Greetings all;

While adding a couple timedelays and a couple or2's to my hal file, 
basically to prove that I can pulse the spindle for the nominally 200 
msecs used to spin the nut on/off to release the collet and supposedly 
drop the tool, or just drop it all, I came up against a designed in 
problem.  This vfd has a pid in it that will no doubt wind up if the 
speed command is present for any great amount of time, so its possible I 
might have to cobble up a set of PID params to essentially disable that.  
Because I think I am going to need to have the speed present at the VI1 
input before I enable the fwd or reverse commands for the timed 200 
millisecs to drop or pick up the tool during the change. The wind up in 
that case might be advantageous in that it might jerk the nut loose, or 
tighten it tighter before the carousel puts the real tighten on it. But 
likely difficult to control too.

But I find its not possible to send this speed request before the run/dir 
signals. I can mux2 the spindle speed inputs to the 7i76, and have the 
as yet unwritten tool changer code issue the speed and timings.

Is that the choice?

A secondary problem if I do the 3d printed tool holders inside the collet 
sockets, like the orange pieces in one of the videos on hack-a-day, 
depending on the tool to drop free when the nut backs out the collet, is 
that the tool does not always come free, and this looks like a 
showstopper problem that puts me back to buying a handfull of nuts and 
collets so I can drop it all and then reposition the carousel to pick up 
the next tool/nut/collet as an assembly. Either way, it seems like I'll 
unavoidably need an automatic TLO setting to complete the change.

Thanks for any comments on my hair brained ideas. I figure on a bigger 
carousel than shown in the videos. That thought is driven by the 
difficulties I've had with the hand tightened (with a pair of 12 to 16" 
wrenches) on the ER32's on the G0704.

I've wrecked parts and broken tools because they'll walk out of the 
collet, dig too deep and finally break off.  That bit of history has 
cost me several hundred in tools so far. :(

Thanks for any wisdom shared.

Cheers, Gene Heskett
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <>

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