SEOS Surround Build - Page 3

Those are a little small given the box is around 19" tall and 14.5" wide.

I got some 24" quick grip clamps: http://www.lowes.com/pd_122229-281-2021424N_4294936478__?productId=1205993&Ntt=clamps

A bit pricey (got those on sale and also borrowed another 24" set), but are quick and easy.

Bondo Hell

I forgot how much I hate this phase.

I'm sure there is a better way to do this, but I use bondo filler to create an even seem around the box. One step I should have done was to sand down the mdf before I started bond. In many cases, with the tight fit of the flat packs, I could have created a pretty even seem with sanding the mdf, with minimal bondo. But I didn't realize that until later.

Experienced finishers please weigh in, but from my noob adventures in my first build, I found that bondo works better than wood filler. Mainly it seems to lay down better and has less pits and holes in it. I'm sure I did something wrong, but I found with plain wood filler, as I sanded down the filler, I got pits/holes in the final layer and had to lay another layer. I got some of that with bondo, but much less.

As far as bondo, yes, this is the stuff used on cars. From what I read it works great with MDF. A word of warning is to play around with how much hardener to use and use smaller amounts of filler. If you use the "recommended" amount, it will dry very fast. If you are good with this stuff, that's fine. You can sand it in 30 min. But, if you are noob like me, that gets tough to get the filler spread out right, so I dialed back the hardener a bit. Takes longer to dry, but it easier to work with.

Once the bondo drys, use a rough grit to knock down the first layers and then when you are down to level (can't feel the filler edge) shift to finer grit. At least for me, even with a half sheet orbital sander, it takes me a long time to sand it down. And it takes a couple of times (filler/sanding) to get it right.

Bondo


Bondo Phase. This is the second round of filler. You can see I already sanded down one layer and laid the next layer down.


Post Sanding. This is the bottom of the box. This one is pretty smooth.


Minor Fix. This is the other bottom that has a small pit that needs to be filled.

Edited by Java - 11/22/12 at 12:44pm

Nearing the end...

I'm just going with flat black like the fronts. I would say I want to have them "blend in" to the side walls, but at 19" x 14.5" these are not going to blend easy.

Priming Done

All done with the priming phase. BTW, I decided that a video is pretty much useless for this phase since it doesn't really show you much versus photo's.

The key to this phase is sanding between coats. I used a rattle can primer and it still left a rough texture. Hand sand the surface until smooth. This also lets you fix and paint rolls.

Primer Used.


Before primer. All sanded down.


1st Coat of Primer


Some Issues. Don't know if you can see this, but there are some pits in some of the bondo.


Solution. I found this thread and it turned me to using glazing. It's found at a auto parts shop.


Glazing. Here's the glazing before sanding. It was thicker than I expected and started drying pretty quick, but worked out ok.


Sanded. It sanded very easy compared to the base bondo.


Final Primer Coat. A storm started blowing in so I rushed this a bit...

Edited by Java - 11/23/12 at 2:59pm

Thanks. From what I read in that thread I found, you still need a base of "regular" bondo.

Crossover Check



I jumped the gun a bit from a posting perspective. I shot the crossover build video, but its a super long bore-fest, so I got some editing ahead of me...

I wanted to post this crossover check video to see you all opinions. The first board seems to check out OK. It reads around 4 ohms. Seems a bit low. My mains showed about 6 ohms. Tux?

On the second board, I had two failure points. One the LF board, I had a bad capacitor. Note to self and all, double check all the components you get from PE as soon as you get the. Too late for a return for me.

On the HF board, it looks like I had a bad solder joint on the first inductor. Kind of strange though, since I twisted all of the leads. Solder is more of a glue than a conductor in my case.

Thoughts?

Edit: I updated the above youtube video with a corrected goof on board one (swapped in/out) and the fix on board two.
Edited by Java - 11/25/12 at 5:06pm

Rosin core from Rat Shack.

Are you saying it should be higher than 8 ohms? My main build with the 2512 (8 ohms) all came in around 6 ohms. I assume that it's because of the addition of the CD (in parallel?) the total speaker resistance falls to 4 ohms and then the crossover resistance adds some back. Make sense?

Did you check your boards resistance?

Thanks

Then I would starve...

Thanks, Tux. I warned you that I was still a noob at this.

The 6.4 ohms sound spot on for my mains. If memory serves, I was hitting around 6.3 on those.

Eagle eyed Tux found my goof. I reversed the "in and out" on the HF board for the test. Per below, now that I fixed my dumb a** mistake, the resistance is spot on at 6.4 ohms. The boards are fine, but but I goofed on the test set up...

Fixed & Tested



I fixed the bad solder joint on board two and even without replacing the "bad" capacitor, the board "passed". Right at about 6.5 ohms.

I'm thinking my "testing" just the capacitor may be flawed. You can test a resistor, but is resistance a good test of a capacitor? There's a gated thing going on, rights.

Anyway, all is good on the crossover front. I updated the video with these fixes and also replace the test on board one with the "right" test.

I'm also going to replace the earlier post with this update video and delete the old one from youtube so there is no confusion.