Recommendations for large format heatbed

I'm in the build stage of a large format corexy printer, the print bed will be approximately 475mm x 475mm. How should I handle heating the bed. The commonly available options of silicone pad and/or pcb style don't seem to come in a large enough format.

You'll probably have to order a custom silicone heater, and pay accordingly. If the printer is going to be printing ABS and you don't want to wait too long for it to heat up to print temperature, you'll want about 0.5W/cm^2- i.e. about 1kW. Don't even think about using DC power- this calls for AC line power. You'll want to add a thermal cutoff and fuse to protect against SSR/controller failure and wiring problems.

My 300x300x8 mm cast aluminum bed has a 750W heater and gets to 105C to print ABS in about 4.5 minutes.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

For a really large bed it'd make sense to use individual heaters. You could ask for two 500x250-ish or four ( more common ) 200x200 silicone heaters. Then you can print smaller parts without adding too much "global warming"

Also ,you can try my decision for large heat bed. (450x600mm)


[forums.reprap.org]

Edited 1 time(s). Last edit at 11/12/2017 02:39AM by rarprint.

If you really don't want to go custom you might also consider a mosaic of 4 square silicone heaters. Perhaps you could find 9x9", I don't know.

This is the route I went for a 610mm square bed using four 12"x12" pads. I'd originally planned on an off-board closed-loop controller for each zone, but the pads are consistent enough that I've been running all four off one thermistor using the stock heater output (Duet Wifi fed to relays) without undue temperature variation. Separate controllers is a possible future upgrade but I haven't figure out a way to feed the bed set point from the Duet.

~Justine

Edited 1 time(s). Last edit at 12/08/2017 06:05PM by justine.haupt.

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justine.haupt
This is the route I went for a 610mm square bed using four 12"x12" pads. I'd originally planned on an off-board closed-loop controller for each zone, but the pads are consistent enough that I've been running all four off one thermistor using the stock heater output (Duet Wifi fed to relays) without undue temperature variation. Separate controllers is a possible future upgrade but I haven't figure out a way to feed the bed set point from the Duet.

The 1.20RC1 firmware for the Duet WiFi/Ethernet that I released yesterday supports multiple independently-regulated bed heaters.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

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dc42
The 1.20RC1 firmware for the Duet WiFi/Ethernet that I released yesterday supports multiple independently-regulated bed heaters.

Wow great news! Thanks for the update!

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justine.haupt

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dc42
The 1.20RC1 firmware for the Duet WiFi/Ethernet that I released yesterday supports multiple independently-regulated bed heaters.

Wow great news! Thanks for the update!

I slightly jumped the gun, because although the support is there, in the RC1 build there is a limit of 1 bed and 2 chamber heaters. I'll increase it to 4 bed heaters in RC2 which I expect to release later this week.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

FYI,

dc42 made said update. Happy multi-zone bed user here.

Edited 1 time(s). Last edit at 01/02/2018 11:51AM by justine.haupt.