Docere MLTL - build thread

[meniscus]

Looking good so far! Can't wait to see / hear these.

Mark

[bkeane1259]

So on Saturday I put two fairly heavy coats of shellac on the cabinet panels that will eventually be veneered. Zinsser dewaxed shellac is simply the best unless you're into doing your own with concoction with flakes. I just brushed it on with a throwaway brush.



Today I sanded with 320 and 400 grit paper to make sure the substrate was as smooth as possible. Even at the end grain it's even and smooth as a baby's bottom after the shellac application. This is necessary for the PSA veneer to stick well. It's very finicky and it doesn't adhere well to bare wood and certainly not to end grain.



Also touched up some imperfections with my good friend Mr. Bondo.



Went ahead and Duratexed the Backs and bottoms. After I veneer, I might end up adding an additional coat. Have to see what it looks like. I resanded the edges where the Duratex sort of overlapped to ensure there are no high spots when I lay down the veneer. I applied the Duratex in the sun, fully knowing that you're NOT supposed to. I wanted to see just how quickly this stuff dries. My advice is NOT to apply it in the sun...ever. I was sanding within 10 minutes and reapplying additional coats. You have to work EXTREMELY fast under the sun. Duratex will gunk up on you by the time you get to the end of the panel if you're slow.





A closeup of the texture. I used a smooth foam roller (six-inch). I didn't want an aggressive texture.

[kenny_k]

Lovely...........Lovely.............Loving it.
Go Bryan Go!

[bkeane1259]

Haha....thanks Kenny.

[bkeane1259]

With the help of my 20yr old (Sean) we veneered the cabinets today. Oh and great weather in Chicago for a change

We're using PSA cherry veneer that I had left over from my last tower project. Using leftovers, we don't have the luxury of lining up the grain too well, so these won't have a "wrap around" matching grain effect but we did the best we could and it of course will look better than the bare plywood.



With PSA veneer, you only need to firmly press the veneer onto the substrate with a "scraper" tool. It works surprsingly well despite how simple it is. http://tinyurl.com/k4czua4



Here you can see how the grain pattern on the top of the cabinet doesn't line up with the sides but who pays attention to that?



I used to painstakingly try to trim the excess veneer as close as possible by hand (with an exacto knife or veneer saw) but it's actually easier to just trim it "close" and then run the router with a flush trim bit to get the edges perfect. I don't remember where I read about this, but a good trick to protect the unfinished veneer from being scratched by the router is to put down some contact paper before you flush trim. The contact paper sticks well but is easily removed after your run the router across the panel. My wife always buys too much of this crap, so we have lots of leftovers to use for this purpose. For the point where the flush trim bit bearing contacts the adjacent panel, I stick a strip of masking tape.





I was curious how the veneer would look against the black Duratexed back panels and it's actually not bad at all. The eventual owner of these will have them almost right up against the wall, so the back panels will never be seen. Why waste expensive veneer on them?





I'll be finishing the veneer with Waterlox. It's super easy to use and I should be able to get several coats on before InDIYana....so they won't be naked after all!! http://tinyurl.com/mshhhef

[bkeane1259]

Here's a very short video that shows how easy it is to apply PSA veneer. The key is having a helping hand and making sure your initial sticking point on the panel is correct. The 3M adhesive is VERY strong. Once you stick, you gotta commit!!

https://www.youtube.com/watch?v=FgAxVUabkBg

[bkeane1259]

I mentioned in an earlier post that I have yet to unbox some tools and DIY supplies and apparently my Waterlox is one of those items that's still packed away somewhere!! With InDIYana right around the corner, I don't really have time (or motivation) to go to storage and rifle thru a bunch of boxes, so I grabbed what was left of some MinWax PolyShades finish that I used late last year to restore an office desktop. The (eventual) new owner of the Docere MLTL currently has some old school Cerwin Vegas that have a similar finish. It will be satin, so it's going to be a duller finish than Waterlox but that's not a deal breaker. In fact, I'm pretty happy with the outcome so far.

Seeing that the PolyShades product is a stain+poly, I prepped the cheery veneer with a highly diluted dewaxed shellac coating (like 5 parts denatured alcohol to 1 part shellac). Brushed that on really quick...let it dry and sanded with 220. This prep helps to reduce blotching, which can get bad in cherry veneer. Wiped the cabinets down with a clean alcohol-dipped rag to get rid of any dust and then I applied the first coat of PolyShades.



The first coat is pretty thin. Inspecting it in sunlight reveals a bit of unevenness, which is most likely due to poor garage lighting and my crappy brushing skills. Tomorrow I will sand this lightly with 220 and apply a second coat.



I used this veneer on my Seas Trym MLTL which I stained and varnished and I had a hell of a time dealing with severe blotchiness. So far with this first coat of stain+poly, I cannot complain about blotches.

[bkeane1259]

Unfinished veneer vs. one coat of PolyShades satin pecan

[bkeane1259]

Second coat applied today. This polyshades stuff goes on really thin and definitely requires multiple coats. When I used it on the desktop, it was easier because the surface was horizontal. I'm finding out that this product isn't as friendly on verticals. It runs very easily making thin multiple coats necessary.

Sanded the original coat with 220 and A LOT of it came right off....ugh.



Applied a second coat and since the grain is mostly sealed with the first coat, the polyshades product ran on me multiple times. I had to really be careful.



After an hour of dry time:



I think I'm going to squeak one more coat on before Indy. However, I could see myself adding a few more afterwards. Yeah right.

[bkeane1259]

Crossovers done:



Terminal cups installed. The XOs are glued to the inside bottom panel and the terminal cup is about 3" up from the bottom.



Ran the driver leads up thru the brace holes and zipped them up on each brace.



Just need to stuff the line, glue, flush trim and roundover the front baffle, slap some Duratex on it and install the drivers. Easy.

[bkeane1259]

More progress........

Line stuffed to two inches below the woofer where I conveniently located a brace to mark the end of the line. I ended up using 18 pieces of Meniscus bonded dacron. Five of the pieces are a bit smaller to allow room for the magnet of the Eclipse midbass unit.



One "slice" of dacron:



Oversized baffle glued and screwed onto the cabinet. This will not be removeable. I will bondo over the screws.



Side view of attached baffle before flush trimming:



I've got 1/4" of overhang to flush trim.



After the initial flush trimming with the large bit. I will go over it again with a smaller bit to get it perfectly flush with the veneer after I do the roundover. The blue painter's tape that I use to protect the finish doesn't allow a perfectly flush baffle so I can either do some sanding or use a smaller bit with no masking tape or possibly I'll try the shelf liner for protection. That's actually thinner than the masking tape. I'll deal with it tomorrow.



Ran into a little snafu with my large flush trim bit. Ugh. Discussing it on PETT here: http://techtalk.parts-express.com/showt ... hich-is-it





Fairly large roundover - almost 3/4" -- This leaves me with minimal material to flush trim perfectly up to the veneer line. So I'll probably hit it with the smaller flush trim bit using shelf liner for finish protection. Notice the shelf liner on the top of the baffle. It sticks good enough to run the router over and it covers all the driver cutouts. This ensures the plywood and mdf dust only hit me and doesn't fly into the cabinet. Win win.

[bkeane1259]

Coming down to the wire...... I almost decided to bring them to Indy with a naked front baffle but I'm hell-bent on getting them looking semi-pretty for the show, so here goes.

Ran a smaller flush trim bit over the front baffle without any protection on the side panels. Nice and even now.



Bondo over the front baffle screws.



....and some sanding and more bondo.



A little more sanding and bondo.



Time for my favorite paint in the whole universe - Duratex!!



I will sand this first coat tomorrow and add another. Also have some patch work to do on the roundovers in the plywood endgrain, so more bondo work on the docket as well for tomorrow. Basic plywood never rounds over gracefully it seems, but a little bondo and a couple more coats of Duratex will really even them out.

[bkeane1259]

Today's last minute progress.

Patched up the roundovers with bondo. The next time I do a constrained layer baffle I think I will make the top layer MDF because it rounds over so much better than plywood.





The good thing is that working under the sun makes the bondo and Duratex dry super fast which is good because I had to paint, sand, bondo, sand, paint, sand, bondo and repeat. Sun, FTW.

Wrapped the ports with Protecto Wrap to add some damping to the rather thin 2.5" ABS flared ports from PE. Protecto Wrap is good and dirt cheap and it works: http://tinyurl.com/p8z5k8u



I had a mini panic attack when I tried to push these ports in by hand......ended up using a hammer and beating them into submission. Got Gorilla glue all over my hands in the process....yay.



Ready for drivers.



Drivers installed and then I notice a major cosmetic flaw. The drivers are not centered perfectly!!!
I have no clue what happened but BOTH cabinets have the same error so at least I have symmetry.



Anyway, they are done for the show and the finish, while not perfect, is better than naked for sure. Shout out to Duratex for making life easy.









Inside for a quick test and all appears to be good. I listened to two songs.....next time these puppies will sing will be in Fort Wayne.

[kenny_k]

I didn't notice the speaker offset until you opened you BIG mouth. They look GREAT and my opinion counts! You da Man Bryan.

[mattsk8]

That's funny, I sat in front these for how long Friday night and into Saturday morning and never noticed it?! These sound amazing!!! Thanks for bringing them, was a great time!