Carmody Tarkus 3-Way in a one-piece curved cabinet

[Wolf]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

"Carmody's Tarkus" is sounding humorous to me at the moment....:D
Heh,
Wolf

[RINNAV]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

"Carmody's Tarkus" is sounding humorous to me at the moment....:D
Heh,
Wolf

LOL, I didn't think twice about it until you mentioned it--now I am laughing uncontrollably! Thanks Wolf:rolleyes:

Jason

[critofur]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

...I read a few fairly convincing posts by respected builders that crossties are pretty effective...

That's right. And a hardwood cross-tie is substantially better than an MDF shelf brace Even pine is better, as long as the length of the brace follows the grain of the wood.

[Randall Kepley]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Great Job Cowtown, just dont forget to seal the plugs, if you realy thin the solution the 1/4" plugs will suck it up and should not expand and will dissapear. Another good trick to stop movement on something that small would be to go to the dollar store and buy 10 or 15 small bottles of crazy glue, they usually sell it 2 for a dollar and completly saturate both sides of the plugs , it will sink into every crevice, dry hard as chinese math and keep it from absorbing anyform of moisture. Come to think about it I would do this over the thinned poly, you can go wrong. Plus it will dry very fast which means you can get back to sanding the plugs and on to the veneer. Great job so far. R.K.

[jonpike]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

A single layer of 3/4" MDF will resonate/transmit some of the back wave - if you put your hand on it while the speaker's playing, you'll feel some significant vibrations.

Looking good... nice photodoc'in...

If there are concerns with the thickness/stiffness, something you could do fairly easily would be to glue a few "bars" of hardwood, BB or something stiff, against the back of the baffle. Say an inch to inch and a half wide, half inch thick, glue the thin edge to the baffle. Any flexing would have to flex it thru the thicker width. Lots of stiffness added. Probably not as good as a 1.5" thick baffle, but probably a decent improvement. I'd use epoxy, for a really solid joint. Maybe a bit of foam or felt on the sides near the midrange to cut down potential reflections...

Looking at the back of the baffle pic, you could do one between the woofer and mid, between the woofer and the port, and maybe one between the tweeter and woofer, if you did a little filing to make a clearance notch going over the T nuts.

edit: After thinking about it and looking at where the dowels are, the one between port and woofer would be a little redundant. Maybe a couple vertical ones between the outer dowels and the bottom, if one wants to get compulsive... ;-)

[cowtown]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Made some good progress this weekend, to the point where I could actually test-listen to one of them for the first time. It's too early to say how they sound since the other cabinet isn't done, there was no lining installed, and the drivers are still stiff, but the phrase "plenty of bass!" comes to mind.

Gluing the curved sides on was quite a bit harder than I expected it to be. I used two hold-down straps to get the first panel (3/16" tempered HDF) glued onto the skeleton, and it was tricky getting the HDF to seat all the way along the MDF. It wanted pop up and away from parts of the curve. I thought about shooting some brads into it to tack it down, but I want to do a roundover later so clamps were the only way to go. With some struggling it eventually worked out OK, and the following layers were a bit easier.

I re-discovered the old axiom of "you can never have enough clamps," and took a run to Harbor for 6 more after struggling with the first few panels. I still could have used a few more.

Also had a chance to build the crossovers on some thin oak scrap with dowel scraps for legs. They'll sit on the bottom of the cabinet.

Chamfered the mid just so it doesn't nag at me later. Building the sealed MT section:






Crossovers with separate inputs for the W and TM sections:


It's starting to look like a speaker! I haven't done any flush-trimming or roundovers yet, but had to drag it into the living room to see how it looks:

[fastbike1]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Really, really, looking good. Those are going to be outstanding.

[Mark65]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

I'm likin' it...a lot!

Great work!


Mark

[bill poster]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Very nice. Glad to see someone using curves in cabinet builds!

[Randall Kepley]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Cowtown , those are looking fantastic my man! I love the dowel supports , it is far stronger than many would ever think. Cant wait for the veneer work. Keep it coming , were waiting. R.K.

[cantgetitright]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Very nice. Them are going to sound great. Wow.

[cowtown]

A dilemma

Thanks everyone! These have really been a lot of fun to build so far. But I think the really difficult part is ahead....

Thinking about veneer, the original plan was to do a 3/4" roundover on the 4 vertical curved edges, which is what the Sketchup graphic shows. But how would I go about veneering around this? I am realizing that, by doing a roundover there, a compound curve would be created. How the heck could this be covered smoothly?

Another possibility would be to just flush-trim the vertical edges, and veneer the sides and front with separate pieces. But I'd really prefer that the veneer wrapped around the front edges to reinforce the "boat" design.

Fortunately nothing is trimmed or rounded-over yet, so I'll just sit here and wait for the "no problem, it's easy, just do this..." answers to roll in.:D

--Colin

[andykriech]

Re: A dilemma

Thanks everyone! These have really been a lot of fun to build so far. But I think the really difficult part is ahead....

Thinking about veneer, the original plan was to do a 3/4" roundover on the 4 vertical curved edges, which is what the Sketchup graphic shows. But how would I go about veneering around this? I am realizing that, by doing a roundover there, a compound curve would be created. How the heck could this be covered smoothly?

Another possibility would be to just flush-trim the vertical edges, and veneer the sides and front with separate pieces. But I'd really prefer that the veneer wrapped around the front edges to reinforce the "boat" design.

Fortunately nothing is trimmed or rounded-over yet, so I'll just sit here and wait for the "no problem, it's easy, just do this..." answers to roll in.:D

--Colin

Hmmm...that gets tough quickly.
While I know it is mixing modes, a 3/4" chamfer would allow you to veneer the chamfered edge. I do realize that the flat edge isn't keeping to the curved theme, but it is at least easily done.
Check out jclin4's Hold Outs for a recent example or the Drake in the project showcase. This would work on your curved edge, too.

HTH, Andy.

[Pete Schumacher]

Re: A dilemma

Thanks everyone! These have really been a lot of fun to build so far. But I think the really difficult part is ahead....

Thinking about veneer, the original plan was to do a 3/4" roundover on the 4 vertical curved edges, which is what the Sketchup graphic shows. But how would I go about veneering around this? I am realizing that, by doing a roundover there, a compound curve would be created. How the heck could this be covered smoothly?

Another possibility would be to just flush-trim the vertical edges, and veneer the sides and front with separate pieces. But I'd really prefer that the veneer wrapped around the front edges to reinforce the "boat" design.

Fortunately nothing is trimmed or rounded-over yet, so I'll just sit here and wait for the "no problem, it's easy, just do this..." answers to roll in.:D

--Colin

Get some 3/4" hardwood strips and lay them on the edges. Use the router to put a roundover on those, since the strips will likely be able to bend around those large radii.

Or, if you don't mind using oak, you can purchase 3/4" quarter rounds that you could lay on the edges (once prepped by the router).

[denton]

Re: Carmody Tarkus 3-Way in a one-piece curved cabinet

Carmody's Tarkus

I thought it was gonna look like this:



Nice work! I'm waiting for the finished veneer with baited breath.