Bed can't level any more, corner levels pivoting about the center.

I have a Reprap Prusa i3 rework, and it used to be easy to level, but nowdays, when i tighten corner, the other corner goes up. I just spent 30 minutes trying to level it. i got every corner perfectly level about 10 times, and while i did that the other sides of the heatbed would change by 2-3 millimeters.

The acrylic base of the heatbed, under the screws, seems to be a little bent and convex, is that possible it's even insulated with foam from the heatbed?

all the bolts of the RepRap are tight and i couldnt find anything loose. It just seems to be seesawing around over the center. i can't find the error.

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skynetprinter
I have a Reprap Prusa i3 rework, and it used to be easy to level, but nowdays, when i tighten corner, the other corner goes up. I just spent 30 minutes trying to level it. i got every corner perfectly level about 10 times, and while i did that the other sides of the heatbed would change by 2-3 millimeters.

The acrylic base of the heatbed, under the screws, seems to be a little bent and convex, is that possible it's even insulated with foam from the heatbed?

all the bolts of the RepRap are tight and i couldnt find anything loose. It just seems to be seesawing around over the center. i can't find the error.

If the acrylic frame is warped it's going to be hard to level. You probably need to pull the frame and check to see if it has warped. I'm changing mine over to plywood and eventually aluminum.

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Vanbot
If the acrylic frame is warped it's going to be hard to level. You probably need to pull the frame and check to see if it has warped. I'm changing mine over to plywood and eventually aluminum.

Thanks alot! it's so imprecise i just spent 30 minutes again adjusting it and in the end teh back end of the acrylic base was bumping into the back of the reprap frame and blocking the motors. I definitely need aluminium. one corner it's about 5-6mm lower than the other 3 levels, dammit. have to make an alu one.

What is the name of the heat bed mount i can't find any? I don't know if i can make one with a hack saw, perhaps even a square one for the prusa. will have to see.

Edited 1 time(s). Last edit at 05/16/2015 10:13PM by skynetprinter.

My reprap came with a 21 x 28 x 0.4 cm sheet of aluminium so i will machine that, and then i just need a thin copper sheet to place under the glass bed to tranfer heat outwards from the centre of the heatbed. mission.

Thanks for the motivation, here is a solution:

I took a mirror, waxed it with a candle, laid the old acrylic "tram?" on the wax, poured the molten wax around the border, cut out the outline using a rasor while the wax was warm and flexible for 5 minutes and took out the old tram.

My friend has 1 litre of epoxy resin from work for 2 euros and lots of glass fibre so i think we will be having a moulding session this afternoon.

Actually glass fibre and carbon fibre probably both have a better weight to rigidity ratio than aluminium. and easier to find. need straight fibres across the flexion paths though and thick on top and bottom of the tram surface.

Had a go with glass fibre. it's not dry yet and it's still a bit flexible, i hope i put enough fibre in. if you have a wood one, and coat it in carbon fibre and epoxy, it would be stronger than aluminium. just have to place the fibers on both sides.

Edited 1 time(s). Last edit at 05/17/2015 11:00AM by skynetprinter.

OK so the Glass Fibre is good and bad. It's Bad because my friend put toooo much catalyst, it warped totally when it dried too fast in like 2-3 hours, getting quite hot, the ends bent up by 5-10 mm so it's concave.

I printed on it, awesome, and then i discovered there is a problem... it bends according to heat, so when the bed is hot, the printbed is about 3mm higher than when it's cold, so it's totally unstable.

fortunately i have an aluminium plate i could also use. all in all a bit of a hassle.

Badly done epoxy without much glass fibrebends with heat changes.

The good side is that it prints awesome if i can calibrate it.

Edited 1 time(s). Last edit at 05/21/2015 06:18AM by skynetprinter.