Heated Kapton is Beautiful
Update 2010-04-18: Bre posted the video from the great night of kapton sanding.
I’ve been testing the new MakerBot Heated Build Platform and discovered something that make me very happy. Sanding the Kapton film with 220 grit sand paper makes printed objects stick perfectly. See the video below.
After an initial bit of frustration with the heated build platform I sanded the surface with 220 grit sand paper, increasing the surface area significantly, thus increasing the adhesive force. Since doing this I’ve had fewer failed prints, most of which were due to the Kapton being too cool.
Take a look a the difference in Kapton surface texture in the image below. The left side is unsanded. The right, sanded.

I’ve only tried the 220 grit paper, so I encourage everyone to test different coarsenesses and comment on your results. As I develop the conveyor belt build platform I will surely use the sanding method. The heated build platform is worth every penny.
Its interesting that you say that sanding kapton aided grip… Nophead reported the exact opposite here: http://hydraraptor.blogspot.com/2010/03/heated-bed-mk3.html
Perhaps the issue was that he used fine emery paper instead of the much coarser sandpaper you used?
Worth investingating, perhaps.
Ru
2010.04.13 at 07:59
[...] Charles wrote it up on his blog: After an initial bit of frustration with the heated build platform I sanded the surface with 220 grit sand paper, increasing the surface area significantly, thus increasing the adhesive force. Since doing this I’ve had fewer failed prints, most of which were due to the Kapton being too cool. [...]
Sanding the Heated Build Platform - MakerBot Industries
2010.04.17 at 08:33