1/16 Bucyrus Erie 25B

[Jared]

Wrong thread, Jim, but that's ok. The tagline is led out through the front of the machine down near the boom pins and then up to a sheave so nothing really changes with the boom angle. I had to monkey with the spring geometry trying different tension and pivot points on the lever. I'm still not completely satisfied with it but it's good enough.

It's been long enough that I can't remember for sure, but I think the bucket required adding weight to it. I had to use thicker material for the bottoms and add weight to the center bar to get it to open reliably. That sand is pretty fine so pretty much anything works in it. It's volcanic ash from Mt St Helens when it erupted in 1980. The same stuff the gift shops sell a 1/2 oz vial for 10 bucks and the sand pits sell for 2 bucks a yard.

[Rvjimd]

Jared,

As a newbie machinist I have to ask. How or why did you decide to make the side frames from a single chunk of aluminum instead of starting with to pieces of bar stock and then bolting them together with spacers? It looks like a lot of milling to remove all that material in the middle? I have the same question about the center part? I was going to try an make the center from a 1/4" plate and then add "side skirts" to make the upside down box.

I made some of the sides using channel, but I think I'm going to redo them using two part of bar stock and spacers and then I can do rollers as you did.

Thanks again for the thread! I refer to it as I am working on mine.



Jim

[Jared]

Jim, the main reason I did it this way is because I have a mill and I wanted to play with it. Another reason is because it's easier to 3D model one part instead of having to draw and assemble multiple parts on the computer. With a built-up design, it could be a little harder to keep the inside and outside pieces aligned with each other if a bolt hole is just a little off. Although I suppose you could bolt the pieces together and then do all the machine work on them after. I would design a little fudge factor into the overall dimensions of the rough parts so they could be squared up with the mill after they were assembled if need be.

Actually, milling out the center was the easiest part. The outsides took the longest.

[Rvjimd]

Jared,

Thanks, that all makes sense to me now!

Jim