Fibreglass Patch
 

Hi guys

My 1sy bondo fibreglass patch didnt set up right.
Dont think I got my mixture ratios correct - its tacky and not hard.

Not sure if can be fixed. Or start over ??

I tried using heat to reactivate it - but that seemed to make it softer with the heat .... and then it setup much the same.

:waah:

Re: Fibreglass Patch
 

it should have setup pretty quick...if it hasn't then youll have to remove it and start over...

Re: Fibreglass Patch
 

dangit ....... somehow I knew that would be the answer

not sure what I did wrong ...... but I did half ass measure ..... so must be it.

Re: Fibreglass Patch
 

First step: Take it all off as there's nothing you can do to reactivate it.
Second step: Throw the remaining product away unless you are working on a boat or a Corvette or a Cameo.

Re: Fibreglass Patch
 

Well said.

Re: Fibreglass Patch
 

Lol

And use what instead ?

This is to cover-up pinholes and small holes where I can't really weld without blowthrough as so thin ....

Re: Fibreglass Patch
 

where is the area your trying to fix?...remove and replace is the best way to fix.....
if you have access to the backside you can use a copper backer and weld up the holes...metal needs to be clean to do this .....

Re: Fibreglass Patch
 

If the metal is very thin with holes, any kind of filler you put on top will not fix it and will fail to adhere in a very short time because moisture will continue to invade and more rust will ensue which will cause any repair material to crack and bubble and fall off... even fiberglass.
I'm afraid you don't have any options but to replace the metal with good steel and do a proper repair.
Anything less than this approach will be a complete waste of materials and your time.

Re: Fibreglass Patch
 

HI
Yep I used the copper trick on most of teh welds.
Just stuff where its too tight to get a copper piece tight against the metal on backside.

For the doorjam pillar support area down to the actual step on passenger side

Re: Fibreglass Patch
 

Its 98% metal patches in.
Pic here.

https://i.imgur.com/AsQnAQ0l.jpg

Re: Fibreglass Patch
 

Turn your welder down, then real quick tacks to get them filled in. Move around and take breaks to keep the heat down in the metal.

Then get a quality epoxy primer and brush it over your seams to get any unseen pin holes.

Re: Fibreglass Patch
 

Whats a good epoxy primer thats not crazy $$

https://www.eastwood.com/eastwood-gr...4aAlwTEALw_wcB

?

Re: Fibreglass Patch
 

PPG Omni MP170(gray), MP171(white), MP172(black)

http://us.ppgrefinish.com/PPG-Refini...-Refinish/Omni

Re: Fibreglass Patch
 

Any and every epoxy primer does the same job. Just be sure you are buying 2k epoxy primer and some other epoxy enriched or other misnomer.