305 Koehring Build Start

[kerst]

Great!!!!!
Looking forward to following progress on this project!

Kerst

[9W Monighan]

Is that pipe thread? If so, you may want to try to remove the sharp "V" with a round file so the wire rope will not get frayed. Interesting idea using tapered pipe thread because on some of the 1:1 machines the hoist laggin is tapered so the ropes feet per minute increases as the hoist goes up .
Referring to my dragline; I have both LH and RH threads that I cut with a tool that I ground to a radius to conform to the wire rope. I figured out how many wraps ( threads per inch with room between) around the circumference I would need with a couple extra to have enough to hoist and drag in without any overlaps or running the hoist line off the drum. There actually wasn't too much figuring because I was building to the exact pitch diameters (in scale) as the 1:1 machine.

Hoist Laggin being cut on my lathe

[Trucker_Jo]

Looks good. Im building a yarder right now and plan to run 7 various drums and will have questions like yours as well.

[bartles]

I think the drum barrel area will either need less weld or I might bore out the flanges and well the barrel from the outside of the flange....definitely need less weld metal to machine lagging grooves in for sure. I need the thickness of the flanges in the barrel bore area to hold the ball bearings...I really don't want to machine bearing carriers. Like I said, my machining skills are rusty, and they weren't all that great to begin with!! This is going to be a fun project.

9W, no these are not pipe threads, just a poor job of spindle speed vs thread speed! Incidentally, nice job on your barrel machining....I think I'll copy your grooves with a more rounded lathe tool and increase the pitch to accommodate larger rope...and slow down my spindle speed for sure!! You will see smaller to larger diameter drum sizing in many shovel applications...the small diameter is utilized at the initial beginning of the dig cycle to help the machines break out force then increasing line speed to increase the machines cycle speed(according to a Koehring serviceman who helped us with a warranty repair/replacement service call)


Thanks

[Jared]

Yay! Another cable machine! How are you driving the drums?

[bartles]

My plans are to use two modified servos, via pinions and a bull gear arrangement from one of my helicopters, for each drum. I have a bunch of servo's, gears, pinions, bearings, shafts from my rc helicopters from which to choose. If my planning is correct I should be able to replicate the line speed and swing speed close to the real thing. One servo per drum would work but "when in doubt, go **** for stout".

[9W Monighan]

Originally Posted by bartles

9W, no these are not pipe threads, just a poor job of spindle speed vs thread speed! Incidentally, nice job on your barrel machining....I think I'll copy your grooves with a more rounded lathe tool and increase the pitch to accommodate larger rope...and slow down my spindle speed for sure!! You will see smaller to larger diameter drum sizing in many shovel applications...the small diameter is utilized at the initial beginning of the dig cycle to help the machines break out force then increasing line speed to increase the machines cycle speed(according to a Koehring serviceman who helped us with a warranty repair/replacement service call)
/

Thank you explaining the tapered drum better. I left that part out about smaller diameter giving more power for breakout force.
I can't remember what TPI I used to cut the laggins on my machine.
Do you have a prts book for your 305? I think I saw one on ebay yesterday

[bartles]

I probably bought the parts book you saw! It was pricy but really helps to scale components from for sure. I also bought a sales brochure from that era that has some great pictures to help me.

[9W Monighan]

Bartles, If you can't find the picture on my thread, Here is the one you wanted to see on how I attached the flanges to my hoist drum.