this post was submitted on 06 Mar 2024
391 points (99.7% liked)

3DPrinting

15752 readers
126 users here now

3DPrinting is a place where makers of all skill levels and walks of life can learn about and discuss 3D printing and development of 3D printed parts and devices.

The r/functionalprint community is now located at: or [email protected]

There are CAD communities available at: [email protected] or [email protected]

Rules

If you need an easy way to host pictures, https://catbox.moe may be an option. Be ethical about what you post and donate if you are able or use this a lot. It is just an individual hosting content, not a company. The image embedding syntax for Lemmy is ![](URL)

Moderation policy: Light, mostly invisible

founded 2 years ago
MODERATORS
 

I upgraded two Prusa MK3s to MK3.9, and ended up with a couple of spare boards, stepper motors and a bunch of other things. So I decided to turn them into a Makelangelo clone!

Since the school I work at had these large standing whiteboards, I designed and printed corner brackets to hold the motors, as well as a base for the electronics.

1000006226

I'm still having trouble with the homing process, but very happy with the results so far!

I'll be posting the firmware and 3d printed files online soon.

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 2 points 9 months ago (1 children)

Hmmm, only if a second pulley was higher than the motor, I imagine.

[–] SchmidtGenetics 2 points 9 months ago (1 children)

You can use multiple pulleys and shackles to take the distance of the rope up.

It’s how they do it inside of machines as far as I’ve seen.

[–] [email protected] 2 points 9 months ago (1 children)

I still feel the distance they travel will stay the same. Except if I use a gear train.

[–] SchmidtGenetics 2 points 9 months ago* (last edited 9 months ago) (1 children)

Using #4 would allow you to move the pen 40cm for every 10cm of counterweight travel.

[–] [email protected] 2 points 9 months ago* (last edited 9 months ago) (1 children)

Ah yes, different sized pulleys would work the same as the gear train I had in mind. Thanks for the explanation!

Edit: on second look, it's more complex than that, as the weight is not connected to the end of the rope, but on a pulley.

[–] SchmidtGenetics 2 points 9 months ago (1 children)

Likely number 2 would be enough, would double the distance itself. You just need to attach it to the same corner bracket and have a pulley with the weight under it.

[–] [email protected] 2 points 9 months ago (1 children)

Yes. I would need to increase the weight on the pen too, though.

[–] SchmidtGenetics 1 points 9 months ago (1 children)

Smaller counterweight may work as well. Can take or add to either side of the equation.

[–] [email protected] 1 points 9 months ago (1 children)

I feel they're too light already 😅

[–] SchmidtGenetics 1 points 9 months ago (1 children)

Yeah I think you need to make it lighter?

Using the mechanical advantage for this would be for someone pulling on the rope to be able to lift a weight easier.

Your pen is the one pulling and counterweight is the weight, so you would need more counter weight or lighter weights on the pin. But too light would have its own tensions problems….

[–] [email protected] 1 points 9 months ago

Yes, you're right, don't know why I flipped that in my head, it's pretty clear on the diagram you sent me.