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Another T39 build
Posted: Sun Nov 29, 2015 5:59 pm
by ctmullins
Okay, it's official!
As discussed in
my inquiry thread, today I started work on my BFM PA. I'm strongly leaning towards Otop12s for the tops, but not completely sure yet. So I figured the subs would be a good place to start!
Not much to show, but it is proof that the build is underway - panels cut to rough dimensions! After dinner I'll sharpen my pencil and begin marking the sides. Doubt I'll glue anything up tonight, and tomorrow it's back to the day job.

Re: Another T39 build
Posted: Mon Nov 30, 2015 10:57 am
by J_Dunavin
Good start!
Keep plugging away, just a little bit every night, it'll be done before ya know it.
Re: Another T39 build
Posted: Sun Dec 06, 2015 6:28 pm
by ctmullins
Thanks for the encouragement, J, but wow, what a hella busy and exhausting work week I had!
Had a little bit of time on Saturday though. Got the top (panel 1) and the baffle (panel 2) cut out to spec. My router slipped a bit when making one of the hand holds; will have to figure out how to fix that.
Then, after that amazing amount of progress, last night I re-read the text describing how to do the baffle and the driver anchor, and after consulting SketchUp, realized that I had it all completely wrong.

I didn't realize that the driver is actually inlaid into the baffle, and screwed only to the anchor behind it. So today started with me trying to fix that with my little laminate router.
Tedious and time-consuming, but it worked.
Dry fit everything and checked for square, pretty good so far, but we're just getting started.... Then made a mess with PL.
That's all for this weekend, and next week promises to be hellaciously busy at the day job again.....
Re: Another T39 build
Posted: Tue Dec 08, 2015 9:20 pm
by ctmullins
Panels 3 and 4 fitted this evening! Numerous little scrap jigs and clamps used to hold the panels while the PL sets. I actually added a couple more after this shot was taken:
I love this little spreader clamp!

Re: Another T39 build
Posted: Wed Dec 09, 2015 12:58 am
by Tom Smit
I love this little spreader clamp!
Yup, they are handy, aren't they?
Re: Another T39 build
Posted: Wed Dec 09, 2015 10:03 am
by CoronaOperator
ctmullins wrote:Panels 3 and 4 fitted this evening! Numerous little scrap jigs and clamps used to hold the panels while the PL sets. I actually added a couple more after this shot was taken:
That looks about the same number of scrap jigs as when I built my subs. I see insulation, are you in an attic

? You are only supposed to build your tops in the attic, subs are supposed to be built in the basement

!
Re: Another T39 build
Posted: Wed Dec 09, 2015 12:22 pm
by ctmullins
CoronaOperator wrote:
That looks about the same number of scrap jigs as when I built my subs. I see insulation, are you in an attic

? You are only supposed to build your tops in the attic, subs are supposed to be built in the basement

!
Ha ha! Yep, our house has a barn roof, so the attic is massive! It's currently unfinished, but I have a drill press, a small table saw, and a drafting table/workbench up there, as well as good lighting that I installed, so it works well. Of course, it's only usable during half the year, as our brutal six-month summers here mean 120+ temps up there. No basements in the Gulf South, they'd just be full of swamp water anyway.
I'm building 24" T39s, so they should fit through the door after they're built.
Ordered 3012LFs, casters, and skid rails from Leland this morning!

Re: Another T39 build
Posted: Wed Dec 09, 2015 3:02 pm
by Grant Bunter
ctmullins wrote:
I'm building 24" T39s, so they should fit through the door after they're built.
Don't forget they are only 19 1/2" deep.
Turn em sideways to get them through doors if needed...
Re: Another T39 build
Posted: Sun Dec 13, 2015 6:19 pm
by ctmullins
Panels 5 and 6, and their associated braces, fitted today! I swiss-cheesed the braces, not that it helps much, but the drill press was sitting right there...
I must not have understood the plans regarding panel 6. The measured length shows as 17 3/8", but the required length, when I went to test-fit, was 16 3/4".

I double-checked Sketchup, cut it down to 16 3/4", and glued it in.
The panel 6 extension is not glued in yet, although it appears in the photo, astride the driver chamber...
How many more cabs will I need to build before I don't make a complete mess with the PL?

Re: Another T39 build
Posted: Tue Dec 15, 2015 7:56 am
by LelandCrooks
ctmullins wrote:
How many more cabs will I need to build before I don't make a complete mess with the PL?

Many.

Re: Another T39 build
Posted: Tue Dec 15, 2015 9:49 am
by ripNdeb
So true. That 'mess' is a part of the no-air-leaks solution.
Re: Another T39 build
Posted: Tue Dec 15, 2015 10:47 pm
by ctmullins
Baby steps...
Here's the collection of clamps and guideboards necessary to keep the panel 6 extension in place while the PL sets. I had hoped to do the flanges as well, but there's no way to do that until the panel 6 extension is fully glued in...
My fabulous spreader clamp makes another appearance!

Re: Another T39 build
Posted: Thu Dec 17, 2015 8:43 am
by ctmullins
Slowly getting the "fiddly bits" (access panel flanges and associated tiny little braces) done...

Re: Another T39 build
Posted: Thu Dec 17, 2015 10:50 pm
by ctmullins
Installed panels 7 tonight. I'm not real happy with them, as I slightly dislodged one of my vertical flanges while trying to nail one of the panels 7 to it.

I clamp-partied it all back into alignment well enough, but I'm going to have to go back in and check it after the PL cures, and maybe reapply some PL to it.
I'm considering consolidating a few of these smaller pieces into some larger ones for the companion T39. Might be a bit more wasteful, but hopefully not much.
No pics 'cause I'm grumpy.

Re: Another T39 build
Posted: Sun Dec 20, 2015 6:53 pm
by ctmullins
Well, the panels 7 and the flanges seem to be okay. I'll probably go over them with another bead of PL just to make sure they're sealed.
Fitted panel 8 (the back) and associated braces today. This is a big panel, and it was warped, which necessitated clamping on a large, long caul of rock maple, leftover from one of my bass builds. Came out nice and square though! Swiss-cheesed the braces again, just 'cause.
I was a little surprised to discover that my panel 8 is a half-inch too long! Double-checked the plans, and the Sketchup, and yep, panel 8 is cut to 39" early on, but measures out at 38.5" in Sketchup, so I guess I was supposed to trim it down. I didn't. I'll do it later.
