I know this is a real long shot but I want to put a pneumatic drawbar on my Bridgeport, but i only have like 4.5 inches from the top of the drawbar to the ceiling so a butterfly impact just won't work so i was thinking of an air ratchet. but before i spend time trying to design a way to mount it I thought i would ask here if anyone has already done it and if they might have pics or plans.. thanks
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Air ratchet drawbar
- Thread starter sundown57
- Start date
- Joined
- Mar 26, 2018
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- 8,407
I have the same problem. I can't remove the draw bar without moving the head.
I stand on my tippy toes to tighten/loosen the draw bar.
- Joined
- Jan 7, 2016
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- 3,273
A couple of thoughts...
A 90-degree air ratchet, although changing direction, might be a challenge to figure out.
Or, what about a butterfly wrench with a cogged belt system? That might be a viable option, although a bit of a challenge to design and fabricate. Personally, I think that would be a neat challenge to undertake. Mount the butterfly wrench and the associated pulley to a plate whereas the entire assembly moves up and down. Utilizing a timing pulley on each end (air wrench and drawbar) with the associated timing belt.
https://www.mcmaster.com/pulleys/at-series-timing-belt-pulleys/
https://www.mcmaster.com/drive-belts/h-series-dust-free-timing-belts/
I realize that I may not have even matched up the pulley and timing belt series, but you get the idea. This was just a first-pass flyover of concepts.
A 90-degree air ratchet, although changing direction, might be a challenge to figure out.
Or, what about a butterfly wrench with a cogged belt system? That might be a viable option, although a bit of a challenge to design and fabricate. Personally, I think that would be a neat challenge to undertake. Mount the butterfly wrench and the associated pulley to a plate whereas the entire assembly moves up and down. Utilizing a timing pulley on each end (air wrench and drawbar) with the associated timing belt.
https://www.mcmaster.com/pulleys/at-series-timing-belt-pulleys/
https://www.mcmaster.com/drive-belts/h-series-dust-free-timing-belts/
I realize that I may not have even matched up the pulley and timing belt series, but you get the idea. This was just a first-pass flyover of concepts.
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I would be of the thought that the ratchet might be a bad idea. If you were to reverse the spindle the ratchet would not allow it to turn. The rotation of the spindle probably wear out the ratchet mechanism pretty quick also.
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It's not "automatic", but I've seen it done- What about just using the air ratchet instead of a wrench? From the outside looking in, it looks plenty more convenient than the "standard" box wrench. That fully eliminates the whole freewheeling issue right there. Easy access to the reversing mechanism, and I'm not recommending it.... But you can "swat" the drawbar respectfully with the neck, just below the ratchet head.
Again, just a thought. I don't even have a mill. I just know it works for somebody.
Again, just a thought. I don't even have a mill. I just know it works for somebody.
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- Jan 7, 2016
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- 3,273
Not really sure if I am following you on the description, but my power drawbar is not engaged when the mill is running. My power draw bar has a cam system that engages it when you select tighten or loosen
Yup you got me on that one. Thick head caused typing before thinking it through.