chain sag correctly didnât change much at all (28.09 to 29.12, within the range of other measurements changing)
how much weight did you add to the sled? that doesnât look right.
10 lbs more
hmm, I would have to dive into the math, but I would have expected that to make far more of a difference (especially based on how much the cut is distorted)
can you double check that you havenât had a chain slip? do you see the error mirrored exactly on the other bottom corner?
Itâs possible that some factor other than chain sag is responsible for the skewing, or part of it. Rotation radius error causes bowing of the horizontal lines, too large a value bows downward.
Iâll check the bottom right corner tomorrow morning. No chain skips. Both chains are measuring 1700mm when not connected to the sled
rotation radius is identical, motor spacing only changed about 1mm, z offset only changed around .5mm
I know this is a little late, but I am interested!
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Bottom right mirrors the error. I recalibrated with heavier weights again. Everything was the same except chain sag raised to 29. I added lighter weights and the squares are the sameâŚnot square. More weight does fix the L though.
As you can see in photo, 90 degree cuts get progressively worse towards very bottom corner. Instead of adding more pulleys and counter weights, we decided to try extending 10 foot header to 12 foot first. That was the easy part.
First problem was the calibration process wanted to use a chain to measure distance between the two motors, but the chain was not long enough. Ended up manually measuring between shafts and entered 3632 mm in settings.
Then we ran the set chain length program and it measured out what it thought we would need for a frame of 3632m. But as you can see in the photo, the chains have a couple feet between them, not able to attach sled.
Before I spend the time to do manual calibrations and measure everything by hand, is it possible my old Kickstarter chains are not the same length as the new kits shipping these days?
That step is for the 8â frame. Use the âNextâ button to extend the chains the amount that will put the sled at 0,0 and you can attach the sled.
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the chains are long enough for a 10â top beam, you need about another foot (possibly a smidge more) to use a 12â top beam.
the chains shipped with the kit are 11â long, 12â long will work for cutting but to measure the motors you probably want a 12.5â chain.
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EDIT: To clarify: itâs impossible to use a 12 foot header unless you also buy new 12.5 chains first. Letâs make sure NOT to say a 12 foot header is an option, unless we also say â12 foot header and new 12.5 foot chainsâ
After clicking Next, there is no option to Extend chains. Iâm stuck.
During Calibrate, I Extend chains, it spits out default length. Press next, it asks to zero in the Z.
During âSet Chain Length Automaticâ, I extend chains, it spits out default length. press Next and it says âCongratulations! Your chains have been set to a known lengthâ and I checked Calibrate.
Also, attempts to press âExtendâ a second time on initial screen results in motor making some noise but not doing anything.
(Sidebar: So far 12 foot header is good idea in theory, but doesnât seem practical . If this isnât easy for everyone, this route would not benefit the community. I donât want a unique setup for just me.)
I must have misunderstood which step of the calibration you were on. I assumed iot was this one:
Iâm pretty sure that the âNextâ button should do the same thing as the âMove to Centerâ button on that screen, extend enough chain to hang the sled at 0,0 based on the dimensions (distance between motors, motor height, rotation radius of sled) measured or calculated.
If your chains are still as shown in your picture above, the Actions/ReturnToCenter button. If the chains have been lifted from the sprockets since the chain calibration step, you could use the Actions/SetChainLength-Automatic button to run just that portion of the calibration sequence. Before doing that, though, take a moment to check Settings/DistanceBetweenMotors, Settings/MotorOffsetHeight, and AdvancedSettings/RotationRadius values.
If this doesnât help, could you attach a copy of your âconfig.iniâ file from your home directory? All the setting values involved are stored there, and could help troubleshoot.
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Or 5 feet/1.5ish meters and a couple repair links
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I believe we removed the âNextâ causing a move to center because folks werenât expecting it to move then and it was causing concern. To get it to move to center you now need to click the âmove to centerâ button
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Hey @ChuckC, I apologize. I have used a 12â header. I forgot to mention that I had to purchase an extra length of chain, in addition to master links to connect them to the current shipped chain. I ended up adding about 20 inches to the stock 11â chain.
It is not too difficult, but it costs $$ and takes about an hour of time. There are instructions online about how to break apart roller chain. You have to hammer one of the pins out of the chain. I was able to do it using a hammer, a drill-bit, one of the small nuts shipped in the kit, and a pair of pliers. Then you use a master link to connect it to the 11â chain.
Given the results shown in this thread, I donât see the default frame as being capable of cutting a full 4x8 sheet, no matter the calibration. The Maslow should be fitted with a 12â top beam, along with appropriate chain lengths, if it is advertised as a 4x8 machine. This tension system or heavier weights are also options.
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It is not too difficult, but it costs $$ and takes about an hour of time.
There are instructions online about how to break apart roller chain. You have
to hammer one of the pins out of the chain. I was able to do it using a
hammer, a drill-bit, one of the small nuts shipped in the kit, and a pair of
pliers. Then you use a master link to connect it to the 11â chain.
a chain breaker is about $15 on ebay, that makes taking one of the pins out
much easier.
Given the results shown in this thread, I donât see the default frame as being
capable of cutting a full 4x8 sheet, no matter the calibration.
remember, different people have different tolerance for problems. slowing the
feed rate will allow you to give gravity more time to move things, and so it can
be made to work.
remember, there are people out there with the original maslow âwingedâ frame
happily cutting away.
That saidâŚ
The Maslow should be fitted with a 12â top beam, along with appropriate chain
lengths, if it is advertised as a 4x8 machine. This tension system or heavier
weights are also options.
I agree that this is a good idea (just donât go too heavy or you have trouble at
the top)
To go slightly back on topic,
@Jacob
What lengths of elastic cord and paracord did you use? Where did you source the elastic?
Iâm building my frame with a 12â top bar, I was thinking of using your idea but tucking the cabling above in a couple of troughs like soâŚ
Think thereâd be any problems if I skipped the paracord and made the whole length elastic?
My guess is that ideally, the elastic should also be mounted on a ringâŚ
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Just looking at the design, it seems like some kind of tension needs to be present at all times to keep everything on the pulleys, so elastic everywhere seems logical. I am really interested in how this works, as I am planning on trying the 12â top beam myself. Please keep us posted!
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