Nylint michigan crane conversion, hopefully

[SteinHDan]

What about a small gear motor with a drum on it, like this one?

- http://www.ebay.com/itm/262553977068


And control it with an ESC.


Best regards,
Stein :-)

[SteinHDan]

As an alternative, for the slew and pinon gears, maybe you could use something like this:
- Pinion: http://www.ebay.com/itm/151889646562
- Slew: http://www.ebay.com/itm/161891095040

You can see they have almost all types of bores, mods and number of teeth:
- http://www.ebay.com/sch/m.html?_odkw...+gear&_sacat=0

If you select a 4mm bore, then you can use a gear motor like this one:
- http://www.ebay.com/itm/381486411254

60 RPM / (66 teeth / 12 teeth) = 60rpm / 5.5 = 11 RPM

11 RPM for the swing would be quite ok, I think.


Best regards,
Stein :-)

[Rvjimd]

Frizz,

I'll turn the drums for you if you know what you want/need. Mine are pretty simple. You want them as large in diameter as you can fit nested next to each other. And for width I just wanted the drum to be centered in the "window".

Now, for the tricky part. I don't like the way I attached mine to the servo, but I have had no problems with them so far. I drilled and taped the servo spline screw hole to something larger, probably 2-56 or 4-40 I don't recall which. Then a matching stud installed in the drive end of each drum and a pin in the off end of the drum which is held by the support channel at the other end.

Ideally you would want the drive end to be a spline to match the servo but that is way past my machine skills and tooling.

Jim

[frizzen]

SteinHDan, that would work too. I was just planning on running the gearmotor/esc combo units like i'd seen on other cable machines like built by thestuff, smallhaul, rvjimd

Truckmaker, yeah you're right what can i say... i suck at building and having time/money.

I know the longer boom will impart a lot more moment on the machine, i just wanted to see how things change around, and more reach looks really cool. I'm also not above running lead ballast if it needs it.

jim, i greatly appriceate that.
I was thinking something maybe built off one of these:
https://www.servocity.com/standard-hub-horns
Thinking i can have a protrusion to index to the .500 hole and a flange to bolt on the near-side. i wasn't sure if it's worth it to have far-side support on the drums?

I need to break out calipers and think and mock up a bit before i'd be able to do a dimentional sketch for your consideration.

Or depending on the alloy you have, i might be able to just order a spare gearset and just broach the splines into a much simpler drum instead of getting that crazy.

[Rvjimd]

Frizz, do you have the servos already? If not, I highly recommend the hitec 645MG. Especially since I have some of them here already and I can use the round horn to make up a prototype drum.

I would do some off side support, it isn't too much more work and helps support and align the drums.

I'll do something on this today and see what I come up with. I am going to see if I can simply use one of the plastic horns that they come with. I don't think we need the metal spline version for strength. I'll post my progress here.

Jim

[Rvjimd]

How about like this? I'm about to drill the horn to the drum. Then it can be screwed to the servo through the center hole in the drum. The off side can then use a pin to support it.



Jim

[modelman]

Originally Posted by SteinHDan

If you select a 4mm bore, then you can use a gear motor like this one:
- http://www.ebay.com/itm/381486411254

60 RPM / (66 teeth / 12 teeth) = 60rpm / 5.5 = 11 RPM

11 RPM for the swing would be quite ok, I think.


Best regards,
Stein :-)

Nice to see old rigs like this converted. I think on a machine this size-3rpm would be the maximum you want for swing speed and maybe slower. On a dragline with hi-speed swing you will be slinging that bucket around uncontrollably. Also, the longer you make the boom the more boom tip speed you have. You also need a very smooth speed controller for the swing to keep the bucket from swinging wildly. Good luck and have fun.