Yeah, I got that one to work. I just thought they might be different videos. Thanks!
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Yes Sir @mooselake !! In the ortho reconstruction business and almost got my big toe whacked off by a 25lb instrument tray that fell from head height bout a decade ago. So, I found these clogs that are good for standing all day and have steel toes to boot. Havnt worn anything else to work since😜
Will be raining here in warm and humid south Louisiana… Low 80s for the highs for the next few days and trees are already blooming! All the stores around have their spring yard shipments out and ready
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@clintloggins, the cut seems to be wandering in the direction that the bit would pull it.
@gero’s cut was horizontal so it was easy to check in the log file to see that the motors thought they were in the correct place when the bit was straying. Do you have the log file that goes with the arced cut, and the .nc file? Was the home location 0,0 for the cut, or was it offset to a clean spot on the sheet? It will be harder to check, but it could give us a clue.
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This time of year I occasionally wonder why I left Houston. OTOH summers are a lot nicer.
I’m an orthopedic reconstruction customer, right rear TKA about 5 years ago. Also prone to dropping things on my feet and wear safety toed footwear most of the time…
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I have seen this before, I thought it was a calibration issue before but I think the left motor wouldn’t keep up with the right motor. I notice it only happened going right to left. If you watch one of the movies shows the sled move along the top and it slowly goes down as it moves left and suddenly jumps up near the end. In the other video it goes from left to right and stay flat across the top.
https://drive.google.com/open?id=1DdrU9igwtY_A-4fV0ncgpafxgWUIqg-g
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@blurfl I will check for the log when I get home. Also, will upload the NC file and as for the start location, I set home in afferent location. Although, as I wrote before, when prompted to recalibrate when I went to 1.06 I did so. The 0,0 location after calibrating was somewhere around 9 inches low. When I pressed finish I didn’t have the upward zag to the left then upward zag to the right as I normally do when calibrating(this would get me to true 0,0) this time it was 9 low at 0,0
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My question about the ‘Home’ location wasn’t clear. Did you need to use ‘Define Home’ to make the cuts in a fresh part of the sheet? I guess that info will be in the log as well. I hope you’ve got the log, I love a good mystery 
I did define home in a new location for a fresh-cut… That was right after I had auto calibrated the chain
The slow down is related to this issue:
I had it in my mind that the issue was only causing a change in speed, but it looks like the position that the kinematics are reporting is off too!
From watching the screen the machine thought it was following the line the whole time, but was really way off. I think this could be a kinematics issue!
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Thanks @bar and @krkeegan , I know y’all are on it!!! I didnt switch back to 1.04 yet, wondering if I should? Atleast til things get sorted out.
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I don’t think the #388 bug is the cause. This bug is present well prior to v0.90, I think it may always have been there and we just didn’t notice. Plus, I am not sure this bug affects triangular kinematics which I see @clintloggins is using.
@clintloggins I would be interested to know if changing to v1.04 helps, it would certainly limit where we need to look for a bug.
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After a little poking around I agree that it is not the same bug. I can’t get #388 to replicate when using the triangular kinematics which would seem to rule it out.
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@gero is having some good luck relating the issue he is seeing to the feed rate:
Would you be able to test to see if you see the same increase in accuracy at a lower feed rate that he is so we can try to determine if this is the same issue or a new one?
Will do it when I get home👍
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Is this a good idea or is my thinking wrong to use counterbalance. Putting 35 pounds on each chain instead of bungy cord would assist the motors when they are pulling and possibly improve the speed.
If you put so much weight on the slack end of the chain that you exceed the tension on the sled end of the chain, you would have gear backlash issues to deal with as well. The challenge here is that with the typical Maslow design, the minimum sled tension can be quite low (less than 10 lbs), so to avoid backlash issues your slack weight would need to be less than that.
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currently, the stretchy cord provides the most force when it’s needed the least,
and most likely to cause problems.
I think a weight would improve things, but there isn’t a good way to do it on
the traditional vertical slack frame design. The new design where the slack is
across the top beam opens up new possibilities.
I also think 35 pounds is going to be far too much weight for this as well,
start light and add just enough to keep the chains up out of the way.
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I tried to measure the backlash with my dial indicator and it seemed to be in neighborhood of .01". I might give it a try tomorrow. I have a Unistrut frame so it would be easy to modify.
Took the router out lowered the feedrate to 20 and followed the same path… I went back to 1.03, thought I was 1.04 but wasn’t, and all is great.
Not sure if anyone is on periscope but going live.
Search Maslow CNC
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