Print Bed - Heating Issue

[LoefflerG]

Recently switched from PLA to ABS and discovered that the print bed will not heat past 100-105C... it is extremely slow heating from 70 to 100, maybe 10-15 minutes even with paper towel rapped in aluminum foil laying on top of the bed.

Just now I got it to go from 100 to 105 but it took almost 10 minutes. I would guess that the bed could heat up from 20C to 110C in less than 10 minutes... am I wrong in that assumption...?

Has anyone had any issues with the print bed heating and if so, what information can you share.

Thanks,
Guy

[ned73]

The power supply is only 30 amps so it will take forever to heat for ABS.....

[bolsoncerrado]

Whats the ambient temp on your place?

Also try to surround the printer with cardboard so heat takes longer to go away...

[McCrapShot]

I'm having the exact same issue trying to do ABS, though I've been unable to break 97C. However, my apartment is around 20C due to winter. Tried doing a print with the bed at 95C, didn't turn out great. Top was fine, but the bottom layers warped and lifted off the bed, fortunately I still had enough adhesion that the parts didn't move. Gonna try using a heat lamp tonight. I'm hoping if I can get the ambient air around the bed up over 30C that the bed may be able to hit 110C. We shall see.

[LoefflerG]

...thanks for the information.

Guess I'm looking at getting a PCB heated board to help increase warmup time.

Just ordered this one off eBay: http://www.ebay.com/itm/321120664256

I'll let you know how it goes. I've now got a few upgrades/changes I'm making to the factory stock 200 version.

[McCrapShot]

Well, heat lamp still wasn't enough. Barely made it to 100C before it stalled out, unable to get any hotter. My next idea was to try and insulate the bottom of the heatbed. It's lifted off the platform and exposed to air. My hope is that if the bottom were insulated then the rate of heat dissipation would be reduced enough to be able to get the bed to 110C. My concern is that whatever material I use would need to be able to withstand the temperature on the bottom and have high enough electrical resistivity to prevent catching fire or causing a short. Fiberglass seems like it would work well. I measured the voltage output to the heatbed and it appears to be 12VDC, which should be perfectly safe in contact with fiberglass.

Alternatively, it might work just to encapsulate the air pocket underneath the heatbed and use the air trapped there as the insulator. I'd feel a bit better about this option but it would be a bit trickier to do.

[bolsoncerrado]

...and surround the printer with "something" too.

[CountZukula]

For reference: I can't get my bed above 80 degrees celsius either, but managed to get some good prints with ABS (235 degrees extruder head). I had some troubles though, with adhesion to the bed, but got it working after some cleaning with acetone, getting the head really close to the bed when calibrating and roughening up the kapton tape with some 500 grit sandpaper (first sandpaper, then acetone cleaning).

-edit- oh yeah, and i disabled the fan on the extruder head, so it doesn't cool so aggressively making the warping less severe. still experiencing some getting-unstuck-problems once in a while, don't know what to check next :\ maybe my bed is uneven...

[LoefflerG]

...while I wait for the newer style PCB Heat Board to arrive ... I ended up using 10mm brim with blue tape attached to the brim once it started printing the actual piece... carefully placed the tape over the brim and onto my kapton tape.

[bolsoncerrado]

What takes you to choose ABS over PLA? PLA seems less sensitive to temperatures while being printed...