Bubba Was Here - Fiberglass Repair Question

[Michael A.]

Tearing out the interior on a 42 year old car is a bit like an archeology expedition. I've found and saved numerous "inspected by" tags along with a small treasure of change. While removing the original carpet and jute pads I have uncovered what appears to be the remnants of a meatball replacement of the antenna at some point in my 66 roadster's life. (see picture attached). You can just see some Bubba with a drill hacking away at the backwall to provide an opening to easily get to the antenna.... makes you kinda of sick!

Any thoughts as to what I should do with the hole? I am not doing a full restoration at this point. Just getting the car ready be comfortable for my summer journey on Rte. 66. Should I seal this hole up in some way for a temporary fix or should I just leave it until I do the proper restoration at some point in the future? There's no indication that there has been any water come through this hole in the past. The wheel well is sound and the spare tire tub are in place so this is fairly remote spot. When it does come time to restore the car, is there a process someone would recommend to do a final repair?

I'd appreciate any thoughts.

Cheers
Mike

[Wayne W.]

Re: Bubba Was Here - Fiberglass Repair Question

Now thats something the General should have thought of. An access hole for the antenna. Sure easier than removing the muffler. I give bubba an A for that one.

[Kevin M.]

Re: Bubba Was Here - Fiberglass Repair Question

Michael,

When you get to restoration making a patch piece will be very easy, someone on the board might even have that piece. Now you'll have to check the archives on "how to" but I think if that's all the damage buba's done your lucky.

Kevin

[Michael A.]

Re: Bubba Was Here - Fiberglass Repair Question

Now thats something the General should have thought of. An access hole for the antenna. Sure easier than removing the muffler. I give bubba an A for that one.

OK, score Bubba 1, the General 0.

It sounds like you'd suggest leaving it there until I do replace the antenna with a correct replacement at some future date. Is that right?

Wayne, I also posted a follow on to the radio wiring help you gave me last week. Your help was perfect and I now have a working radio. Thanks. You may not have see the follow on so I'll send it to you directly via email.

Cheers
Mike

[Chuck S.]

Re: Bubba Was Here - Fiberglass Repair Question

...While removing the original carpet and jute pads I have uncovered what appears to be the remnants of a meatball replacement of the antenna at some point in my 66 roadster's life. (see picture attached). You can just see some Bubba with a drill hacking away at the backwall to provide an opening to easily get to the antenna.... makes you kinda of sick!...

Well, you sucked me right in on that one...I click on the picture expecting to see a 1" diameter penetration for a cable, and Great Gobs!, you have an ugly trapdoor opening in your rear bulkhead!

For a hole that big, the best approach will be to square up the sides of the hole, and laminate a donor piece of fiberglass into the opening.

If you're like me, you won't have a perfectly flat piece of fiberglass laying around to fill the opening. You can check with Corvette image...they may be able to supply you with a donor piece; this will be a good idea particularly if the area has any molded ribs running through the patch.

You can skip the donor piece by backing the hole up on the backside using aluminum flashing waxed with paste floor wax, and just laminate about 3-4 layers of mat and resin over the opening, then do the same on the other side...you'll use more mat and resin, and it'll be more trouble. For full strength, fiberglass repairs should always be laminated on both sides unless the backside is just not accessible.

Judging from the size of the hole, I would say 2 onces of resin would be close for finishing 3 layers of mat around the donor piece joint...if you skip the donor piece, the size of the mat pieces is going to require about 1 once per layer...just eyeball guessing here. In your haste, don't forget to "roll" each layer of saturated mat after it has been laminated to force out air bubbles...it'll be stronger, and you won't have as many voids if you do any finishing to the repair.

The general technique for fiberglass repair is to taper grind the outline of the opening or crack starting 2" back from the repair. Grind the existing fiberglass to zero thickness at the edge of the hole or crack to be repaired. If you are using a donor piece to fill an opening, then the perimeter of the donor piece will also be taper ground to zero thickness at the edge.

Pre-cut fiberglass mat pieces to fit the type of repair you plan to make. Some people say to tear the mat for a smoother blend at the edge of the repair, but I've found cutting the mat pieces to size using an expendable pair of scissors yields much more predictable results, both in the mat pieces to be used and as a final result after lamination.

For a donor piece, you will laminate resin and mat around the joint, and if you've taper ground starting 2" out, you'll need mat pieces 1.5", 2.5", and 3.5" wide. The different widths of mat compensate for the ground taper, and will keep thickness of the repair about the same everywhere. It should be obvious, but plan on taping the donor piece in the hole from the backside using masking tape.

Pour out the amount of resin you plan to use, and catalyze with 12 drops of MEKP per ounce of resin. I have found I can only mix and use about 2 onces of resin at a time before it begins to gel on me. You can experiment with cutting back on the catalyst, but I like guaranteed results even if I have to mix more often.

Work quickly to mix the resin and catalyst well, then using a disposible chip brush (Harbor Freight has the best deal on chip brushes), paint the ground area where the first 1.5" wide pieces will be applied; saturate a strip of mat, apply to the painted area, and roll out the lamination. Apply first all the 1.5" wide strips centered on the joint line and roll out as you apply...then all the 2.5" wide pieces centered over that, and finally the 3.5" wide pieces. By the time you roll out the last layer, the edge of the resin and mat will about cover the ground area.

If you plan to skip the donor piece, the process will be the same except you will now have mat rectangles about 8" wide X 10" high judging from the size of the hole. I would use an adequatedly sized piece of plywood covered with waxpaper to lay the mat pieces on while brushing on the resin...saturate each mat piece, but don't leave a lot of extra resin on the surface.

Try it...fiberglassing can be fun. But, it won't be unless you learn to keep your hands clean...wear latex gloves and change them frequently; i.e. when your fingers begin to stick together.

[Michael A.]

Re: Bubba Was Here - Fiberglass Repair Question

Chuck
I figure Bubba had a pretty big hand he wanted to get through the hole. It sounds like at least Wayne Womble thought Bubba had a better idea than the General! I have to admit that it was easy to connect the new antenna wire by working through the hole.

Thanks for the detailed instructions. From the sounds of it, I will leave this to when I take the car down for the full restoration. That is at least a few years off. But I will be saving this post to reference.

Thanks again and STW

Cheers
Mike

[Chuck S.]

Re: Bubba Was Here - Fiberglass Repair Question

...Thanks for the detailed instructions...

Good luck...it's fun; you'll enjoy being able to do it yourself. BTW, detailed instructions are much easier to come up with when you recently had to remember and apply those very same steps yourself.

[Denny J.]

Re: Bubba Was Here - Fiberglass Repair Question

Make a donor pcs of fiberglass on the work table on a pcs of foil, than when it some what hard take a razor knife and cut to size using a paper template of hole use a hot glue gun to hold in place and than fiberglass as Chuck said