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feed hold button
« on: September 25, 2010, 09:36:47 AM »
When you hit feedhold, the tool will generally keep moving a little further before it stop.  but  the cutter continue spinning
is there some way to have the tool lift out of the way when you hit feedhold.
thanks paul

Offline Hood

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Re: feed hold button
« Reply #1 on: September 25, 2010, 11:43:18 AM »
You can set up Stop to move to a safe Z height when pressed but not FeedHold as far as I know. You could however make a Brain that would raise the Z when it sees the FeedHold LED (OEM 805), maybe that would suit what you want?
Hood
Re: feed hold button
« Reply #2 on: September 25, 2010, 11:55:10 AM »
You can set up Stop to move to a safe Z height when pressed but not FeedHold as far as I know. You could however make a Brain that would raise the Z when it sees the FeedHold LED (OEM 805), maybe that would suit what you want?
Hood

But, then how would you un-do that so you could properly resume the cut??

Regards,
Ray L.
Regards,
Ray L.
Re: feed hold button
« Reply #3 on: September 25, 2010, 12:00:04 PM »
my next question was  exactly what ray ask 
paul

Offline Hood

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Re: feed hold button
« Reply #4 on: September 25, 2010, 04:45:36 PM »
I was meaning the brain would see the feedhold LED then do the Stop and if you had the option checked for Z to raise when Stop was seen then the only option would be to do a RFH or SNL.
Hood

Offline BR549

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Re: feed hold button
« Reply #5 on: September 25, 2010, 08:31:10 PM »
The only way I know to interupt the qued Z pulse stream is to use the THC UP function(;-). I worked on this problem for a long time and never found a good way to do it.

In a buffered system all the move data is already loaded into the buffer and no way to insert a Zup move. At least so far that I have found.(;-)

(;-) TP
« Last Edit: September 25, 2010, 08:43:04 PM by BR549 »

Offline Bjorn Toulouse

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Re: feed hold button
« Reply #6 on: September 25, 2010, 11:07:24 PM »
When you hit feedhold, the tool will generally keep moving a little further before it stop.  but  the cutter continue spinning



I noticed that as well while running a couple of the test programs.
Now, the spindle continuing to turn is normal (from my experience), but the having the axes feed continue after the button is activated, IMO, could lead to a dangerous situation.

Is this considered normal for Mach? I'm using a SmoothStepper, does the device contribute to the axes feed continuation after the button is activated?


Rex

Offline BR549

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Re: feed hold button
« Reply #7 on: September 26, 2010, 12:27:42 AM »
It is NORMAL for any buffered system. Mach has to plot a solution to create an end point then safely bring the system to a halt inside of the axis tuning parameters so you do not loose position, no lost steps.

So depending on your lookahead settings it may take mach a few moves to come to a safe stop.

It is NOT a safety concern. IF you need to STOP immediately then STOP or Estop  not feedhold (;-)

(;-) TP