Measure Twice, Cut Once (Or don't cut at all???)

RinkerRookie · August 2017

I failed to take accurate measurements (let the jokes start flying now!) and got trigger happy ordering some new speakers on eBay for my '10 Captiva 246 BR. The existing opening is 5". The new speakers require a 5-5/8" opening. My first thought was to order a hole saw and cut a larger opening. Needless to say I'm very worried about the blade slipping and doing damage to the boat. I'm talking to the vendor about exchanging them for something that will fit, but I'm concerned they'll only have "junk" speakers as most everything I see is 6.5", requiring a hole larger than 5". Anyone attempt a similar project?

Black_Diamond · August 2017

Few ways to do this. Rotozip is a good one. You can make a blank to fill the center. Or scribe the diameter and go slow. Messy but very doable without disaster.

Willhound · August 2017

Very difficult to use a hole saw in an existing hole as there is nothing to guide the pilot bit. Might be possible to use a plywood jig, but difficult. Best thing is a Dremel type tool and a steady hand. Practice on some plywood first. When using a rotary cutting tool like a Dremel, work against the rotation, it's easier to control.
Or.....switch the speakers and don't cut anything....easiest in my opinion.

Liberty44140 · August 2017

I just went through this. I ordered the replacement speakers for my current and the new versions were 5/8" wider. I used a reciprocating saw. The glass is thick so it really is not possible for it to run away from you. Really is easy, the speakers should have came with a pattern. Masking tape around he area and draw your new hole pattern on the tape and then cut. The tape will keep the cut clean. Reccomend having a buddy hold a shop vac close as you'll make lots of dust. The speaker will cover any small imperfections that may arise.

Willhound · August 2017

Liberty44140 said:

I used a reciprocating saw.

@Liberty44140 a reciprocating saw?! Or do you mean a jig saw? A recip saw is like a sawzall. Pretty big for a job like that. Jig saw I'd say yeah, no problem.

Liberty44140 · August 2017

I used a reciprocating saw (cue tim the tool man Taylor) worked great, would have been tough to get the big base of a jig all the way around on a couple of my speaker holes.

Cableguy Greg · August 2017

I used a jig saw to cut in my new sub. I drilled holes big enough for the blade to go into. I also covered where I was cutting with blue painters tape to help with chipping. A new sharp fine cut blade is a must. I didn't want to go the rotozip route because it has run away from me when cutting holes in drywall.

nhsd · August 2017

If it were me (and since I already own a small router) I would make a plywood template and rout the hole. I suspect that you could do the same using a rotozip or a dremel with a pattern cutter installed. The template should help ensure a clean properly sized cut and minimize the opportunity to do any significant "whoops".....

On the other hand, there are a number of nice 5.25" speakers out there that would probably fit that hole (most need a minimum of 4.8") or a Rockford Fosgate T1S652 6.5" that needs a 5.02" hole might be a possibility, among others...

Wildboating · August 2017

As mentioned before,a pneumatic saw, jig saw or reciprocating saw makes easy work if it. Rotary tools are easy to get away. Stay away unless this is all you have. Take the time and cut the larger holes. 6.5" are standard and your best bet for quality at an affordable price.