Portlight cutout enlargement

[Christian Williams]

The cutout for my (removed) Bomar opening portlights is 7 x 13. That doesn't exactly match any replacement portlight I can find.

The Lewmar Size 0 cutout is quite a bit too small at 6 1/8 x 11 15/16ths..

The Lewmar Size 1 cutout is 6 3/4 x 13 5/8, so unless someone has a better idea Size 1 it is.

Now--how best to enlarge an existing cutout by only a little? Grind it? rasp it? Sabre saw?

Cheers,
Christian

 

[Matey]

Christian,

I cut mine out with a jig saw (carefully) after masking & marking well. Came out great

Good luck, Greg

 

[Loren Beach]

Perhaps that narrow cut -the straighter parts - might be done with a Fein Multimaster, and have your shop-vac hose intake held right up by the blade. Easy to control the material removal with one of those tools. The cheapie knock-offs work OK (and I do have one and have done some cuts in frp with it) but having watched a friend working with the real Fein, it's just an awesome power tool.

If you're on a budget, a good quality jig-saw should do fine. Just tape some heavy card stock over the outside surface to keep the base from "writing" on the gel coat surface.

Good Luck!



Loren

 

[mherrcat]

Make a template out of 1/4" plywood the size of the opening you need. You can trace that from the inner flange of the new portlight, but make the cutout slightly larger (1/16" all around) to allow for expansion/contraction, flexing etc. Clamp the template in place and use a small "palm" router and a 1" bit with a top mounted pilot bearing to cut the hole to match the template. You will have to cut part of the opening, move some clamps, cut some more, move some clamps, etc. until you have cut the complete opening. (Always leave a couple of clamps holding the template in place as you move others.) This will give you the cleanest cutout and the best fit.

 

[bigd14]

+2 for Jigsaw. If you are nervous about it, use a fresh jigsaw blade held with a pair of locking pliers and replace often. Might take awhile but you wont overshoot much... I too have had trouble cutting a nice radius with the Multimaster but that would be my third option.

 

[dwigle]

I cut mine with a sabre/jig saw and it worked well. If you do go with the saw, mask far enough around the new opening to keep the base of the saw from marring the gel coat.

Don Wigle
Wiggle Room
E 38 #8
Pt. Richmond, CA