MajD

Here are some better pictures that illustrate my situation. The crack is located on the passenger side inner fender and goes to the fender well bonding seam. I checked and can't tell for sure, but I don't think it goes under the seam. This crack was exposed when I was cleaning up this area in preparation for primer and undercoating. I thought it was a glob of paint, but when I got the putty knife under it, a chunk of resin and fiberglass fibers came off. I'm pretty sure it was repaired at the factory.

The second picture shows the separation of the adhesion bond. this is the same fender well but the front view. The rear was similar, but I shaved it back with a heat gun and razor until I got to where the bond was attached. Here, its completely pulled away and removing it will leave nothing in its place. So here are my questions:

1. Do I have to remove the fender well to properly repair the crack?

2. I was planning to use evercoat to replace any missing adhesive. Will this bond with the existing adhesive if I rough it up with sand paper? Is there a better way to repair this? Thanks.

DUB

In your FIRST photo... it will need to be ground on and prepped so you can laminate in resin and matt. I would use WEST SYSTEMS EPOXY RESIN for this repair. You HAVE TO make sure that when you are prepping it that you grind away the fiberglass and get to good solid fiberglass.....BECAUSE this type of body material is made out of sheet and can crack laterally....so the prepped area can get quite wide. There is NO REASON that you have to grind it down so much and far out that you crack on the outside gets extremely wide....UNLESS the body material requires it when grinding it away. When you are grinding it from the underside ...you DO WANT TO make sure that you taper your grinding so when you go and laminate it...you will be able to lay the fiberglass matt and resin and and it will lay down nicely.

You will know when you get to good solid fiberglass when the fiberglass is dusting away...and not throwing off chucks where the sheets have separated and can fly off easily. DO not run your grinder at top speed. I find that a moderate speed works better.

As for the SECOND photo. If the panel is still attached and it is just the end of it where it looks weird. You can prep and fill it in with some Vette Panel Adhesive.....because that little area will not hurt anything. IF it has lost its bond...then you need to use the Evercoat SMC Panle Adhesive part number 994 to correct this.

DUB

MajD

Thanks DUB.

MajD

DUB, I have a few more questions. I was getting ready order the West system A kit, but I'm going to need some fiberglass mat for filling the area after I grind away the crack. I've read that some of the mats are not compatible with epoxy resin. What would you recommend?

Also, for a repair this size, I'm thinking the 205 fast hardener would be fine as long as everything was prepped (i.e., glass mat cut, area cleaned and prepped, etc.). Would that be OK?

Finally, if I have some other bonding work to do, so I'm probably going to get the Evercoat 994. Can I just use a putty knife to shove this is the crack where the old adhesive comes out? I've read where guys have prepped the surface with sandpaper, but I'm not going to be able to get any in there very well. Thanks.

DUB

I get mine form a fiberglass fabrication shop down south from me. 'Google' it and see if WEST SYSTEMS has it. I know it is available in many boat suppliers....and possibly in the aircraft industry.

You can use the 205 'fast' hardener....but I prefer the 206 'slow' and give it time. You are not in a race to get it done....so give it time.

ALSO...when you are getting your patterns of mat to size...I prefer to make sure I do not have a straight cut line in my pieces that I am using...especially if I do not have straight edge I am laminating to. I PREFER to have frayed edges of the pieces...they lay down better in most cases and you do not have a sharp line showing where the patch stops. SO I tear the fiberglass with my hands so I get the frayed edges.

I can tell you this.....the lip or cracked edge at the wheel well opening is going to be a ROYAL PAIN...because you will literally need to apply strands so you can control the way that they lay...because if you use a patch....it more than likely NOT stay where you want it.

The 994 does not like to be applied in thin layers...so if you plan on packing the area of concern...make sure you apply enough.

DUB

MajD

Thanks. I'll see what West Systems has or call them and see what they recommend. It seems like if I'm going to be laying down individual fibers, I should get the 206. They probably sell unmatted fiberglass that I could use in that area.

Regarding the separated bond, After working on for a little while this evening, I took a picture of the progress. As you can see, the dark spots near the adhesive are dirt that has gotten between the panel and the adhesive. It is well bonded on the fender, but the inner skirt bond on the inside wheel well seems separated. The space between the fender skirt and fender is filled with dirt and crumbling adhesive. I don't know how far yet, but I'm guessing a third of the way up.

I took a picture of the fender skirt front, and you can see that bond is in good shape. And finally, I took a picture of the end of the fender skirt to show you how large the gap is between the skirt and fender. This is only on the end and it gets narrower.

Should I continues the way I'm going or should the whole seam be removed at this point? Also, is the gap at the end of the fender skirt too large? Thanks.



About two inches removed





About four inches removed





Front bond seems nice and tight.





Gap is about 1/4".

DUB

Not meaning to make 'light' of what you have noticed. But...honestly I see this often and I really do not give it much thought. The ONLY thing that I am concerned with is if I see something like what you have noticed. I check and see if the panel is bonded. If it is bonded...I usually let it go after doing a small test and see if the separation has any merit.

WHY do I do it this way. Because...NO JOKE...I have removed fenders and quarter panels and have seen areas where that was VERY LITTLE adhesive actually bonding the fender or quarter to the bonding strip. Seeing this many times. The only way I know a Corvette will not have a problem with ANY seam would require me to pull all the panel apart and bonding them all back on....and I am not going to do that....and 99.5% of my customers would not pay for me to do it.


If you are concerned and have to get these areas corrected to your liking...you may have to grind out the adhesive and apply fresh adhesive. As for the wide gaps....'it is what it is' and unless you get the panel separated and get the adhesive out...like I wrote...I do not give it a thought....because I see it all the time....and if the panel is bonded....it is only a visual thing.

If you can pick out the adhesive in the first photo and slide a piece of sandpaper in the seam to clean it...this is usually my method if I am filling in adhesive in an areas where the panels separated

DUB.

MajD

DUB, thanks and no worries. I'm actually glad it's not a big deal because I'd really rather be prepping the fender wells and engine compartment for paint than picking old adhesive out of cracks. My main concern is the integrity of the bond and not the aesthetics. Sounds like things are OK there. You did mention a small test you perform in the separations. Can you elaborate on that as it will help me understand which separations need dealing with? Thanks for all your help.

DUB

Commenting ONLY on the seams of an inner skirt.... like what you have shown.

Sliding a thin end of a screwdriver in the crack and the seam and turning it and seeing if it widens. Or grabbing on the panel and pulling in it slightly and watch the seam and see if it widens. It depends on where the seam separation is and actually how much effort it takes to get it to widen.

DUB

MajD

Thanks for the info. I think I have enough now to go on and appreciate all the help.