Fiberglass Help/Hood Mod

[munki63]

Im thinking about chopping my stock hood, ive read a few threads including this one http://www.x-h2o.com/threads/64316 I have a few questions

- How many layers of epoxy resin + fiberglass do I need where its strong enough

- should i use fiberglass matting or fiberglass cloth

An Idea ive had too get the hood lighter is too cut the fire extinguisher nook out and just glass straight accross and chop it like the above thread

Also any pointers you guys have for fiberglass technique i NEED THEM ALL

Thanks
-

 

[INDebtSJ]

I cut the fire extinguisher out along with the top ff course. I left the oem liner in so I could fill it with great stuff.
Then I shaped it until I thought it looked good and symetrical. Layed duct tape down and then glassed over the top with some very thin fiberglass to hold that shape.
I then cut the liner out and glassed from the inside.
I put alot of fiberglas on mine, but it was my first time ever doing something like this.

Good thing about the great stuff is that you can keep adding and subtracting untill you like it.

Hope this helps.
Scott

 

[munki63]

That's a good idea, so after you put a layer on the top you removed the liner and took the great stuff out with the duck tape? What type of fiberglass did you use

 

[ksarge91]

I like the foaming idea. That way you can really shape it to your liking

-With mine I ripped the liner out first
-installed the nosepiece to see where the lines would need to be
-masked it off, and cut it.
-the I layed a piece of cardboard over the each hole from the outside and duct taped the cardboard to the hood tight. (wrap the cardboard in duct tape to avoid it sticking to the glass when you pull it up)
-Glassed from the inside with, I think 2? layers of 12oz
-Once that cured I pulled the carboard off and used filler to make the hood flush.


For the pole rest area I did the same. I didn't cut out teh fire extinguisher area, but can't store the extinguisher there anyway due to the deeper pole channel.

All in all it wasn't hard at all, just a little time-consuming. Mine seems to be pretty strong the tops where it's all new material are stronger than the original material and it weighs in a 14.1, I'm not sure exactly how much a stock one weighs though. Use epoxy resin for everything. Poly won't bond

 

[INDebtSJ]

That's a good idea, so after you put a layer on the top you removed the liner and took the great stuff out with the duck tape? What type of fiberglass did you use

The duct tape kept the foam from sticking to the fiberglass.
I used what I had left over from reinforcing the hull. 1708 I think.
Came out alittle heavey but its solid.
After I finished the outside I then did a new liner.

 

[INDebtSJ]

I like the foaming idea. That way you can really shape it to your liking

-With mine I ripped the liner out first
-installed the nosepiece to see where the lines would need to be
-masked it off, and cut it.
-the I layed a piece of cardboard over the each hole from the outside and duct taped the cardboard to the hood tight. (wrap the cardboard in duct tape to avoid it sticking to the glass when you pull it up)
-Glassed from the inside with, I think 2? layers of 12oz
-Once that cured I pulled the carboard off and used filler to make the hood flush.


For the pole rest area I did the same. I didn't cut out teh fire extinguisher area, but can't store the extinguisher there anyway due to the deeper pole channel.

All in all it wasn't hard at all, just a little time-consuming. Mine seems to be pretty strong the tops where it's all new material are stronger than the original material. Use epoxy resin for everything. Poly won't bond

I did the same as far as lining it all up with the nose piece. I would put the hood on with the pole until I liked the way the pole sat in the hood. It took some time but it was winter.
I would post pics from my album,but Im not sure how.

 

[munki63]

12 oz epoxy resin? What's stronger glass matting or the sheets?

 

[INDebtSJ]

Epoxy resin with 12 oz glass.

 

[stanton]

12 oz epoxy resin? What's stronger glass matting or the sheets?

i would do 2 layers of heavy nytex, its got a layer of mat and 2 layers of cloth in one. the mat is for adhesion, the cloth is for strength.
u guys are gnar bty.

 

[Dustin Mustangs]

^I'm with him^. The best way to go is with both mat and cloth. Really the only right way to do that with epoxy resin is with the biaxial offerings like us composites offer. Use 12 oz if you have alot of tight curves or 17 oz if your part is a flatter shape.

 

[munki63]

I'm good at wrenching but not glassing, so once I clean everything I put the resin on then the matting then resin then wait till it's hard then I do my next layer ect?

 

[ksarge91]

I'm good at wrenching but not glassing, so once I clean everything I put the resin on then the matting then resin then wait till it's hard then I do my next layer ect?

I do a couple brush strokes of resin on the surface just to hold the glass in place, then I lay the glass and apply more resin ontop with a dabbing motion of the brush until the glass is wet. You want to wet it, not drown it. Then I use a squeegee on the flat surfaces to get any excess resin out. Add the second layer of glass before the first one cures.

 

[munki63]

So do you want too do all your glassing before it cures? Weather it's 2 or 3 layers?

 

[chad]

yes

 

[Dustin Mustangs]

Yes. That way you get a chemical bond between the layers and not just adhesive (like it would be if you let them cure in between). If your part needs to be really thick you'd have build it up over a couple of cures so it doesn't get to hot when it kicks.

Rough up the mating surface with sandpaper and make sure to remove all paint or other surface coating while you are doing this. Vacuum out all the dust then clean with a strong solvent like acetone. Measure your resin and hardener very carefully, getting the ratio perfect is very important. You also need to make sure they are very thoroughly mixed together. Most suggest mixing in one cup for a while and then pouring into a new cup and mixing some more. Have everything cleaned and your glass cut and ready to go before you mix. Paint the contact area with resin. I personally wet out my glass on a flattened out garbage bag and then apply it. Regardless of how you do it, make sure it is fully wetted. You can tell it is when it turns from opaque to clear. You also want to get as much resin out as you can while keeping it clear. When laying it up look for bubbles which will look white similar to an area that isn't wet enough. Get them out any way you can before adding another layer. Temperature is import during the cure. Don't so this in a 30` garage unless your resin is made for it...

 

[ksarge91]

So do you want too do all your glassing before it cures? Weather it's 2 or 3 layers?

Yes. Lay all the glass, then squeegee the excess resin and air bubbles out.

EDIT: They beat me to it, haha

 

[chad]

Yes. That way you get a chemical bond between the layers and not just adhesive (like it would be if you let them cure in between). If your part needs to be really thick you'd have build it up over a couple of cures so it doesn't get to hot when it kicks.

Rough up the mating surface with sandpaper and make sure to remove all paint or other surface coating while you are doing this. Vacuum out all the dust then clean with a strong solvent like acetone. Measure your resin and hardener very carefully, getting the ratio perfect is very important. You also need to make sure they are very thoroughly mixed together. Most suggest mixing in one cup for a while and then pouring into a new cup and mixing some more. Have everything cleaned and your glass cut and ready to go before you mix. Paint the contact area with resin. I personally wet out my glass on a flattened out garbage bag and then apply it. Regardless of how you do it, make sure it is fully wetted. You can tell it is when it turns from opaque to clear. You also want to get as much resin out as you can while keeping it clear. When laying it up look for bubbles which will look white similar to an area that isn't wet enough. Get them out any way you can before adding another layer. Temperature is import during the cure. Don't so this in a 30` garage unless your resin is made for it...

Good instructions...

I use a piece of aluminum foil taped to a flat surface in stead of the garbage bag though.

 

[Dustin Mustangs]

Another thing too, as you design this (or anything for that matter) remember that curved surfaces are much stronger than flat. You might be tempted to make something like this perfectly flat because it's easier to form a mold that's flat. If strength is a concern, make it slightly convex or concave and it will be a stronger part. You can also make troughs or ridges through an otherwise flat part and achieve a similar effect. Just something to think about...

 

[munki63]

Is it possable too make a nose piece?

 

[ksarge91]

Is it possable too make a nose piece?

Yes. Shape one with foam and glass over it. Once it's cured, seperate it from the foam, trim it to fit, and sand it.