Advice needed on cowl-fender repair areas and rust in welds |
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Advice needed on cowl-fender repair areas and rust in welds |
doug_b_928 |
May 18 2023, 10:48 AM
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#1
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Senior Member Group: Members Posts: 703 Joined: 17-January 13 From: Winnipeg Member No.: 15,382 Region Association: Canada |
After no progress in 2022 due to other time commitments I'm ready to get back to my restoration. Most of the rust repair on the middle and rear of the tub is done, but I still have the front end to do. I'm at a crossroads with respect to the cowl-quarter channels.
It's very difficult to see and even more difficult to get good pics but the right side channel has some spots where it has rusted through. Here are some pics: But the underside looks great to me. Here's pic of the underside which I cleaned up, rust treated, and epoxy primed several years ago. The left side fender-cowl channel is in better shape when looking down into it. Here is a pic: I removed most of the seam sealer from the underside but still need to clean it up. As shown in the pic below, there is a spot of rust but it does not look like it has rusted through, so I expect this side to clean up as nicely as the right side. So, question #1 is how to deal with these areas. There aren't many threads that deal with their repair but having studied the ones I could find I think I have a good sense of how the two pieces are welded together. It looks like it might be difficult to remove the spot welds in the door area. I believe I can do it but I'm wondering if wire wheeling, treating with metal prep, epoxy priming and then seam sealing might be what's best in this area. Obviously best is always to cut it out and get rid of any sign weakened metal but then getting the panel to look as good after the repair might be a challenge and since this location is kind of buried maybe it's better to leave the nice lines on top and treat it. On the other hand, if it's going to be an issue in the future then I'd rather cut it out and repair now. So this is the conundrum. What say the brain trust? The top side of the cowl is in nice shape and the channel for the windshield has some pitting but not perforation. I still need to take a wire wheel to the windshield channel. Here are some pics: Unrelatedly, one benefit of taking forever to do the rust repair is one gets a chance to see where rust wants to rear its ugly head again. There are 4 spots where I can see some rust on the epoxy primer. Two of them are on the left suspension console where I did the 'weld little rust areas with the mig' techniqe. Here are pics of those: And the other two are seams where new metal was welded to old. One is on the rear trunk floor crossmember and the other is below the right rear tail light. So, Is this a matter of some rust mixed in with the weld or is that there was still rust behind the area that needs to be dealt with? Attached image(s) |
Montreal914 |
May 23 2023, 09:52 PM
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#2
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Senior Member Group: Members Posts: 1,675 Joined: 8-August 10 From: Claremont, CA Member No.: 12,023 Region Association: Southern California |
This is a pretty complex area. From one of your picture my concern is here:
Where the arrows are pointing the metal is bulging. Why is that? Well that is because there is rust in between the 2 layers there and it is pushing the metal out yet the spot welds keep this together. So the question is how to go in there. (IMG:style_emoticons/default/idea.gif) The green circle you have in mgphoto's picture is near the "upside down "J" (for lack of better description) joint between the inner layer of the fender (refer to the OEM fender picture), and the area in front of the door. That would be a real pain to drill the spot welds there. So your suggestion of the horizontal cut above it and butt weld seems like a possible solution. Edit: I guess using the narrow belt sander you might be able to reach the spot welds but you will have to grind the two fender layers to get to the spot welds that are bonding to the cowl. I would do the other cuts first, then maybe you will be able to pull out the fender and rip at the cowl. It will be bad anyway and you will need to repair it. The fender might not be too bad. The weakest link will let go first. So is there a gain to want to use the belt sander? In the end it will damage pretty badly that area. (IMG:style_emoticons/default/sad.gif) |
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