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Author Topic: Drives falut out  (Read 8332 times)

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Re: Drives falut out
« Reply #10 on: September 12, 2011, 07:07:33 PM »
Hood
what you mentioned above is what's happening, but with a twist my drives fault and mach keeps feeding the g-code i see it and stop mach then i have reset the drives and rewind the code then try and find my exact home position which is not all way's exact. What i do is run the machine until it gets to a point where i can gauge how far it's off and then home it back to zero and jog the machine i do this on both the X and Y axis this is what i am trying to get away from.

Dennis   

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Re: Drives falut out
« Reply #11 on: September 12, 2011, 08:01:42 PM »
If you have accurate home switches then you would  not have these problems. Home the machine on start up jog to where you want the offset zero to be then if for any reason you get out of position and need to restart at any point in the code its just a case of re-homing and doing a Run From Here.
This also brings up a question, it sounds like your drives are constantly faulting, why is that? there must be something wrong somewhere.
Hood

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Re: Drives falut out
« Reply #12 on: September 12, 2011, 10:47:32 PM »
You would still have to "accurately" reset the point of origin X0Y0(workhome) to be able to restart. Unless you programmed everthing based off of Machine Zero(refHome) OR have Fixture offsets preset to the part. SO really Refhome does not gain you much.

Irregardless IF you loose a drive(fault) you have to reset everything anyway, there is NO going back from that point.

Just a thought(;-) TP

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Re: Drives falut out
« Reply #13 on: September 13, 2011, 04:42:44 AM »
SO really Refhome does not gain you much.
Just a thought(;-) TP

Terry please explain why you are saying that?

Hood

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Re: Drives falut out
« Reply #14 on: September 13, 2011, 10:25:07 AM »
With Mach3 it sets itself up in machine coord everytime you startup. It is not required that you refhome to do work.  Just clamp a pierce of material to the table. BUT then you must set the point of origin for the part to be machined. So you touch off the material and zero the table X0 Y0. You have just set G54 as your fixture offset.

You never machine in machine coords so really it does not matter where they are to mach it is just a reference base.

So lets say you crash mach and need to resetup to begin again.Simple just go back and touchoff on the material set XY to zero and off you go again.

SO unless you program your part origin based on the machine zero you still have to set the work offset to verify it is correct so WHY double your work.

Many Low End machines today do not even HAVE a homing system they run in User co0rds(work offsets) just like in Mach's case.

I have USED both types of systems and I do not see any difference in crash recovery except the Refhome method takes longer on startup and crash recovery.  The machine accuracy level is exactly the same.

NOW IF you have a dedicated table full of fixturing and have setup Fixture offsets for all the fixtures THEN refhome makes sense as then you only have to set the MachineZero to establish the POO for ALL the fixtures at once. BUT you can still do that manually in mach you do NOT have to have switches  or wiring to do so.

Just a thought, (;-)TP

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Re: Drives falut out
« Reply #15 on: September 13, 2011, 02:23:04 PM »
Terry to me there is nothing simpler than pressing RefAll to home to switches when  you first start the machine, jog to where you want the X Y zero position to be and zero the DROs then off you go. Anything goes wrong and you need to restart or pick up at a point in code its just a case of RefAll again then you are all set.
Even stopping the machine half way through a large job, shutting down overnight and restarting the next day only requires a RefAll and you are all set, no pissing about with having to touch off which in itself may be a time consuming process, especially if accuracy is needed.

Just my  thoughts ;)

Hood

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Re: Drives falut out
« Reply #16 on: September 13, 2011, 02:35:12 PM »
Hood You still have to TOUCHOFF to accurately set the X0Y0Z0 to the material or fixture or vise,etc

(;-)TP

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Re: Drives falut out
« Reply #17 on: September 13, 2011, 02:43:26 PM »
Only the first time Terry ;)  The difference between the way I work and the way you work is the Referencing at the beginning, if nothing goes wrong or you do not have to shut down and come back another day then your way is quicker. If however you have to whack the E-Stop or need to call it a day half way through  then I am sure a RefAll to the switches is a lot quicker than having to find your parts zero position again, especially if its been machined away ;)
Also makes using a fixture a breeze as you can come back day after day and never have to touch off again unless you have changed the G54 (or whichever offset you had set)
Hood
Re: Drives falut out
« Reply #18 on: September 13, 2011, 03:09:17 PM »
Hood and Terry
 I am currently using what Terry is saying, if the drives fault then point of origin for the part is lost in some part cases i have to put the point of origin in the center of the material so i hope this makes my point clear as to how much of a pin it is to reset the point of origin gets machined away. As to Why my drives fault out it's a funny thing if i use the machine every day there seams to be no problem but if i work on another machine for a time and not the mach machine it fault's until it gets warmed up or something to this not sure i have checked and replaced still the same condition i am using gecko servo drives the machine has 120 volt motors so i am running them at half power they were at 100 volt's and i am running them because of the gecko drives @ 50 volts don't know if that would effect this or not.
Dennis

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Re: Drives falut out
« Reply #19 on: September 13, 2011, 03:34:38 PM »
Well I would say your best option is to fit accurate home switches as it will solve the PITA re-finding parts zero position over and over.
Now to your faulting, dont think it will be the volts as such as Voltage = Velocity and it is current that = Torque. Sounds almost as if there is something binding but as it heats up it clears, could even be your motors are only just capable and with cold way oil its just too much but as it thins with heating they are ok.

Hood