Hi guys - looking for some ideas/coaching here.

This is the passenger inner fender where the hood assembly attaches. The only metal that can't be saved is immediately under the hood attachment plate.

Specifically, here is the rot that needs to be dealt with;



I really want to avoid replacing the whole inner fender since this is the only area with rot.

I was wondering if it could treat the existing metal with a rust converter, leave it in place, and then weld a patch over the area to strengthen the area and hood attachment area. Something like this;



I know this isn't a "proper" repair, but this car will never be more than a driver and that is my intended purpose for her.

That part of the inner fender has some compound curves, so actually making the match will be a challenge, but I'm thinking it beats removing and then trying to align a whole inner fender.

What do you think guys?

Is that "plate" removeable or is it spot welded to the inner fender ? I was thinking that there may be some hidden rust under it if it was a removeable backing plate.
Otherwise, something along those lines you propose sounds like a reasonable plan to me.
There might be reason to grind some of the rusty metal away before you weld.

Hi Ken - I'm not sure if it is removable or not. I'd better know that before I weld it in place, eh? LOL.

Anyone know for sure about that area being removable? it looks like part of the inner fender from the Moss pictures but I'm not positive;



Here is a quick patch I worked up - it's not fully fitted to the contours of the area yet but it's fairly close.




I've got other areas to repair in there for sure, but I think this would put enough strength back in there so that it would stop the area from distorting under load.

Yeah, and if you have any doubt about needing to strengthen the area, you could run another bolt and nut thru some of the good metal.

My only commment is that you'll burn the rust converter when you weld it on, thus negating it's value.

I personally use a weld through coating, which is a spray paint with lots of zinc in it.

Or you could pay about 1/4 the price and buy galvanizing paint, which is spray paint with lots of zinc in it.

You might also want to bring your repair around the right side of the hood mount and incorporate the rusty spot over there in the same patch.

Other than that. looks good

What you're proposing to do is almost exactly the kind of repair a body shop did for me some 20 years ago on the inner fender of a '67 Volvo 144, around the hood hinge mounting points! This was and still is a very, very good body shop, and their repair literally outlasted the rest of the car.

Hi Andy - thanks for the note. That is encouraging to hear.

Hi Steve - I was planning on using rust converter on the broader surface, then wire brushing back where the welds would be and hitting all of this with weld-through primer. Here is what I typically use.



So I'd have a layer of rust converter and weld through except for the area immediately to be welded which would "just" be weld through primer.

I don't think that the weld through primer would stop the existing spots from further rusting, would it? Don't you need to convert the remaining rust to ferric phosphate?

I would want to have a look at the other side of the panel to see if any rust has come through. I would also have a go at removing that strengthening plate to see if it will unbolt.
My concern would be that the likelihood is that the rust has started because of moisture being trapped between the inner wing and that plate. So, it is likely that there will be more serious rust under there. By plating as you suggest, you will not be adding to the support for the bonnet hinge, just surrounding some weak metal.
If the plate does come off, you will be able to do a permanent repair and then treat for rust with Waxoyl or similar between the plate and inner wing.

Should have said that this is advice for a car living in damp Scotland and it may be considered over the top for a Californian car!!!! I have known a few cars here where that panel has rusted completely through and the bonnet has become detached at a front corner!!!

Hi Nick - good to hear from you. I think it comes down to if that plate in question comes off. So far it appears to be spot welded in place. If it comes off them completely agree, if not then....

And while I'm in SoCal, rust always finds a way if allowed!

The plate in question is indeed welded to the the inner fender. Do you have the fender and headlight bucket off the car? Also did you remove the bonnet to see what it's like on the other side? If you are going to remove the bonnet and hinge, I would remove them with the hinge attached to the bonnet. Do make some marks to help realign the bonnet when the repair is done. Without knowing the extent of the rust behind the hinge it's hard to make a call on how to do the repair. Unfortunatly I think the bonnet must be removed to find out your next step. I would also try to make all the repairs on the outside of the inner fender so you will see less repair when the bonnet is up. How are your welding skills? Any repair will damage the paint on both sides. I think the removal of all the rusted metal is your best bet, and then fit in a new piece. Show some pics if you remove the bonnet from both sides.

Just to let you know I do tend to go a bit overboard on repairs. A patch may be good enough to make it strong enough so the hinge won't sag, or flex.

Hi Tdskip,

What's the metal like on the other side of the mounting plate? If it looks solid then you are probably fine with what you are planning to do. If it's badly rusted you can get some sheet metal and bang it into shape and weld it (flange weld and plug weld combined) to cover the back side of the mounting plate for the hinge. It's not the best thing way to repair, but if you give sufficient overlap then the repair will be plenty strong, and last as long a you own the car. It will at least keep you from having to replace the apron which is a big job.

I am working in a simmilar area on my car right now.

Cheers

i would sand blast it to remove 100% of the rust that you can get to and use the weld primer they mentioned, do your welding then blast it again and use some epoxy primer on the area and cover with some undercoating real good just tape off the bolt threads, your patch looks like it would work fine. if the rust is worse than it looks after you blast it maybe make one like this.

Be careful welding on galvanized metal since it gives off gases that are poisonous to us humans, not sure about the weld through coatings.

Sorry these are a little blurry, but here is what the area front/back looks like after moving the hood support around to gain better access.





So what do you think guys - patch the front and back?

Thanks!

Cut the rusty area out and install the patch. It will then be patched front AND back.

Well, I got the front side patch welded in.

I still need to clean up and dress these welds, but seems to be solid. I'm not the best at thin sheet metal so I tend to put more metal down than I need and then grind any excess away.

Did you cut out the rusted metal , or did you just put a patch over the old. Either way it should hold just fine. 3/4 of the metal around the bracket was as good as new

Hi Keith! I did cut the rot out first and used rust converter on the area, then ground back to clean metal on the areas that would be taking welds and then primed that with weld-through primer.

I have some touch up to do on those welds, missed a couple of spots, but the mounting point is noticeably more solid now.