| The Breakroom > The Water Cooler |
| 3D printing |
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| picclock:
Hi PeterE The whole issue with the base in this design is a major one. As you so rightly point out, the y frame and gantry are all supposed to rest on a flat surface in order to achieve any sort of accuracy. Fixing them to something flat is the only way to consistency and rigidity. Once that is sorted the only other thing is the flexing of the gantry in the y plane which can be sorted by two side plates. These can also be used to ensure a true 90 degree angle for the gantry. As to the rest I will find out soon :scratch: Best Regards picclock |
| Swarfing:
I did not find the base to be a real problem. The longitudinal threaded roads fix to the cross member by aposing bolts which is very rigid. Also if you look at pics of the machine the back cross threaded rod fixes into slots on the side bracing pieces. words of thought here as I found the measurements did not compute for me and the rods ended up being short so measure this bit carefully before cutting. I screwed from the bottom of the base up through to the cross member and side braces. I managed to get him to send me a pic to show you more detail. Hope that helps. |
| efrench:
I used masonry bits to drill through a 3" thick granite surface plate. I did it outside with a hand drill and the garden hose keeping it wet. You definitely don't want to be breathing the dust. I made through holes, but the best way to do it is to epoxy steel inserts into the holes and keep them level with the top using magnets. IIRC, the Prusa i3 attaches the print bed at four points. If this is so, it should be modified to use only three points similar to the way a surface plate is supported. |
| picclock:
Hi EFrench I thought to do it much the way you said, except I was going to drill 15mm deep holes, fit a nylon bolt into a steel M6 spacer with a nut and washer on top. Then epoxy spacer into hole using washer as depth stop. Loosen nut and washer before finally set off and remove any partially set epoxy, then finally remove nylon bolt. I figured it would be a lot easier that drilling 30mm of granite. Print bed is not nice in the original design. Problem is that its not stiff and flexes with temperature as it warms up. Will try it with the original, cos its dead cheap and quick, but will likely replace with glass and heater pad, shame the cost is so high atm.. I seem to remember at one time you could get stick on heating elements for rear windscreens - something like that on a printer bed glass would resolve the issues of warping altogether (100C on a windscreen is a bit much I suppose :lol: ). Best Regards picclock |
| PeterE:
Swarfing, The picture attached shows a lot but not all of your setup. I notice that you placed the bracing triangles in line with the central opening and not in line with the outer sides of the upright. Any particular reason why? The Y axis motion parts are as you say connected to the upright using the two Y axis all-threads and nuts, and I can also see that you have made the upright with double thickness compared with the drawings I have seen - much along my thoughts as well, but did that create the "too short allthread problem"? Menaning that it affected the length for housing the Arduino below the allthreads at the back? You mention that you have secured the upright to the base plate using screws from below, but have you also secured the Y axis motion end parts as well or is the only connection through the pinching in the upright slots? efrench, Yes you remeber correctly. The design is to have the print bed secured at the four corners and I guess that the clipped-on glass plate is used to prevent/minimize the warping. How would a three-point securing improve on warping, that is less warping, in comparison? Would the glass plate make a better work of stabilizing the whole thing? picclock, Using glued in thread spares into the granite bed would work beautifully. /Peter |
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