Kapton Tape
Kapton Tape, also known as Polyimide Tape, is an electrically insulating heat resistant tape that has many uses for Reprap:
- Insulation/fastening
Kapton tape is well suited for fastening heating elements. As such, it's the material of choice for fastening heating wire to the heater barrel of an extruder such as the Mendel extruder. For example, the Casainho extruder uses Kapton tape. Kapton can also be used to tape the temperature sensor to the printhead/extruder. - Print surface
Kapton tape is a usable print surface for printing ABS on a Heated Bed, though PEI has recently been found to be considerably easier to apply and keep clean. For ABS to stick to Kapton the Kapton needs to be hot (different sources mention minimum temperatures between 80-130 °C). Also the Kapton should be free of grease, grease can be removed with acetone or a propane torch. However, test your Kapton for fire resistance first! - Anti-friction
Peter is doing some research at using Kapton as a low-friction film, as an alternative to lubrication. See his blog post and about page.
Safety Risk
Polyimide has excellent heat resisting properties, however it has limits. In the event of excess temperature, even in very small areas such as caused by electrical sparks, the tape can burn fast enough to resemble a small explosion. Make sure everything is well insulated and secured!
Test your tape for fire resistance before using it. Testing can be done in an oven or with a soldering iron. I know mine won't burn (North90ty).
Fake Kapton
Real Kapton is expensive, and fake Kapton tape is offered on Ebay for less money. This fake tape might work well; I have a roll of tape labelled "Kapter" which works fine. However, test the heat resistance of your tape before using it!
The 6mm fake Kapton I purchased from Ebay I tried on a 45 watt soldering iron at full heat and the tape never smoked or melted but it did show some signs of stretching when I pulled it taut over the soldering iron tip. - Dark Alchemist
Vendors
These vendors are known to provide tape suitable for Reprap projects. Some of them sell it under the technical name, Polyimide Tape or Polyimide Sheet.
DealExtreme
People have claimed DealExtreme provides fake Kapton, or to not have received their product. This was taken from a previous edit, it's worth a second look per satisfied customers below.
That said, I have Deal-Extreme-Kapton and it withstands a soldering iron.
--Traumflug 10:32, 30 September 2011 (UTC)
Second that. I have nothing but good experience with the (4-5 rolls, different widths) "kapton" I've bought from dealextreme.
--Nudel 01:03, 1 October 2011 (UTC)
I bought a 200mm roll from DX. It's labled as "Koptan". It withstanda my 450°C soldering iron and the open flame from a lighter. Howerver the glue burns when lit with a lighter but didn't burn at 450°C.
--jCollasius 22:40, 1 Mai 2015 (UTC)
Dupont
Dupont makes several types of Kapton tape. The standard Kapton HN works up to 400 °C and has a coefficient of thermal conductivity of 0.12 W/mK.