Feasibility of ahering common MK2 PCB Heater to Aluminum Build Plate...

I'm going to make some upgrades to my TAZ clone, and I would like to use a piece of 1/4" Mic-6 aluminum as a build plate. I have a 12" x 12" MK2-type PCB heater that I have been using under glass/PEI and it has been working just fine for me. My plan is to adhere it to the underside of the 1/4" plate using some 3M 468MP adhesive sheet and I may try to get fancy by using a vacuum bag for clamping pressure.

What I wonder is whether anyone has experience using a PCB heater in this fashion, and whether or not this is a good idea. I welcome all suggestions, comments, and (especially) skeptical criticism.

Part 2: Where/how would you mount the thermistor? Right now it is simply taped to the bottom of the PCB with kapton tape and that seems to work fine. I had thought about milling a grove in the bottom of the 1/4" Mic-6 plate, to accommodate the thermistor and its leads, but I suspect that milling said grove may lead to warping of the plate when heated.

I think you will find a PCB heater underpowered in that situation. The extra thermal mass of the build plate will add substantially to the heating time, unless you increase the heating power. I suggest a silicone heater instead.

You can buy silicone heaters with built in thermistors, although these thermistors tend to over-read because they are embedded in the silicone near the heater wires, instead of being in contact with the aluminium plate. A more accurate method would be to attach a thermistor directly to the build plate, for example drill a small hole in the edge of the plate and epoxy a bead thermistor in it.

This company [www.aliexpress.com] has a range of standard sizes and will make a heater to your own size, voltage and power specifications if you want.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I would imagine that I could research it and do some math, but do you think the heat-up time for 6.35mm aluminum would really be that much greater than my current 4mm borosilicate glass + 1.2mm PEI sheet?

It's all about the power. What is the power rating of the heater?

I have a 450W heater on my 317 x 305 x 6.35 mm aluminum bed and it heats to 105C in about 5 minutes. That's a power density of about 0.5 W/cm^2. If your heater delivers less power density than that, you can expect it to take longer to heat up and it may not reach 105C at all.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Thank you, the_digital_dentist, for chiming in. Your posts and developments have provided much of the inspiration for this next round of upgrades. The heater draws about 24.5A at 12.8V, so it's just over 300W and .33W/cm^2. I'm tempted to try it just because I have the heater on hand and it is easily undone if it doesn't prove adequate. While I have your ear, have you posted any pictures of your synchronous belt-drive z-axis setup? It makes perfect sense, and is something I hope to implement.

Details of my printer's Z axis are here: [www.instructables.com]

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]