While working on my 3D printer I noticed that a significant amount of heat was radiated out the bottom of the heated bed, a quick search confirmed that this was something noticed by many others. In the various discussions online I found that it was fairly common for people to insulate their heated beds in an effort to improve heating times and reduce energy consumption.
There are several options that others have already used, one common way is to use foam building insulation board and another to use building thermal/vapour barrier sheet.
I visited the local hardware store and found what I was after but unfortunately only in large sizes, the foam sheets were only sold in full sheets (think full sheet of plywood or MDF…) and thermal/vapour barrier start at around 1m wide and tens of metres long in even the smallest rolls, well overkill for the very small amount I needed!
In the same area of the hardware store I found an alternative, the tape that is typically used to join and seal the edges of the thermal/vapour barrier. These tapes are made of similar material to the barrier it is designed for, and while not as thick and insulative it was quite a bit cheaper so I thought I would give it a try.
I applied two criss-crossed layers, making sure to trim around the power terminals to prevent potential shorts. As an added bonus it turns out the 72mm wide roll is the perfect size for the heated bed on the CR-10 Mini, 4 strips wide and 3 deep perfectly cover the heated portion of the bed!
While I didn’t measure heating times before and after applying the tape I have noticed an improvement in heating performance, along with a very noticeable reduction in radiated heat from the bottom of the bed. Prior to applying the tape the bearing carrier plate would get quite warm from the radiated heat, after applying the tape it barely goes above ambient temperature. For the small outlay and time spent I think a very worthwhile upgrade to any 3D printer.