Building a curved sided Modula MT

[Outfitter]

I'm sure that I know the answer, but I think it's worth asking anyway. Should I add another shelf brace to the inside of the enclosure?

My dilemma is that I am dangerously low on internal volume. Right now I am exactly at the necessary volume for the speaker. From the base to the brace is 9.5". I was thinking I could put one near the bottom of the rs180, but I also don't want to limit air flow around the woofer. If I do it that way, I would have to remove the front part of the brace, and it would slide around the woofer.
Thoughts?

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Edit, title renamed by moderator to reflect full content of thread

[ThomasW]

I think what you have is just fine.... :T

[Outfitter]

Awesome! Thanks Thomas, and I thought you would say to add more. Later today I will layer up the sides and then it will really start looking like a speaker!

[joecarrow]

The curved walls add a lot of stiffness. It should be an awesome speaker! Is the front going to be thicker?

[Outfitter]

The front baffle is only 1/2" at this point. I cut the baffle holes and chamfer in anticipation of wrapping the sides. I am going to be adding a 3/4" piece to the baffle after the sides are added, for a total of 1.25".

[nerd of nerds]

Do you have any cabinet drawings or plans for this?

I'm very very interested in this as i'll be building the modula mt in a few days (the crossovers are done, just waiting on one part from PE I forgot to order) and was planning on doing the standard box, but this really interests me...so pretty!

I bet they'll look awesome!

[Outfitter]

Sorry, but I adapted it from the template that Mike123 made for his RS WWMT. (Which was originally created by Brian?). Mike sent it to me at the end of the summer and I used it as a template.

I did make changes, the front is 8.5", the back is 4.5" and then used the radius to draw a line between the two points. The length is 12.5". I then used the the interior cutouts as is for the shelf brace.

I am going to laminate each side with 3/4" ply giving finished external dimensions of the baffle the same as designed. 10" wide by 17" tall.

[JonP]

They're going to be gorgeous... :T

I'm soon to be building a pair for a wedding present... and I've also been seriously looking at the curved side construction. (as if my woodworking skills aren't challenged enough!)

Keep us posted.. I want to see how they go.

Oh, about the only thing I'd think you might want to add in the bracing department might be a bit of something for the top and bottom... hardwood dowels, or a few inches wide of vertical board up and down from the center brace. Then you have some support for top and bottom, and it won't add that much more volume. Those sides will be pretty solid from the curves.

Of course there's a port to go thru there to avoid, if you're not making them sealed...

[Outfitter]

Here's a quick update of wrapping the sides. I was only able to find 5/16" "wiggle board" from my local lumber distributor. I am going to use 2 layers, and them I am going to 1 layer of 1/8" masonite(hard board) to get the width to 3/4."

I used 4 ratcheting tie downs to bend and compress the ply. I used about 4-6 brad nails to hold the ply in place while I tightened them up.

I am not very impressed with the bending ply, it is quite rough and has a number of imperfections. The masonite will give a silky smooth exterior that will be perfect for gluing the veneer!

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[ThomasW]

Looking good.... :T

Any bender board I've ever seen was quite rough. It's intended use for curved front counters or the like. These are typically covered with high-pressure laminate or carpet. So the rough surface just increases the bond by holding more adhesive.

[Ecir38]

Outfitter, those are going to look great! I am curious how does one flush trim something like that.

BR

[augerpro]

Keep the pics coming Outfitter! ;x( I really like the look!

[tdv]

modula

Nice work outfitter !! I am also doing a rounded version, just about ready for the black walnut veneer. I still have to roundover the port but that will be done after the veneer. I am debating if I want to add a maple stripe off set on the front like Sam's Orchids presented at the Iowa DIY, nice job Sam http://home.mchsi.com/~dpeterson/Iowadiy.html. This is my second round of Modula's, the first made out of cherry and seas, this one will be rs28. Thanks Jon for your excellent work/design.

[Outfitter]

Looks good, TDV. What kind of wood did you use to bend the outside curves?
It looks like the outside is mdf, did you build up multiple layers?

[tdv]

Looks good, TDV. What kind of wood did you use to bend the outside curves?
It looks like the outside is mdf, did you build up multiple layers?

I used 3/4" - 13 ply and made kerf cuts to make the bend, I then covered everything with 1/8" mdf hardboard. My front baffle is 1 1/4" mdf. I could not find the bendable ply, but will have to soon as I will be building the TMWW using Mike's (m1ke323) template.

[Outfitter]

Small Update!

Here's a couple pics of where I stand. I still need to wood putty the nail holes on the side, and clean up a couple spots I got sloppy with the router. I chipped out a couple edges of the bending ply, that I still need to fill also. By the end of the weekend, I hope to have the front baffle cut and routered. I also attached a photo of the inside walls and back with the dampening. I still need to add a layer to the top and bottom. Slowly but surely, I'll get 'em done.

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[JonMarsh]

You're making nice progress- thanks for sharing with everyone else how you're doing this.

~Jon

[EDS]

is it just me or do your speakers look huge!?

Comparing the speaker to the floor mat and the floor mat to the door!

[Outfitter]

Perception...the angle of the photo is a bit deceiving. Also, the holes in the baffle are the cut outs only, not the recess for the outer edge of the speaker. The hole for the woofer is only 5.75" and the outside dimensions of the rs180 is 7 1/8". The front baffle is the same as a square box 17"h x 10"w. It will be about 1.5" deeper that than the PE cabinet to make up for the volume lost to the curved sides.

[tdv]

modula

Outfitter looking very good ! I had the ply tear out problem also and found it easier to apply that 1/8" layer of HDF before applying veneer. I finished applying my black walnut veneer today and painted all cutout holes black. The 1/8" HDF helped by keeping very true square edges when applying veneer, will post pictures soon. I like your curved design better than mine but the damage is done.

[tdv]

curved modula

Made some progress on my curved Modulas today. Finished sanding the black walnut veneer and applied one coat of BLO. The boiled linseed oil really brings the walnut to life, this can be seen in the before and after pictures below. I will apply a coat of shellac followed by two coats of varnish (not poly). I also finished my crossover assembly and installed them in the cabinets. Can't wait to fire them up, but will probably wait till the cabinets are finished.

[Outfitter]

Gluing on the front baffles....

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[technimac]

TDV,
That Walnut is beautifully done! :T
Nice job on matching the veneer - that adds hugely to the "professional" finish look that you have achieved.

Outfitter,
You must be pleased to have those baffles glued on. Everything looks "good to go" for the last layer. :sn

You guys have done such a nice job that now I'm wanting to build another pair of Modula MT's, but this time they'll be curvilinear! :W

Cheers, Bruce

[kano32]

I'm just curious how you flush trimmed the curved sides to the front baffle. Looking good so far.

[tdv]

How To

I'm just curious how you flush trimmed the curved sides to the front baffle. Looking good so far.

I can't answer for Outfitter but I used a 3/4" top bearing straight router bit. Used a 1" high straight edge for the bearing to follow and set the depth of the router to 1". Place the straight edge across the top and bottom panels of the baffle and run the router down the sides to be trimmed. Maybe hard to understand, I can take a picture if needed.

[Brian Bunge]

Yeah, I think a pic would be very helpful, at least for me!

[kano32]

I can't answer for Outfitter but I used a 3/4" top bearing straight router bit. Used a 1" high straight edge for the bearing to follow and set the depth of the router to 1". Place the straight edge across the top and bottom panels of the baffle and run the router down the sides to be trimmed. Maybe hard to understand, I can take a picture if needed.

Yeah, a picture would be helpful.

Thanks

[Outfitter]

What I did was use a piece of 3/4" MDF, and placed my router on top of that. I set the depth to a hair above 3/4" and trimmed the excess off the top. It may not be the best way, but it worked for me.

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[Outfitter]

I was able to get the baffle glued, and rounded over the baffle. It was a bit more challenging than I had thought. The side walls taper away from the baffle, so I was unable to get the proper roundover across all 4 sides. It took a little hand shaping with some sandpaper, but I think the extra work was worth it.

It's kind of hard to see in this pic, but the bearing sits on the curved side at a wider point than the baffle edge.

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And here are a couple update images...

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[WillyD]

Fantastic work, Outfitter.

[Brian Bunge]

What I did was use a piece of 3/4" MDF, and placed my router on top of that. I set the depth to a hair above 3/4" and trimmed the excess off the top. It may not be the best way, but it worked for me.
]

I'm still a bit confused. What I wanted to know was how you were able to hold the router/router bit perpendicular to the inner front baffle in order to trim the excess overhang from the sides before gluing on the outer baffle.

[tdv]

trimming

hope the photos help explain.

[Brian Bunge]

DUH!!! OK, I get it now! Thanks!

[Ecir38]

DUH!!! OK, I get it now! Thanks!

I had no clue either, thanks tdv and outfitter

[yousuredo2]

I dont understand, & I have done it...
the front is straight, the sides are curved (noy 90 deg.) the bit is straight (90 deg.)

I had to make a spacer/Jig for my router to sit slanted, and sand or plane it to perfection...

I never thought about doing it the way you did, glad it worked for you...

[JoshK]

in the words of Borat....very niiice.

[Ecir38]

Nice change Thomas

[Outfitter]

After a busy couple days, here is the latest....

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Still need to add the binding posts.

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I flush mounted the Precision Port on the back, I ended up using what they consider the inside flare, the external ended up being too wide.

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[Ecir38]

great job, they are awesome!!

[ThomasW]

Those look great.... :T

[WillyD]

Those are utterly amazing!

Great work.

[cobbpa]

Boo-yah / domination / jealousy.

Things like this always make me want to build more, to hone the skills.

[Bent]

best I've seen.

I flushmounted the Precision Port on the back, I ended up using what they consider the inside flare, the external ended up being too wide.

does this mean you used the outer flare on the inside? or is it just a terminated tube?

[Outfitter]

Bent- I have the larger outside flare on the inside currently. It has the same radius, just a larger flange. I doubt that it will effect the port, if it does I will try and trim it.

[BigJim_inFLA]

Excellent work! Those look beautiful.