MakerGear Forum

It's taking over an hour to get my bed to 60C.

Currently my bed layers are a thick heat safe glass (Pyrex?), MK1 heater, 4 rubber feet, dibond sheet, which is all elevated by leveling screws. And the ambient air is roughly 20C (cooler than some North Americans, but by no means cold.

The 4 rubber feet left an airflow gap between the heater and dibond, so i taped all around it to kinda make a bubble and that helps it heat up a little better.

Suggestions? Should I get a square of wool for this airgap layer? Should I make an under quilt for the Dibond sheet?

Some insulation will help, but I bet your MOSFET and polyfuse are nearly on fire right now. It's likely electrical.

Get a good fan blowing on your electronics, keep the bed MOSFET cool (and the polyfuse ... ugh, I hate those things). Make sure all your screws are tight, and the wiring to the bed is at least 16awg.

My laser thermometer says the heated bed connector is 45C at its hottest spot, so it seems your onto something.

It's possible the wire connector is heating up too much and causing resistance, preventing the bed from heating up?

I used the laser thermometer on various parts of the Arduino and Ramps and they are just fine thanks to the little fan blowing on them.

Edit: Thanks to a wool bed cover "quilt", it got up to temp in 27 Min.

WarMace wrote:the wire connector is heating up too much and causing resistance

It's the other way around: the connector is failing with a poor joint that introduces more resistance at that point. The platform heater has a very low resistance, so the failing connector limits the current, causing the slow heating you're seeing. Worse, the resistance in the failing joint acts as a small heater, which makes the connector fail even faster: a classic death spiral.

The power connections should be cool to the touch. If one isn't, then it needs repairing right away.

ednisley wrote:

WarMace wrote:The power connections should be cool to the touch. If one isn't, then it needs repairing right away.

Thanks, no more printing till I take the time to replace it.

Edit: Just replaced it. Bed heats up much faster. The (20?) gauge wire that is used from the connector to the solder points on the heater concern me, but it is probably factory from the kit.

Hi, This is really nice that you guided how to do this. But how to fix the quilt for the Dibond sheet? and how to place the quilt cover on it. And I am sure that I will get the all the necessary things easily in Melbourne, Australia.