Fibreglass mess

[colterphoto1]

Well I had this really old pair of beat up Heresies, H700's to be exact that I got from DrWho.

Wanted to make 'outdoor' pseudo-industrial models of them. Thought it was a great idea, then came the fibreglass.

What I intended to do was make some in the old 'rock and roll' case style, with the glass cloth and 4" wrapping all edges, so corners were like 3 layers thick. Industrial handles up top, new jacks, revamp xovers and put stand mount on the bottom.

I'd seen many of these 'gel coated' rock and roll road cases over the years and knew that although somewhat messy, it was possible to do.

So I went to boat shop, got flat cloth, 4" roll glass, and quart of poly resin with hardener.

I used table saw to rip off the grill lip, so the front edge would be square, used 1/2 round over bit on all edges, wood filler on all cracks and bolt holes, rough sanded the whole thing with 60 grit and used lacquer thinner to strip off any old oil and wax so the glass would adhere.

Boat guy said to cut the flat pieces with the cabinets dry, place one on a side, then pour the resin on and squeege until it pushed through and the cloth was no longer 'white'.

Two problems.

First batch, being a small batch (2 sides and 2 tops) I put in too much hardener and it got chunky while working with it. I scraped away most of excess, but now have rough texture I'll have to sand down.

Second batch, maybe not enough hardener, it's still a bit sticky 12 hours later (it's humid outside though).

This is tougher than it looks, both in terms of mixing the resin in small batches, keeping the cloth in place during squeegee, and that you have to sand each coat and rough it up before next layer can be applied.

Surely theres a better way, wish I'd just painted them black now....

Any help?

Michael

[DrWho]

I saw you posting and was wondering how things were coming along....I don't have the faintest clue about fibreglass so can't help you out. I'm sure they will look great once you do figure it out and get them finished. Will you be doing the metal trim too? I remember you mentioned rounding out the corners so perhaps I've got the wrong vision in my head. Is this a sheet a fibreglass being added to the sides? Or is this some sort of goopy mixture being applied to the wood to turn it into fibreglass goodness?

[colterphoto1]

it's a sheet of fibreglass mesh applied with goop to each side, top and bottom. Then the idea is to use a 4" roll of material and go over each edge (so 2" on each side of edge), they all overlap on the corners, so they get built up like 3 layers deep.

Boat guy said that poly resin wouldn't take the colorant (although can says it can), so I'm just putting it on clear, then will paint oil base black over it.

The idea is to make em easy to dust, water resistent, etc. I'm putting a metal grill on the backside of motor board like HIP's.

Michael

[Xover]

Ahhhh but the aroma-therapy is heavenly.

Obviously you need an itch to scratch.

Enjoy!

[Daddy Dee]

Michael,

That process does sound more difficult than one would imagine at first. I'm no help there. But hope that works out to your satisfaction. What you are envisioning is a pretty cool outcome.

[Def Leper]

I've done a lot of 'glass work in my time, and your first mistake was getting only a quart of resin. You might be able to get away with a gallon for two speakers, but five quarts will be closer.

As you've already discovered, the key is to mix the proper amount of hardener, mix it thoroughly and quickly, and avoid injecting air into the resin.

Your boat guy doesn't seem to have done fiberglass work before and gave you bad advice. Brush out a fairly generous layer of resin first and then lay the cloth on top, press in well, and then brush in more resin to saturate the cloth. Get a $10 hot air hair dryer to hit the resin with very hot air to drive out the bubbles. (A propane torch works well too, just don't hold the flame on the resin too long.) If you squeegee resin over dry cloth, you'll never get the air out. What you then end up with is a leaky surface that will wick water into the voids between the cloth and cabinet, causing wood swelling, rot, and failure of the plywood plies.

Don't forget to watch your working time. The resin also likes to flow out and it's pretty easy to end up gluing your project to your work surface if you aren't careful.

[Doc Robin]

I have used wax paper to keep the project from getting stuck to the table. also used it on top of the glass and resin to help work the glass into the resin, not much of a mess, it just peels off.

But I would do a test sample before it trying on the speakers to make sure. Bill