p1mrx

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[–] p1mrx 10 points 1 year ago* (last edited 1 year ago) (1 children)

I just tested this hook by hanging a 5 gallon bucket and gradually adding water. PLA 1 wall = 1710 g, 2 wall = 1178 g. The thing is, a 1.5 mm hook fails by straightening rather than snapping, so rigidity is more important than strength.

Edit: I also tried PETG: 1 wall = 1441 g, 2wall <998 g (failed to hold the empty bucket)

So the 1 wall hooks can support >40% more weight before straightening enough that the bucket slips off. That's more significant that I expected.

Edit2: Part of that 40% difference is due to friction; the 1-wall hook has a rough surface that makes the bucket less likely to slip off. But even with bluetack on the hooks, 1-wall has less deflection than 2-wall for the same weight.

Another confounding variable is the weight of the hook itself: 2-wall = (0.83g slicer, 0.78g actual); 1-wall = (0.95g slicer, 0.88g actual). I don't know if that extra weight is coming from density or volume, but either way the stronger hook is more expensive.

Sigh, reality is so complicated.

[–] p1mrx 7 points 1 year ago

Lock some calipers (with a rod sticking out) to 1.5mm shorter than the part height, compress it down onto a kitchen scale until the rod is just touching the platform, and record the weight.

That's just the first procedure that came to mind. I will try to think of a way to do a hook strength test today.

[–] p1mrx 2 points 1 year ago

I've literally never had this happen with a toilet made this century, but if you're buying one it doesn't hurt to check the MaP rating.

[–] p1mrx 2 points 1 year ago* (last edited 1 year ago)

If your printer has a touch sensor, then raising/lowering the entire bed has no effect on the first layer. The Z offset defines the difference between the touch point and the first layer.

I think most people calibrate the Z offset for 0.2 mm, and then never change the first layer height.

Edit: oops, this thread is a month old.

[–] p1mrx 1 points 1 year ago
[–] p1mrx 3 points 1 year ago

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[–] p1mrx 2 points 1 year ago* (last edited 1 year ago)

What exactly are your modifiers modifying?

Edit: oh, I see. A modifier lets you draw shapes onto the model instead of cutting planes only. That does seem like an easier approach.

[–] p1mrx 3 points 1 year ago (2 children)
[–] p1mrx 16 points 1 year ago

So you're saying it's technically a pirate ship?

[–] p1mrx 4 points 1 year ago

You can see in the photo that the wall is just above the waterline. It stays in that orientation until you disturb it enough to spill water over the edge, at which point it capsizes.

[–] p1mrx 3 points 1 year ago

It's not rocket surgery. Boats need more weight at the bottom than the top. If you put it in water and it leans, shift some weight in the other direction.

PrusaSlicer has a 'center of gravity' indicator that removes at least some of the guesswork.

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