Speedster Center Channel

[Mike220]

First I want to thank Paul Carmody for releasing these builds and making them available to everyone.

I built the Speedster TMM's earlier this year and I really love them. I spoke with Paul at IowaDIY and asked if a center channel was ever made or if he intended on making one. He said he would send me a design for it! He thought it was a 4 woofer (MMTMM) but that was the sunflower center and the speedster center was actually still a 2.5 way but in an MTM configuration. I'm kinda glad it was only 2 woofers because the woofers are a little more expensive and I was able to get the OVNS dipoles to round out the setup.

The crossover is the exact same as the speedster TMM's (LOCATED HERE).Paul said you can increase the box size, go sealed etc if needed but this was his recommendation.



I just got this information so I haven't gotten very far yet only an hour or so between the finalist Folded MLTL tower im doing. The build thread will be going up in the next few weeks once it's nearing completion. I actually didn't have much wood on hand so I worked with what scraps I had left I was able to get the sides, slots, back and baffle cut. It is a crazy easy box to build. Just rip a 5 inch board and make all the cuts to length then do the top and bottom at 12x17. just cut the top /bottom last incase your off by a hair. I stopped and got some Aqua coat waterbased clear grain filler (has great reviews and you don't need to match colors since it's clear) and BB ply cabinet grade at Woodcraft it was a 24x30 piece for $22 definitely a lot more than mdf! I was going to veneer the top and bottom in walnut then wrap a more fancy veneer around the middle portions. I'm not certain it's necessary to veneer the Baltic birch ply it looks pretty good but it does look like a extremely thin layer on top. I'm going to Kentucky DIY this weekend so it's likely nothing will be posted for a week or two however there was some interest in this center so I wanted to post something. It's getting cold here fast so I will need to be working inside.

Cut list (3/4" stock)
Dimension Quantity
5"x12" (2) - Sides
5"x8.75" (2) - Slot Port
5"x14.5" (1) - Baffle
5"x15.5" (1) - Back
12"x17" (2) - Top / Bottom






The woofers needed some extra material removed



I used some veneer tamer and "pre-bent" all the veneer with clamps and wood scraps to make the veneering process.







I cut this brace so I didn't snap the 2 sections or the baffle in half scraping the veneer on.



I used some weight, clamps, boards even though its contact cement.












Checking the seams!


Used this on the finalist mid tunnels it's Teak. I have about 24inch x 64inch left it looks great!



Taped the area where the router bit flush trim bearing will run to minimize and marks from it.



For this finish I used a water based grain filler rubbed in with a cloth. It's a gel that dries clear so you don't have to match the color of the wood and only need one. It doesn't fill knots in only the grain it's not really strong enough for holes or chips. Then I sanded to 320-400 and apply varnish














And the finished product

[mattsk8]

Very, very sharp looking! I love the veneer work and the color combo with the exposed endgrain!! I think you told me before, but what contact cement did you use and do you have any do's or don'ts you'd care to share with us regarding veneering with contact cement??

[Mike220]

Yeh, I bought the standard DAP contact cement at menards. I've used the water based and it worked quite well. The benefit is you can use the water based inside without much issue the fumes from the oil based stuff is bad. Definitely use a lot and make sure you get a lot around the sides top/bottom. You tend to put it on the center and go outward so the center sticks very well and the sides get less glue but look like they have a lot. The curves almost require 2 people with contact cement because if you mess up and touch the veneer it's pretty much stuck.

I want to try the iron on method that seems to be an excellent way to adhere, line up and verify great contact to the substrate. As for other tips. I used shellac on the outside/inside of the cabinets to "seal" them but I wouldn't recommend doing that on a substrate your going to veneer. My other projects I didn't have any issues with the veneer bonding but on my Finalists I had a few bubbles and the edges around the removeable baffled have popped. I think this is due to assembling because the gasket material is being sandwiched and pushing the edge of the veneer outward. A few weeks after assemble I need to fix 2 areas were the veneer on the sides is peeling away from the edge slightly. It just takes a drop or two of "crazy glue" with a toothpick or something to spread it around very lightly but it will bond and hold tightly after that.

Iron on seems like an easy way to verify you have good coverage since it looks to be thinner than the contact cement and the contact cement doesn't spread well.

Im not going to lie those corners in the front were the slot port is on the external side did not want to stick. I tried very hard with clamps and whatnot to keep it on but it wouldn't stay. I ended up just using a little epoxy and clamping it in place. It worked really well. It's too bad the whole cabinet can't be done in epoxy. It dries quickly so it probably wouldn't be feasible but I actually had a little bit of working time and I could move the veneer a bit with it.