Candidates for New DIY Build - Floorstanding for Music & HT

[JazzyG]

I got the holes cut for the Accuton midrange drivers now. These were easier, since there are no rabbets required for these drivers, they install in a plain round hole by use of an expanding clamp/O-ring assembly. This is a neat design as it allows you to place your tweeter super close to the tweeter, which can improve sound quality.

Next up...measuring and marking out the cuts and rabbets for the rectangular ribbon tweeters. This will be new territory for me and I have a new jig I put together to do the job...keep an eye on this thread for updates!

[JazzyG]

Presenting...my DIY adjustable square/rectangle router jig!!

[JazzyG]

I was able to use my new router jig to cut the tweeter holes and rabbets with precision. After cutting the holes, I went back and measured/marked for the rabbets and cut those, so the tweeters will sit flush on the baffle. I also went ahead and measured/marked and cut the hole on the rear panel for the binding post plate. I essentially have a flat pack for the speakers at this point. Still a lot of things to do, but moving on to different things other than baffle cuts now.

[Steve Lee]

Most impressive, JazzyG!

Excellent work and the photo's are awesome, too.

Thanks for posting.

[JazzyG]

I did the glue up for the 5 pieces, other than the baffle, this week. Have to admit, gluing up a larger floor stander is more challenging than a bookshelf speaker or bird house! I did learn some lessons on these two cabinets, luckily nothing bad enough to prevent the project from moving forward. I like to work very methodically and take my time, once the glue starts flying you are on the clock and sometimes simple things get overlooked or stuff just happens. Oh...and you can NEVER have too many clamps!

[scottvalentin]

Nice job with the router jig!!! Thanks for bringing us along with the pics.

[JazzyG]

A lot has happened since my last update, the glue up ended up being pretty good after some tedious sanding work, a little PC Woody putty, and a lot of patience. PC Woody is awesome stuff, but it does take awhile to cure, especially when it is cold like it is here this month, so at 55-65 degrees F ambient it can take days to do an application, cure, sand...and repeat. My shop is well insulated, but not heated, so I run a space heater during the day to keep it reasonably warm to work. At night I have been bringing the cabinets in the house to help with curing of the glue & putty. While I did get a good seal on all joints, I decided to go ahead and seal all the internal seams with some DAP black caulk, just as a precaution, to be certain I am 100% airtight on the seams. I use a trick to test the seams by shutting off all the lights in the shop and putting a bright flashlight in the cabinet, any seams that did not get a good seal will light up...like a Christmas tree...well not really more like the light coming from around the frame of a closed door. I also sealed the entire inside of the cabinet with a watered down solution of Titebond 3 to seal it all up and waterproof everything to help prevent any cracking due to environmental changes. When you water the glue down, it soaks into the MDF and is kind of like a sanding sealer.

[Steve Lee]

What is your recommended glue to water ratio mix for the "sanding sealer", Jazzy?

[JazzyG]

Steve--It is not a very scientific measurement, I just put some water in a yogurt cup and squirt in the glue until 'it feels right'. Don't put too much water in the cup to begin with, you don't want to have to use any more glue than necessary and you can always mix more. The thinner the mix, the more I think it soaks in, but thicker leaves a heavier coat. Shoot for something around 50:50 to start, that was the advise given to me when I asked about this trick on a woodworking forum that I belong to. I was working on a birdhouse at the time and wanted to seal the interior as I used plywood. That guy said he made a cardboard sign, sealed it with two coats of Titebond 2 @ 50:50, and put it out by his mailbox to test and that it is holding up well.

[Steve Lee]

Thanks!

That is at least a good starting point for me as I have 2 cabinet projects in need of this treatment awaiting my motivation.

[JazzyG]

This segment is on drilling pilot holes in the baffle for mounting the drivers. For this, I rested the baffle on the other half of the glued up cabinet, so that the drivers can be easily placed in the rabbets for marking the holes. I put each driver/port in the baffle, measured and marked, and then removed the driver and moved on to the next one. After I had them all marked, I set up my Shopsmith in drill press mode and set a depth stop so that the holes would only go as far as necessary and not accidentally drill all the way through the baffle. The Shopsmith was very helpful in making the holes accurate and straight, the fence helped limit movement whilst drilling the holes.

[JazzyG]

The cabinet is lined internally with acoustic foam, this section is where I made the cuts and adhered them to the cabinet. I used an OLFA RTY-3/G 60mm rotary cutting tool to make the cuts, it worked really good--super sharp. If it was any smaller it wouldn't have been able to cut all the way through foam, so get the large 60mm model if you get one. The foam has a sticky back, so you just peel the paper backing off and adhere it, the hot glue drops were added as per the directions, they did seem to really make it grab the wood. The instructions are very detailed in this kit, providing the exact dimensions to cut all the various pieces, so I just made all the cuts and then proceeded to install them in the cabinets later. I managed to get a few drops off hot glue on my fingers and it is pretty dang hot, but falls just short of a damaging burn...just barely.

[JazzyG]

I made the decision to put the veneer on the back and install the binding posts/plate before I put the baffle on...in hind site I don't think this was absolutely necessary. It did allow me easier access to all the wires and stuff for routing them and getting the binding posts wired up. The directions are really good in this kit, but they leave you to your own as far as deciding the order of operations, there is always more than one way to do everything involved in a build like this. After reviewing best practices on the 3M PSA veneer adhesive, they recommended a couple coats of urethane over the raw veneer before pressing on the veneer. Sounds easy enough, and it is, but 2 coats of urethane is a lot of prep, dry time, sanding, 2nd coat, dry time, etc. So, I went ahead and put urethane on the cabinet, minus the baffle which was not yet installed. This is where I could have saved a lot of time by waiting to do the veneer on the back, days of drying and I would end up having to go through all that again after the baffle was installed as it's edges needed the urethane too. After fussing with the crimp on connectors and quickly remembering how much I hate them, I made the decision to solder all the connections from the binding posts to the drivers, all using WBT silver solder. I like the solid connection of a solder joint, makes absolutely no sense to me to use crimp on connections and I have NEVER been able to get them to actually crimp on in an acceptable way. Someday, I might invest in a good crimp tool and some high quality crimp on connectors...but until then I am a solder man.

By the way, the Dayton Audio premium binding posts and black anodized terminal plate included in my kit look great and are well built!

[Steve Lee]

Looking really good there, Jazzy!

BTW - I have used these T&B crimpers for most of my early profession and still use them to this day while doing computerized building automation and speaker building - they are top notch and will last you a lifetime --> https://www.amazon.com/Thomas-Betts-...018LD2PU&psc=1


Great photo's, BTW!

Keep them coming!

:D

[JazzyG]

Steve--thanks for the tip on the T&B crimpers, I spent hours online trying to pick a really good pair and got frustrated and gave up. I put them on my shopping list and will pick them up next time I have some credit card rewards points to spend in my Amazon account. I just blew all my points buying some other tools! I do see the value in a good crimp tool setup. I have spent a lot of time doing really nice solder connections, with heat shrink and vinyl sheath, on things where a simple crimp would have been fine...non-audio stuff especially.

[Steve Lee]

Here is another tip for you when crimping your wire with Sta-Cons, Jazzy:

Make sure you orient the curved part of the crimping tool surface with the center of the open/joining portion of the crimp connector. (This action keeps the crimp from opening-up/splaying).

Look inside the barrel of the connector and rotate it so that you align these mating parts as suggested and you will have no further frustrations concerning either of them.

[JazzyG]

Next step...gluing on the baffles! For some reason, this feels like a really big step forward in the project, even though it did not take all that long to do it. It is always a bit stressful doing the glue ups though, but this one went really smooth. I knew I was going to have some slight alignment issues to sand/putty, but other than that it was perfect. These bar clamps from Rockler made it really easy, the jack stands enabled me to put the clamps on and spin the handles to tighten them. The important thing to do on these glue ups is to get a lot of glue in your joints, both sides, so you get squish when you tighten the clamps. Do not over tighten the clamps, just snug 'em down as too much pressure can cause warpage type issues and push too much glue out. You want good even pressure all around. I did them one at a time as you need every clamp in your arsenal for this!

[JazzyG]

The next step was to get the ports put together. The kit came with a long tube that needed to be cut into shorter pieces and attached to the inner/outer flanges using connecting rings and hot glue. Cutting the long tube was the tricky part, if you have ever cut a piece of PVC pipe and tried to get an exact length and smooth even edges then you know what I mean. I came up with an idea using the band saw on my Shopsmith! I clamped a board down as a 'fence' at the exact measurement I needed, then push the tube through the blade, rolling it through didn't work as well. Luckily, the kit came with plenty of tubing, so I was able to do better on my 3rd attempt. I used a sanding block for final truing of the length and to even everything up, I know port length is very important to the tuning of the bass...so measured it super close. I glued it all together using this black hot melt glue from PE and it worked awesome, was so glad to find it in black as it makes the port look so much better. I did wrap the outside joints with black electrical tape to ensure a tight seal, that part was not pictured.

[JazzyG]

After sanding and putty to get the baffles squared up with the rest of the cabinet, it was time for painting the baffles! I chose to use ExoHyde textured black paint which is available from Parts Express. I found the ExoHyde to be very easy to work with, it goes on nicely with minimal surface prep (sanding with coarser paper), dries fast, and is extremely durable from what I can tell. You can get some different effects using this paint, depending on how you apply it. I wanted to get a finer, lower crinkle, look so I let it dry slightly and then went over it again with the roller w/o adding more paint to it. This got an almost powder coated look, a bit coarser than that, but that kind of look. I started doing it indoors, the VOC content is pretty low, but decided to move it outside as it was a sunny day and my test board was drying much faster in the sun than my project was inside. The direct sunlight made a big difference as I was able to more easily see the results as I went and know that I wasn't missing any spots. I bought a gallon as it is a lot less expensive per quart, but most projects will probably only need the quart size. I will try to find some other uses for it though, I think it could be used in a lot of different woodworking applications. Overall, I am very pleased with how the baffles turned out!

[JazzyG]

Once the baffles and Urethane on the sides of the cabinets had fully cured, I moved on to the veneer. I used veneer with the 3M PSA glue backing as it is easy to work with and it sticks really well. It is important to press really hard on the veneer after application to ensure a good bond, I used the edge of a board I had slightly rounded with sand paper to apply pressure. It is easy to mess up an edge by pressing right where extra veneer extends over the edge, so watch for that if you use this stuff. I used my smaller Porter Cable - Model 100 router with a Freud edge trim bit, fitted with a bearing, to get a nice clean trim all the way round.

A couple of things I learned, the PSA glue will stick to your router bit and bearing, so I had to stop and clean it off after every couple cuts. I found that if I had a lot less excess to cut off, a few mm's vs. an inch, it was less of a problem. I left a bit too much extra, about 1" all the way around each piece, to be safe. However, that also means that the grain match going from left to top to right side doesn't flow all the way around, I only got grain match on 1 of the 2 transitions as I left just a bit too much extra to be safe. The reason you leave extra is that if you get started a bit off on one edge, by the time you get to the other edge you can run out of veneer and then you are pretty much SOL. A bit of a tradeoff on how accurate you think you can cut and adhere everything, get it as close as you can without leaving yourself short! The good news is, I had just enough to complete the project, hardly any waste, and the wood looks great even if you don't get full grain wrap.

[djg]

I use the PSA veneer a lot. More time spent cleaning the bit than anything else. I generally do about 1/2" extra, but I never did a tower like yours. One chance to get the veneer on straight.
Nice job

My PSA veneer jobs have lasted years, if you're worried about durability.