FWIW, except for the CR20 as I haven't gotten my hands directly on it yet, I've replaced the build plates on all of our printers with solid 1/4" thick brass sheets and applied PEI sheets to them. The thicker PEI sheets available from more commercial sources, like Stratasys, seem to work much better than the thin stuff from Amazon/SeeMeCNC, etc. So far, it's been the best solution of anything I've found. The thicker PEI is also pretty expensive, but well worth it, IMO. We have glass beds for all of them too, but they don't spread heat nearly as well as the brass and nothing wants to stick to the glass without PEI anyhow, so...
The round brass sheets on our deltas seem to have come off of the waterjet that cut them with some bow in them, but the rectangles for the cartesian machine came out pretty flat. Eventually I plan to have them fly cut or surface ground dead level.
Also, FWIW, none of that is as expensive as it sounds. I bought a sheet of brass big enough for our Rostock and M2 from McMaster (who, surprisingly, was the cheapest source) for about $150 and having them machine cut was $50 (for both). In retrospect, I'd guess 1/8" brass would be plenty and the cost goes down dramatically there. I'd guess getting them fly cut, or ground, wouldn't be more than another few hundred, but I plan to have our in-house guys do that for me so I may never know.
We also have lexan enclosures on most of our printers. It's nice to be able to look in there without having to open anything up. I think the sheets (1/16"?) to make one for the CR20 were a couple hundred bucks. Surprisingly, ACE Hardware was the cheapest place to get them.
All said and done, I hope to have the CR20 printing some giant ABS parts, with reasonable reliability, in a big hurry, for under 2 grand. You can't even get anywhere close to that for less money when I researched the market before... just lots of fiddling around to get there.
The round brass sheets on our deltas seem to have come off of the waterjet that cut them with some bow in them, but the rectangles for the cartesian machine came out pretty flat. Eventually I plan to have them fly cut or surface ground dead level.
Also, FWIW, none of that is as expensive as it sounds. I bought a sheet of brass big enough for our Rostock and M2 from McMaster (who, surprisingly, was the cheapest source) for about $150 and having them machine cut was $50 (for both). In retrospect, I'd guess 1/8" brass would be plenty and the cost goes down dramatically there. I'd guess getting them fly cut, or ground, wouldn't be more than another few hundred, but I plan to have our in-house guys do that for me so I may never know.
We also have lexan enclosures on most of our printers. It's nice to be able to look in there without having to open anything up. I think the sheets (1/16"?) to make one for the CR20 were a couple hundred bucks. Surprisingly, ACE Hardware was the cheapest place to get them.
All said and done, I hope to have the CR20 printing some giant ABS parts, with reasonable reliability, in a big hurry, for under 2 grand. You can't even get anywhere close to that for less money when I researched the market before... just lots of fiddling around to get there.
