Fiberglass help please

chimp koose · August 14, 2009, 07:31:05 PM

I am now mounting the hood on my anglia. The problem is that the cowl and grill ends have changed shape . the cowl end has curled in and the grille end has flattened out. I think they were pulled from the molds too soon.I have had success straightening some other parts with a heat gun ,pressure and then cooling with water but this part does not want to cooperate . Any suggestions short of cutting it up?

C9 · August 15, 2009, 08:43:45 AM

It may have been incorrectly stored.

Try pulling it into the proper shape and let it sit for a few months.

If you can't do that, you may be able to get it mounted while holding it down with a ratchet strap or similar.

It should take a set and stay there after a while.

enjenjo · August 15, 2009, 11:43:02 AM

I think Jay is probably right. If fiberglass is not stored correctly before installing it can warp from it's own weight.

Now, how to fix it. It will take some time. You need to get the ends back into shape, which will be difficult to do on the car, because of springback. so you need to make a pattern of the ends off of the shape of the car, and modify the pattern to account for spring back. Make a jig out of plywood or MDF board that is the shape of the modified pattern. Make the jig so it just covers the edges of the hood. Clamp the hood to the jig so it conforms to the shape. Then if you have lots of time, set it in the sun on a hot day, or put some heat lamps on it. don't get it too hot though. Then let it cool. Do this several times to make it take a new set.

Once you have done that, get some light glass cloth, sand the inside, and glass the cloth on the inside of the hood, just a thin layer. This will help it hold the new shape.

chimp koose · August 15, 2009, 12:17:29 PM

Thanks guys for the advice.I made some 'end jigs' out of plywood quite a while ago ,I will have to find them. I think I stored the hood wrong. I have a radiant heater in my shop and the end of the hood that was closer to it is the worst. Enjenjo,if I clamp the front of the hood to the grill properly, it takes the right shape.Will a couple of layers of glass be enough to hold its shape? I thought I would have to build a substantial wood/metal bracing which I would like to avoid if possible.Also ,I can probably duct tape the back of the hood on to the car and get the right shape . If a layer or two of glass will hold its shape I may be able to do it without removing the engine for access. If I have to build bracing I would have to climb into an empty engine bay to get proper access to the back of the hood.Lastly, how close is close enough for the shape? I will likely need to use some sort of a filler material(product preferences please anyone)to get it just right.How much build up is an acceptable amount?Thanks again for your responses.

enjenjo · August 15, 2009, 12:37:19 PM

It can probably be done on the car, but off the car would be much easier. As long as it doesn't interfere with the fit, you can use as many layers as you want. And it gets heavy fast.

nzsimon · August 15, 2009, 08:05:36 PM

The beauty of glass is it is a cut and paste material

If heating and clamping doesn't net the result you want run a narrow cut here and there get it where you want it and reglass

chimp koose · August 16, 2009, 01:10:14 AM

nzsimon, that was something I was thinking about to repair the really bad area at the cowl.It is not moving near enough with heat.It is good to know from others that I am on the right track.When I have the hood fitting well I will mount hood hinges to the firewall and then figure out a way to attach the hinges to the hood. I am going to use chevy sprint hinges that have a horizontally flat mounting surface.I am not sure if I should make up the space between hinge and hood with wood or metal glassed into place. I am leaning more towards using metal,anyone with an opinion? I think I would have more hood adjustment using slotted holes and square nuts in the metal than I could with the wood. Does either stay bonded to the glass better? Thanks again guys for the input.

nzsimon · August 16, 2009, 02:54:32 AM

you can use whatever works but you will see whatever you bond to the underside side of the hood on the other as glass transfers the stresses no matter how much you block sand as that area will be a different thickness

You could make some braces that go from one side of the hood to the other and bond them to the sides of the hood done low where there is a swage that would hide any pulling then mount the hinges to the braces leave an air gap between the braces and the top of the hood
I have hinged mine on the sides for this reason
Or you could double skin it with the hood mounting points on the inner skinn boned along the edge like a factory piece that is how my boot is done

chimp koose · August 16, 2009, 12:47:03 PM

nzsimon ,thanks for the tip .I did not know that the stress would show through the other side.I think an inner skin would be the best as it would look more 'finished'. there is a horizontal flange along most of the sides of the hood that is about 1" wide.I could bond an inner to that .More work,but probably worth it.

papastoyss · August 17, 2009, 01:53:11 PM

Quote from: "chimp koose"Thanks guys for the advice.I made some 'end jigs' out of plywood quite a while ago ,I will have to find them. I think I stored the hood wrong. I have a radiant heater in my shop and the end of the hood that was closer to it is the worst. Enjenjo,if I clamp the front of the hood to the grill properly, it takes the right shape.Will a couple of layers of glass be enough to hold its shape? I thought I would have to build a substantial wood/metal bracing which I would like to avoid if possible.Also ,I can probably duct tape the back of the hood on to the car and get the right shape . If a layer or two of glass will hold its shape I may be able to do it without removing the engine for access. If I have to build bracing I would have to climb into an empty engine bay to get proper access to the back of the hood.Lastly, how close is close enough for the shape? I will likely need to use some sort of a filler material(product preferences please anyone)to get it just right.How much build up is an acceptable amount?Thanks again for your responses.

There is a product called Vette bond panel adhesive (made by Duro I think) that is an excellent product for repairing & filling fiberglas. I had a similar problem w/ a 37 Ford hood side & wound up clamping it to a 2x4 & relieve grinding the back side & reglassing it to get it straight. I used the Vette bond to fill the rough surface of the glas.

chimp koose · August 19, 2009, 02:19:13 AM

I found the alignment fixtures I made about a year ago . I have tried heat while clamping in the fixture to no avail. I will have to start grooving the underside and reglassing. I think I will look up the vettebond stuff,I will have to reshape and repair some of my attempted 'fixes'.I am off on another project right now however.Thanks for the tip papastoys!

papastoyss · August 19, 2009, 09:04:24 AM

Quote from: "chimp koose"I found the alignment fixtures I made about a year ago . I have tried heat while clamping in the fixture to no avail. I will have to start grooving the underside and reglassing. I think I will look up the vettebond stuff,I will have to reshape and repair some of my attempted 'fixes'.I am off on another project right now however.Thanks for the tip papastoys!

Glad I could help someone else for a change. Once again THANKS to all who have helped me in the past.