[mlundy57]

Hi all,

I've been lurking for a couple of weeks soaking up as much advice as I can both from this board and emails with Danny. I am getting ready to attempt my first ever speaker cabinet build and have a question. I am going to start with a pair of N1X speakers now then move up to an N3/N3S combo this fall.

First question (of many to come I'm sure): What do you use to cut out the driver and port openings? The tweeter opening has a 5.11" diameter counter sink with a 4.3" diameter through hole and the rear port has a 3.98" diameter through hole. I was planning on using my Jasper circle jig to route out these openings. The problem is the jig is calibrated in 1/16th" increments. The closest my jig will get to these measurements is: for 3.98" - 4.000"; for 4.3" - 4.3125' ( 4-5/16"); and for 5.11" - 5.125" (5-1/8").

Is there some other type of circle jig that will allow me to cut the openings as specified in the plans?

Thanks

[mlundy57]

Another question is on material. It seems like most of you build the cabinets out of 3/4" MDF but some others use Baltic Birch. What type of differences will there be in the cabinet's performance between the two materials?

Is the Baltic Birch plywood you use the same as cabinet grade hardwood veneered plywood (birch, red oak, cherry, maple)?

Thanks

[mlundy57]

When installing magnets to hold on the grill:

(1) Do you install them before the veneer is applied or after?

(2) Do you countersink them then add wood filler on top and sand flush to the baffle face before painting or veneering?

(3) what type/size/shape magnets work best?

Thanks

[Danny Richie]

Welcome to Audio Circle.

I am playing catch up now that I am back from Lone Star Audio fest. I will get back to this ASAP.

Thanks,

[jparkhur]

Another question is on material. It seems like most of you build the cabinets out of 3/4" MDF but some others use Baltic Birch. What type of differences will there be in the cabinet's performance between the two materials?

Is the Baltic Birch plywood you use the same as cabinet grade hardwood veneered plywood (birch, red oak, cherry, maple)?

Thanks

Baltic vs MDF is a preference.  I like baltic because I can get it in good quality and i like the grain look.  I do mdf also, but only so many people like the smell of mdf in the morning!  I don't veneer well either.  Pick your battle.

Put the magnets on the back side of the baffle.  I just did a pair for GD and i used a good quality pair of neo magnets and set them in the back side of the front baffle.  Then they wont mess with veneering.

JP

[jparkhur]

When installing magnets to hold on the grill:

(1) Do you install them before the veneer is applied or after?

(2) Do you countersink them then add wood filler on top and sand flush to the baffle face before painting or veneering?

I counter sink them and then wood fill  or glue around it.  Wont matter, never see it.  My magnets will stick together through my palm.  get good ones.







(3) what type/size/shape magnets work best?

Thanks

[jparkhur]

Hi all,

I've been lurking for a couple of weeks soaking up as much advice as I can both from this board and emails with Danny. I am getting ready to attempt my first ever speaker cabinet build and have a question. I am going to start with a pair of N1X speakers now then move up to an N3/N3S combo this fall.

First question (of many to come I'm sure): What do you use to cut out the driver and port openings? The tweeter opening has a 5.11" diameter counter sink with a 4.3" diameter through hole and the rear port has a 3.98" diameter through hole. I was planning on using my Jasper circle jig to route out these openings. The problem is the jig is calibrated in 1/16th" increments. The closest my jig will get to these measurements is: for 3.98" - 4.000"; for 4.3" - 4.3125' ( 4-5/16"); and for 5.11" - 5.125" (5-1/8").

Is there some other type of circle jig that will allow me to cut the openings as specified in the plans?

Thanks

I use that one too from Madisound, but a 1/32 of play is not bad.  It will only matter on the tweeter cap insert, not the woofer hole.  There is enough play with the woofer over hang you should be fine, the tweeter you may have to cut it small by a 1/32 or 1/16th and sand out some.. or make a wood guide some how.

JP

[WireNut]

 I use endmills alot rather then router bits because there are so many sizes available. I think the Jasper jig is calibrated for a 1/4" tool. You could use undersize or oversize endmills from places like J&L Industrial supply to compensate for the jasper jig. Maybe something like a 9/32 endmill or a 7/32 endmill. You'll need to calculate out the correct size endmill to purchase. Note: When ordering endmills make sure they’re available in the correct shank size to fit your routers collets, 1/4, 3/8, or 1/2 and also center cutting if needed for plunging.

 http://www.mscdirect.com/browse/Milling?navid=12106224


 

[NachoTime]

RE: the Jasper jig...

Since there is an alignment disc, it's conceivable you could skew the jig slightly one way or another to make the hole slightly bigger/smaller than the size indicated.  Naturally you'll want to experiment on some scrap wood before committing to the finished piece.

[NeilT]

http://www.parts-express.com/pe/showdetl.cfm?partnumber=365-270&utm_source=google&utm_medium=cpc&utm_campaign=pla

This circle jig works very well, you set it up for whatever size you need with calipers or tape.

Neil

[Outofthewoods]

Welcome aboard! 

Another trick that will work is to drill the peg hole using the correct size bit and go straight in. Set your depth on the router and cut the recess (outside diameter) using whatever peg hole will get you closest to your target, but go with the undersized dimension. Now, grab the drill again and hold it at a slight angle and go around the hole to bore it a hair. Keep the angle and pressure the same as you go around so that you don't create an oval. Now make another pass with your router. You should be able to judge how much (if at all) you'll need to open up the peg hole to make your recess the right diameter. You might want to try it on some scrap wood first.

You could also use this method to make a template that could be used over and over again. You'd need a top bearing flush trim bit when using a template to cut the recesses.

Hope that makes sense.

Be safe and have fun!

Ruben

[srb]

Now, grab the drill again and hold it at a slight angle and go around the hole to bore it a hair. Keep the angle and pressure the same as you go around so that you don't create an oval. Now make another pass with your router. You should be able to judge how much (if at all) you'll need to open up the peg hole to make your recess the right diameter.

I'm obviously missing something here.  Why wouldn't you just enlarge the peg hole with a larger bit to avoid any possibility of creating a less than perfectly round hole?

Steve

[lacro]

There has been are a lot of great ideas already presented by those with a lot more knowledge than me, but what worked great for me was my homemade jig.
 Just made my own from masonite. The center pin is an 1/8" drill bit the jig swings around. I just measured the radius from the far edge of the router bit to the center of the pivot pin hole. with a caliper. I drilled the hole in the jig with a brad point drill to get an exact center. It works PERFECT!!
 One tweeter counter bore was just a few thousandths under size, so I opened the hole in the jig a tiny bit with a larger drill bit.
I just held the jig tightly against the pivot pin. The new slightly larger hole allowed the counterbore to increase a few thousandths.
 

[PDR]

Made my own as well.....worked slick.
I used the heck out of this on my round super v build.....never missed a beat

[WireNut]

I did the same as Lacro and PDR. Worked great for me. I suggested the over and undersize endmills since you already own a jig in 1/16" increments. The tool bit in the router pic is a .500 carbide 4 flute center cutting endmill. The center fixture pin is an 1/8" steel dowel.


 

[rockdrummer]

I made my own for an AV 1 build and am making my own for an xls and sealed sub build. Couple practice cuts on scrap and careful measurements i was on my way. Particularly fun for me because i am not a seasoned woodworker. Made the build go at a slow pace, which i wanted, and left me with some diy accomplishment!!

You will always get your questions answered here. And if you feel like they may be silly, i have probably already asked so dont hesitate!

Ben

[Outofthewoods]

I'm obviously missing something here.  Why wouldn't you just enlarge the peg hole with a larger bit to avoid any possibility of creating a less than perfectly round hole?

Steve

Nope, you're not missing a thing.

If you have the right size bit that works, too. I was suggesting a simple method that would work with the tools I know he has. It's really not hard to get it right by using the method I suggested. Bore it out 1/64" (1/32" increase in diameter) and you get a + 1/32"
increment on your Jasper. Don't quite need 1/32"? Bore it a little less. You could even stick a nail through the peg hole and roll it around to increase the diameter a bit. Just don't push the peg all the way through when you rout. Easy peasy!

Keep in mind that even if he were not absolutely "perfect" with his bore we're dealing with a small circle here, so it's not likely to be an issue.

Ruben

[mlundy57]

Thanks a lot for all the suggestions. I found the jig from Parts Express and ordered it. I like the idea of using end mills also. It seems that a 4 flute endmill would make a smoother cut than a 2 flute straight bit.

Thanks for the ideas on making my own jigs. I have hardboard laying around the garage and 2 routers, the larger size with a circular base (though it's currently in the router table) and a smaller trim router with the square base.

I have some MDF so I'll start a build with that. I also found a local source for Baltic Birch. They stock 3/4" 13 ply but can order larger. I've never veneered anything in my life so the idea of building with the birch is appealing. Not sure how to hide the magnets in the baffle of the birch plywood though.

Hopefully I can start cutting either tomorrow or Friday.

[Captainhemo]

Put the magnets in  from  the rear  before you  glue the baffles on.  Drill em just deep enoght so that you leave a real  thin layer of wood above them.  just be careful  when  pressing them in  that you  don't push  too  far and break through the baffle.  Us e good strong  magnets.
I used these on my last build,  they worked well.   
http://www.kjmagnetics.com/proddetail.asp?prod=D46-N52

-jay

[rockdrummer]

Before you glue the front baffle in place, you can inset them in the back of said baffle.  Just carefully drill in a small amount to seat the magnet.  If you use the good, strong magnets, they will hold through lots of wood.  I don't know exact measurements to advise you to use, but others might. 

Oops, what jay said....

ben