CS wrote:Sweet! Whatcha making in the video? What stuff have you made?
Some times I stare at my 3d printer for an hour and half. Thanks for posting the full, unadulterated, video. jk
First I made a keychain, and then on the video was a filament guard that clipped on the edge of the 0.25" wood I used for the walls. It was live streamed over Youtube, which made a handy recording for me, so I figured you guys could jump around it wherever you wanted lol.
wyz2285 wrote:How did you wire/setup the manually controlled hotbed? I got
this in the mail today but I'm not sure how to install it yet.
I'm making a shelter for my printer too, but from acrylic instead of wood and I'm planning on install a heater inside so the temperature is constant.
I wired the manual switch simply to preheat the bed before the Raspberry Pi boots up and connects to the printer electronics. Here is how I wired it:
Normally, the heatbed would be connected directly to the Printrboard (printer electronics) and would be powered by that. I found it took far too long to heat up, so I added the relay. The current that would normally be applied to the heatbed is instead applied to the relay coil. When the coil is energized, it allows the larger 12v current through straight from the power supply to the heatbed, drastically reducing warmup time. The manual switch is parallel to the relay, meaning if either the manual switch is on OR the Printrboard calls for heat, the heatbed will be energized. Once I connect with the printer and set my heat bed temperature, I turn the manual switch off and let the firmware run the temperature, otherwise it would overheat. The LED turns on whenever the heatbed is turned on, whether from the manual switch or from the printer electronics.
To connect without the manual switch, which isn't really needed, you would connect the heatbed and the included thermistor (which should be stuck to the underside of the heated bed) to your printer electronics on the appropriate pins. The thermistor is to read the temperature of the heated bed.
jrrdw wrote:Correct me if i'm wrong but the idea of having a heated bed is to keep the print from moving around. If you heat up the entire unit the print will remain to soft causing sags and other funky distortions....
Wouldn't it?
Yes, the heated bed is mostly to get the first layer of the print to stick. However, if you print with ABS like I do, you would find its very sensitive to temperature. On larger prints, it has a tendancy to warp and pull up from the bed on sharp corners. By increasing the ambient air temperature (inside my enclosure, it only gets up to around 40 degrees C with no heater) it reduces the tendency for ABS to warp. You might find that the heater is unnecessary, the heated bed supplies plenty of heat and would heat a small enclosure nicely. Bringing the temperature up too far (60 C +) would result in the actual printer parts softening and warping, which would be bad.