X2 mill power feed

[black85vette]

Just getting started on this project. Websterz was kind enough to send me a surplus drill motor that he got off eBay. I like these because of the clutch and gear reduction in them. I managed to get the chuck off after a short battle with it. Hard to remove something stuck when you can't get a good hold on the shaft it is threaded on to.

Did some exploring also. Took the trigger from a DeWalt screw driver apart to see what was in it. Very interesting. Looks like a small PWM circuit built into the trigger assembly. (see pic below) Makes sense. This indicates that the current required is pretty small because the heat sink is not very big. I put my bench supply on the motor and spun it up and confirmed that at full speed with 12 volts the current was well under 1 amp. That is the other nice thing about choosing this kind of motor. 12 volt power supplies are throw away items and I have 3 or 4 of them in a box.

Next thing I need is a Pulse Width Modulator for a speed control. I have started looking online and have some ideas but if anyone knows where to find one of these surplus or used please post. I could make my own and have done so with a 555 timer chip but just don't have the time right now.

I have a couple ideas on the coupler, mounting the motor and a cover for it. I will work on those while looking for the PWM.

 

[bentprop]

At least you got the chuck off without major drama,BV.
I had to hacksaw the shaft off a B&D one,only to find the thread was a left handed one .
I use a windscreen wiper motor myself on my slightly larger mill-drill,but the principle is the same.I used an old computer power supply,they're dirt cheap,and can supply a good 5 amps or more on the 12v rail.
For the PWM control,have a look at various electronic stores,they should have a fairly simple kit for such a beastie.However,if you use these,you WILL need to fit limit switches,cuz they don't like being stalled.It lets all the magic smoke out .
On the other hand,you simply replace the 2(or4)diodes,and you're good to go again.
Something like this:
http://www.electronickits.com/kit/complete/motor/ck1400.htm
I must get off my butt,and fit the Honda sliding roof motor I've got onto my Y axis.
Hans.

 

[websterz]

At least you got the chuck off without major drama,BV.
I had to hacksaw the shaft off a B&D one,only to find the thread was a left handed one .
I use a windscreen wiper motor myself on my slightly larger mill-drill,but the principle is the same.I used an old computer power supply,they're dirt cheap,and can supply a good 5 amps or more on the 12v rail.
For the PWM control,have a look at various electronic stores,they should have a fairly simple kit for such a beastie.However,if you use these,you WILL need to fit limit switches,cuz they don't like being stalled.It lets all the magic smoke out .
On the other hand,you simply replace the 2(or4)diodes,and you're good to go again.
Something like this:
http://www.electronickits.com/kit/complete/motor/ck1400.htm
I must get off my butt,and fit the Honda sliding roof motor I've got onto my Y axis.
Hans.

This is the one I use:

http://www.amazon.com/dp/B000WYAN92/?tag=skimlinks_replacement-20

Traces are already beefed up.

I'm looking forward to seeing how your build turns out Rick. based on your past posts I predict a winner! :bow:

 

[black85vette]

Got the next bit figured out. Went to the metal store and browsed the aluminum tubing. I wanted a thinner wall but settled for the closest fit. Plan is to house the motor inside the aluminum tube while leaving the clutch adjustment outside at the front next to the table. I cut away about .5" from the bezel that adjusts the clutch tension. This will make the mounting easier. I found some aluminum that is almost exactly the ID that the bezel will fit inside. Just some minor turning on the inside and it will be perfect. The motor will fit without a problem. Then I just need to fabricate some spacers that will go between the motor and the tubing. I am thinking Delrin since I have a bunch of it in odd end cuts that I got on eBay.

Next up is the mount to the mill and then the coupling. Still not finalized on the PWM controller

 

[black85vette]

Took a shot at mounting the motor. First pic shows the plate that holds everything together with 4 screws. The back side of this plate is also the surface that a bearing runs on allowing the clutch bezel to turn. Next pic shows the bezel cut back behind the round plate to give some clearance. Then finally I took some scrap .125" steel plate and cut it to fit the end of the mill table and low enough to mount the motor. Drilled some holes for the screws and the shaft of the motor.

 

[black85vette]

Motor mounted nicely and had plenty of clearance for the clutch bezel. Put it on the table and checked the fit. OK so far.

Still no decision on the PWM control.

 

[websterz]

Looking good!! I may have to rebuild mine. ;D

 

[black85vette]

Task for today was to make a coupling from the motor to the end of the lead screw. The lead screw has a slot cut in the end of it so I decided to put a roll pin through the coupling and have it ride in the slot. Because the slot is so long I was able to use that to have the coupling slide back away from the motor and disengage the power feed.

In the pics are the parts. I drilled and tapped a piece of aluminum to fit the threads on the motor where the chuck mounted. On the other end I counterbored space for the left handed screw and then cross drilled holes for another roll pin.

The coupling was drilled out to slide over the lead screw and the end of the motor shaft. I milled some slots to engage the pin on the motor shaft. Then I drilled and inserted a roll pin to ride in the slot of the lead screw.

 

[black85vette]

In these shots you can see how the coupling can be retracted for manual operation or slid over the pin in the motor shaft to engage the power feed. I tried it a couple of times and was able to just reach under and do it without having to bend down and see it to work the coupling.

Hooked up 12 volts and it operates both directions just fine at the lowest clutch setting. It is just too fast right now. Have some parts on order for the speed control and will work that part out next

 

[black85vette]

Have the power feed working now. Have tried a couple of home brew PWM solutions that were not what I wanted. I was getting pretty good results running off a DC supply so that is where I leave it for now. Plenty of torque at 5 volts from the supply. Made some test cuts in aluminum with a .5 inch end mill cutting 10 thou deep. Here is a video:

[ame]http://www.youtube.com/watch?v=evoQ9OAKbcU[/ame]

Also attached some pictures. Mounted the control switch on the front of the spindle assembly. Double pole, double throw with center off. Seemed to be a good place to mount because it is up and away from the moving parts plus the main reasons: 1. there were two existing holes and screws used to mount the shield (which I don't have) and I could make use of them without more drilling and tapping. 2. I had a small Radio Shack project box that was the perfect size for this location and the switch I bought.

I am using a variable power supply from my test bench because I can set the voltage anywhere I want and can also switch over and see how much current is being used. I will switch to something else later.

The best part is the cost. So far I am out $5 in postage, $5 for the aluminum pipe, $3 for the switch. So not counting bits that were surplus, already on hand, or donated the project total is a whopping $13. woohoo1

 

[Diy89]

Sweet. But whats the open end wrench for under the Z adj wheel?

 

[black85vette]

Sweet. But whats the open end wrench for under the Z adj wheel?

There is a round magnet there and I keep the wrench for the draw bar right where it is needed so I don't have to look for it! ;D

 

[Troutsqueezer]

Very nice. I think that's the cleanest version I've seen yet. How much current does it draw under load?

-T

 

[zeeprogrammer]

Nice. Only two problems with it....

1) Now I need one.
2) Remembering which way to throw the switch. Eh? Hm? Know what I mean?

Great job.

 

[oldguy]

Nice job, but I have a question.

What brand of drill is that motor assembly from? The few dead drills I've taken apart have used the case as the motor housing and weren't nearly as clean and neat as the one you've used.

I've played with using a windshield wiper motor or a window winder motor, but they must draw some big amps as they shut down an 8 amp rated power supply. You could probably even gear this one down a bit more and end up with more torque.

Glenn

 

[Artie]

I hear what you are saying Zee. It looks a great conversion, and its something I would never be without again, sort of like power steering, auto and airco in your car. Switch direction is never an issue, or at least never has been for me. Does it have limit switches Vette or are you relying on the drill clutch?

I rarely run onto mine but think they are a great safety item.

Well done mate.

 

[lathe nut]

black85vette ,that is very impressive, gosh the projects are piling up between you and Brian I would be able to get any rest for several hundred years, I have an older drill 110 Volt with the forward Reverse variable speed, might give that a try, thanks for the information that you have shared, great video, Lathe Nut

 

[zeeprogrammer]

Artie,

I was just having a friendly poke at B85V...I noticed the table start in one direction and then suddenly change direction. ;D Like someone toggled the switch the wrong way. ;D It would be something I would do but I wouldn't be so quick to correct...I'd still be saying 'what?'.

 

[black85vette]

How much current does it draw under load? -T

It draws about 2.1 amps at 5 volts

What brand of drill is that motor assembly from? The few dead drills I've taken apart have used the case as the motor housing and weren't nearly as clean and neat as the one you've used.

You could probably even gear this one down a bit more and end up with more torque. Glenn

Glenn, I am not 100% sure what brand it was. Websterz donated the motor and it was already out of the case. But based on how it compares to my 2 DeWalts it looks to be the same. Gearing down would be a lot more difficult than lowering the motor speed. You just don't want to go so low that it does not have enough torque.

What would be ideal is the motor in my larger cordless DeWalt drill. It has a high/low range and the low range would be absolutely perfect for this.

Yes, compared to a windshield wiper motor the drills use a lot less current because of battery life.

Does it have limit switches Vette or are you relying on the drill clutch?

No limit switches. In using my cordless drills I set the clutch and run the motor until the clutch releases all the time without an issue. Great way to not over tighten screws.

I have an older drill 110 Volt with the forward Reverse variable speed, might give that a try, Lathe Nut

Speed control on 110v is different and the motor may not be round. But that is the fun in projects like this. Use what you have, adapt and innovate. It is fun to me to take parts and think through a solution and sometimes take it the next step and make it simple and even another to make it clean.

I noticed the table start in one direction and then suddenly change direction. ;D Like someone toggled the switch the wrong way. ;D It would be something I would do but I wouldn't be so quick to correct

At least you didn't poke me about turning the Y axis wheel the wrong way. I did that too! Don't know how the math works out but when you have two options you have a 50% chance of getting it right, then why is it that 90% of the time I get it wrong????




Thanks for all the nice comments guys! Merry Christmas to all.

 

[websterz]

The motor is from a 14.4 volt Craftsman cordless drill.