Author Topic: Help automating my bandmill sawhead (Read 5473 times)

Hbarker · « **on:** September 09, 2009, 07:25:02 pm »

Hello I have this bright idea of trying to automate my bandsaw mill , just the haed assembly.
With a gutted old electric wheelchair and a large satellite moving arm,
The wheel chair motors are 24v synced twin motors. we are mounting them on the outer rail to move the head forward and reverse,
And using the satellite arm to move the head up and down..
My question is have any of you guys tried this with those type motors and what suggestions you may have???
i have weather boxes for the batteries , and all will mount so that the head is still chargable and portable. and the bed is still just the bed..
any suggestions at this point are welcome..
will try and post pictures of the project.

pineywoods · « **Reply #1 on:** September 09, 2009, 08:42:53 pm »

Wheel chair motors are good. 24 volt dc but run fine on 12 volts. The wheel chair control box may or may not work on 12 volts. How do you propose to couple the motors to a drive mechanism? I doubt that powering the head support wheels would work. Chain drive like woodmizer would be easy and positive. The dish position box should work fine to raise and lower the head. It's just a big ole jackscrew with a gearbox and drive motor. Some were 24 volt dc, others were 110 volt ac, that would be a problem. Take pics, keep us updated, sounds like an interesting project...

Magicman · « **Reply #2 on:** September 09, 2009, 09:19:10 pm »

Horse power? Are you sure that you have enough to carry the load?

kelLOGg · « **Reply #3 on:** September 09, 2009, 09:21:59 pm »

Several people on the FF have done similar to what you describe. My photo gallery shows a 24vdc wheelchair motor that drives the head and a 12 vdc motor for the up/down. Others have probably done done it, too and probably better.
Bob

Hbarker · « **Reply #4 on:** September 09, 2009, 10:54:19 pm »

Quote from: Magicman on September 09, 2009, 09:19:10 pm

Horse power? Are you sure that you have enough to carry the load?

Not sure what HP ,, but they are designed to carry 300 lbs + the wheel chair ? 80lbs maybe.and I like that speed control most of all ,, should come in real handy.

Quote from: pineywoods on September 09, 2009, 08:42:53 pm

Wheel chair motors are good. 24 volt dc but run fine on 12 volts. The wheel chair control box may or may not work on 12 volts. How do you propose to couple the motors to a drive mechanism? I doubt that powering the head support wheels would work. Chain drive like woodmizer would be easy and positive. The dish position box should work fine to raise and lower the head. It's just a big ole jackscrew with a gearbox and drive motor. Some were 24 volt dc, others were 110 volt ac, that would be a problem. Take pics, keep us updated, sounds like an interesting project...

Now that one took some thought ,, then my buddy recomended using both motors since they are a pair.. and mount them to the sawcarraige legs on the outside of the sawmill. Leave the tires and they will press in and ride back and forth on the outside of the frame rail..
( least thats the plan ) also ,., those controls are made not to go very fast backing up.. so they will be mounted where reverse will actually be forward,, and forward ( a little faster in that same speed setting ) would be reverse ..

I like your rise and lower mechanism .. do you have any more pics from another angle? I can really see the screw jack part??

thanks for all the replies.. I will for sure take pics and post when I get to that point,,

I also plan on jacking the joystick control and wireing for foward, backward,
and left right be up and down,..
maybe a kill switch on the up/down while in forward motion..

I hope all was wrong with the chair was dead batteries......

Hbarker · « **Reply #5 on:** September 09, 2009, 11:07:53 pm »

one more question >>
After reaching the end of my cut i usually idle back down as I -for now manually- raise the head,, and return it to the and ,, to adjust for the next cut.. then rev up and make another slice,.
Seems this way I way only at full throttle while actually cutting..
Should I make a control for this ?? or leave it wide open and give it hell..

schmism · « **Reply #6 on:** September 10, 2009, 01:08:07 am »

throttle is a low force item and could be easly riged with an off the shelf RC servo. Local craigslist can hook you up with an older inexpensive RC car complete with servos, battery tx,rx

mburrow · « **Reply #7 on:** September 10, 2009, 09:42:52 am »

all the satellite dish motors I have seen are 36 volt dc,
I did try one with 12 volt it worked but was to slow for my needs on my mill

solidwoods · « **Reply #8 on:** September 10, 2009, 09:47:29 am »

I used a gearmotor from Grainger $125ish with a rehostadt.
jim

pineywoods · « **Reply #9 on:** September 10, 2009, 02:26:54 pm »

Hbarker, that wheel chair joystick probably don't work like you are thinking. Using left-right on joystick for up-down on head would be nice, but think about it. Left-right on the chair just makes one motor run backwards and the other forwards. The joystick is actually 2 controls in one package, so it could be done. Just use the drive for one motor to go forward-backwards and the other for up-down. I'm somewhat familiar with these gadgets, my wife is pretty much confined to one, plus I have built a couple. If the drive electronics are shot, I can point you to a place to get new(non wheelchair) controllers fairly cheap...

Hbarker · « **Reply #10 on:** September 10, 2009, 10:41:27 pm »

Quote from: pineywoods on September 10, 2009, 02:26:54 pm

Hbarker, that wheel chair joystick probably don't work like you are thinking. Using left-right on joystick for up-down on head would be nice, but think about it. Left-right on the chair just makes one motor run backwards and the other forwards. The joystick is actually 2 controls in one package, so it could be done. Just use the drive for one motor to go forward-backwards and the other for up-down. I'm somewhat familiar with these gadgets, my wife is pretty much confined to one, plus I have built a couple. If the drive electronics are shot, I can point you to a place to get new(non wheelchair) controllers fairly cheap...

Yeah I figured on rewire or hacking the control somehow,, I see what you mean as far as it right controls one motor and left controls the other ,, so may be a trick to that part, great on the pointing in right direction on controls,, got a link ? I may just use other controls if cheap enough..

Bruce_A · « **Reply #11 on:** September 11, 2009, 01:08:42 pm »

What happened to the forward and backward in a straight line control?

Hbarker · « **Reply #12 on:** September 11, 2009, 09:50:01 pm »

Quote from: Bruce_A on September 11, 2009, 01:08:42 pm

What happened to the forward and backward in a straight line control?

Strait line .... with both motors ,, one on right trac and one on left trac.they are syncronized motors no?

pineywoods · « **Reply #13 on:** September 12, 2009, 09:06:27 am »

Quote from: Hbarker on September 11, 2009, 09:50:01 pm

Quote from: Bruce_A on September 11, 2009, 01:08:42 pm
What happened to the forward and backward in a straight line control?

Strait line .... with both motors ,, one on right trac and one on left trac.they are syncronized motors no?

Nope, the 2 motors are not syncronized. They are just plain old 24 volt dc motors with a built in worm gear reduction box. Each motor has it's own independent speed controller, and the joystick is actually 2 separate potentiometers built in a common housing. Just mount the joystick flipped 180 degrees so what was forward is now reverse and reverse the 2 wires going into each motor. That will give you slow forward and fast reverse. Forget using left-right on the joystick for head up-down. The control box is probably all integrated circuits, would be a nightmare to hack. What does your mill use for a clutch ?

StorminN · « **Reply #14 on:** September 12, 2009, 01:01:37 pm »

Hbarker,

You've probably already figured this out, but most of those wheelchair motors have a (normally on) electrically-actuated brake... so if you end up using them without their normal controller, you've got to either power the brake to release it, or flip the mechanical lever on the side of the motor, which keeps the brake in "release" mode.

It seems like you could disconnect the side-to-side potentiometer in the joystick, so that would leave you with just straight-ahead and straight-back movements, and no reversing of one motor in relation to the other (both would always spin the same direction).

I'll second mburrow's comment... all the satellite motors I've messed with are 36VDC, but I've run them on 12VDC... much slower, but they work. I imagine amp draw at 12V could be an issue if they were under a heavy load...

I vote for a control on the throttle, saving on fuel is always a good thing...

-Norm.

Hbarker · « **Reply #15 on:** September 12, 2009, 09:48:32 pm »

Thanks for the replies fellas, I got one motor mounted today and the other one ready to put on ,, I will get a picture tomorrow when its light out so you can see how I have mounted it,..
Seems like one motor on the one side may be enough to carry the lad, I have not powered it up yet, But I supose one on each side would give it a even push...

Hmmmm ,, yeah that *DanG break,,
I am trying to use just the stay arm itself and not take the gear motor off of it because of its stout "stay in position" ability for up and down control in hopes of not needing a break, yeah its a little slow and Ive yet to locate a perfect lift point on my mill head,..
Worm drive , a break , and a couple spockets may be an easier alternative.. $:-\$

Hbarker · « **Reply #16 on:** September 12, 2009, 10:23:48 pm »

Tom

well couldnt figure how to make it show in post,, but there is a pic of the right side motor..

I am looking at that picture and almost have in my mind to take the tire off,, and run a steal cable from one end of the mill to the other ,, just wrap it around that wheel hub.. and see id that works.. but the other way my saw head can be lifted off with the tractor and stored without removing anything.. Hmmmmm $:-\$

fishpharmer · « **Reply #17 on:** September 12, 2009, 10:58:32 pm »

Quote from: Hbarker on September 12, 2009, 10:23:48 pm

(Image hidden from quote, click to view.)

I am looking at that picture and almost have in my mind to take the tire off,, and run a steal cable from one end of the mill to the other ,, just wrap it around that wheel hub.. and see id that works.. but the other way my saw head can be lifted off with the tractor and stored without removing anything.. Hmmmmm $:-\$

Hbarker, I have a similar idea using a 12 V atv winch. I am close to having it completed. I am gonna wrap the cable around the drum and secure it on each end with turnbuckles to adjust for any stretch. I am concerned the winch (Harbor Freight) won't hold up.

You need to post up some pics of your mill. FF members have an endless amount of knowledge (except me)

Hbarker · « **Reply #18 on:** September 12, 2009, 11:05:30 pm »

wench would be slow for return to cutting position ,, but great I would think for forwward motion ,, I woul dlike to return to cutting position as fast as safely possible,.

I can almost see y mill taking off across the yard and slicing down a bunch of trees, or god forbid hitting some thing or someone..

fishpharmer · « **Reply #19 on:** September 12, 2009, 11:09:10 pm »

agreed, it will be slow. But since its manual and the sawhead is huge. 48 inches between the rails on the log bunks approximately 1000 pounds. I figured a slow return would be an improvement for my back

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Author Topic: Help automating my bandmill sawhead (Read 5473 times)