What do you recommend for repair of Fiberglass Hood Scoop Repair


The way I suggested was probably the best way to do it, esp. for someone not very experienced with doing hammer welding.
The problem arises, when you weld on the flat part of the hood, that you WILL get warpage. The flatter the area, the worse it will seem...the larger the area that will be displaced by the shrunken weld seam.
So......if you do an overlap weld, 1. you will have a bit more strength in the weld seam area 2. That is not necessarily a good thing...it will be harder, or impossible to correct any warpage 3. overlaps invite trapped moisture & rust & 4. since it will have different expansion & contraction rates, you will see the seam even if your bodywork is perfect, you'll see them at different temperatures.
Butt welding pretty much eliminates all these problems. It just takes more care and time to trim the metal just right to do a good butt weld. The hammer and dolly work afterwards will help eliminate the warpage problem. It IS worth the time and effort! Just very difficult for a beginner. You dont' really want a ton of bondo on a hood...same reason for not bonding the glass scoop on it...heat and vibration will eventuall cause it to fail.
You can try and splice in the scoop on the flat part of the hood, but you'll be figthing the warpage problem a lot.Just take your time, and do lots of tack welds, skip around a lot, takes breaks to let the metal cool, just be very carefull with your welding and you'll have less problems. It can be done, but it's a lot harder to do, that's why I always try to do it the way I suggested.


New member
Thanks for the input..

So, I'll plan on butt welding. Due to the hole that had previously been cut in the hood, I cannot do per your original suggestion.

I actually plan to take a lot of time, and do pretty much all tack welds...stringing them together (albeit hopping around to different spots so as to not put too much heat in one area).

ONe other question...what's your philosophy regarding quencing, either with air or water? (Seems to me I've seen mostly air used bu those who like to cool the welds).


Lots of debate about this subject...I have my thoughts, and several other master metal fab guys agree.....the heat of welding shrinks the weld seam. It doesn't matter how quickly you cool it, doesn't have much effect on the shrinkage. BUT....rapid cooling WILL slightly harden the metal, making it a bit more difficult to work it, with hammer and dolly. This is also why MIG welds are more difficult to work, they heat fast, and cool fast, so the welds are more brittle, and more prone to cracking than TIG or Gas.
On the other hand, lots of MIG guys seem to use air, and think it helps. I dont' know...