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Discussion Starter #1 (Edited)
I "finished" my home theater a few months ago, which left me speakerless in the living room (1899's moved into theater), so I've decided to build a pair of Uluwatu's for music in the main living area. I have officially joined the "WAF" club, so I now must consider how all future speaker builds will affect her :) I've built dozens of square/rectangular cabinets, but I've decided to step my game up and attempt to build some curved towers. I am also going to try to veneer these cabinets. No experience with building curves or veneering, so I'm open to any advice/tips/tricks I can get. Special thanks to @dtsdig, @PassingInterest, and others for inspiration and posting their experiences with building curves and veneering.

I have stared the build, I'll post progress below. Here's my hi-tech paint sketch for the curved braces. I made the widest part of the cabinet a little wider than what was recommended by Curt, but overall I will lose some internal volume, with that curvature near the rear baffle.



EDIT (2-2-17): Speakers are finished! Final pics below:













 

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Discussion Starter #3
Using 3/4" mdf for straight pieces and 3 or 4 layers of 3/16" hardboard for the curved sides. The transmission line baffle made the brace cutting a little more tricky. I used a whole piece for the transmission line baffle and plan to attach the curved braces on both sides.

Glued down baffle sketch and cut out my templates with the band saw. Sanded the templates until they were smooth, then used a router with flush bit to make all remaining braces identical.





Next, I cut out the front, middle and rear baffles. All 3 needed angles sides. I didn't do any actual math to figure out the angles...just used the brace templates to get close.


 

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Discussion Starter #8
Looking great so far! What's the final height going to be? My 50 inch tall 1099's weigh almost 150 pounds each! Lol
Thanks man. Final height is 47". That's ridiculous lol. I had to purchase a dolly to move the 1899's around, so luckily I'll have that for these towers. Although I imagine I'll be scared to death to move them once I have the veneer and finish applied.

That's a great looking skeleton. If you have PassingInterest's thread bookmarked, you've got a pretty good resource, so I think these are going to turn out great. Keep posting pics as you go!
Thank you! For sure, I'll be referring back to his thread for info on applying the finish.
 

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Sweet, I hope same curve build works nice for my future subwoofer. :D
 
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Discussion Starter #11
I ordered veneer already, it got here yesterday. I bought 6 x sheets of "curly ash" with dimensions of 96"x16". Way more than I need, but wanted to have enough in case I screw up somewhere. It was some of the biggest sheets I could find (won't have to splice anything together) for a decent price. Came out to around $100 for all 6 sheets. I am hoping to stain the veneer some shade of cherry as well. I knows there's tricks to make the grain pop, so if anybody has any advice on that procedure, feel free to post. I should have plenty of extra veneer to test stain and finishing on.

One concern I have is that the veneer is a little bit "wavy", especially near the middle, with the thicker grain. It's not terrible (maybe 1/4" of spread near the most wavy part), but I wonder if it's something I'll be able to correct when I apply it, or if it's something I need to correct before I adhere it. Veneer is 1/42" thick. 2 suggestions I received: 1. Wet the veneer, press it flat, wait to dry, then apply with contact cement. 2. Wet the veneer, adhere it to speaker with titlebond (water based) while the veneer is still wet. Or maybe the warp isn't bad enough to where I can just roll and flatten it out with contact cement.

 

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Looking good so far. I had a lot of fun building my curved mains and they are what people notice first when they enter the room. Mine are also built mostly from MDf except for the top and bottom which are Baltic birch. I did this for sturdiness when moving them around while I was building them since mdf chips so easily. Also just in case some water got under them even though I used 1/2" rubber feet. Have fun!
 

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Discussion Starter #14
I also got the first layers of hardboard glued on the sides. Made some mistakes, learned some lessons. My first fail was using titlebond to glue down the initial curved layer. I knew I was supposed to use PL premium, but it somehow slipped my mind when I got going. It held the hardboard down ok, but one corner didn't get fully sealed up. I quickly realized I was supposed to use PL, so that those small gaps would be filled out better. I went ahead and ripped that layer off :( and took the belt sander to clean up all the ribs. I used PL on the next attempt, but I had alot of trouble figuring out the best way to get the hardboard clamped down straight and pretty. Using just raw straps, it left "ripples". I tried to correct that by using straight edges (1" square aluminum pipe) on both ends of the hardboard, underneath the straps, but the pipes kept wanting to slide toward the middle. I also tried to apply clamps during all of this, but the angle was too steep in the rear for the clamps to hold. I finally broke down and built a jig out of some lumber I had laying around(should have started with this). Now the strap angle applies force directly down onto my pipes and they don't slide around. With the jig, the whole process is about 10x easier, and I'm getting perfect contact and seal on all edges :) I won't post pics of all my failed attempts lol.





The other thing I love about PL is that it doesn't run all over the place. Nice clean beads squeezed out everywhere.


Stuffed acoustafill in the transmission line since I won't have access later.






I built a plunge jig to flush trim the spare hardboard. You can see I had a little trouble getting it adjusted properly lol. Will have to correct some of that with bondo.
 

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Discussion Starter #16
Yay! You built my jig! Like you said, you should have done that to begin with, haha. It makes it so much easier. How many layers are you doing for the sides?
Lol what's funny is I could NOT find a pic of your jig, even digging through google pics. But I remembered enough of it when you posted it way back when, so ya, thanks for the help on that. As for layers, that's my next question. I've been talking with the guy I bought the veneer from (Joe from veneer supplies) and he's put some serious fear into me about veneering on hardboard. I know you and others have done it with no problems, but I guess I would sleep better at night if I go ahead and make my final side layers 1/4" plywood. A full sheet is only $18 from home depot, and with my strap jig I'm pretty sure I can bend anything lol. So right now, I'm thinking 2 layers of hardboard, and 1 layers of 1/4" plywood. If there's any reason to not do this, lmk.

Joe also talked me out of contact cement haha. Since I have "raw veneer" (not paper back), he highly recommended using actual veneer glue. The cold press glue he sells is about the same cost as contact cement anyway, so I went ahead and ordered a gallon from him. I'm nervous about gluing the veneer down. For the flat sides, I'll use scraps of MDF and tons of clamps to press it down. For the curves sides, I'm thinking I'll use the strap jig and layers of spare hardboard to apply pressure. Open to suggestions on this as well.
 

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Discussion Starter #17
So I'm pretty far from applying a finish to the veneer but I'd like to game plan and start testing on pieces of the ash veneer I have. I've done a ton of reading, but I'm still trying to better understand the whole process. I am going to want to apply color. I'm going for a reddish brown, but not too dark. I really like the idea of using dyes, because of the freedom to create the shade you want as well as apply multiple layers to keep adding color/shade. I'm also hoping to get the grain to "pop" as much as possible. I read about grain filler, but most reviews I read said it can be difficult to get grain filler to match the final tone of the whole project.

I went to woodcraft to get some advice, but the guy there recommended oil stains and top coating with urethane. I'd have to wipe/brush both of those and I'd way rather spray. So I think I'd rather try the shellac + water based polyurethane many users here have used.

Here's what I'm thinking so far. Basically what PassingInterest does:

1. Apply 1 or 2 coats of Zinsser SealCoat Shellac. What's the purpose of applying this non-dyed layer first, before dye?
2. Apply some number of layers of dyed shellac. Or use dye+water/alcohol here?
3. Apply some number of layers of "Gloss Minwax Water-Based Oil-Modified Polyurethane" to achieve level of gloss desired. Does poly need to be thinned to spray?

One issue I read about was when dying ash, users had a hard time getting dyes to penetrate into pores. Will the initial layer of shellac help keep this from happening?

Another question I have is about dying using water and/or alcohol as your substrate, or mixing it into shellac. Some guys have the opinion that dye in shellac won't actually penetrate the wood, but simply leave tinted layers. I'm not opposed to that, but which method might be easier for a beginner sprayer? I've sprayed before, but def need some practice. I will likely use the cheapo HVLP gun from harbor freight.

Thanks in advance for any tips.
 

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Nice work.
I'll be watching this with interest as I'm prototyping for a build next year where the front and rear panels are curved; it'll look reminiscent of a SF Stradivari, but the rear will be deeper with more of a V x-section. I've never done a curved build so I'm scouring all the old threads for tips.
 
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Discussion Starter #19
Spent all week getting layers glue up. Ended up going with 3 layers of 3/16" hardboard (Masonite), followed with an outer layer of 1/4" plywood (cheapo Home Depot stuff). This came out to an actual thickness of just under 3/4", so I'm pretty happy with it. The cabs are now already crazy heavy. On my first attempt at gluing the 1/4" plywood on, not thinking about it, I clamped it down with the grain perpendicular to the cabinet. As I cranked it down, I broke the sheet in half lol. I then realized it was much easier to bend the plywood parallel to the grain, imagine that lol. It wasn't as easy to clamp down as the hardboard, but it shaped up nicely. I trimmed up the cabs and sanded it all down. Really happy with them so far.





Got the holes cut out too


 
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