Reddit reviews 300 X 300mm (Approx. 12" X 12") 120V 750W, KEENOVO Universal Flexible Silicone Heater Mat/Pad, 3D Printer Heated Bed Heating Element

Keenovo makes good stuff. It isn't 24v it's 120v. You can use a relay to power it from the mains. If you go this route you could get by with a smaller psu.

300 X 300mm (approx. 12" X 12") 120V 750W, KEENOVO Universal Flexible Silicone Heater Mat/Pad, 3D Printer Heated Bed Heating Element https://www.amazon.com/dp/B00V81ZI70/ref=cm_sw_r_cp_apa_i_zO0PDb0BGQFH9

Yes, all 40x40 mm extrusion.


X and Y axis use 24x8mm linear guides, and 400 step/rev motors all bolted to 1/4" MIC6 tooling plate.


Z axis has an OnDrives Rino 30:1 worm gear reducer driven by a NEMA-23 motor to prevent bed-drop on power off. It works perfectly. There are two 760 mm long x 15 x15 mm linear guides.


Bed is 300x300x8mm MIC6 tooling plate with a PEI print surface and a 750W line powered heater on a 3 point leveling system that allows the bed to expand when heated without creating lateral stress on the leveling screws. Belts are 10mm wide, steel core, HTD-3M. Belt stretch plus drive shaft torsion has been measured at about 42 um/kg load.

The stock CR-10 will print some stock nylons (the "low" temperature ones) if you have it in an enclosure that will maintain a proper ambient temperature so you don't have drafts. It's important to realize that there is a learning curve to printing any filaments that aren't PLA. Depending on which nylon filament you choose (of which there are many, many, many to choose from), you may benefit from an upgraded hotend and maybe an upgrade to your bed heater. At the moment, I have an e3d v6 hotend with a Volcano heater block installed, plus this Keenovo silicone heater for my print bed.

The v6/Volcano is pretty much a necessary upgrade if you're printing nylons that require above 240C. The stock hotend will melt the PTFE tubing that feeds the filament if you use the stock hotend above that temperature. The heater upgrade is half convenience and half necessity. The stock bed heater takes about 40 minutes to get up to temperature for nylon/PC/etc, whereas the Keenovo one only take about 6 minutes. In my case, I'm always time starved so it was worth the upgrade.

Which nylon did you end up ordering?

What bed are you using? If its aluminum, you may want to go 110v rather than 12/24v because its got much higher thermal mass and takes a good bit more energy to heat up. If you're going PEI on top, its also a thermal insulator, so you need a bit more oomph to get it heated up quickly.

I'm using this one: https://www.amazon.com/approx-KEENOVO-Universal-Flexible-Silicone/dp/B00V81ZI70

It heats up the bed very quickly, maintains temperature very evenly, and is extremely well made. You just need to get a DC/AC SSR to control it. The Duet will report a warning that its overpowered when you run the heater calibration on it, but its overpowered in a good way. I installed a second dedicated power switch and plug on the printer for the 110v circuit, so I can power the Duet with the bed shut off or unplugged (which is safer for screwing around with the printer).

Make sure you run a line from the ground pin on your 110v feed to the aluminum frame on the printer, so if you ever get a short, it'll run power to ground and trip a GFCI outlet/breaker rather than making you dead when you touch it.

It took maybe three weeks to get, even from Amazon, but I think it was worth the wait.

Edit: if you go that route, I uploaded to Thingiverse a protective cap for the particular solid state relay I used that better protects the 110v circuit from accidental contact: https://www.thingiverse.com/thing:2497356

Guessing a silicone heating mat like this