Hi All,

After reading as much as I can, and reading through all of the thread
What The World's Been Waiting For - Yet Another Power Drawbar Design
http://www.machsupport.com/forum/index.php/topic,11826.0.html

An interesting discussion on how much tension force is needed.

But my big question is how much total deflection is needed?

If anyone is using a TTS ATC System, how much travel in the spring washers is needed to ensure a good tool release?

Thank you for your time,

TJ

0.100" is plenty.  0.050" will do it in most cases.

Regards,
Ray L.

I guessed correct. Now that's just odd.

Thank you for your time.
TJ

Ray, did you ever post pictures of your final configuration?

Randy

Ray, did you ever post pictures of your final configuration?

Randy

Randy,

Not really.  I abandoned the Belleville drawbar, because it just wasn't practical to get enough tension to properly hold a tool in a collet.  For a while, I used an impact wrench drawbar, but HATED the racket, and the wear on the drawbar and socket, so I removed it after a few months.  My "final" approach is a stepper motor with planetary gear reducer.  This will provide MORE than enough torque (up to 75 ft-lbs!), and allow the drawbar to be loosened just a few turns (for Tormach-style holders), or unscrewed completely, under software control.  But, as I've just returned to work, following 19 months of unemployment, I have very little time to get out to the shop.....

Regards,
Ray L.

But, as I've just returned to work, following 19 months of unemployment, I have very little time to get out to the shop....

Good on ya, Ray!  I hope to be in that position myself really soon now (17 months and counting of unemployment for me...)

I think yours is the first motor-driven drawbar that I've heard of.  Scott_M over on CNCZone has a new handlever-operated hydraulic-force-multiplier TTS drawbar, but of course the Tormach doesn't have a quill...

Randy

Very interesting.....
http://cnczone.com/forums/showthread.php?t=100231
Thanks Randy

Quote from: HimyKabibble on March 15, 2010, 09:38:15 PM

But, as I've just returned to work, following 19 months of unemployment, I have very little time to get out to the shop....

Good on ya, Ray!  I hope to be in that position myself really soon now (17 months and counting of unemployment for me...)

I think yours is the first motor-driven drawbar that I've heard of.  Scott_M over on CNCZone has a new handlever-operated hydraulic-force-multiplier TTS drawbar, but of course the Tormach doesn't have a quill...

Randy

Randy,

Yes, no quill makes it a LOT easier.  I wonder how that lever-operated one will wear with use.  There's a LOT of pressure on those little cams and levers.  It wouldn't surprise me if they wore and loosened up over time.  Very nice execution though!

Regards,
Ray L.