Looking to upgrade My heatbed MK2A-ALU 3mm Heatbed- Has anyone used? Recommend?

I am looking to upgrade the heatbed/printing bed on this printer. It has under 1 resistance which is a headache to use.
I have been searching online for any information I can find about the Heatbed MK2A-ALU Heatbed or one similar.

The only information I can find is that people have issues with aluminum heat beds warping after a few uses. These posts
do not specify if it was the 3mm thick version.

Any one use or have any recommendations?

Edited 2 time(s). Last edit at 04/15/2014 09:01PM by bladez.

It will warp i had a 3mm verson. Do not waste your money on one. It is said that you can print directly on the surface, don't try it. Get a good headbed pcb and mount it with insulation on the bottom and glass on top.

Has anyone used these 3mm Mk2b-ALU beds and managed to get them to heat to 110C? They heat slowly and don't reach that temperature, AFAIKT...

Hi, just got mine a few days ago, and as Wmtdanimal said, it warps - even cold it is slightly bulging in the centre, so you can't get a nice even surface. I'll probably end up putting the glass plate on top of it. If you like the idea of the alu surface, you'd be better off getting a 'plain' mk2a and slapping a 4mm alu plate on it. Or even carbon fibre...

I find that it takes over 15 minutes to get to 100C... anyone else? direct to 12V 40W switching power supply...

Are these beds the ones that do both 12V and 24V?

Could the people complaining it's slow be hooking the 12V up to the 24V pins?

Also, if you're using electronics that have a PTC fuse, you may find that at high currents the fuse is dropping a volt or so. You might want to look at replacing the PTC fuse with a standard in-line fuse. Measuring the voltage across the bed at the electronics end is also a good idea (as is at the board itself - you could be losing volts in your wiring).

I just got mine and was planning on running glassless with a PEI sheet. Haven't installed it but it looks flat. What sort of resistance are you getting? I've got 5.8ohms @ 24V and 3.2ohms (abit high? edit: realized I have to connect both 2 and 3 to ground, mine is 1.4 ohms) at 12V. I also got mine from RepRap.me which sells for a bit more than the ones from eBay china, so could it be a quality issue?

Edited 2 time(s). Last edit at 06/17/2014 11:56PM by genelmx.

Quote
paucus
I find that it takes over 15 minutes to get to 100C... anyone else? direct to 12V 40W switching power supply...

I'd suggest using a larger power supply.

I don't think that's reasonable, a normal MK2 printer uses only 16A going full-tilt... 20A should be enough. It probably needs to be thermally isolated beneath, to conserve heat, but we tried that and did not get much better... amazing how aluminum dissipates so quickly!

Those plates are garbage. I had one, ended up going back to a mk2 with a 6mm milled aluminum plate on top. Channel milled in middle of plate so thermistor could go in. Insulated bottom of heatbed and everything works fine. Will go from 19c to 120c in 8 minutes on 12v.