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[rick walters]

I thought I would share my success in repairing the infamous rusted area for the battery.
I have a Martini Rossi that I am restoring.
When I bought the car from the original owner, his idea of repairing the rusted area was to bondo it, oops.

I have worked with epoxy resins in the past on a sail boat restoration, so I was inclined to consider the use of a epoxy resin with fiberglass. I have never worked with fiberglass. The epoxy work was on a woody sailboat.

Since there were some areas that had rusted completely through on the floor of the battery box as well as the loss of a good portion along the fender side of the box, (this is why bondo is not good idea, it does not prevent the leakage of water under the bondo given the constant bouncing of the battery in the box) I had a decision to make as what to do in repairing and strengthing the rusted out area.
I knew there was no way I was going to have a new piece of metal welded in given it location and the interior conflicts possible during the welding process.

After careful research of various products and calling several technical departments for their thoughts as to preparing the surface for the epoxy I settled on this solution.
For the box floor area I purchased a small sheet of metal and sized it to cover the the rusted out area.
As for the side of the box I left it as is.

I sanded all the areas of rust and also the surrounding side areas.

I then purchased a metal epoxy compound called "Metlweld" from System Three. This epoxy bonds all types of material together and just as important it creates a new metal surface for better bonding when applying the fiberglass epoxy.

Once I covered the entire area that I was going to fiberglass, and bonded the new metal piece to the box floor with the Metlwed I was ready for applying the fiberglass.

I sanded the newly applied Metlweld epoxy to creat a binding surface.

I used 6 oz cloth mat not woven.

I decided to use the "Silvertip Epoxy" also from System Three as this has great durability and bonding properties with metal.

I then followed the basic techniques for applying three layers of fiber- glass using the epoxy and most importantly I made sure that the third layer applied to the box floor was finished so no fiber glass strands were showing. This can be accomplished during the green period of the curing process by either applying more epoxy or using the System Three "Filet Epoxy'.

FYI; for the side of the box, the fender side with 90 degree angle I cut some additional strips and applied a total of five layers of fiberglass.
For some rusted out small pin holes areas I simply used a small pieces of duck tape to prevent the epoxy form dripping through to the insulation under the dash. The fiber glass process sealed the tape for ever.
For the corners I cut ovals shapes and applied three layers.
After allowing the epoxy to cure completely I then sanded and prepared the floor for primier.

On the side I repaired, I realized that since there was a rather long almost the full length of the side rusted out area that it was not important that the fiber glass be laid off completely at 90%. In fact since there was a hole the fiberglass did in fact concave as I expected.

Therefore, in order to finish the 90 degree angle as if no repair had been done, I applied a couple of three bondo applications to the sanded fiberglass and then sanded and prepared it for primer and paint. I also used bondo for feathering out any small areas where the epoxy was uneven, i.e. the corners.

FYI; you need to put tape or rubber caps on the bolts for the battery hold down brackets.

Also if you use the Metlweld keep in mind that it is extremely hard to sand and fair out, so only apply where you want it. I ran the fiberglass epoxy just past the Metlwed so I could fair the epoxy rather than the Metlweld.

Some final thoughts on the epoxy. A little goes a long way. You are forced to purchase the smallest portion available which is way more than you need. The Metlweld comes in pint size amounts more than enough to do the job.

Secondly, it is absolutely important to mix the epoxies in the right proportions and use the same way you did it from the beginning. If you pour out the epoxy first then the hardener then do it the same way every time.
You do not need to panic if you do not mix enough epoxy, simply make another small batch and keep going.

If you mix to much you will know it when you see the reaction in the mixing pot form the harder starting to show fumes. The pot of epoxy hardens quickly and creates heat since it is in a very confined. If this happens throw out the mixing potit is hot so be careful when you pick it up, and mix new. Thus the reason for having several measured marked mixing pots on hand. They are cheap and having to redo the entire fiberglass job is really not appealing.

Finally cut your layers of fiber glass with very sharp scissors this reduces frays and lay them out in the order in which you will apply them. Start with the smallest layer first and then layer on the next larger size and so on.

Here is the break down on cost about $110.00 that included a small sheet of metal, application tools, mixing pots, fiberglass, epoxies and good protective gloves not the cheap doctor’s type. I purchased all the items from Jamestown Distributors (google it) except for the sheet metal; got it from True Value. The bondo I already had. I used the fiberglass type bondo.

Yes, I was a little nervous in applying and working with some new materials in such a confined area, but truthfully it all went away once I started the process.
Good prep work, tools, and materials will make the difference.

I hope some of you that are suffering form the "rusted battery box syndrome" will find this of value.

Let me know if you questions.

My body/painter guy who is going to paint the car when I get it stripped down later this month, came over and looked at the finished job and said "you did that, it looks great" We will see once the primer is painted. I do know that the battery box is as strong as before if not stronger and there will be no leaks or further rusting.

Good luck,
Rick

[Scorpio]

so much writing.....so little gaps....so little pictures..

You lost me after the first sentence
_________________
1979 NA
MS1..EFI..
GARRETT T25 TURBO
BILSTEIN SHOCKS
GT BASED CUSTOM BODYKIT

Brisbane , Australia
Think mean think fast
all youll see is
my Porsches Arse!!!

[Andre']

Here's my solution - I don't believe in expoxy as far as body repair work is a concern:

http://www.impatientcreations.com/Current_Projects/88_Porshe.htm

The donor battery tray is from a 1989 944 Turbo - has the additional water drain to the fender side. Not the cheapest solution but solid...

Andre'[/b]

[Frank.Ind]

Seems like a lot of hassle when you could of just welded new metal in...

[Andre']

The battery tray is a lot of work - no doubt about it! Especially since I gutted the car out on the inside to prevent damage to the A/C box, dash and carpets. Depending upon your relationship to your car - yes - you can "just weld" in new metal and be done with it! Make sure you sell it quick because your "fix" won't last long since the battery tray is part of the longitudal channel as well! And the damage won't stop right there; in my case we had to replace parts of the channel side wall, and the inner fender (the battery acid indeed did a fine job eating away the zinc layer)!

After all this work it is almost impossible to tell that the battery tray has been replaced! And the new tray came with the side drain, which is a really nice upgrade (by the way, the drain on the drivers side already has 2 drains). Since you guys in Britain drive on the wrong side of the road everything I said must be reversed...

Was it worth it going through all the hassle?! You tell me...

[Frank.Ind]

Just went about doing mine differently. so IMO, no it wasnt worth the hassle

As the hole in mine was bang on in the middle of of the tray I cut out the old an let in the new. To avoid burns I made an MDF box and held it around the area being welded. This worked perfectly and absolutely no issues since (repair was 18 months ago).

Im not to sure what you mean by this:
"Make sure you sell it quick because your "fix" won't last long since the battery tray is part of the longitudal channel as well!"

I can only assume you think the panel has some strenghting elements.
This maybe the case but the scuttle face will be doing a hell of alot more.

[Andre']

[quote="Frank.Ind"] As the hole in mine was bang on in the middle of of the tray... quote]

Obviously you haven't completely read and understood my reply...

[Frank.Ind]

Clearly
It is noticeable however that:
A. You somewhat lack in manners.
B. The pictures provided arent the greatest
C. Im English and so some American terminology means very little to me.

Ultimately it seems your job is car repairs and this was probably a paying job. I would love to see the bill with the interior strip and replace...

The same method I used with the MDF would of worked perfectly well and saved your customer (or even you) a hell of a lot of time and money.