Just to double check everything give the Test Motors/Encoders a go so we are 100% sure we’ve got a clean bill of health mechanically
All 3 motors will run in both directions when I push the test motors/encoders.
I unfortunately have to leave to go home and leave this maslow in a broken state but I have my own at home and will see if I can’t test this problem on that machine to see if this problem persists there with a completely different setup.
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OK, it’s good that at least we know it’s software issue.
I think the next step is to get to a known state by wiping the Arduino’s memory and resetting GC to the default settings by clicking
Actions -> Wipe EEPROM
Actions -> Reset settings to defaults <-- This will close GC and make a backup of your old settings if we want them back
Actions -> Set Chain Length Manual <-- This will trick the machine into thinking the chain length is already set
After doing that we should know where we stand software wise.
I have gone through this wiping of the software I assume that I need to go back and flash the arduino? Because currently after doing reset settings to defaults I do not connect to the board anymore.
You will have to enter the com port back in on GC settings
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Thank you, I realized that after I went back in again looking at setting. I am now able to actually turn the motors in the correct directions and they are even going 5 and 1 degrees in the alignment setup. The motors are also spinning the correct directions to extend the chain for measuring between motors.
Is there anything that I need to do differently for the calibration process? I saw that in 1.13 there is another chain calibration for stretch or something, should I run that or just do all the normal steps first?
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Compute chain calibration factors are in a fact finding state. If you run this, you will want to zero out your chain tolerances before you run a cut. Post your findings after running the Compute chain calibration factors so they can be used in adjusting future versions of GC.
After going through the Calibration process after wiping everything I extended the chains out but then when I told them to go to center I got this error.
I went to the next step and then the Z axis was not able to be controlled even when I said that it was supposed to be there, I decided to skip the rest of the steps and do the z axis manually from the main screen but once I skipped through and went to close the calibration process all of GC crashed and disappeared.
Edit: After restarting GC I was able to manually define Zero on the Z axis from the main screen and I will next try to go back to the calibration page to correct for chain sag.
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Great! It sounds like we are making some progress albeit with setbacks.
I wouldn’t mess with the chain sag values right now. That code is still pretty experimental and we have so far found that it usually reduces accuracy instead of increasing it. The best results so far have been with the chain tolerance values set to zero.
I would give the regular calibration process another go to see if the sled not keeping up error happens again.
I got through the entire calibration process and then was doing the test cut pattern with the 4 lines and the 4 boxes when I got this error.
It did the bottom left square pretty accurately, it looks like to be 3 11/16" in both dimensions (it may be off by 1/32 or 1/64 but I do not have a good enough measuring device) Is that the correct size?
Also, with this error, do I need to try and recenter my sled or do I need to go through the chain length process again because of the error?
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You should be safe to press stop to clear that error, nothing else is needed. I would like to track down the root cause of the error.
It usually means that the motors are not getting enough power. Are you using the regular power supply? Is the sled heavier than normal by any chance?
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The motors are using the stock power supply.
I had not thought of that, I had added a little more weight because I saw it tip once and another time I saw it start to buck because I thought it did not have enough downward force. If I were to lower the weight should I then potentially raise the ring up slightly? It is currently just above the middle joint.
I have now lowered the weight by probably 15 lbs, it is probably 15lbs of counter weight now plus the stock router and ring (I wish I had a scale)
Finally, I found that my chain had actually wrapped around the sprocket and gotten tangled which I am assuming is why it had so many issues and I am lucky that it wasn’t worse. I think that this is a problem with the chain tension? Would you suggest I look at anything else?
Edit: for giggles I went ahead and did a 10" circle in the middle of the work surface and I got about 1/32" under top to bottom and about 1/16" over left to right, so MUCH closer tolerances than my last cut for a sled but still a little off. But again, SOOO much better.
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Progress!!!
I think you are on the right track and looking at all the right things. I can’t think of anything else to look at specifically, but it sounds like you are adjusting the right things.
The one bit of advice I have is that the weight of the router will effect the calibration process so you might want to do it again. If you don’t want to go through the whole process you can skip to just the last bit which is what you need by clicking Actions -> Run Triangular Test Cut Pattern
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Gotcha, that makes total sense, I did that decent 10" circle with the same calibration but 1/2 of the counter wright on the sled so am I to assume that this will more than likely change chain sag? Is there anything else I should be looking for a change in when I go through the calibration process again?
Thanks for all of the help. Love my maslows!
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Chain sag is what I would expect to change also 
The motors are using the stock power supply.
I had not thought of that, I had added a little more weight because I saw it tip once and another time I saw it start to buck because I thought it did not have enough downward force. If I were to lower the weight should I then potentially raise the ring up slightly? It is currently just above the middle joint.
I have now lowered the weight by probably 15 lbs, it is probably 15lbs of counter weight now plus the stock router and ring (I wish I had a scale)
IIRC. the bricks are in the 5 lb range, so you are probably still a little
heavy.
Finally, I found that my chain had actually wrapped around the sprocket and
gotten tangled which I am assuming is why it had so many issues and I am lucky
that it wasn’t worse. I think that this is a problem with the chain tension?
Would you suggest I look at anything else?
damaged chain can add to problems, make sure the chain flexes well along it’s
entire length and doesn’t have any sideways jogs.
David Lang
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Will do! Thanks for all of the shared knowledge.
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Sorry this has taken so long to get back, but unfortunately work got busy.
However, I have been able to do the calibration testing a few more times and I believe that between that and getting a little better chain management I have fixed a lot of the issues. I was able to cut one of my 10" circles and get it within about 1/16" between the top/bottom and left/right. After I got this result I was able to cut a new sled and that produced about the same results as the earlier circle about a 1/16" or so difference for the new sled.
I think installed the new sled and have re-calibrated and cut the 10" circle again and it appears to be about 1/32" off in the left/right but pretty dead on in the top/bottom.
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That’s great news, thanks for updating us.
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Where do we stand on this? I’m wondering if I need to get a new set of chains . Mine are somewhat twisted after being abused by getting wrapped on sprockets and I’m still not happy with where I am on calibration. I seem to be generally 1/16th of an inch off in vertical.