radiator shell refurb question

bobgreco

bobgreco

Senior Member
I have an original 1929 radiator shell that I would like to paint black for my 1929 CCPU. It has been grit blasted, but has a bunch of pitting and a few through pin type holes. Maybe a dozen or so. I am afraid that if I use regular body filler, the inherent flexing of this piece will cause the filler to pop out. Someone suggested using fiberglass on teh back side to add a bit of strength.

Any thoughts out there?

Thanks a bunch.

Bob
 
I wouldn't worry about the filler coming loose if you prepare the metal correctly before applying the filler. If you get all the old nickel plating removed, get all the rust pits cleaned well and scuff it with some 80 grit sandpaper before putting on the filler, you should be fine. If the pits are not real bad, you could use a high build primer like Evercoat FeatherFill or similar primer instead of a filler. I don't believe the shell will flex all that much. You should definitely weld up any pin holes and because if left, they could cause a rust bubble later by moisture getting through the hole. You can use a copper plate behind the pin hole to dissipate the heat and provide a backing for the weld. The copper plate will just fall off when the clamps are released. Hope this helps.
Rusty Nelson
 
wrndln said:
I wouldn't worry about the filler coming loose if you prepare the metal correctly before applying the filler. If you get all the old nickel plating removed, get all the rust pits cleaned well and scuff it with some 80 grit sandpaper before putting on the filler, you should be fine. If the pits are not real bad, you could use a high build primer like Evercoat FeatherFill or similar primer instead of a filler. I don't believe the shell will flex all that much. You should definitely weld up any pin holes and because if left, they could cause a rust bubble later by moisture getting through the hole. You can use a copper plate behind the pin hole to dissipate the heat and provide a backing for the weld. The copper plate will just fall off when the clamps are released. Hope this helps.
Rusty Nelson
Click to expand...

Great advice Rusty!

Pluck
 
Bob, I had real good luck with Transtar 61 61...A high build primer. I used it on My 48 chevy 1/2 ton...it had pits on the hood and fenders, I've been driving it for three years or more with no problems...well I do have one big pit in the front of the hood...only had 500 mi. on it and was going down the interstate about 75 mph at night, and out of nowhere came this owl ( glad I wasn't on my motorsickle ) left a dent about the size of a bowling ball. Anyhow your radiator shell should be a breeze with this stuff...three heavy coats...sand between coats. Like wrndln said be sure to prepare the metal well before applying anything you chose. Good luck.

Stan
 
It's been my finding that fiberglass just barely sticks to metal, and for a short time at best. It would definately break loose and trap moisture underneith, leading to paint bubblidge.
No matter WHAT filler you use, holes will invariably let through moisture and bubble the paint. If you aren't picky about tiny bubbles...you get to stop reading now ;).

If you're half descent at soldering, pick up some clear liquid flux from a leaded window glass supply store and use it with a brush to tin the backside and solder/lead the pin holes. You may have to cut some thin brass shimstock and make patches if the holes are large. The liquid flux makes soldering a DREAM on stuff like this.
You could do this with a hand propane torch on very low flame.

#2 Scrub your work both sides with vinegar or phosphoric acid to neutralize the flux.
#3 Primer and fill as suggested above.
 
Fibreglass based filler will work fine and it is waterproof.

I use stuff that has stainless steel strands through it.

Tap in you pinholes from the front and lay a good thick sheet of this filler inside for strength.

Then just use normal bondo to smooth the front side.
 
pooch said:
Fibreglass based filler will work fine and it is waterproof.

I use stuff that has stainless steel strands through it.

Tap in you pinholes from the front and lay a good thick sheet of this filler inside for strength.

Then just use normal bondo to smooth the front side.
Click to expand...


Sorry, but I doubt it 100% IF YOU LIVE IN A MOIST CLIMATE.
I have found the fiberglass filler in cans ALWAYS fails. It will make you feel great about what you've accomplished for a few weeks at best.
We used it in the bodyshop when people wanted a cheap fix and generally the car would be back in a week or a month with water blisters exactly where the filler was applied.
I've pounded in the rust and filled it, painted the back with resin...even tried sealing it with undercoat. It always bulges up under the paint after moisture gets in.
Fiberglass stands suck up the water through capilery action and it quickly becomes a big sponge. Boats must use a thick coat of gelcoat to seal the fiberglass so it doesn't absorb and go soggy.
They have always claimed on the can it is waterproof.
I've personally used Dynaglass, duraglass, tigerhair, kittyhair, long & strong, and probably a few others that killed some brain cells ;)
...each one failed.
Water absorbs through it like a sponge and in most cases it seperates from your metal with bumps and vibration combined with differentiating expansion & contraction rates and moisture absorpion of the metal.
*The only test I haven't given it was in a dry desert climate. It should be fine if the air is always dry.
In BC Canada we have plenty of precipitation and welding the metal solid is the only answer.
 
Craig Lewis said:
Sorry, but I doubt it 100% IF YOU LIVE IN A MOIST CLIMATE.
I have found the fiberglass filler in cans ALWAYS fails. It will make you feel great about what you've accomplished for a few weeks at best.
We used it in the bodyshop when people wanted a cheap fix and generally the car would be back in a week or a month with water blisters exactly where the filler was applied.
I've pounded in the rust and filled it, painted the back with resin...even tried sealing it with undercoat. It always bulges up under the paint after moisture gets in.
Fiberglass stands suck up the water through capilery action and it quickly becomes a big sponge. Boats must use a thick coat of gelcoat to seal the fiberglass so it doesn't absorb and go soggy.
They have always claimed on the can it is waterproof.
I've personally used Dynaglass, duraglass, tigerhair, kittyhair, long & strong, and probably a few others that killed some brain cells ;)
...each one failed.
Water absorbs through it like a sponge and in most cases it seperates from your metal with bumps and vibration combined with differentiating expansion & contraction rates and moisture absorpion of the metal.
*The only test I haven't given it was in a dry desert climate. It should be fine if the air is always dry.
In BC Canada we have plenty of precipitation and welding the metal solid is the only answer.
Click to expand...

I said the stuff I use has stainless steel strands in it.

And, I suppose, as I am a sandblaster, I would not put it over wire brushed rust.

I use in on boats too.

No problems.
 
You must log in or register to reply here.
Back
Top