Displaced drawing

[raphmann]

Hi Dan,

here you can see that my drawing is displaced:
https://youtu.be/QCEz4rxuaUM

… an the result:
https://youtu.be/MQFPFpvj_Mg

[Dan]

It looks like the belt is slipping.

is the pulley tightly attached to the stepper motor?

As the pulley turns, do you see the belt skip on the pulley? If yes, count the teeth on the pulley. We have in the past received 18-tooth pulleys labelled as 20-tooth pulleys. Monsters!

[raphmann]

The Pulleys are tightly attached to the stepper motors and they
have 20 teeth. – No monsters.

With the orginal mount for the water bottles the belts have always
been skipping. Therefore I have bought two bearings that I use instead
of the wooden mounts. With the bearings there is almost no skipping.
But I say almost, because they are still skipping when the pen holder
is near to one of the corner.

[Anonymous]

Hi raphmann,

every skipping is fatal.
It should run without skipping at all.

In the beginning I had problems with the weight.
Try to add some weight, either to the Pen, or to the time belts right and left.

[raphmann]

Hi Joram,

do you know the weight left and right and at the pen holder?

How do you attach the weight to the pen holder?

[Anonymous]

[Anonymous]

Normal weight is ~100g left and ~100g right.

[Anonymous]

I think you need 200g on each side. Because of your construction with the wheels.
Try it.

[raphmann]

Joram, thanks for the video. I´ve tried 150g, 175g and 200g at each side. But
it still skips 🙁

What material do you use for fixing the pen holder at the left and right corner?
Is this a shirr?

[Anonymous]

Pay attention to which side it slides.
Does the pen slide up or down?
When the pen slides up, it needs more weight. Conversely: the pen does not need weight, the sides need.
I used a metal clamp/bracket as weight.

[Anonymous]

[Anonymous]

2.

[Author]

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