Insulation: Best way to cut and hole neoprene

[Stigma]

Hey all,

This might be a stupid question, but what method do you guys feel works best for:

- Making clean holes in neoprene sheets (for screws ect.)
- Shaping (ie. cutting) neoprene
- Making a clean large circular hole that can fit tighly around the EVAP head.

So far I have only used the most strightforward method of cutting with a exacto-knife or just plain scissors, and that works ok for straight cuts, but I'm having a hard time making a "perfect" circle for the EVAP head, and it would preferable if it was snug enough to make airproof with a little dielectric grease in the joins, and for that it needs to be better than what I can cut by hand in these thick sheets. Got any smart tricks to use?

And for the holes, my only two ideas are either to use a very thin drill and try to drill it carefully just as if it were wood, but I don't know if that will just shred it to pieces instead. Perhaps it better just to push a hole through with a nail or something instead? Again, any tips?

-Stigma

[n00b 0f l337]

Cup for circles.
Push it in hard, then cut within the line, that way you squish it over and stretch.

[Stigma]

Yea, I figure making the hole slightly smaller than the head actually is would be ideal, since the neoprene stretches a little bit, and then the natural tension of the material will in large part help keep it airtight (with a little grease at the seam).

-Stigma

[[XC] 2long4u]

Cookie cutter.

Seriously, they make a tool for cutting holes in leather for belts. Kinda like a hole punch for paper but with different sizes. Get one of those and you are good to go.

Here ya go. http://cgi.ebay.com/Quality-Leather-...QQcmdZViewItem

[bassie]

Cookie cutter.

Seriously, they make a tool for cutting holes in leather for belts. Kinda like a hole punch for paper but with different sizes. Get one of those and you are good to go.

Here ya go. http://cgi.ebay.com/Quality-Leather-...QQcmdZViewItem

Bit smal for a evap?

[tim-]

well I normally just use a knife and/or scissor for shaping, knife mostly for thicker insulation.

well to be honest it's not that important to make perfect holes, better do them little smaller and then push them over the evap or whatsoever, otherwise holesaw works.

[[XC] 2long4u]

Bit smal for a evap?

n00b already gave a suggestion for the evap. I was giving a suggestion for the retaining screw holes.