Tuba 60 Downunder

[PulseMan]

After the wedding I cut 11 and spent out the evening prepping guide boards and and screws to fasten panel 10 and braces.

That's the spirit of a true BFM builder; get's married, then doesn't piss around - straight into cab building. To hell with the honeymoon.

Gotta love it

Ps - sure you're not a kiwi?

Sounds like an ex South African to me....LOL

[Titanium Hand]

Sorry to let you guys down... My wedding was 24th November 2012, the wedding last Saturday was for a friend of my wife

I'm feeling like I've really made some progress this week. Been bogging and sanding the braces along with panel 6, 7, internal of both sides and panel 12. All had 3 coats of duratex except three braces which will get theirs tomorrow morning before I head off to work.

Hopefully I get to glue up 6/12, 7/12 and at least panel 12 & 13 tomorrow afternoon and evening.

No rushing of the business end though

[Grant Bunter]

Sounds like you're making good progress TH.

Looking forward to the end result...

[Titanium Hand]

Wow, painting the braces externally along with rest of the mouth saved me a whole lot of time, if not time - at least frustration.

After finally gluing up panel 12, 6 -12, 7-12 and 13 on Sunday I took it pretty easy today spending only a couple of hours chiseling off PL, sanding and giving the assembled mouth & throat a thorough final coat of Duratex.

I'm so pleased with my curved brace making efforts, along with time spent bogging up the screw holes from fastening to the templates I've gotten a great looking beast.

Got to seal up the wire going to the second pair of jacks tonight so that I may fasten on the final side panel tomorrow after work. I had a quick dry fit up earlier today and I've gone about 2 or 3mm out of square If I don't like how it looks when I clamp it into submission tomorrow I'm going to bite the bullet and buy another sheet of ply which I'll finish up with the flush trim bit. Totally regretting pushing the braces in that eighth of an inch too far.... drats.

On another note I've begun looking at fabricating the access cover flange.

Was the baffle backer supposed to be the full 28 inches wide? As the plans instruct the flange to be made from 3/4 inch strips all around, it appears that where it encounters the baffle backer I will only be adding an additional 1/4 of timber? Have I made a mistake here?

[88h88]

Are you talking about the driver spacer? If so on my first T60 it was almost as wide as panel 3 itself and the flanges sat quite nicely on it at that particular point. This time I've gone just a bit bigger than the driver itself.

[Titanium Hand]

Driver Spacer - That's the one! Only measurement that I read on it was 13 inches, so I made mine 13 inches x 28 inch internal width

I guess the best solution would be to break out the trusty router and flush trim bit with bearing closest to face plate. The bit itself has the ability to cut precisely one inch.

My theory is that by adding an additional piece of ply on top of the cab which would become the template, the router would remove the half inch of driver spacer required for the fitment of flange and as a bonus neatly trim up the access hole where i finished the cut with handsaw.

What do you guys think?

Good solution or perilously risky?

Thanks for your assistance folks

[88h88]

Sounds good to me, you just have to make doubly sure that your router is sat straight so it can chew through the driver spacer at a 90 degree angle to the panel.

[Titanium Hand]

F@#K Me...... I'm worried now whether the baffle itself is a perfect 90 degrees to the side panel

I'm a structural landscaper - Australian Standards dictate + / - 3mm in 1000mm, as a manufacturing tolerance anyway

Here I was looking for excuses to do an access panel on one side only and I think I've found one What to do!

[88h88]

Reaching in and doing up bolts from one side is a complete arse considering the size of the chamber. I imagine if it was a Lab15 it'd be even worse. It's possible depending on the width of the cab but for narrow ones you'd be boned getting enough leverage on the bolts to really crank them down which is where you'd require a nice ball ended allen key setup with a nice grip.

Nothing about these cabs is 'easy' but when you sit down and plan shit out it's easierrrrrr.

[Titanium Hand]

I'm with you 88H88.

My planning and diligence, however thorough - was not thorough enough.

Panel 11, in a daze, has bellied out panel 10. Thus clamping into alignment the pre - cut second side leaves a bit to be desired

After sleeping on it last night and double checking it just then, I've decided that I will purchase an additional sheet of ply and utilize flush trim technology to get best result. Its a costly dilemma, which was easily preventable if I had remained focused upon the plans.

Amateur mistake, certainly not the type of stuff up I'd expect to make on my 5th BF Cab - There is a lesson for everybody here and at risk of getting frowned upon I'll take one for the greater good of mankind....

DON"T DO DRUGS (and expect to build immaculate cabs the next day )

[Titanium Hand]

Well, Wednesday I got rained off from work by 12:30.... So I drove 5 minutes as I was in the area and Purchased a 'Dune Compact green blue & cyan LASER Along With a Smoke machine and stage formula.

Pretty excited about this party I'm doing overlooking the beach on the 21st. My T39's would have been way overkill, T60 will be brutal I imagine. Laser and Smoke machine will round off the package nicely.

The rest of the afternoon I went and purchased another sheet of stunning Finnish Birch along with s selection of screws from Bomond.

Tonight I rough cut out the new side piece, marked and cut out the second access panel. Masked and gave 3 coats of duratex to mouth area on seconds side.
I also re-visited the access panel flange screw up. i added an additional piece of ply as a temporary guide and trimmed off precisely 5/8 of an inch from the Baffle Spacer to accommodate the flange. I really dig my router!

Tomorrow I'll be fitting the second side woo hoo! I forecast noise on Sunday afternoon

[88h88]

Noice, I hope to get my second to a point where I just need to pop the side on very soon (Saturday hopefully). Custom braces are nice but man they waste time.

You'll love it, believe.

[Titanium Hand]

88H88 your spot on there!

They have probably cost me at least an additional 3 days worth of building time (not 8 hour days but snippets of evening building time)

Given the reports of the 'Mouth Blast Zone' when placement law allows I want to take advantage of this and have something trick for the punters to look at too

Curves remind me of women

Off to operating room to glue this second side up gents, wish me luck! ! !

[Titanium Hand]

Well my weekend was a blur of PL Fumes, Birch Dust, Router Noise, Bondo and phone calls from my wife She was away for her 'Honors'

Gluing; Is all done.

Cutting; Is all done.

Bondo'ing; Is all done.

Sanding; 80% Complete.

Acquisitions 85% Complete. I've got angry looking 'star' washers for the driver. A plethora of machine washers for the DUAL access covers, Square Drive Stainless Steel #10 Decking Screws for Driver, Phillips Head #10 Stainless Screws for the access covers, Trojan stumpy ratchet multi-screw driver gadget with 10mm Hex head for Spanner tightening abilities.

I still require corners and gasket tape. Haven't been able to find suitable Black screws for the jacks and corners so I've purchased some nice stainless ones to complement the access covers.

I'm toying with the idea of having aluminum u-channel lining the horn mouth and a 12 & 15mm L-Strip For the top, undecided though. Any thoughts all?

Would have to go for nondescript chrome corners to make it integrate though and polish the aluminum.... The list goes on.

I sanded for two entire hours by hand when I got home from work this evening, going to get into it again now.

[Titanium Hand]

Rounding Off - Done! I've learned that the best way to round off is by going into the cut face of the ply (can see all 9 ply) opposed to into the panel face itself. No tear out. No burning. No dangerous grabbing either

Even oiled the cutting bit bearing first.

I did some additional sanding, making it look a million bucks.... Along with a bit more bondo-ing Very satisfied with the beautiful result.

Half an hour later, after a quick dinner, I gave her the first coat of Duratex. The 5 inch foam roller I have worked great on my o-tops and titans however I feel that its a bit under gunned on the T60. Might have to get a bigger roller for final two coats.

My access panels have me scratching my head. With 1/8 inch gap evenly spread around the cover I'm left with around 5/8 at best of access cover overlapping the 5/8 at best of flange. Center of that would be 5/16. Not a whole lot of meat for the screws to grab into.

I've marked up and screwed together on scrap ply for a test. 1 of the 4 I tried splintered and lifted the top ply Glad it was only scrap. Bigger washers still, didn't alleviate this issue.

I purchased a 3m length of 3/4 inch wide 1/8 inch thick strip of Aluminum. I plan to use this as a 'mending plate' or external flange , flange. My theory is that it will distribute the effort of the screws more evenly along the timber. Even if the timber still 'tears out' when torquing up the screws, it will be hidden by the flat bar. Looking neat and tidy.

Given the thickness of aluminum strip ( I should have gotten 1 / 16th thick ) I'm considering recessing it into the access panel so its flush.

Would the removal of 1/8 inch deep by 3/4 inch wide strip of the ply around the perimeter of the access panel weaken the ply itself to much? I think it would look hella trick!

Any theories? Ta