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Chain lengths not coming out even during calibration

HI, I have just changed my top beam from 10’ to 12’. While I was recalibrating I noticed that when you extend the chain lengths to a known value that the right motor is extending the chain about 6" longer then the left motor. Is that normal? My thinking is that they should extend the same length on both sides. Second thing is that the chains are way to short to connect the sled to so I have to press the center sled button so that they will extend farther to connect the sled. After connecting the sled it seems to be about 2 inches to the left and 2 inches down from center. Is there a way to manually move center over? Thanks Travis

the two chains should go to the same length, that length (1651 mm) is not long
enough for a 12’ top beam. In settings (I think advanced settings), you can
change this value. If you double it things will work.

I would suggest that you pick a value that will put you at/near the center of
the workpice. It needs to be a multiple of 6.35mm, but that’s the only real
restriction.

David Lang

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No, I would expect them to be the same length at that point. After you press “Move to center” will they be the same length?

Down from center can be adjusted in the manner that @dlang pointed out, but left and right should be centered automatically (centered between the motors that is). I would try unplugging and re-plugging the motor cables to make sure there isn’t a loose connection somewhere.

@dlang Thanks. I’ll try to find that and double that number.

@bar Thanks for the help too. The chains are 6” different before and after move to center button is pressed. I’ll check all the connections and get back to you.

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Here is what I just found. If I press the move to center button again the left motor will move another 6” making it within 1/4” in length from the right motor. I’m not sure why you have to press it twice.

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I’m not sure why you would have to press it twice either. The only thing I can think of is that if the 12 volt power supply isn’t providing enough power the motor might not be turning fast enough to extend fully in time…but that is a long shot and I wouldn’t think too hard about it unless you have any other issues.

Let’s keep an eye on this and let us know if you spot any other strange behavior. Good work figuring out that pressing the extend twice fixed the issue for now.

@bar I adjusted the chain length when pressing extend number as @dlang suggested to 2032mm. Reset everything including ground control and ran calibration again everything seemed to work this time as I would expect. I’ve been attempting to make cut on pretty much the whole sheet that’s why I moved to a 12’ beam. But I found all of the x coordinates are pretty close but the y is 1/2” off over all in the center of the sheet. I started changing the distance between motors and then changing the height from work sheet to motor setting and seemed to be getting x coordinates closer but the y started getting to big. What other setting need to be changed to help control x and y? I’ve spent about 3 hours Saturday and 10 hours Sunday. Again, Thanks for all the help!!

Ps this is pretty much what I’ve been cutting. I’m getting ready to start building a boat and am planning on cutting everything on the Maslow!
image|666x500

To adjust that change the vertical motor offset in the settings. That number will move everything up and down. Changing any of the other numbers will cause your parts to become distorted when you cut them.

@Tjacobs713

Search the forum for the “List of sources of error” thread where you will find a whole lot to think about.

@WoodCutter4 I have read that thread 3 times. Sometimes I think I’m more confused then when I started reading. That’s why I’m asking for a little more direct help.
I measured distance between motors at 3636.9625mm motor offset at 501.65 and rotational radius should be 140. After doing calibration this is what I got.

Rotational radius and distance between motors seem to be a bit long. Is there calculation reasons for that or is an error?

that is going to give you distorted results.

one thing that you can try is the holey triangulation version of the firmware/GC

it’s got a different calibration routine in it that many of us are having better
results with.

With the stock calibration routine, you are are taking measurements, and then
the maslo is fiddling with the parameters until the calculations match the
measurements, so errors in the measurements can cause the calibration to be way
off.

when measuring, did you measure right side of cut to right side of cut or right
side of cut to left side of cut?

David Lang

@dlang I measured from right side to right side. I thought that was what it said.

that works, what’s important is to use the same side on both cuts.

David Lang

@Tjacobs713

I’m with you on that one. I haven’t had luck with manual calibration like others have. I have got good results with holey calibration.

@WoodCutter4 is there a specific link for installing what files need to go where to get holey calibration to work? I’m def willing to try it and I just read the whole holey calibration thread. Do I have to download python. Kivey. And pyserial all separately? I’m sorry for so many questions this is just all new to me

@Tjacobs713
Edit: moved holey comments and links to holey thread.