Evening out bed temperature?

My bed temp is horribly uneven. I know where I cannot have ABS parts on the bed, because anything there always peels. Has anyone tried putting a thick sheet of aluminum or copper between the heating element and the glass? I can only imagine it’d help spread the temperature difference out.


Yes, it works great, I highly reccommend it. There is no better adhesion modification you can do to your 3d printer if you are printing ABS, and I include building an enclosure in that list. According to my year long test and my thermal imaging camera, it works an insane amount better than stock. A 12" x 12" plate will be slightly too big for the stock bed corners on a Taz 5, here are clearanced ones: http://www.thingiverse.com/thing:1098784
You can also see the aluminum bed in there with a Buildtak sheet on it. PEI works well too.

The tricky part is finding a truly flat 3/16" thick metal sheet. Aluminum or copper work. I seem to be the only person who has attempted this that actually ended up with a truly flat plate direct from the plate maker. Ideally you would want a 3/16" thick 12" x 12" 7072 tool plate that has been machined to tolerance. Near as I can tell, such a plate doesn’t actually exist unless you have one custom made. A flat “mill finish” (just came off the rolling mill, rough) plate should work since you are adhering stuff to the top and bottom, but only if you get a flat one. they are easy to straighten I find, but some people find it to be a deal breaker.

You adhere a surface of some sort on top (i’ve never tried directly on the plate, that might also work), the bed heater to the bottom (Lulzbot or IT works https://itworks3d.com/product-category/parts/ have them in stock usually). If you go with an Aluminum plate, it’s also going to be slightly lighter than the stock glass plate which is an added bonus. A 1/4" thick toolplate sounds like a good alternative in theory, but they are much to heavy.

Are you saying you’re using aluminum INSTEAD of the PEI glass? Hard to understand it exactly. I’m talking about removing the heating element from the glass, attach it to the aluminum, then attach the glass to the other side. The aluminum would help distribute the heat more evenly across the glass.

The Aluminum replaces the Glass. Then you use PEI or Buildtak on top of it. The glass only acts as a heat distribution and support matrix. By removing it and replacing it with an aluminum plate you improve the heat transfer dramatically and decrease bed mass while retaining the same amount of support.