Cutting Starboard HDPE to shape - best tool for curved cuts?

[George_SD]

Hi all,
I'm working on building swing doors for the companionway out of StarBoard HDPE and wanted to know what is the best tool for making curved cuts and leaving cleanest possible edges? I can make nice straight cuts, but wanted to see what works best for making clean curved cuts.

Any suggestions are appreciated.

[Scubaseas]

Router bit that is upthrust works well or spiral trim bit seems to be the cleanest cuts I've gotten. A jigsaw on slow speed is OK if you "burnish" the cut face with a hot iron. I've used a cabinet scraper to good effect to clean up saw blade cut marks.

[ggray]

I used a bandsaw, and it left a real smooth cut.

Router probably is smoother though.

[OldManMirage]

I've also had good success using a jigsaw with the appropriate blade. I cut a little wide and then file or sand to the shape I'm looking for.

[Benz]

Cut a pattern from thin plywood, then use it to cut the starboard with a flush trim router.

[Tellie]

Old fashioned elbow grease and a bit of paper works wonders on edgy Starboard edges.

[AKA-None]

Originally Posted by Tellie

Old fashioned elbow grease and a bit of paper works wonders on edgy Starboard edges.

There are also tools specifically for this purpose


Lower left

[Cheechako]

Routing from a template is nicest but may be more trouble.
Saw blades only leave marks. I would carefully bandsaw outside the line then used a router bit to clean it. Or just smooth it on a belt sander if you are handy doing that type of thing. I use a 6 x 48 stationary belt sander for things like that. Depends on how "smooth" is smooth to you.
Jig saws often create an angled cut.

[BAD ORCA]

Originally Posted by Benz

Cut a pattern from thin plywood, then use it to cut the starboard with a flush trim router.

This^

We cut a lot of this material at work. The cleanest edge will be using a triple flute flush trim bit with a 1/4" shank. Cut the Starboard or HDPE with a jigsaw /bandsaw to within 1/8" of your final cut line. Attach a well made 3/8" or thicker hardwood or similar template on the final cut line, and use that as a guide for the bearing. You can follow up with a small roundover or 45deg bit to break the sharp edge, or use a de-burring knife for plastics.