Moving the Arms to Fixed Points at Each Corner of the Carriage

Topic pursuant to this request from @dlang:

“This” being:

Moving to arms for the belts and for those
being at the edge of the carriage rather than using the router, or eventual
tool mount sleeve, as a hinge pin.

The math needed for calibration for this has been figured out, it’s just a matter of seeing if it is feasible to do something akin to that solver function I used in my code example in the actual calibration program.

It would be nice if this works out, because:

This greatly reduces the needed complexity in the design of the arms because
they would be able to have the motor mount in the center, which also removes
the issue of the belt being near the gears that keep chewing them up when
things go wrong, allows those parts to be much smaller as well, and doesn’t
have them being tied to the diameter of the router/sleeve anymore, which was a
problematic design restriction.

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First thing I need to do is look at the numbers to accommodate the belts not traveling in a straight line, rather a line with two bends, and apply the needed changes to the example equations I used previously to bring them in line with that, if necessary.

Then I need to rewrite the test I wrote in python in the language the calibration actually uses, if it isn’t already python. Definitely not worried about that, since it was the only time I ever wrote python.

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Excellent, this would be a perfect alternative to what I was considering.

Need a new sled design and that’s it, perhaps it would be possible to agree on a specific design we can carve out using the “vanilla” Malow 4.
My only addititonal hope would be a more rigid support beam assembly, if the new sled is made from any sort of half-decent ply this should be a non-issue.

Question:
Is the plan to make an alternative that uses the original belt drums, and to have circles cut out for mounting them on so that they can have a certain degree og rotational movement, or will the belt drums be fixed in position?

Expecting a design with fixed offsets for each belt drum in relation to router bit, as opposed to my suggestion with a circular rail where the router bis would be the center of the rail, like David said there would be some changes in the math involved.

Very exciting!

My plan is actually to eventually sand cast aluminum parts to reinforce the sled and replace the towers, as well as provide better mounting for moving the arms out.

In the meantime, it’d be a combination of wooden parts cut on the maslow and things I’ve 3d printed for testing. I don’t see a reason to replace the sled rather than just reinforcing it, at least at this stage.

The plan was originally to move them outward and put them on curved rails to use the current math but free up the router clamps to get much wider, then work towards them being fixed, but I’ve decided to just skip past that baby step since a new version of the maslow is getting designed which might accommodate that widening without the extra changes.

Currently, the plan is still staged:

  • First, create a way for the existing arms to be mounted at the corners for the simplest-possible upgrade with parts recycling so people just need to take the arms off, put the z carriage back together, put the corner mounts on, and put the arms in those mounts.
  • Second, redesign the arms to reduce their size and complexity, coupled with mounts for that new design.

Both of these require the same changes to the maslow’s calibration and runtime code, and to have both as a possibility would mean we would need to have an editable variable for how far from carriage center each point where a belt exits an arm is.

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@bar

Can you confirm where/which files on the github the code for calibration calculations is?

My venture through things just now didn’t bear any fruit (though I’m pretty sure I did at one point find the right file, for the original Maslow with 2 chains…lol).

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Carson Barry wrote:

Can you confirm where/which files on the github the code for calibration calculations is?

The calibration code is in the index.html.gz, so you have to go to the UI repo
to track it down.

David Lang

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If you want a version that’s easy to play with check out GitHub - BarbourSmith/Calibration-Simulation

It’s the same thing but with a UI and you don’t need to build the file and upload it to the machine to experiment

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