What do you recommend for repair of Fiberglass Hood Scoop Repair

[56_Kruiser]

I am in process of restoring this car:



I don't know how that hood scoop (or whatever it is called) is attached to the hood. But it is cracking. The picture below isn't the best picture, but you can see the crack:



Under the hood looks like this (lot of dust in the air when pic taken):



So, my question is how do you recommend I repair this for a lasting repair. (Actually, I'm a bit doubtful that a fiberglass attachment to the hood can be a 'lasting' beautiful finish).

A friend of mine recommended that I sand out what is likely putty that was used to finishe it off, and use canned fiberglass for most of it, with thin layer of putty to finish that off.

What do you think?

 

[TAZ]

Attaching a fiberglass scoop to a metal hood normally does crack. Especially one like that one, were that is the stress point.
The hood vibrates which doesn't help matters either.
The best thing you can do is to grind that complete area. Looks like you'll need about a 6-8" round area. Then use fiberglass matting and resin to hold it down.
Then grind it, bondo it, prime it, then paint.

You might want to try a small flat screw to help hold that down. You will see this from underneath (possibly), depending on how the hood was cut.

Hope that helps!

 

[56_Kruiser]

Taz...I appreciate your input.

I am not considering ditching the fiberglass scoop, and getting a 69 Z-28 repop hood with the induction scoop, and cut it off and weld in place of the fiberglass one.

I'm not sure how much trouble that will be, but would alleviate this problem. My main problem right now is getting measurements of the scoop to see if it is the right size to make work. I've posted queries on 3 different Camaro forums, and getting no help there. But I've got some time before I have to pull the trigger.

 

[TAZ]

That sounds like a good idea to.
Does anyone make just the metal scoop or a all fiberglass hood w/ scoop for your car?

 

[56_Kruiser]

That sounds like a good idea to.
Does anyone make just the metal scoop or a all fiberglass hood w/ scoop for your car?

Goodmark does make just a scoop, as seen here. But, it is too long. That length is pretty much the same measurement that would be from the back of my hood to the front. And I"m sure the curve of the hood wouldn't match that scoop. And it doesn't match the design of what I'm seeking, which would be like what is on the car now:



This hood is what I"m considering.

I'm concerned about the fit. When you call them, the sales person of course isn't able to get dimensions. They tell me it is supposed to be a 'factory fit'. So, I've posted on 3 camaro forums asking for a favor of a measurement, but haven't had any luck getting a response yet.

I'd like to get measurements as outlined on the image below.

 

[TAZ]

Definitive some critical measurements.
Also the curve is critical like you said.

Man, that scoop looks so good on that hood and there is so much work involved already, it there are no other issues except the corners, why not work with what you have.
Even with welding a scoop on, you're going to have to be very careful not to warp is since there isn't any support for the scoop hole.
I'd just remove the hood and make sure that it's reinforced on the top and bottom corners.
That's my opinion though.

 

[56_Kruiser]

...Man, that scoop looks so good on that hood and there is so much work involved already, it there are no other issues except the corners, why not work with what you have....I'd just remove the hood and make sure that it's reinforced on the top and bottom corners.
That's my opinion though.

Over in the 61-64 forum, I have quite a few saying I should abandon the scoop, that it doesn't look good. They are likely more 'purist' in the restoration department.

By reinforcing, I presume you mean with the fiberglass matting as you mentioned earlier.

I'm not experienced with that stuff. I presume I'd need to get it on and then build upwith the canned fiberglass resin stuff.

My big concern is it cracking back out. I tend to have my custom cars paint last a long time. I had 16 years on my first candy job on my '56, and the current red job has been on since '99, and it's very good still. Of course, no opportunity for fiberglass to be cracking on it.

 

[TAZ]

Since you're not experienced with fiberglass, It's probably best that you go with metal then if you're looking for 10+ years.
This is assuming you are a very good welder and can do very good bodywork.

 

[56_Kruiser]

Since you're not experienced with fiberglass, It's probably best that you go with metal then if you're looking for 10+ years.
This is assuming you are a very good welder and can do very good bodywork.

I certainly would not classify myself as a very good welder, or very good at body work. That being said, I ended up with a nice finish on my '56 which required a weld in of a rear clip from a 4 door; quarter panel patches; a floor board from a 4 door; and new door skins. While I don't consider myself 'very good' at body work, I do get it done pretty good...it just takes me longer than a person trained in body work. But, I have to confess, the body work was 30 years ago; the current paint on it was 14 years ago.

JFYI...I sanded some on the scoop area today, and find it was attached with rivets; then fiberglass resin over it; then putty.


I'm leaning toward getting the Camaro hood and trying to cut out the Induction scoop and welding it in this hood. I wonder what the chances are that it can be done w/o too much warping. May find out.

Wish me luck

 

[TAZ]

The only problem I see is the aftermarket hood will be a little thinner gauge than the stock hood. You should be all right with that experience then.

Looks like it possibly would have held if they moved the scoop back a little so the flange is at the very edge of the hood and the scoop was overhanging the cowl more.

Good luck to you Hope it all works out!

 

[chopolds]

Fiberglass to metal is usually never a great idea. Different heat expansion rates, plus the vibration issue on a hood will almost always crack it.
I did a 55 Chevy for a friend, who really loved the 'glass teardrop bubble scoop on it. I had him buy a new 'glass hood, then grafted the old scoop onto it. Worked great.
If you decide to go with a metal scoop on yours, and aren't a great welder...or even if you ARE.....do this to minimize the warpage problem on a mostly flat hood.
Carefully measure out the area where the scoop needs to go. Mark it out on the hood. mark off about 1/2 in. inward of the shape of the scoop. Double check your accuracy. Using a T dolly, or even a piece of solid rod, or heavy tubing, about 1/2 to 1 in. diameter (or match the radius of the existing curve from hood to the sides of the scoop) , hammer up the inside of the area where the scoop is going. Go to 90* or so. Be sure you are still exactly where the scoop sides will be! measure up exactly 1/2 in and trim it. Now cut off 1/2" off the bottom of the scoop and them weld it to the hood.
You are not welding on the flat part of the hood any more, and the weld bead will be on the vertical sides of the scoop. so welding warpage will be trapped there, and be minimal, and easy to correct. Very little filler will be used as well, if you are careful and work slowly.
Believe me, you don't want the problems you'll have welding the scoop to a flat hood!

 

[56_Kruiser]

chopolds...I really appreciate your detailed input.

I have decided to put on a metal scoop. The '69 hood is supposed to arrive tomorrow.

I took off the old scoop Friday:





As you can see there is a hole already in the hood from the previous installation. From measurements I have, I think I may be able to attempt what you are suggesting.

Question: Does your method expect me to mate the scoop and raised part on hood edge to edge (ie butt weld), or just have the radius of the scoop overlap the raised part on the hood a bit, and weld on the radius? I'm thinking in any event it may be difficult for me to achieve that. But I'll sure give that a go.

I am not a body man by trade, and have no training on that. I have done quite a bit of it over the years (well, I guess it's relative...not that much for a professional body man). At any rate, I don't even havce a T Dolly, and not sure of proper methods to use it. I'll investigate. I'm sure there are Youtube videos on it.

Probably the biggest challenge will be if there is enough metal real estate there (given there is a hole already) to achieve the goal.

 

[chopolds]

Always butt weld outer panels. It is easier to hammer them straight, they won't "witness up" like an overlapped panel will, as it is too thick and won't flex as much, or contract and expand the same as the surrounding sheet metal. An overlap will also trap moisture and begin to rust out much quicker than a butt weld.
Learn to do fitment the best you can. It really pays off in less welding problems, faster welds, and easier correcting warpage. Contrary to most adviece, I like to have a real tight , no gap seam to weld. If your welder is set correctly, you'll still get good penetration, and I find welding with even a small gap can blow away edges easier. If you progress to TIG or gas, then a tight fit is even more important, so learn to fit panel up correctly to begin with.
You can even use heel dolly to make the radius if you have one available, if it has a rounded radius on one side. A T dolly just makes it easier, not that you HAVE to use one.

 

[56_Kruiser]

I'll make an effort to get the hood scoop project butt weldable. I'm a bit pessimistic about successfully doing that. I'm more confident of getting a decent match for the quarter panels than I am for the hood. But I'll take my time, and make the effort. Maybe I'll surprise myself.

I'm not sure what type of welder you would call what I have. It is an OLD Linde wire welder, which uses argon gas. I haven't welded enough to get what I would consider good. I thought about getting a new mig welder, but they're so expensive to get, given this is probably the only project I'd use it for. There are a couple inexpensive ones by Chicago Electric at Harbor Freight. I know they wouldn't be worth a darn for a professional that would use them a lot. But may be good enough for me for a small project.

I'm going to practice on some of the scraps left over from cutting the panels for the car.

Thanks again. You input is very helpful.

 

[TAZ]

You got that scoop off! Cool.
That glass dust sure makes a mess though. Sure you'll be glad to get that garage back in order.

 

[56_Kruiser]

Got a problem...

Interesting that I posted the thread about Lord Fuser. Don't know what actual product was used, but the induction housing on the bottom of this scoop is attached with something like that.

Of course I don't know what product was used. I found something about one brand that said to soak in acetone. I called Lord, and they said to get items apart with their product, need to heat the meetal to 400 degrees. I don't know if that's hot enough to cause a problem or warpage to the scoop or not.

Any suggestions on removal?

Below is a picture showing the part that is 'glued' to the hood:

 

[TAZ]

I wonder how much of that was a applied to bond it on.
If it's just around the edges, possibly you could use one of those small propane torches you can get at Lowes or Home Depot.
If they used quite a bit, possibly use an air chisel and a gasket scraper blade and carefully brake it loose that way.

I guess I would probably use the latter no matter what.

 

[56_Kruiser]

It actually is a puddle that is near 1/4" thick, from what I can tell.

I'm a little scared of using my air chisel on it, as I may screw up the scoop itself.

I am going to play with my small propane torch on some of the hood itself, and use my laser heat gun, and see how it looks heating to 400. If that doesn't seem to mess things up, I may give that a go. Then if that fails, I'll probably head down the route you mentioned, cutting it back to where what is left is what is stuck on, and see what I can do from there.

I may try pouring some acetone down in there and let it soak. Who knows, maybe that'll loosen it.

 

[56_Kruiser]

Well, I got the piece off from under the hood. I first tried letting acetone soak on it, but wow, that stuff evaporates fast. No go.

So, I did the propane torch thing. Watched temperature with the laser temp gun. Let it get to 400. That did the job. As you'll see below, there were 6 puddles of adhesive. Once I got one off, I could see better and focus on the others.

 

[56_Kruiser]

Moving Forward...

I'm debating now about how I want to finish this up . The hood as original had the indention on each side of the center. Normal width can be seen from this picture on a Google search.

Looking at the picture at the bottom of this post, I got to thinking, it may look good if I just have the indentions still there like an original, but narrower. With the fiberglass hood, the inside of the indention wasn't really indented, but with the scoop there, it looked like it was:



The edge of the black scoop on the picture below outlines what I'm thinking would be the inside lines of the indention. I could accomplish that by lap welding the scoop on, instead of cutting the hood to butt weld it.

Chopolds...if you're reading this. what do you think about lap welding it. I do know that I cannot do what you suggested (work the hold edge up on the hood in order to weld on teh curve. The hole in the hood is too large already.)

Not sure if I like one look over the other. The welding consideration may make the difference on how I decide.