A corse brushed vertical finish would look stunning and easy enough to apply. Even anodizing after that would be over the top, plus help to protect it due to the surface hardening. Use to make our faceplates and panels this way. Mostly made from SS, engraved, corse sharpening stone and some cutting oil for the finish and enameled lettering. Al only requires anodizing to give it a tough finish.
I'd say well worth the effort you have put into them.
I'd say well worth the effort you have put into them.
Time for another update... waiting for a coat of epoxy to dry...
Well, where to start! After the success with the baffles it was time to fix the enclosures. Taking in mind all the advice I got here I had to make up my mind.
Most of the advice pointed out to get rid of the threaded rods, dedicated to save the nice wood finish I had achieved.
But the wood finish was a stray of my original plans. I just had to try it because the wooden stacks looked so good! But sadly it didn't work out so I went back to my original plan. That plan was epoxy plus a fibre glass weave mat. After thinking it trough a bit I figured the wooden stacks are always going to shrink and expand. That will continue to put a lot of pressure on the epoxy/mat laminate. About halfway in the story about the dreaded cracks I came to the conclusion if you want to build a stack this high, you've got to include a level of elasticity in that stack.
So the arrays went back in the garage and I immediately sanded down the finish to bare wood. That hurt! So I figured I should do it and be over with that.
After that I picked up a saw and started hacking up the enclosures in pieces(!)
Starting at the backside with a hand saw and a jig saw I cut 24 times, leaving the bottom one in tact.
Between the rods I drilled a few holes to fit the jig saw and cut the sides. The front was easy again with the jig saw.
I made sure to get about a 1.5 to 2mm cut all around. After that awful job I bolted on the baffle.
Some rings and nuts as spacers and in the speaker chambers I fit pieces of ply with the right dimension to keep about equal distance with the baffle to keep the enclosure straight.
I decided to seal the cut in the inner chamber with the same rubber glue I used to seal the rods in the stack. Then from the outside I poured in some DIY PU foam (water tight foam, 2 components, used in ships). The home brew foam is a bit different from the spray cans in the hardware stores. It is a closed cell foam.
I did the back and the sides, next unbolt the baffle to do the front.
After that step, bolt on the baffle again and hang the enclosure for epoxy work.
With some left over scraps I build a rig to hold the enclosure...
(like a turkey above a fire
)
Well, where to start! After the success with the baffles it was time to fix the enclosures. Taking in mind all the advice I got here I had to make up my mind.
Most of the advice pointed out to get rid of the threaded rods, dedicated to save the nice wood finish I had achieved.
But the wood finish was a stray of my original plans. I just had to try it because the wooden stacks looked so good! But sadly it didn't work out so I went back to my original plan. That plan was epoxy plus a fibre glass weave mat. After thinking it trough a bit I figured the wooden stacks are always going to shrink and expand. That will continue to put a lot of pressure on the epoxy/mat laminate. About halfway in the story about the dreaded cracks I came to the conclusion if you want to build a stack this high, you've got to include a level of elasticity in that stack.
So the arrays went back in the garage and I immediately sanded down the finish to bare wood. That hurt! So I figured I should do it and be over with that.
After that I picked up a saw and started hacking up the enclosures in pieces(!)
Starting at the backside with a hand saw and a jig saw I cut 24 times, leaving the bottom one in tact.
Between the rods I drilled a few holes to fit the jig saw and cut the sides. The front was easy again with the jig saw.
I made sure to get about a 1.5 to 2mm cut all around. After that awful job I bolted on the baffle.
Some rings and nuts as spacers and in the speaker chambers I fit pieces of ply with the right dimension to keep about equal distance with the baffle to keep the enclosure straight.
I decided to seal the cut in the inner chamber with the same rubber glue I used to seal the rods in the stack. Then from the outside I poured in some DIY PU foam (water tight foam, 2 components, used in ships). The home brew foam is a bit different from the spray cans in the hardware stores. It is a closed cell foam.
I did the back and the sides, next unbolt the baffle to do the front.
After that step, bolt on the baffle again and hang the enclosure for epoxy work.
With some left over scraps I build a rig to hold the enclosure...
(like a turkey above a fire
)
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Nice work sorry you had to cut it. You made 25 segment for expansion joints but I think you may have been able to get away with 5 segments for expansion. Was there a reason you did so many sections? Great ideas to use the expanding
foam though. Sheets of EVA foam cut to the outline may have worked too.
Great progress!
foam though. Sheets of EVA foam cut to the outline may have worked too.
Great progress!
Having the enclosure in the rig it was time for epoxy. First soak the wood with epoxy for a better laminate bond with the cloth.
Working wet in wet I applied the cloth when the epoxy was still wet enough to leave a finger print.
Then worked in the epoxy in the mat. Applied in a coat from the top down, and squeezing it out with a bondo spreader...
The cloth was cut oversized and I taped it at the bottom to the baffle (which had tape on it to protect it from the epoxy).
Took my time with the spreader to really squeeze the epoxy into the mat. Due to the weight of the overhang cloth I was afraid the cloth would separate from the enclosure at the baffle edge. I chickened out and after letting the epoxy gel a bit first I taped the entire enclosure with some household plastic wrap.
Didn't have enough time to tidy up this part of the job, so it left me a few wrinkles in the first layer. But at least it put pressure on the mat to let it cure to the edges.
I stayed away from the garage the next day to prevent me from doing something foolish. It is after all my first time working with epoxy. This kind of thing is new to me.
I did rip off the plastic wrap after 24 hours of dry time and it looked promising.
The day after that, with at least 36 hours dry time I sanded the laminate, cut the overhang and took out the baffle and spacers from the chambers.
Not bad for the first try...
Next it was tile to fill in the mat with epoxy so I mixed up a batch of epoxy with micro balloons. Being the first time I had my mix wrong to I followed with a second coat wet in wet that evening. No pictures of that but it looked awful. I used a roller to spread it out and the thing was shedding off fluff(?) into the exterior. But it needed sanding anyway so with a finer grid sand paper on my random orbital sander it looked like this:
Starting to look half decent...
I figured one more coat with micro balloons but something different to spread it out. I had already tried the spreaders for that job and didn't like it. I figured I wanted a "Duratex" like finish so I took a gamble and used 2K lacker rollers with the chance of it dissolving or burning up from the epoxy. Lucky for me it didn't. It left me with a very nice Duratex like finish. I think I'm going to keep it like that.
It was time for this enclosure to come of the rack anyway as the next one was ready for more of the same. That's where I am today:
The somewhat rough finish will get 2 coats of 2K PU in satin black but I can't sand it down. I want to keep that texture.
A piano black finish was never in the cards and not wanted. The enclosure would have to be perfect for that to work. I'm running out of time due to it being fall and still have to finish the second one. But I don't want that kind of smooth finish anyway. For now I'll keep the aluminium blank. Still have to make the outer baffles but needed to finish this first. I'll polish them as I did the stands, they held up pretty good over a years period.
Still far from ready but getting there. Hopefully more to come soon!
Working wet in wet I applied the cloth when the epoxy was still wet enough to leave a finger print.
Then worked in the epoxy in the mat. Applied in a coat from the top down, and squeezing it out with a bondo spreader...
The cloth was cut oversized and I taped it at the bottom to the baffle (which had tape on it to protect it from the epoxy).
Took my time with the spreader to really squeeze the epoxy into the mat. Due to the weight of the overhang cloth I was afraid the cloth would separate from the enclosure at the baffle edge. I chickened out and after letting the epoxy gel a bit first I taped the entire enclosure with some household plastic wrap.
Didn't have enough time to tidy up this part of the job, so it left me a few wrinkles in the first layer. But at least it put pressure on the mat to let it cure to the edges.
I stayed away from the garage the next day to prevent me from doing something foolish. It is after all my first time working with epoxy. This kind of thing is new to me
.I did rip off the plastic wrap after 24 hours of dry time and it looked promising.
The day after that, with at least 36 hours dry time I sanded the laminate, cut the overhang and took out the baffle and spacers from the chambers.
Not bad for the first try...
Next it was tile to fill in the mat with epoxy so I mixed up a batch of epoxy with micro balloons. Being the first time I had my mix wrong to I followed with a second coat wet in wet that evening. No pictures of that but it looked awful. I used a roller to spread it out and the thing was shedding off fluff(?) into the exterior. But it needed sanding anyway so with a finer grid sand paper on my random orbital sander it looked like this:
Starting to look half decent...
I figured one more coat with micro balloons but something different to spread it out. I had already tried the spreaders for that job and didn't like it. I figured I wanted a "Duratex" like finish so I took a gamble and used 2K lacker rollers with the chance of it dissolving or burning up from the epoxy. Lucky for me it didn't. It left me with a very nice Duratex like finish. I think I'm going to keep it like that.
It was time for this enclosure to come of the rack anyway as the next one was ready for more of the same. That's where I am today:
The somewhat rough finish will get 2 coats of 2K PU in satin black but I can't sand it down. I want to keep that texture.
A piano black finish was never in the cards and not wanted. The enclosure would have to be perfect for that to work. I'm running out of time due to it being fall and still have to finish the second one. But I don't want that kind of smooth finish anyway. For now I'll keep the aluminium blank. Still have to make the outer baffles but needed to finish this first. I'll polish them as I did the stands, they held up pretty good over a years period.
Still far from ready but getting there. Hopefully more to come soon!
Well, the 24 cuts make sure the stress is kept to a minimum. The steel rods and epoxy laminate hold the (now) small stacks in place. This way I could also line up the bolt holes with the baffle.
On a further note, the expansion rate of glass fibre and aluminium are close to the same. So hopefully this will have me covered (pun intended) with the seasonal changes. I'll be off to the garage in less than an hour to put on the cloth on the second one.
Jaimo: thanks for the nice words. I'll never give up (maybe that's a defect of me).
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Here's a close up of the finish, don't mind the inner side of the enclosure. The inside still needs a bit of work and will get a coat of epoxy in white. Still some sealing to do as well.
I wanted to sand this coat down and do a finer texture but it is nice and even. So why mess it up. It's close in appearance to Duratex (not quite but close enough).
It's almost a shame I have to paint it for UV protection.
I wanted to sand this coat down and do a finer texture but it is nice and even. So why mess it up. It's close in appearance to Duratex (not quite but close enough).
It's almost a shame I have to paint it for UV protection.
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That finish looks great as is. Reminds me of rough hewn black granite. If you are using black epoxy, I assume the pigment was carbon black and that should block uv. Maybe you don't need to paint? Great work - looks very cool. The foam in between the segments gives you axial constrained layer damping. May reduce harmonic distortion and cabinet induced resonances in any case.