The Dreaded Bondo Worm...

[anlauto]

I took a really nice clean set of doors to Techno-Strip to have them stripped clean....I knew one had bondo worms but had no idea is was to this extent...

So my question is: Back in the day, why did they not weld these holes up after pulling out the dent ? Was it just plain laziness ? or did they not want the heat on the panel ?

[anlauto]

You can also see rivets for body side V5X that have been ground off.

[71vert340]

 Time was money to a body shop collecting insurance. They could Bondo over it and be sanding in an hour vs the time to weld it up.
Terry

[6bblgt]

back in the day - the typical garage mechanic didn't have the tools that the average automobile enthusiast has in their garage today

a can of "bondo" & a slide hammer dent puller were cheap compared to the cost of the tools necessary to weld (or an acetylene torch & coat hanger) - air compressors and the ability to paint a panel or complete car were not in the average home garage

cheap portable 110V or 220V wire feed welders did not exist

[JS29]

How long ago was the repair made? back in the day MIG welders were few and far between. plus the theory was the holes gave the filler something to grip and hold. I don't remember when fiberglass fillers came around, to the best of my knowledge it was the early 1980's.                                                                                                   BONDO is a brand name. It's body filler   

[anlauto]

Check this weird method of a patch....also cleverly hidden....Same 71 Challenger but this fender was not originally on the car....

If it's spot welded, how did they get to the backside with the fender reinforcement right there....and the edges of the patch are wide open to moisture, not too mention the open holes 

[JS29]

Spot welders used two electrodes, they did not go to the back side like a clamp and do one spot weld at a time. they did two at a time.   

[YellowThumper]

Thread is noting the "back in the day" fix. However, what I see with that type weld is usage if a tig. Add heat to burn thru just enough to bond them without usage of filler rod.

[jimynick]

Spot welders used two electrodes, they did not go to the back side like a clamp and do one spot weld at a time. they did two at a time.   

Yep and what you're seeing is when buddy cranked up the amperage and burned through, but couldn't be bothered to do anything else but mud 'er up. The spot welders came out in the early 70's and the fibreglass fillers in the mid to late 70's. The FG filler- we used to use a brand called "Kitty Hair" were the cat's ass- pun intended- as they were waterproof and had better adhesion than bondo- I know it's a name brand- did. As for the slide hammer usage, when you were a flat rate bodyman, you sure as hell didn't weld up their holes! The heat would warp the bejeezus out of the panel and then there was the fire hazard.  Remember, these were everyday cars then and their life expectancy ran about 5-7 years and they were paying me $2.00hr in '71. Now where did I lay my slidehammer....? 

[71vert340]

 So Alan, do you repair those parts properly by welding or go with new aftermarket sheet metal? Just curious. Terry

[anlauto]

So Alan, do you repair those parts properly by welding or go with new aftermarket sheet metal? Just curious. Terry

On this car those panels will be repaired by welding.

[RUNCHARGER]

That looks like the right choice here.

[Shane Kelley]

The other thought process for leaving the holes was to help the filler hang on to the panel. When it squeezed through the panel that anchored the filler. I know it sounds crazy now but that's what they believed. You also have to remember these types of repairs hadn't been going on for several years so nobody had seen what happens as a result of time and mother nature. We all have the luxury of hindsight now and see what leads to failure. You have to also remember there was no training for quality proper repair processes. It was a different time.

[YellowThumper]

The other thought process for leaving the holes was to help the filler hang on to the panel. When it squeezed through the panel that anchored the filler. I know it sounds crazy now but that's what they believed. You also have to remember these types of repairs hadn't been going on for several years so nobody had seen what happens as a result of time and mother nature. We all have the luxury of hindsight now and see what leads to failure. You have to also remember there was no training for quality proper repair processes. It was a different time.

Yes, holes were for the added strength to hold on. IIRC the early years of Bondo the adhesion was not what it is today. Or to rephrase it. The flexibility we have now was not there. Separation from panels due to differing expansion rates. I knew someone who actually drilled extra holes just for that. Not saying it is or was correct. But it was done.

[7E-Bodies]

@6bblgt you are quite correct.  I worked in autobody in the early 80s. We had an outstanding old body man and he always used brazing rod and oxy/ace. A slide hammer was always within reach. A mig was untouchable on a body shop budget back then. Now I have everything in my personal hobby shop. Times have changed.