Suggest a sub/plan

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After a brief review of Art's sketches can I ask some rookie/noob question as the the sequence of the build? Basically a 2 sheet build, right?

I assume there is some forgiveness in actual construction. Some measurements are to a ten-thousandths of an inch... Leaning on PL glue and shooting 16g nails with the occasional clamp for help lining things up. How far am I off? Thanks!
You can get 2 Keystone cabinets out of three 4x8 sheets, but you will need 2 sheets for one.

I always do the corner routing before assembly to save router bits which tend to disintegrate when they hit screw heads ;).

With four horsepower behind the driver, I run a bead of paintable caulk around the joints to be sure there will be no whistling leaks.
As long as the cabinet has no air leaks, don't worry about anything much if you are within 1/8" inch of the plans.

Art
 
Thanks Art. I continue to glean from the Keystone thread and found the info relating to the braces.

Seems weird there's no info or FAQ for cabinet construction in the construction forum... Not opposed to just jumping in with my wooddorking experience, it just seems like there are some tricks to lining up the horn, etc. I think I might make a foam board full scale drawing to guide me and use a band clamp to hold things while I tweak and fasten.

"How powerful is that sub?" 4HP! :D
 
if you make a foam board scale model, you can just transfer that drawing onto a side one of the keystone. draw a dot in the middle of each panel on either end. put side 1 on top of side 2, drill holes straight through your dots. conect the dots on side 2. Now you have pilot holes, AND you have the drawing on both side. Dry fit it all together if your unsure of your skills, then let er rip with either arts yellow glue or PL glue.
 
Thanks sine! I knew there was something going with the foam panel since I've seen others posting them. Drilling both panels simultaneously is genius! My main concern (besides getting the sheets of ply home in my Grand Cherokee) is keeping stuff lined up during assembly. Hope the web clamp does the job.
 
I personally just draw it straight on the plywood the first time, but doing it on the foam can give you that extra step of "is this right?"

just make sure your braces are the correct size by laying them on the first side in place after you've drawn the cab lines. to insure that they actually *fit* where you put them (braces made sized to the plans, and placed incorrectly will force the cabinet out of square)

I'm scanning through the keystone thread to find info on the braces. there are 9 braces in the cab. some decent pics of arts sketch can be found here @post 63 (link should take you straight there)

http://www.diyaudio.com/forums/subw...ing-18-15-12-inch-speakers-7.html#post2617785
 
I think I will do as you and forgo the foam board, sketch on one side, drill both, then use the sketched side for cutting braces and lining up for assembly. I'm starting to get a good feel for the build.

I am a little unclear about the bevel cuts. Can someone confirm I can cut the horn panels slightly oversize at 90 deg and come back and tweak the bevel? To me, it looks like the cut list is forgiving enough. Great utilization of material!
 
Thanks. 16.6" for the B&C on mine. I just was confused when sine said cutting the baffle out was time consuming... I was worried there was some kind of angled recess that was on your original sketch. Plan to go old school with a jig saw.

I am gonna put off the driver purchase until I am confident of my cab work will be successful. I keep reassuring myself that I made some good sounding auto subs years ago with a circular saw and pocket calculator.
 
I just was confused when sine said cutting the baffle out was time consuming... I was worried there was some kind of angled recess that was on your original sketch. Plan to go old school with a jig saw.
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Jig saws are time consuming compared to circular saws or a router ;).

Using a router with a Jasper jig, a perfect circle can be cut in under 30 seconds.
That said, if you only have one router and it has your round over bit in it, takes longer to change bits and put on the Jasper jig than cut a single speaker hole with a jig saw...
 
spot on art. It'll probably take you more time to DRAW the circle on the board than it will to cut any of the other panels to size (approximatly the time it takes you to adjust the bevel on your table saw plus one minute)

the braces only take time if they dont fit exactly the first time (which can be quite often).

routers are indeed the fastest, but mine esp takes FOREVER to change the bit, so the 3/8 roundover is pretty much permanently installed.

based on the last hornresp inputs posted in the keystone thread, it looks like tbw100 will take about 1000 watts before reaching the 12 mm xmax. the sim does not take into account the extra "cone control" that is exhibited by the keystone mouth opening (or any of the response changes inherent with the keystone mouth). Neverless, with your amp, the hipass knob should be at 33 (JUST shy of 35), and you should use the 125 hz setting for the lopass. This should allow you to pretty much clip your amp at 8 ohms bridge and still be safe (you will exceed xmax with pure sine waves clipping... but the TBW is a sturdy driver, so I wouldnt be too worried). If you have a PEQ, take a 3 db notch out at 133, and another one out at 195 if possible to smooth some peaks.

get the driver dude! We have faith in you!
 
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