Tool changer option

[David]

Ran across this today. Looks quite interesting.
Looks like it's designed for ER11 - ER25 collets.

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[kstrauss]

I'm probably missing something. It appears that the magazine holds a bank of ER collets + nuts with the cutters inserted. How does that result in reproducible tool offsets? One video shows them measuring each tool after each change.

 

[David]

I'm probably missing something. It appears that the magazine holds a bank of ER collets + nuts with the cutters inserted. How does that result in reproducible tool offsets? One video shows them measuring each tool after each change.

I don't think the offsets are meant to be reproduced which is why each tool is measured.

Here's another video:

 

[slow-poke]

I wonder how much torque it applies to the nut when tightening?

 

[David]

I wonder how much torque it applies to the nut when tightening?

I think I read that it's in the 20Nm range but I need to verify that.

 

[slow-poke]

I think I read that it's in the 20Nm range but I need to verify that.

20Nm = 15ft-lbs
Might be okay for a router but seems entirely inadequate for a milling machine

 

[David]

Agreed. Torque spec on an ER25 is 77 ft/lbs. No way any spindle is going to generate that much torque.

 

[David]

Is collet wear a factor with high(er) tightening torques?

 

[Mike R]

watching the video, the tightening & loosening torque comes from the inertia in the spindle, so quite possible its hitting the required torque. Looks to me like wear on the collet nut will be a factor, already can see some marks showing on the nut where it engages the ball(s) in the tray. It is very innovative and accessible to hobbiest level and maybe the wear won't be a big factor for limited hobby use, or it at least isn't a bank account breaker to deal with it (new ER20 nut). I do wonder about the ER20 spindle and how it will wear with repeated tool changes, both on the thread and the collet seat. But even then, a replacement ER20 spindle is still a fraction of what a true tool change capable spindle and tool changer costs.

 

[David]

watching the video, the tightening & loosening torque comes from the inertia in the spindle, so quite possible its hitting the required torque. Looks to me like wear on the collet nut will be a factor, already can see some marks showing on the nut where it engages the ball(s) in the tray. It is very innovative and accessible to hobbiest level and maybe the wear won't be a big factor for limited hobby use, or it at least isn't a bank account breaker to deal with it (new ER20 nut). I do wonder about the ER20 spindle and how it will wear with repeated tool changes, both on the thread and the collet seat. But even then, a replacement ER20 spindle is still a fraction of what a true tool change capable spindle and tool changer costs.

Not even close to the torque levels I see online.
Here's a screen grab from the Mfg's Discord discussion about torque.
The mention of "taps" and "strikes" is how many times the spindle is ramped up to speed and stopped by the tool changer to tighten the collet nut.
So three taps = three runs to speed, say 1500 rpm and then hard stopped in the changer.
IMHO 17 ft/lbs is not going to prevent endmill pullout under any kind of serious tool load.

 

[drewnabobber]

They're using the spindle as an impact driver. The concept is fairly reasonable in that regard. Rego-fix does publish torque specs for ER collets with various tool sizes. If you dig into it, you will find that with 2 hits (the default) you are getting the torque spec for ~4mm tooling. Whether or not that is 'enough' torque and if the rest of the design compromises with the system are reasonable is an exercise for the reader.