I just played devils advocate with the A.I. for a while. First, 0.6mm translates to 0.023622" so we are in the neighborhood =). A.I. seems to be pretty confident that the minimal 3.5% isopropanol per weight thinning ratio would be suffice... Even if thinning more, the degradation of strength results in a product thats still much stronger than PVA. Resin also is the clear choice as far as bonding performance to the fiberglass. Its hard to say that the choice is obvious. Self leveling is beneficial for the top coat. ArtResin was recommended for its resistance to yellowing but I I am wondering should I even care... For an adhesive for the Fabric tot he wood, yellowing doesn't matter much but what I was thinking is that if the epoxy is dyed black, yellowing won't be much of a factor. Dyed black, and with a thin coat, for the top coat, it should be something like a tint, which is what I really wanted.
The Fabric I bought is double biased, which means that on top you have the stitched pattern but underneath you would see the layer of chopped strand matt. These two layers are joined together somehow... You would think..... that this scenario is good for everything that I am trying to do. At this point my biggest worry is incorrect curing... From my research it seems its best to error on extra hardener instead of extra resin. Ideally things would be perfectly matched, but somehow things happen and I think a small calculated additional percentage of hardener is warranted
I have 6 gallons worth of resin/hardener bought back at the beginning of this project... It is yellowing but as I said, after is dyed black I don't think this issue will matter. Thanks for the convo!
Here, have a laugh
The Fabric I bought is double biased, which means that on top you have the stitched pattern but underneath you would see the layer of chopped strand matt. These two layers are joined together somehow... You would think..... that this scenario is good for everything that I am trying to do. At this point my biggest worry is incorrect curing... From my research it seems its best to error on extra hardener instead of extra resin. Ideally things would be perfectly matched, but somehow things happen and I think a small calculated additional percentage of hardener is warranted
I have 6 gallons worth of resin/hardener bought back at the beginning of this project... It is yellowing but as I said, after is dyed black I don't think this issue will matter. Thanks for the convo!
Here, have a laugh
You have 6 gallons of "extra" resin 😵 . I always try a small test batch of resin before actually applying it to check the ratios and working time for the conditions.
I would do something to strengthen the kerf slots. You have 2 large woofers coupled by a remaining thin sheet with thin plywood ribs attached. I would not use water based products in the slots because of swelling concerns. You're probably OK with a heavy epoxy fill and fiberglass over top. A chopped mat underside of the cloth will keep the cloth "pattern" straight, otherwise it can wander and look wonky.
I would do something to strengthen the kerf slots. You have 2 large woofers coupled by a remaining thin sheet with thin plywood ribs attached. I would not use water based products in the slots because of swelling concerns. You're probably OK with a heavy epoxy fill and fiberglass over top. A chopped mat underside of the cloth will keep the cloth "pattern" straight, otherwise it can wander and look wonky.
The kerf voids are reduction of wood thickness in the highest pressure area in the entire box, and an invitation to buzzing as the small sections start to delaminate.
Using BondoGlass, TigerHair or any of the fiberglass reinforced polyester fillers would be a relatively fast permanent solution to the problem created by the kerfs.
From my experience with using fiber mat and resin (epoxy or poly) I'd say fiberglass reinforced polyester filler would be at least twice as fast, have better finished appearance, and far easier with less mess than laying up mat.
Art
I don't know how much difference it will make but the CSA through the circle separating the front and rear chamber should be that of slot loading the front of the woofers. Sounded like a good idea but probably won't matter. All bracing spaced according to matrix bracing recipe adjusted for 3/4" wood and a little over kill. The coolest thing is eveything for the most part is repurposed wood from the first 15" enclosure. I only had to buy wood for the woofer baffles.
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