don't plan on doing any real serious winching with my model, I may just lay up one complete wrap of rope and varnish it in place---but I'm not sure what to do with the hook at the end.----Brian

[sasquatch]

Interesting question which i have no clue to, but interested myself in the answer to this.

[Duffy]

I suppose that it depended very much on what the donkey was used for. If it was a pile driving rig, it was just left hooked up. The hammer would keep the lines tight at quitting time.
If it was a "high lead" logging show, then the donkey dragged itself to the foot of the main spar tree, (or nearby, usually close to a creek for water,) and the rigging crew set up the the two spars with guy cables and travelling block. The donkey drum lines would be led to the both the carriage and the actual hoisting pulley, as well as the haulback line. Everything would remain until the "side" was yarded out, which might take several days. A "side" for a high lead setup was an area of felled timber about 1000 feet square, with the two spars situated at the mid-point of each end. A single spar operation would be a semi-circle as much as 1200 feet in radius. The big rigs ran 1 1/2" main cable and the chokers were 3/4."
At quitting time, the rig was just left; there was nobody around to mess with it.