[Mark_Walsh]

So that is the question: how to make nice round holes in my subwoofer cabinet for:

a) the speaker (30cm) itself
b) the port (3" or 4" stormwater pipe)

Given that 33mm particle board costs the same as 18mm ply, I thought I would use the particle board.  Nice and heavy, perhaps fewer cabinet resonances, but possibly a bigger job to make the holes.

I have a power drill, bench saw and I have borrowed a jig-saw, but I am wondering if a router is the way to go, but have no idea really.  If it is, how do you get nice small holes for small ports or if I want to finish the port a la:

http://www.speakerbuilder.net/web_files/Articles/porttut/porttut.htm

All thoughts gratefully read and cogitated over!

Regards,
Mark

[mgalusha]

A router and a Jasper Jig is about the best way to go. http://www.jasperaudio.com/

You can make up a DIY circle jig for your router but for the price of the Jasper products it's hard to go wrong.

Parts Express has a sale going where you could get both the model 200 and model 400 for a combo price of $49.90, you have to ask for (or type in) part number 365-260.  This is $20 less than buying them seperately.

You might want to consider MDF instead of particle board. It's basically a higher density version of particle board and quite inexpensive. Around USD $22.00 for a full sheet of  3/4" (19mm)

[Mark_Walsh]

Thanks Mgalusha,

So would a normal hobbiest/DIY router cut through 33mm MDF or particle board, or would I need a chunkier tradesman's version to do that?  

For the thicker board, is it just a matter of cutting from both sides and having the holes meet up?

The Jasper website shows a speaker cutout with a nice rebate for the speaker to flush mount.  Which do you do first, the rebate for the flush mount, or the speaker hole?

Any ideas for the Australian purchasers.  Never purchased anything on internet before ... maybe time to start.

Regards,
Mark.

[rosconey]

take a look at ryobi-the bigger ones are very nice-
1/2 inch collet,varialbe speed, 2hp.
solid and well built for 100$-also made in america if you can believe that

[elektratig]

Mark,

When cutting holes with a Jasper Jig, I cut the rebate first, then the speaker cutout itself.  For the Jasper Jig (or any similar homemade jig), you need a 1/8" pivot hole drilled in the center of the circle-to-be.  If you cut the speaker cutout first, there's no center for the pivot hole.

Many seem to route halfway through on each side.  I don't.  I route from the outside all the way through.  Make sure that the panel you're routing -- including the cutout-to-be -- is firmly attached to your working surface.  Use double-sided carpet tape, or drill the center pivot hole all the way through the panel and into the working surface (no problem if that surface is a piece of cheap plywood), or both.  In that way, the cutout won't shift as you complete it.

I'm in the US and don't know what brands and models are readily available in Australia.  Certainly, you don't need a monster for this job -- any 1 3/4 to 2 1/4 HP router should be fine.  Make sure you get a model with a 1/2" collet.  Figure out what's available in your area and search some of the woodworking forums such as http://www.woodworking.com , to see which they like.  My experience is that all of the major brands have advocates.  (As with audio, no one agrees on anything.)  FWIW, I have a DeWalt and love it.

Last year, an Australian manufacturer, Triton, made a big splash in the US with a large (3 HP) but very flexible model.   You don't need 3 HP, but the company seems to be well respected and presumably has less powerful models.

On the Ryobi, check out http://www.bt3central.com for views.  Many have it and like it just fine.

One other thing: don't cheap out on the router bit.  That thing spins at 20K rpm and I take no chances.  See if Whiteside bits are available in Australia.  They are the absolute top end, and priced accordingly, but well worth it.  The other generally-recommended brand is MLCS.

Good luck!

Tempest Construction Pix (including my DeWalt w/ Jasper Jig): http://www.audiocircle.com/index.php?action=gallery;area=browse;album=130

[elektratig]

Mark,

When cutting holes with a Jasper Jig, I cut the rebate first, then the speaker cutout itself.  For the Jasper Jig (or any similar homemade jig), you need a 1/8" pivot hole drilled in the center of the circle-to-be.  If you cut the speaker cutout first, there's no center for the pivot hole.

Many seem to route halfway through on each side.  I don't.  I route from the outside all the way through.  Make sure that the panel you're routing -- including the cutout-to-be -- is firmly attached to your working surface.  Use double-sided carpet tape, or drill the center pivot hole all the way through the panel and into the working surface (no problem if that surface is a piece of cheap plywood), or both.  In that way, the cutout won't shift as you complete it.

I'm in the US and don't know what brands and models are readily available in Australia.  Certainly, you don't need a monster for this job -- any 1 3/4 to 2 1/4 HP router should be fine.  Make sure you get a model with a 1/2" collet.  Figure out what's available in your area and search some of the woodworking forums such as http://www.woodworking.com , to see which they like.  My experience is that all of the major brands have advocates.  (As with audio, no one agrees on anything.)  FWIW, I have a DeWalt and love it.

Last year, an Australian manufacturer, Triton, made a big splash in the US with a large (3 HP) but very flexible model.   You don't need 3 HP, but the company seems to be well respected and presumably has less powerful models.

On the Ryobi, check out http://www.bt3central.com for views.  Many have it and like it just fine.

One other thing: don't cheap out on the router bit.  That thing spins at 20K rpm and I take no chances.  See if Whiteside bits are available in Australia.  They are the absolute top end, and priced accordingly, but well worth it.  The other generally-recommended brand is MLCS.

Good luck!

Tempest Construction Pix (including my DeWalt w/ Jasper Jig): http://www.audiocircle.com/index.php?action=gallery;area=browse;album=130

[Mark_Walsh]

Thanks for the information, Fellas.

I had toyed with the idea of using a good laminate trimmer, given that this is not going to be occupation, but I noticed that they spin at 30000 rpm, and that is with their little 1/4" bit.  With a larger diameter and much heavier router bit (such as say a 3/8" radius bit for rounding out vent ports) that might be a little bit unfair on the trimmer (more inertia, etc.)

Has anyone successfully used a laminate trimmer as a little router with the heavier bits?


Regarding Triton:

The  Triton gear is MOST excellent.  They have engineered them specifically with fine tolerances so that they can be used for precision work.  Originally they made saw tables that you could use your home circular saw, but the results were affected by the end-float and other slop in the bearings.  Then they made their own circular saw for that task, and have expanded over 25 years or more into some really top end woodworking gear, both electrical and "accessories" such as router tables, etc.  Their electrical stuff costs an arm and a leg over here though (and that is even if you use them safely ... )

Many thanks,
Mark Walsh.

[bubba966]

Mark,

If you use a 1/4" spiral upcut bit, and don't try to do the entire depth in one pass (maybe make three or 4 passes, increasing the depth each pass), a laminate trimmer will work.

Also, let the bit do the work, don't try to push it beyond what it can remove. Meaning don't move too fast. But don't move so slow that you burn the workpiece (and the bit). That's the not so easy part of routing, getting the speed of the cut just right.

Another thing, don't go for a plunge router if you don't go the trimmer route. Plunge routers aren't as accurate as a standard router.

[bubba966]

Oh, don't know if you've got Porter Cable routers available in your area. But the PC model 690 is the router that Pro's use. And out of all the various routers I've used (DeWalt, Ryobi, Bosch, and a few others I don't even remember 'cause there was no reason to) I'll have to agree there's nothing better than a 690...