Carving not centered on board

[SharonB]

Having lots of problems putting an A-machine back together. Even though it only has 28 hours on the cut motor the whole machine was filled with sawdust (motors, sensors, switches, etc.). After about four days of cleaning, I ran all the sensor checks and everything seemed to check out. I started a small project and it carved ok but pattern was about 1/4 inch off center.... towards the keyboard side. I can not find where this issue has been addressed on the forum. I would like advice regarding this matter. SharonB


PS: A second problem arose after installing the cutting bit (to cut out pattern). The Z-track went to the keyboard side and hit fairly hard causing an error. I have read several discussions posted here on the forum and will be checking this out tomorrow. But might be back later for more advice.

[henry1]

maybe post your project might help or did you centered on the program it self

[bergerud]

... pattern was about 1/4 inch off center.... towards the keyboard side...

Normally I would say check the Y offset. But, you say the truck crashed into the keypad side after the bit change. That sounds more like the y belt slipped, That would explain both. The belt could be slipping at the bit plate thwack.

[DianMayfield]

Sharon, this might be out in left field.. but when I assembled my A machine last time, the dust diverter cup did not end up properly seated on the side. It was angled out towards the truck. The truck ran into it with some force and noise. Took a while to figure out what the heck happened!!

Never had this happen with my C machine.

[Digitalwoodshop]

Since the machine hit the keyboard side hard that tells me it lost a few steps and hit before it expected... AND you said the art was off set.... That too is a Y thing...

I bet the Y encoder is dirty or the clear disk is loose...

AL

[cestout]

I was going yto say check the Y calibration, but the Y belt slipping sounds more likely. Was the pattern off center toward the keyboard side? That is the way it moves with a grab on the climb cut.
Clint

[SharonB]

Just came in from the shop. After taking everything apart (not the encoder though) and started to put it back together I noticed that, when the Y motor pack is installed like the video.... with the motor mounting flush with the case it drops the belt lower than the right side. This, to me, would put the whole system in a bind when coming to the left (keyboard) side. As installed now the motor "case" is about an 1/8" higher than the machine case (if that makes sense). The belt is now fairly even from side to side. The 14 pin cable will miss the fins on the motor by about an 1/8". I haven't got to the stage yet of testing but I will also check Dian's suggestion of checking dust diverter cap when putting the lid back on.
Probably more questions to come later but I have to get ready to attend a community gathering this afternoon. Keep the answers and questions coming as this is certainly a learning experience for me. And, because I have just been given two more machines that needs work (besides this one and my own machine that is down with a bad cut motor) I should be a fair mechanic by the time all things are said and done. Thanks everyone Sharon

[Digitalwoodshop]

Y look what I found in the "Y" Encoder....

GOOD Job on the repairs.

On a side note unrelated... Lawrence is back from his Post Military Retirement Road Trip and is posting on Sawmill Creek about his new CNC.

AL

[SharonB]

Thanks for the pictures Al. After seeing your pictures I just might spend the extra time taking the encoder apart because of all the dust I've found in all the other components. If I was going to conference this year I'd ask for a class on how to take all the motors apart and diagnosing common problems.

PS: Thanks for the information on Lawrence. Will have to check out the Sawmill Creek posts and see what he is up to now days.

[SharonB]

I just seen this on FB and thought it was appropriate for this thread:

Parts Specialist
We do
Precision guess work
Based on unreliable data
Provided by those of
Questionable knowledge.