Cutouts for Battery Monitor and Inverter Display

[Howler]

Arguably, not an electrics topic but related…

I plan to install a battery monitor requiring a 2” round cutout in the cabinetry, and an inverter display panel requiring a 5” rectangular cutout. Like many recent production boats, the cabinetry is made of compressed wood with glued on fake veneer. On real wood I’d use a hole saw for the round cutout and a jigsaw with drilled pilot holes for the rectangular one. Will this work with fake wood without destroying the adjust areas? Suggestions welcome.

[rslifkin]

It should work fine as long as you drill carefully. For things with veneer (or gelcoated fiberglass) I generally tape over the area with painter's tape and drill through the tape. Also run the drill backwards for a few seconds to wear through the surface layer before you go forward and let the bit cut in. Both of those reduce the risk of chipping around the hole.

[Howler]

Originally Posted by rslifkin

It should work fine as long as you drill carefully. For things with veneer (or gelcoated fiberglass) I generally tape over the area with painter's tape and drill through the tape. Also run the drill backwards for a few seconds to wear through the surface layer before you go forward and let the bit cut in. Both of those reduce the risk of chipping around the hole.

Good suggestions... will do. Thanks!

[Allied39]

The holesaw should be fine, go easy. I would use a reverse blade for the jigsaw....one that cuts on the in stroke. Veneer will be fine if you do that.

[Kelkara]

Don't forget that the backside of the panel can also be damaged ... probably just minor cosmetic chipping with the jigsaw, but a holesaw can rip out big chunks if you're pushing hard. If you have access to the back of the panel once the pilot bit comes through, finish the hole from the other side ... otherwise go really gently as you break through.

[Howler]

Originally Posted by Allied39

The holesaw should be fine, go easy. I would use a reverse blade for the jigsaw....one that cuts on the in stroke. Veneer will be fine if you do that.

To be clear, are you suggesting cutting from the outside (decorative) surface of the panel with a reverse blade? I would have thought that that would tend to tear away the veneer laminate near the cut.

[SailingHarmonie]

Originally Posted by Howler

To be clear, are you suggesting cutting from the outside (decorative) surface of the panel with a reverse blade? I would have thought that that would tend to tear away the veneer laminate near the cut.

A "normal" jigsaw blade cuts on the up stroke (helps hold the saw down). A "reverse blade" cuts on the DOWN stroke which reduces chipping and tearout of the side the saw is resting on.

[wyb2]

2nd the reverse blade. Alternatively you can use a blade that’s really intended for metal, with the tiny hack-saw-size teeth. Turn the oscillation down to 0 if it’s adjustable on your saw and go slow. It’s slow and inefficient but you are less likely to snag and tear the veneer.

Another method is if you have any kind of rotary tool, score the veneer along the cut line, then follow the score line with the jigsaw. Bias toward the material being removed, so if it grabs the veneer it will only damage the throwaway piece.

[Howler]

Originally Posted by SailingHarmonie

A "normal" jigsaw blade cuts on the up stroke (helps hold the saw down). A "reverse blade" cuts on the DOWN stroke which reduces chipping and tearout of the side the saw is resting on.

Got it (had it backwards).

And I also liked Wyb2's suggestion for scoring the cut lines with a rotating tool before sawing.

Thanks!

[smac999]

Tape the area. .

Run the hole saw backwards to start the big hole

[kayakerChuck]

I've been using my oscillating tool for square/rectangular cut outs. It's not the fastest, but it's very easy and doesn't tear up anything. Drill the corners first- gently.

Carbide blades are expensive, but are worth the price.

[Madehn]

Once you are done with the holes apply a good coat of thinned epoxy to all of the compressed wood edges. This will help to hold together and to seal. Cut holes slightly smaller than needed the smooth out with drum sander on a dremmel tool. If there are screws to mount the rectangular instrument at the corners, I normally drill all the way through and thru bolt with a washer on the inside. Keeps from tearing out the mounting screws

[Howler]

I know I came to the right place. The suggestions are awesome. Thank you all. Always amazed at the wealth of knowledge this forum holds.