I've got a consumer-grade, 18 gauge pneumatic brad nailer that just blew a gasket. It's a discontinued model with no repair parts available.
The gasket I'm referring to, labelled as part 9 on the left side of the diagram below, goes between the head cap (part 8) and the housing for the piston (part 30).
For scale, it's about 2.25" x 2.5", a little over 1 mm thick, and about 1/8" wide (the thickness of the housing wall). It feels like it might be polypropylene. The gasket tore apart in use, allowing air to leak out too fast for the gun to be useful.
A replacement gasket needs to have a few characteristics:
- The thickness needs to be very close to the original to provide proper clearances for the components inside.
- The housing wall is only 1/8" thick, the shape is skinny and complex, and there's not much surface area. The gasket shape needs to be precise to accurately mate with the whole contact surface. The material must be soft enough to compress and seal surface irregularities, but rigid enough to not flex out of the gap under pressure.
- It must handle 100 psi without ballooning out or tearing.
Is there a common sheet or caulk-like gasket material that would be suitable for making a replacement?
As supplementary insight, if any reader has attempted a similar repair, based on that experience, is a gasket of this type, tolerances, and complexity even practical to reproduce at home?