KS69Coupe

Wondering if someone has a nice close-up photo of the inside rear battery compartment reinforcement hold down area. I'm doing some fiberglass repairs to mine and would like a photo of what it should look like when I'm done. As you can see once I took the battery out and removed the rear reinforcement the fiberglass is either gone or soft and I'll need to reglass and repair both the rear inside and the underside of the battery compartment on our 1969 Coupe.

Will do the inside compartment repairs and then move to the underside and do some repairs there too.

Thank you in advance for your help.

Kevin


Current state inside the battery compartment, rear battery hold down reinforcement

Old and new underbody rear hold down reinforcement

toothpick in the center is the center location of the 1/2" wrench bolt for the rear battery hold down.

KS69Coupe

Used the new replacement underbody reinforcement plate as my form.

Used parchment paper and underbody reinforcement plate, lowered the reinforcement plate down from the inside to create a gap between the plate and the battery compartment fiberglass base, then used bondo glass and a disposable large injector to squirt / pump the fiberglass into the void, put the small nuts on the bolts and snug tightened the platte up against the battery compartment base to force the bondo glass into all the cracks and crevices and gaps.

I made a form for the front repair area out of popsicle stick, cardboard, lined with parchment paper, and tape to hold the front repair area in place and create a form. Used the injector with bondo glass to squirt and fill the gap space between the form and the battery compartment rear support.

Will let this set overnight and then use my Dremel to finish shaping the inside battery compartment repair.

underbody support used as my form for the repair area.

Fiberglass was rotted out, metal support plate is taped to the bottom of the battery compartment, lower it down to line the hole with parchment paper so the bondo glass would not stick to the metal reinforcement plate

made a front form out of cardboard, parchment paper, and a popsicle stick and painters tape to hold the form in place

injected bondo glass into the form and into the gap space between the bottom of the battery compartment and the parchment paper lined metal reinforcement plate and then snug tightened down the nuts to squeeze the bondo glass into the gaps

disposable injector puts the bondo glass into the small gaps and the form helps keep it contained until the bondo glass hardens....about 3 minutes so you have to move pretty quick or it will set up in the injector

theandies

I actually have my battery box opened up good as I'm putting a Holley Sniper 2 in now. I'll snap a picture when I'm back at it this weekend if you can wait a few days.
Yours look light years better than mine did before I fixed it. I was shocked it could even hold a battery in. The entire bottom of my box needed reglassing.

KS69Coupe

Sounds good. Thank you in advance for sharing pics.

P.s. Bottom of the battery compartment on my car is not too bad, pretty solid. The bolt hole was another story, pretty soft and rotted out but I was able to Dremel away material until I hit good fiberglass.

theandies

Here are the pictures. Keep in mind I did this about 20 years ago so it need a fresh cleaning . I haven't been this deep into my battery box since installing my crate engine and repairing the massive damage to the box. It was eaten and saturated with acid. I cut out the bad area and made a mold from under the car the hold everything up and layered glass mat and resin over and over. I really guessed at the hold down bolt area by just guessing the shape by the new undercar bracket I bought. It's probably not perfect but it works like a champ. I have no problem getting the bracket in place and the bolt started. Everything lines up perfectly.

KS69Coupe

A lot of work on your part but it turned out really nice. I was able to do some test swatches to match the color of the existing fiberglass. The results for color were good using my fiberglass resin, trial and error (gel coat white + black mixtures at different ratios), wax, and hardener. I'm happy with the results on my benchtop but I think I'll do one more round of tests with some of my fiberglass strands chopped up in the final mixture and apply that to an inconspicuous area to see how is looks before doing the entire underside of the battery box.

I think I'm ready to go ahead and complete the repair. Thanks for your help, theaandies!

CraigH

I did a number of repairs on my battery box. It had been hit heavily at some stage and broken. It then warped over time.

covered it here….. https://www.corvetteforum.com/forums...ourney-77.html

KS69Coupe

Hi Craig,
Thank you for posting the link to your underbody repairs and restoration. It took me awhile to get through your previous link and photos because I was going really slow and admiring all your detailed workmanship. Battery and Jack boxes turned out beautiful. Few tips I picked up: taping off the repair area, grinding the taper into the previous glass, and using the tape as your depth gauge for the new fiberglass repair. Great idea to get the old and new surfaces flush.

Really nice work - thank you for the help.

Kevin

CraigH

Thanks Kevin, I am sure your repair will turn out great. Just take your time and the great thing about glass is if your not happy just grind it and lay some more till your happy.

Craig