What's the exact perfect cutout dia. for the Tempest mounting hole? (1 Viewer)

[jeff lam]

I made a trial cutout yesterday with the jasper 200. I measured 13+15/16in from the edges of the surround. I know Pat said it was less than the specified 14" but I don't remember exactly the size. So, I used the 13+15/16 hole on the jasper and it came out too big as well. Anyone made this cut recently? What is the exact size with the jasper so the tempest is snug but still flush all the way down in the baffle?

Thanks!

 

[Patrick Sun]

13 7/8"?

You could always get a tape measure, and measure the circumference of the Tempest basket, and divide by 3.14159 to get the diameter.

 

[Mike Strassburg]

Just cut mine over the weekend to 13 15/16" and the fit was fine. That's what the Adire WhitePapers suggested....

 

[Brian Bunge]

Jeff,

What do you consider "too big"? It's normal to have a little play when you drop the driver in.

Brian

 

[jeff lam]

Mike,

Did you use the Jasper 200 and 1/4" bit?

I use the Dewalt 621, jasper 200 and 1/4" MCLS spiral upcut bit. I set the jasper to 13 15/16" and it was way big, maybe even 2-3 stepps larger than the basket. I figure it may be 13 3/4" with my jasper 200.

 

[Mike Strassburg]

Jeff,

I'm a "low budget" operation so I borrowed a Bosch plunge router from a co-worker and used the "Mike's piece of pegboard" circle cutter with a 1/4" bit. Worked perfect!

Does your cut-out extend into the lip of the driver where the mounting holes are?? If not it shouldn't be an issue. My openings measure 13 15/16" and the subs drop right in perfectly.

Now routing away another 5/8" for flush-mounting is another issue......

 

[ThomasW]

Mike S.

Here's the technique for flush mounting with a router jig.

First cut the rebase with a 3/4" bit to fit the width and depth you want. Then make the cutout for the driver.

 

[Brian Bunge]

Thomas,

I just follow the Jasper instructions and use a 1 1/4" bit and move the pivot pin down 1" smaller to account for the larger bit.

Brian

P.S. Did you get my email?

 

[jeff lam]

Don't tell me with all the tempest projects going on here and all the jaspers out there nobody can tell me the exact measurement to use. Trust me, it's NOT 13-15/16".

 

[Patrick Sun]

Jeff, a few post up above, I gave you a way to determine what the diameter of the cutout for the Tempest should be. Go get some dental floss, and wrap it around the tempest were it'll recess into the hole. Take the length of the dental floss, and divide it by pi (3.14159). That's the diameter of the cutout for need for the driver.

 

[ThomasW]

I just follow the Jasper instructions and use a 1 1/4" bit and move the pivot pin down 1" smaller to account for the larger bit.

Brian
Yup I know, that that's the way they make the process foolproof
A similar correction can be done with the 3/4" bit and a little brain power.
Check the price the difference between 1-1/4" and a 3/4" carbide router bits. IMO using the 1-1/4" bit just burns up the router (it's a significantly higher work load) and makes tons of unnecessary saw dust.

 

[Jeffrey_S]

In the Adire Tempest Vented Application Note, it specifies a cutout of 13 7/8".

 

[Brian Bunge]

Thomas,

Yup I know, that that's the way they make the process foolproof

Well, accept when you forget to move the pivot pin down 1"! So with the 3/4" bit you'd subtract 1/2" from your actual rebate dimension?

Brian

 

[Mike Strassburg]

ThomasW,

Thanks for the tip, but it's too late for that as I already have a 13 15/16" opening in my endcap and it's already glued/screwed into the tube.

I did find a 9/16" rabbeting bit today online, so I'll end up having to sand away the last 1/16" as I need to remove 5/8" for the flushmount. Oh the joys of speaker building.....or why do you ALWAYS think of the right way to do it after it's already done!!!

I'm seriously considering building another one just so I can use all the little "lessons learned" and complete an entire sub in about 8 hours of work.

Over-all I'm having a blast building this thing and probably have about 20 hours into it, including 2-3 hours messing around designing my own speaker grills. Came out pretty nice I must say...

 

[Brian Bunge]

Mike,

You may find that it fits just fine only using the 9/16" bit. I've cut an 11" hole for a 12" driver before which didn't fit. The specs called for an 11 1/8" hole. So when I recut the hole the driver fit fine but then had a little play in it. So before you go trying to sand off that last 1/16", test fit your driver and see if it'll fit!

Brian