How to cut rectangular holes for speakers?

[vidmouse]

I'm leaning towards mounting my speakers through the panel, leaving their natural pc-face exposed... any recommendations on how to cut rectangular holes cleanly?

[NiteWalker]

Make a template out of MDF or plywood and use a router and flush trim or pattern bit to trim it up.

[ChadTower]

If no router:  Use a drill to drill a hole just inside the line, then use whatever saw you have on hand to cut the square out.  Sand/square up with a chisel.  A jigsaw is great here but if you're only doing it once a keyhole saw is a very cheap alternative.

[Joystick Jerk]

Make a template out of MDF or plywood and use a router and flush trim or pattern bit to trim it up.

Definitely works, but kind of overkill. The drill/jigsaw method will do you up good.

[NiteWalker]

I'd say a tight fit is important because any gaps will let light seep through.

[vidmouse]

The funny thing(s) is/are  that I currently:

> Have a router but only a slot cutting bit for it
> Have no jigsaw

 

I actually have some more tools coming... went a little
crazy this week and ordered a hole saw set, forstner bit
set, and router bit set which should be coming.  Didn't
order a jigsaw but was strongly considering it.

I did think of another option vs the rectangular hole but
I think the sound might suck... thought about just drilling
holes in a pattern through the panel wood, let the speakers
cover up and blast through the holes.  Somehow I don't think
it would sound very good, but has anyone tried this?
(or cut slots in wood, similar concept)

[ChadTower]

I'd say a tight fit is important because any gaps will let light seep through.

You can bezel that, though, and we both know a jigsaw can cut a small rectangle accurately.

[ChicagoDave]

I just drilled a big hole and then used a jigsaw to cut the hole the size of the speakers.

Here are some pics of the speaker installation:

http://www.davestojak.com/cabinet.htm

[vidmouse]

Cool website; I like how it's organized.  It was very easy to see how you mounted those speakers but I don't think it will quite work for me... mine are way deeper than those.  My plan is to cut out the rectangular holes and use small L-brackets to hold them in place.

[ChicagoDave]

Cool website; I like how it's organized.  It was very easy to see how you mounted those speakers but I don't think it will quite work for me... mine are way deeper than those.  My plan is to cut out the rectangular holes and use small L-brackets to hold them in place.

Thanks, and good luck on your project!

[vidmouse]

Ok I tried cutting a rectangular hole using my router on a piece of scrap MDF last night, it worked and is close, but the hole didn't have nice clean edges -- ie I'm afraid a lot of light will shine through if I do this with the real panel.  Any quick tips on straight edges for the router-newbie?

[ChadTower]

You'll have to elaborate on what you mean by "didn't have clean edges"... they should be nearly perfect with a router.

[vidmouse]

Looking down on the hole, the edges of the rectangle have a few bump-outs where I either nudged something w/ the router as I was dragging it, or just had an unsteady hand as I was pulling it.  As this was scrap and I wanted to see how good I could make it just by following pre-drawn lines, I did not use a template per Nitewalker's note above... which I'm not quite sure I understand, seems like you'd have to cut a rectangular hole to make a template anyway.  Do you ever use some kind of straightedge guide when using your router in this way?

[ChadTower]

I'm still learning too but if I wanted a perfectly straight edge I would use a straight edge guide.  I wouldn't bother with a template for a rectangle unless I had to cut it a bunch of times.

Perhaps you were trying to cut off too much in one pass.

[NiteWalker]

As this was scrap and I wanted to see how good I could make it just by following pre-drawn lines,

The problem was that you used the router freehand. For most cuts the router needs to be guided somehow.

Since it's only for one set of speakers a good way is to use a jigsaw to cut close to the layout lines and sand for a tight fit. If you make it a bit too big, try some high density foam weather stripping to seal the gaps. Look at timoe's thread on building a joystick recess routing jig. It gives good instructions on how to do what you want to, just adjust the dimensions to your speakers.

[Chris G]

I've found that going the router-route (ha) works much better than sanding.  Just clamp down a guide and use a flush-trim bit.  Comes out nearly perfect every time I've tried it so far and I'm a novice.  I guess for something you won't see like a speaker cutout, maybe it's not important to have it perfectly straight, but even so it seems faster too using the router.

[NiteWalker]

That would be my first choice too.
Anything that lets me use the router.

[Joystick Jerk]

If you're worried about light getting through hairline gaps between the speaker and MDF, just get some wide electrical tape or duct tape and use to cover where the speaker and MDF meet on the inside of the cab.

[ChadTower]

Would tape stretched over a gap cause any vibration type issues?  I've seen things like that resonate with the sound, creating a buzz.  I bet he could easily get away with some type of foam rubber weatherstripping in that same space.

[Joystick Jerk]

It could resonote if the gap was quite wide, but I wouldn't forsee any problems if they are just hairline gaps of a few millimeters at most.

[javeryh]

This is pretty easy if you have the proper tools and assuming that a very slight curve in each corner is acceptable.

1.  Layout your rectangle on the workpiece
2.  Measure in from each side by 1/8" (or less depending on how good you are with measurements and stuff) and make another "interior rectangle." Now in each corner you should have a reference point that is 1/8" in from the sides
3.  Using a 1/4" drill bit, drill out the 4 corners using the interior rectangle points as the center of the drill bit.  It helps to use a nail or screw to make an indentation on the point dso the bit does not slip.
4.  Using a jigsaw, freehand the rest of the rectangle staying about 1/8"-1/4" from the line which will remove the bulk of the material.
5.  Using a straight edge, some clamps (to hold the straightedge in place) and your router with a pattern making bit, remove the excess material exactly on the line (you have to do this for each side)
6.  Use a chisel if you really want to square up the corners but you probably don't have to.

I detail how to do this with pics HERE - I just cut out my coin door (so my rounded corners were a little severe) but the process is exactly the same.  Also check out HERE for detailed pictures of setting up the router and straight edge - actually, in this post I cut out a perfect rectangle.  Hope this helps.

[unclet]

I had hairline gaps around my marquee.  I went to a hobby store and pickup some cheap black felt (you know what felt is .... right?)    Then I simply stapled the felt around the gaps which stopped the light from seeping through.

[miles2912]

When using a router you do not free-hand it.  Use a guide to make a straight line,  The problem is the corners.  You will need a chisel (yuck) or a jig saw to finish it.  javeryh's post has a link to an example.  Good stuff.

Don

[Crowquill]

To block light, I used some black craft foam from Wal-mart. Sheets that even have an adhesive backing were less than a dollar. I cut out the foam and left it to extend over the edge of the speaker. This served double-purpose as a spacer since I drilled the holes too small and the speaker's cone and surround couldn't vibrate properly (my speakers were "de-cased").