Very large heated bed (400x400mm)

I am currently building 3D printer with a work area of 400x400mm. Printer is designed by me and made using T-slot 5 profiles and ballscrews.

The biggest challenge I have is heated bed. I want to have one like MK3 ALU-Heatbed Dual Power.

Any one know where to buy/custom make so big bed?

Regards,
Martin

Easiest way is to use an AC-powered silicone or Kapton heater pad attached to an aluminum plate, controlled with an SSR.

Other options are listed here.

Get an 18" square ceramic tile for about $10. Get some of the cheap diamond drills and a circular diamond blade for a hand grinder. Drill a row of through holes along two opposite edges about 6mm in from the edge. On one side connect the row of holes with a slot, String nichrome wire back and forth between the rows of holes. Set your glass or another ceramic tile on top of the wires and power it off the mains. If you are worried about a short on the bottom where the wire is in the slots, fill the slots with muffler repair putty. I have the tile but I haven't tried putting it together yet.

Quote
NewPerfection
Easiest way is to use an AC-powered silicone or Kapton heater pad attached to an aluminum plate, controlled with an SSR.

Other options are listed here.

You saved my day! Thank you. This looks like a good idea.

I just have to figure out how to connect SSR to Rumba board and I am at home...

I found a supplier in China for 24V 400x400mm heated silicone mat.
[www.aliexpress.com]

What do you think?

Edited 1 time(s). Last edit at 03/26/2014 06:34AM by MartinAM.

To get the same energy density as a 120W 200x200mm bed with a 400x400mm 24V bed, you'd need a 120W*4/24V=20A supply.

It could work, but switching 4 amps worth of 120VAC might be better

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MartinAM
I just have to figure out how to connect SSR to Rumba board and I am at home...

Easy:

I see DaveX.
So it is better to get e silicone mat for 230V then 24V.

NewPerfection : Thx for schematics.

I'd expect that standard higher voltage heating equipment would have more product testing than special-purpose cheap 12 and 24V stuff, but do be careful with the dangerous higher voltages. Make sure its on a GFCI and treat it carefully.

20A at 24V isn't risk-free either.

Yes I will do that. on the other hand, my CNC router has 80V 24A..