Heated build platform idea.

Im constructing a new printer with a build size 700x400x200 and have been considering many options for a heated bed with miniumin effort.

I came across this for £35 so ordered one.
[www.ebay.co.uk]
they withderw the item and refunded (and the same happened again with a different supplier)
Now the only ones left are £140. Too much to see if it will work or not. I was hoping that 'cordless' means it will stay warm for a while when unplugged.
[www.ebay.co.uk]
They could be regulated with an opto switch from the 12v bed output of the ramps board.

Has anyone tried them?

Also (dont laugh) I was considering a water filled glass sandwitch heated with a towel rail element, possibly inside or with a circulating header system. There are silicone sealants that will do 250degC and I would use 10mm ali box as the frame and circulating duct.
My bed only moves in Z.


Any thoughts welcome

Edited 1 time(s). Last edit at 11/05/2013 09:03AM by Vince.

They appear to heat between 110c to 140c. This seems to be excessive temp for a heated bed, but I'm only guessing since I currently print with PLA with a unheated bed.

Joseph

I would stick the thermister on it somewhere and allow the ramps board to control the temp. If it gets up to 100 that should be ok. My mendelmax struggeles to get to 60.

I think that hot plate is using some quite new ceramic film heating technology, in which case it should be a very uniform heat. It may also be junk so its a bit of a gamble for £140.

I think it will be perfect so have emailed the factory.
See the sales pitch.

Is that substantially different to a normal plate warmer? If not I would think that you could pick one up easily from a charity shop for a tenner.

I think its very different from the usual hot plate /warmer that are bulky with either linear or circular elements inside and a metal top.
If you can understand the chinglish sales prochure it seems to be some sort of semi-conductor film between glass layers.

I am pretty sure my mother-in-law had something very similar to this. Really dont think it is new technology. How about this:-
70's warmer ?

Thats like the 12v pcb heat pads supplied with the mendelmax. It would probably actually work ok with the stuff taken off the ends. I thought a 70s warmer would be a tank top?

Edited 1 time(s). Last edit at 11/05/2013 11:52AM by Vince.

After much more research I think this may be my answer.
Heat mat stuck on a sheet of glass. Or two of them in my case.