Nylint michigan crane conversion, hopefully

[frizzen]

next up, i took some 0.063" aluminum 2024 t3, and graph paper. I think this is a good start on side panels for a boom extension. That's the longest i could fit on 8.5x11 paper, i can post up template if anyone wants. Planning to make an even longer mid-boom just because i've got some longer aluminum. This one will put my boom reach at 32" once complete.



Then some brass stock turned into a windshield wiper and side mirror.

I really should try to get back to making drums soon so i can get back to servo mounts...

[frizzen]

I've been looking at servo accessories, trying to to come up with the easy way to do this instead of needing a lathe.

On servocity I've stumbled across 'servo shaft hubs' which are a splined 0.5" shaft and one end of the winch drum. Or they have 'servo shafts' that are just a shaft in 0.5 or 0.375 with the spline drive. I can probably fab up the other side plate, tap/die, and with a little locktite.

Hs645 uses their 'C1' 24t splines and i can find 32pitch and 48pitch gears to fit it made of Acetyl and brass. But i haven't figured out what the slew gear donor should be to make it all work.. i also learned the vex gears are 24 pitch.

[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

[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.