Heated build chambers are very useful when printing with ABS (apparently less so with PLA or PET, but I don't have any experience printing with those materials yet). Having a heated chamber is particularly important when the printer is in a cold basement, like mine is.
The Rostock community has come up with two common designs for heated chambers. I went with
jfettig's design, mostly because it looked fairly cool.
It's designed to take 1/8" Lexan (polycarbonate) sheets. Unfortunately, the dimensions are kinda screwy. The vertical dimensions are all 28.5" tall. The horizontal dimensions are 5.25" and 12.75" wide. Lexan is sold in sheets whose dimensions are multiples of 12". So jfettig's design results in a lot of waste polycarbonate. Which is relatively expensive. I looked around a bit, and it would cost around $200 just for the Lexan sheets, never-mind the angle pieces and shipping.
While I was looking for a cheap source of Lexan, I printed the brackets for the heated chamber from Jfettig's design files.
First the top corner brackets, experimenting with orientation and "
helper discs" to try to control warping/curling:
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| X-tower top bracket |
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| Y-tower top bracket |
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| Z-tower top bracket |
With those three brackets printed, I gave up on being able to print non-warped parts without a heated chamber, and still didn't want to pay out for Lexan.
I picked up some rigid styrofoam insulation with aluminum lining for about $5 and set up a rudimentary chamber:
I didn't have a heat source yet, but I did have a temperature controller with a temperature display (the red LED readout sitting on top of the printer). I proceeded to print the bottom brackets, still experimenting with helper discs,
rafts, and orientation:
Incidentally, printing large, flat objects like these on rafts is terrible. They printed without warping, but I had to use a wood chisel to separate the part from the raft, and often left some of the part on the raft (or vise versa) anyway. I also managed to give myself a nice little scar on my left pinkie finger by being careless during this process (It was the first time my 16-month-old son saw me bleed - kinda freaked him out a bit).
During this same period, I printed off an external extruder mount (
we'll get back to that later) which I printed with no raft or helper discs, and turned out with no warping - likely because it was much smaller:
I assembled the brackets to the printer's frame, and cut the foam insulation to size. I installed a
mount for a halogen bulb, controlled by an old dimmer switch I had lying around and the
temperature controller.
And there it is! A working, cheap, heated enclosure. The interior gets up to 50C with one 150-watt halogen bulb.
Later on, I used metal tape to cover over the gaps between the insulation panels. The metal tape is folded on itself and attached only to the smaller corner panels. This way, the panels can be completely removed (and replaced) from the printer easily.
I cut a hole in the front panel and covered the hole with a small, $12 piece of Lexan:
Unfortunately, I would have an unrelated failure before I completed my first print with the heated chamber. But that's a story for
the next post.
In the future, I'm going to have at least one (probably two) webcams on this printer so I can check progress without going down to the basement. I already caused one cheap USB webcam to fail after it spent an hour inside the chamber (it turned back on the next day, after it had cooled down). I also want to figure out a way to fit the panels on more securely, without relying on blue painters tape. The bracket design was intended for 1/8" plastic panels, not 1" foam insulation. That may require me to design and print my own brackets. (
Update: for the time being, I just used a chisel to knock off the outer lip of the bracket. Not very pretty, but functional enough with the addition of binder clips).
