Something Changed Over Night

[yoopertool]

Ok, I am going to try to explain what happened to the best of my abilities.

I have had Mach 3 installed on my router table for about 2 years now and absolutely love it. I have had no problems until now. I am milling some simple 1in x .068in slots in a piece of material (hundreds per plate). To do this I am ramping down at 3 degrees using a .063 endmill. I ran a few pieces yesterday and they turned out great (within about .002" on them all). Today I started the machine and computer back up and started making some more parts. What is happening is that the slots arent coming out a full 1" long (more like .970). I can see where the tool starts the ramp, but it just does not seem to complete the entire move and stops short. All the slots did come out consistent though.

I didnt change any settings or anything like that. The axis are all ball screws and linear ways which are all very smooth. The computer wasnt used between me running parts and isnt hooked up to the internet, so there were no wierd windows updates messing anything up.

I tried playing with some things to fix it and the only thing that helped a little bit was slowing the feed down to 30%. I just dont understand what happened. I have never had anything happen like this in the hundreds of hours I have been using the machine. Any help would be appreciated. Thanks!

[ger21]

Sounds like you may be in CV mode, but were in Exact Stop mode before?

[yoopertool]

You are correct that I am in CV mode, but I have been for quite some time. I had tried changing it to exact stop but there was no improvement on the results. It almost looks like i have a glitch going on with the software on my computer. I might just re-load the software and see if that changes anything. Does anyone have any other ideas? Thanks again for the help.

[bill south]

If you are using steppers and your axis is beginning to bind, you may loose steps. Check the mechanical movement for binding.
Hope this helps.
Bill

[Crevice Reamer]

I don't know in which direction you are cutting the slots, but that axis is where the problem lies. Check everything for that axis, beginning with steps per inch, and down to connector/pulley set screws.

CR.

[ger21]

I'm going to guess that maybe a coupler is loose, or something like that.

[yoopertool]

I have already checked for binding and for lost steps. What I did to check for lost steps was

1) run the program
2) MDI it back to the 0,0 position
3) Check that the location of 0,0 didnt move

I also checked my couplers for play and didnt find any. In the next day or two I think that I will reload Mach 3 and also go through EVERYTHING on the table and see if anything changed.

[ger21]

When you cut the parts, does the DRO show the correct position when it comes up short?

[yoopertool]

I havent checked that yet. The machine moves pretty quick, so I couldnt really read it accurately. What I could probably try is running it in single block mode. This way I will be able to see if it is going where it is supposed to. My question is, if while running in single block it goes where it is supposed to, but it still doesnt work right in full auto, what would that mean and how would I fix it?

[ger21]

Exact stop mode should get the job done for you.

[yoopertool]

Well, I did some more work on my machine and now it works. The problem is that I dont know what fixed it. I went back through all my couplers and pulleys and tightened them all, but none of them were loose. When I built the machine I used Red Loctite on EVERYTHING. I can now run my parts in both CV mode and Exact mode. Im just not sure if I did anything to fix it or if this is going to be just an intermittant problem. I guess that only time will tell. For now I just hope that I can get a few jobs out before anything else happens. Thanks for the help guys and hopefully this problem is solved