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I bought a new one from H&W a while back. I don't know if it's a quality draw bar. I do think it threads in a bit too far.
I'm not having the problems I had that motivated me to replace it however.
Adding a washer is probably a prudent thing to do.
I like the confidence of the snug fit.
 
Janderso said:
I bought a new one from H&W a while back. I don't know if it's a quality draw bar. I do think it threads in a bit too far.
I'm not having the problems I had that motivated me to replace it however.
Adding a washer is probably a prudent thing to do.
I like the confidence of the snug fit.
Click to expand...
Generally, having the length of engaged threads at 1.5 times the thread diameter gets us about all the strength possible. With something that gets tightened and loosened often like a drawbar, I try to do better than that. With my drawbar, I am able to get almost two times the diameter of threads into the collets before they start binding up in the tapering threads of the collets. 1.75 times the 7/16" thread diameter of my drawbar to finger tight seemed to be the best compromise _for MY mill and MY collets_ and has been working quite well for me.
 
How would I determine how far the draw bar is going into the collett?
Revolutions?
Hold the collett up into the receiver and measure the free amount up top?
Not sure how to accomplish it.
 
Maybe set the draw bar in place and just start to thread the collet. Check the distance between the nose of the loose collet and the table. Then shove up on the collet and measure the difference. If you got 1" (for example), then remove the draw bar and thread it into the collet 1" if you can. If you can't and you've got 1 1/2 diameters of thread engagement, do like Bob suggested and add some spacer washers.

Bruce
 
Janderso said:
How would I determine how far the draw bar is going into the collett?
Revolutions?
Hold the collett up into the receiver and measure the free amount up top?
Not sure how to accomplish it.
Click to expand...
Count the turns it takes from first engagement, until it snugs up. Then measure the same number of threads on the drawbar (Or if you already know the TPI, divide the number of turns, by the TPI, and you have the distance the draw bar threads in the collet).
 
I bought three of these from All Electronics for a project and a spare. Very nice low RPM gear motor. Requires a 3 phase brushless driver. Huge torque, about 3 degrees of free rotation (backlash) in the output shaft. More details (drawings etc.) on their site. They sell just the motor too. Motor spec. is located in that listing.

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Welding turntable?
What you gonna do with it?
Cheap enough, that's for sure
 
Welding turntable is a great idea. Maybe I'll use the spare for that some day. Max speed is about 1 turn in 5 seconds. That's probably plenty fast.
The other two are to drive two large turn-tables for display purposes (customer project).
 
Brought my new toy home today. Went without a hitch. It was scary having the mill on the truck, just looked so top heavy. But I know most of the weight is down low, still took it very easy on the way home.

I'm going to try and sit the mill in place tomorrow. For now it's just inside the door. The forklift I rented actually clears my door. The only problem I see is I have a 2 post lift and I need to get over the cross member on the floor that has the hydraulics and cables in it. . I've put some wood down to try and stair step over the cross member. And with the heavy column in the back, not sure how lifting it from the front will go.

If I can do this is saves me from having to skate it into place.

After I get it in place I need to come up with a phase converter. Looking at a 25 hp one.


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