Ny-Lint Mobile Dragline Conversion

[Rvjimd]

I'll try that. I might try and put a slight cone shape on the face ends of the spacers so only the outer diameter touches the bar stock. I guess I could set the spacers on the surface plate and try to check if the ends are parallel?

[9W Monighan]

The spacers need to be faced square with each others end You probably chucked them and they were not running true. Then when you turned them around to do the other side it was running out again. Before you do that, try rotating them some so one will counter the other and maybe it will sit flat. Sometimes the flat bar stock will bow when you machine one side only due to surface tension.
All of the "I" beams I made for my dragline had a bow until I machined the other side.

[Rvjimd]

Steve,

Thanks for the tips! I was able to lightly clamp the assembly in the drill vise and then tighten the screws. This seems to allow it to stay flat enough to satisfy me for now.

Here is a video of the first test of the new drive tumbler. I have already started on the other side.

https://youtu.be/MTlgXVtkDjM

Jim

[modelman]

Jim-looks like you nailed it. The tracks are rotating smoothly with no jumping or jerking. Good job. If you still had the twisting problem I was going to suggest you bolt the-2-rails together tightly and see if they laid flat. Sometimes the holes can run-out enough to cause this. If the other side works this good you will be ready to go.

[Rvjimd]

Thanks Tom, can't wait to try it in some dirt! All we have here today is MUD, we got 3.5" of rain in about 4 hour today

Jim

[Rvjimd]

Second video of the crawler upgrade test. This is the same bit of video with some slow motion.

http://youtu.be/AYBJFvvS7wY

Jim

[modelman]

Jim-I can't see well enough to see the old tumbler but the new one seems to work perfectly. I like it!!

[Rvjimd]

I'm getting it! Got the upper and lower idlers made, just need to install them and put the track on and side two is complete!



Jim

[Rvjimd]

Well, that only took about a weeks worth of full time working in the shop! But, it is pretty much finished and I think it will perform much better now. Ball bearings on the new drive tumblers should really reduce the friction and stress on the chains and motors. The frame rails are now 1/4" wider than before and the tumblers and opposite end rollers, as well as the upper and lower rollers are wider to help keep the tracks flatter and support the machine. I changed the tension screws to an external location which is MUCH easier to adjust now.

I took it out in the back yard and tried it in the grass and a dirt pile by the pond. Seemed to work real good. I'm not getting any of the jerking like it did with the old drive tumblers. I think they were just to tight, but I really like the new style. Much easier to make than the old ones!

I want to make a dust cap for the bearing pockets but other than that, I like it! Brownsville will be a great field test for it, I hope we get some good weather, man was it soggy at the spring show!

Oh, and it anyone has a thought on it, I would like a better way to finish the tensioner. The way they are now, the brass rod rotates and the tension hold it against the tensioner bolt. Not ideal. I would like to put a collage around the end of the shaft but it can't be threaded, otherwise it would screw into the rod and seize it. I need to see this, guess I'll start searching the inter web...

[modelman]

Jim-sometimes these jobs take way more time than expected, but as long as the results are what you want is all that matters. I don't see a problem with the tensioners. Once you get them set, I doubt if you will need to adjust them unless you plan to crawl this model many many hours. The new track system looks and works great!!! You might consider putting a jam nut on the tensioner bolt in case it wants to move. Just a thought.

[frizzen]

That's looking really nice.

Why not shave the first couple threads off the drive tensioner, and make a saddle to support the axle so the tension screw won't be wearing on it. It already looks like you're wearing away at the brass.

[Rvjimd]

Friz,

Ya, you are right. I just haven't decided exactly how I want to do it yet. I'll probably let it wear fora few hours and see how it goes. The shaft will be easy to replace and I might also make them in steel. But I plan to eventually make some sort of saddle/collar on the shaft. Somehow then I should be able to let the delrin bushing run free on the shaft and hold the shaft fixed with the collars or something.

Jim

[Rvjimd]

Here is a little video making a five hole bolt circle in one of the boom pulleys on the crane.

http://youtu.be/pHBZeMw3kIU

Jim

[frizzen]

That's a really cool manual mill setup!

[doodlebug]

Originally Posted by Rvjimd

Here is a little video making a five hole bolt circle in one of the boom pulleys on the crane.

http://youtu.be/pHBZeMw3kIU

Jim

Thanks Jim, had no idea on what all a DRO will do!
Cheers, Neil.

[modelman]

Interesting video jim-I don't have the digital readouts but I can do the same thing with a rotary table. Your way looks more complicated to me. Do you think there is an advantage in using your method?

[Rvjimd]

Tom,

I have a 3 jaw mounted on my RT so the weight is at or above my ability to safely move it to and from the mill table and most of the time I have the vise mounted so that save me from the change out.

Here is something I learned from watching one of tom liptons videos of a similar topic-

For a bolt circle on a rotary table, the larger the diameter the more potential error introduced if the angle is not perfect. On the DRO, it wouldn't make any difference how large the circle was.

Another way to think about this comes from aircraft VOR navigation. At a radius of 60 miles from the transmitter station, a one degree deviation would put you off course by one mile. That would be a really large bolt circle, so probably not a concern.

Keep in mind that I only pretend to know much about this stuff!

Jim

[frizzen]

It's probably too late to help, but the unknown yellow machine pic you were modeling the new tracks on is a John Deere 690 / 690a

http://www.yesterdaystractors.com/cg...wlers&th=94405

[frizzen]

Sorry to keep cluttering your thread up, I couldn't tell from pics.. Did you put the swing servo at the back of the house below the drums, or where the operator would sit?

If it's operator seat, still have room for a figure? If it's under the drums, hom much worse is maintenance?

[Rvjimd]

No problem with clutter, you should see my shop right now!

My operator sits directly on the swing servo. The height worked out pretty good.

Jim