shentheory wrote:So it just came in the mail yesterday - pulled off the glass and cleaned it, put the heat spreader on the HBP and clamped the it down with the glass on top. To my utter surprise it's actually taking MORE time to heat up.....
With a goal of 100c, it's taken about 10min to go from 80c to 85c. I live in Atlanta and it's so currently the ambient temp is not an issue at all. It get's up to 60 in about the same time as without one, but once it has to climb high for like ABS temps, it's significantly slower. I feel like i'm taking crazy pills

am i missing something? seems like taking it off would almost be better. any help/tips/advice would be appreciated.
yes, it will heat up slower, but like others already mentioned, the entire print surface will be more even which helps print adhesion.
It would be a good idea to do a PID auto tune for the heated bed now that you have heat spreader, that might help heat up a bit. At the very least PID tune will keep temp more stable.
My experience has been the heat spreader makes my machines heat up a bit quicker, although one machine is running at 13.8 volts and the other is 24 volt, that may be why?
The heat spreader has a plastic film on one side, make sure that side is down against hpb.
If your machine has a "meanwell" type psu instead of a ATX psu I would turn up the trim pot to up the voltage from 12 volts, you can probably get around 13.4 volts. Even the small increase in voltage will help reduce heat up time.
Measure the voltage before and after you adjust it, just for reference.
Note: If you do increase voltage you should PID tune the hot end also.
A towel does help, or a large glass lid from a cooking pot works good.
~*Brian V.
RostockMAX v2 (Stock)
MAX METAL "ShortyMAX"
MAX METAL Rostock MAX Printer Frame
NEMESIS Air Delta v1 & v2 -Aluminum delta printers
Rostock MAX "KITT" - Tri-Force Frame
GRABER i3 "Slim"