Straight line curves down at top of the sheet (solved)

Hi, Iā€™m not sure what you mean by quide pulley.Has there been a post on adding a guide pulley?

Thanks

Perhaps something like this?

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no more like this
pulley%20with%20repair%20washers
Topic
ā€œHow to Avoid Chan Wrappingā€

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I have the sewing machine bobbins from start, no need to replace found.

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I like that a lot
looks a perfect setup
going to swap them asap
Thanks

Or this? Sorry, bit of a shameless plug for my own stuff :stuck_out_tongue:

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And within a few minutes we have putt together the ā€œChain Guide Wikiā€. I love this place.

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Iā€™d be really careful about how you source those bobbins, at least wait until the owner isnā€™t home.

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Maybe ā€˜Maslowā€™ a sewing box in exchange?

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I think ->Jackie<- deserves a mention here. I was going through my scrap and/or collectables when she asked ā€œWhat are you looking for?ā€ and I explained that I need something round that can turn, to help guide the chains. She disappeared and came back with bobbins. Not so easy to change them now, even if I wanted to.

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and itā€™s obsoleted by running the chains acros the top beam :wink:

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That is correct. The new solid riser assembly eliminated any ā€˜snappingā€™ of the kit.
Sanding and polishing of all parts and washers got rid of ā€˜the rough edgesā€™, providing smooth move. Tightening the screws needs a sensitive touch, hard enough not to wiggle and loose enough not to block. Note that all my parts have a slight bend. For the horizontal arms I made sure they all ā€˜curveā€™ in the same direction while mounting. The vertical arms are mounted mirrored, so one would curve down and one would curve up. A little hammering with a rubber hammer straightened them.
After moving around with the arrow buttons, I would say I have nice and solid kit and am ready to explore the unknown depths of triangular kinematics.

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Not necessarily, itā€™s motor mounts can still extend beyond the beam, or the counterweight pull at an angle. Watching the way the chain meets the sprocket is still important, and positive control is not a bad idea.

looking forward to accuracy tests (and you should have received the new
kit today as well)

Iā€™d like to see you re-test the old kit with the full riser

possibly a second test using the new center bar with the old kit

and then finally with the new kit.

If you need me to send you money for plywood to cut on, let me know.

David Lang

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with the chains running horizontally, there is far less of a problem. the
counterweight is not pulling at nearly the same angle. The weigh just doesnā€™t
have the lever arm to move things out of place.

k

Wow, unexpected happy news :hugs:
Iā€™ve spent the the Friday sanding, LOLā€¦


The washers will be reused :slight_smile:

Shiny armour!
Edit: The sled is resting on a chair, so ignore angle of the kit!

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  1. Run an alternating CW/CCW pattern without bit (is to ā€˜bed-inā€™ the correct term?)
  2. Run new calibration with a warmed up Maslow. (Is there a recommended FW/GC combo? Iā€™m always on the bleeding edge ā€˜masterā€™)
  3. Run accuracy test
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No warnings in 1.03 or 1.07. Nothing in the logs. I put the weight back, as @MeticulousMaynard runns heavier then me and I have not seen this in the past. Going back to 1.02 now, to check

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The sag in direction of the cut at the top with F1000 and a 16.4kg sled is still there with 1.02, 1.03, 1.07.

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One thing that hasnā€™t been considered is your 12V supply. I had a similar issue and it was the 12v supply that caused the problem. I swapped in a larger supply and the problem disappeared. If you work out the physics, the chain tension is highest on the top of the sheet leading to the highest amp draw by the motors and if the supply is starting to get weak it will lead to strange problems. If it is a voltage problem, then components that can cause the problem are: the supply, the driver board or a bad motor or in your case one bad motor ( you could swap the motors to see if the problem reverses or changes to isolate out the motor as the issue). Have the motors ever gotten usually hot ( greater than 185 degrees for an extended amount of time, 30-45 min.)?
This may not be your problem, but it is worth considering.

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