Expected ramp time for heated bed

[pmeyer]

I've got a new Rostock MAX v2, with the new 32A PSU (not an ATX supply). Works great. However, heated bed seems to take quite a while to heat (20 minutes). Way longer than my ultimaker takes. I'm using the stock bed with stock glass.

Before I start debugging: What is expected temperature ramp time to 80C with good PSU/connections?

Thanks,

Paul

[626Pilot]

How many watts is your power supply? The Viotek they ship is at least 400 watts. It should heat up to 50C in a few minutes, like five.

If you want yours to heat up quicker, throw a dishcloth over it. Works wonders!

You should be able to see the duty cycle in Repetier. If it isn't 100% during heat-up, that means you have some bad PID values and should run the autotune.

[pmeyer]

I believe it is 29A, 12V, so 360W. This is the new PSU (not ATX). Also, 12ga wire to the bed.

I can get to 50C pretty quickly. 80C takes 15 minutes though, and the one time I tried 90 (from 80), I waited 10 minutes and only made it to 86.

New Rostock max v2, open air, ambient is 69F, 20C. (STP)

If I have time today, I'll do a timed test.

I am using simplify3d, not repetier. I can try the internal PID auto tune.

Paul

[626Pilot]

If your v2 is like my v1, there's a sizable hole cut in the middle of the big piece of melamine that the heated bed and snowflake are bolted to, for the Onyx wires to route through. If you have a fan blowing air across the electronics downstairs, that air can escape through the hole and cool the heated bed from below. Try sealing that hole with some kapton tape.

I never take my heated bed above 60C, so I dunno much abut operating it at super high temperatures. Some people use the 24V Onyx with a separate 24V PSU and a solid-state relay to switch the power. I think that's a little complex, and I would try other remedies first.

[geneb]

The v2 uses a very small, offset hole.

g.

[BuckeyeVolunteer]

I have mine in the garage and it requires being covered to help achieve the bed temperature. I think the max v2 would benefit alot from a contained heated environment.