Small space where the gantry meets the bottom plate [SOLVED]

Dear forum members,

At the moment I'm building the dibond kit. I've completed the first section by building the frame. I've made shure that all the white fixing blocks were flush with a flat surface, but now the frame is assembled I've noticed a small space between the "inner corners" of the gantry and the bottom plate (circled red in the attached picture). This gap is about 0.5 mm or so on each inner side. Is this tolerable? I've noticed that when I press on the underside of the bottom plate that the gap is reduced so maybe the bottom plate isn't exactly flat and is causing this.

Edited 2 time(s). Last edit at 09/20/2013 08:54AM by Nilez.

When I built my kit, I notized also some small gaps, but at another location and smaller.
I think this was caused by the elasticity / limited flatness of the desk, on which I built the M90.

At calibration of the bed with a gauge I can see, that the measured values change up to +/-50µm , when I put things somewhere on the desk.
A sturdy desk with a flat surface seems to be essential for our 3D printers.

I think you have just installed the fixing blocks too low on the gantry so they overlap the edge a bit. Loosen the two screws and push the base up to meet the gantry before tightening them again. There shouldn't be any gaps in the frame. Even if the panels were not flat they would be pulled together by the blocks.

Yes the machine needs to stand on a rigid flat surface. It doesn't have to be level but it needs to be a plane. If not the bed will appear to have one corner higher or lower when the other three are level. It can be fixed by putting paper shims under the end of one of the aluminium tubes until all four corners can be levelled.

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[www.hydraraptor.blogspot.com]

Thank you for the replies. I've managed to eliminate the slits except for a few. I've made sure that none of the fixing blocks overlap the edge of the surface of the gantry (or the other panels). Now there is indeed no more space between the gantry and other panels at the places where the fixing blocks are. At those places the panels are nicely pulled together. The only slits that remain are at places where there are no fixing blocks. The space allows room for a sheet of paper to slide through or at some points a folded sheet of paper. So were not talking about big gaps between the panels. I hope this is tolerable since at this point I don't know another way to completely eliminate them.

I don't really understand. The fixing blocks are not very far apart. Are you saying it is closed at the fixing block but about 50mm away there is a 0.2mm gap?

Perhaps the stays are fitted too low and are distorting the base? I can't imagine it being that rippled otherwise.

Edited 1 time(s). Last edit at 09/18/2013 05:17PM by nophead.

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[www.hydraraptor.blogspot.com]

Hi Chris,

Yeah that's what I'm seeing right now. Maybe I should disassemble the frame completely and do it again. Should I use new nylock nuts if I do? I have those at home.

I think all you need to do is loosen the screws holding the stays, re-align them and tightened them again.

There is no reason to use new nylocs. They do have less grip when re-used but they still have plenty for this application when used multiple times. They only have to be tight enough to not rotate due to vibration.

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[www.hydraraptor.blogspot.com]

Ok thanks, going to try that tomorrow.

That did it! Everything nice and square now.

Thanks