More C3 chassis questions

[Michael L.]

I have a small area of rust on the front frame horn inner gusset. I'm thinking of just weldiing in a patch. I believe I can do it in a way that will make it unnoticible. Any thoughts? (see pic)

What is the best way to address the dents in the bottom of the frame from years of the car being jacked up? (see pics) There is some access to the other side of these areas (through the frame) and I was thinking of using some GENTLE heat to soften these areas up then trying to tap them out. Any thoughts?

Mike

[Joe L.]

Re: More C3 chassis questions

I have a small area of rust on the front frame horn inner gusset. I'm thinking of just weldiing in a patch. I believe I can do it in a way that will make it unnoticible. Any thoughts? (see pic)

What is the best way to address the dents in the bottom of the frame from years of the car being jacked up? (see pics) There is some access to the other side of these areas (through the frame) and I was thinking of using some GENTLE heat to soften these areas up then trying to tap them out. Any thoughts?

Mike

Mike-----


Are you saying what appears to be a hole in the frame horn is a rust-induced sort of thing? If so, I think I'd be concerned about other, more critical frame areas that might be so-affected. In any event, I'm sure it could be repaired as you describe and that'll be the end of it UNLESS it's just the "tip of the iceberg".

The dent in the rear crossmember could probably be best repaired by simply filling and sanding. It looks to be quite shallow to me and is going to be difficult to otherwise remove.

As far as the sheet steel panel on the bottom of the main front crossmember, Terry Fiala, a regular contributor to this board and I'm sure listed in the "members list", has developed a tool to remove just this sort of damage. You might try contacting him to get the details. However, from what I can see of it, your panel also appears to suffer from pitting corrosion. In that case, your best bet might be to obtain a new panel, remove the old one and weld the new one on. I think you can get this panel from Vette Products of Michigan.

[Chuck S.]

Re: More C3 chassis questions

I have a small area of rust on the front frame horn inner gusset. I'm thinking of just weldiing in a patch. I believe I can do it in a way that will make it unnoticible. Any thoughts? (see pic)

What is the best way to address the dents in the bottom of the frame from years of the car being jacked up? (see pics) There is some access to the other side of these areas (through the frame) and I was thinking of using some GENTLE heat to soften these areas up then trying to tap them out. Any thoughts?

Mike

Mike, it actually looks like a hole has been cut/punched through the front of frame rail to me...doesn't appear like rust damage, and it would be atypical at that location if it were; the rest of the frame would be toast.

Did a farmer own this vehicle and have to pull it out of the ditch a lot? What's the condition of the overlapping bracket that mounts the front cross member?...Did that part also get "holed"?

Little load is taken on the frame at that point; that area basically holds up the front end and reacts any front end impacts. If you can weld and finish a patch that's invisible, that's a good solution in my opinion.

I agree with Joe on simply grinding the frame surface with the shallow dents and pits, and smoothing them with body filler...I would not even attempt to "beat out" all those shallow dents; you'll probably end up making it worse.

I disagree with Joe on replacing the lower cover of the frame crossmember. Unless there is evidence of substantial rust damage on the interior, I would simply straighten as much of the jack damage as possible, then smooth the pits and the dent remaining with filler. Removing the crossmember cover would allow you to make a good inspection, but it's going to be a project. If you can weld like you say, maybe not that big of a deal for you. It goes without saying that filler thickness should not exceed product recommendations.

I haven't used the tool invented for that purpose, but I have "beat out" a big portion of cross member jack damage by working through the cross member using 3/4" copper pipe...you have to be careful not to mushroom the pipe end such that you can't get it back out. Using the tool would be preferred.

[Michael L.]

Re: More C3 chassis questions

Joe,

This is the only area of rust on the frame. The rest of the frame is in quite good shape, except for the pitting and dents. I know this is an unusual area for rust, I don't know why it started there.

I will definitely contact Terry to see about his tool. If I can get it close I'm not going to mess around with replacing it. There is going to be a fair amount of fill on most of the frame for the pits, I don't think a little more on the crossmember will kill me. It looks to me like replacing it would be a bear. Is this correct?

Thanks for the help,

Mike

[Chuck S.]

Re: More C3 chassis questions

Joe,

This is the only area of rust on the frame. The rest of the frame is in quite good shape, except for the pitting and dents. I know this is an unusual area for rust, I don't know why it started there...

Dude...that is NOT RUST DAMAGE!!!...There is no pitting or material loss immediately adjacent to the hole, and you can see where the edges of the hole have been deformed and then flattened by hammering.

At the bottom of hole, it even appears enough heat has been applied to melt the edges of the hole. It looks like the guy started out to torch a hole in the frame rail, got the hole through at the bottom, then opened the cherry metal up at the top with a hammer and punch, then beat it all flat again.

[William C.]

Re: More C3 chassis questions

According to the guy at Bair's who has done many many front crossmenber repairs, the tool is the most wonderful invention since sliced bread.

[Greg L.]

Re: More C3 chassis questions

I heated and "tapped" mine out with various "tapping" tools until I got it almost perfect and then finished with some metal reinforced body filler and now it looks perfect!

Then a few months later Terry invented his tool for doing this.....

You can do it like you say but I'll bet Terry's tool makes it a lot easier.

Oh and Chuck I know you Texas boys have never seen real rust(yes I envy you all) but that is rust on Mike's frame rail. That's what rust does when it starts BETWEEN two layers of steel. It rusts, rust expands and pushes the metal apart. That swelled area or lump you see on the lower side has been pushed out by the swelling rust. The reason that there is a hole there is because the rust broke through to the surface. Because this isn't really structural I would heat the infected area red hot with a torch to loosen the rust scale and then tap all around the area with a hammer to free the scale(it will be in chunks). Once this is all removed you can tap the swelled area back and weld in a piece where the hole is and fill it. No it won't be as strong as before but it should be strong enough. If you want it to be as strong as before I think you can buy that section in repop form.

[Chuck S.]

Re: More C3 chassis questions

...Chuck I know you Texas boys have never seen real rust(yes I envy you all) but that is rust on Mike's frame rail. That's what rust does when it starts BETWEEN two layers of steel. It rusts, rust expands and pushes the metal apart. That swelled area or lump you see on the lower side has been pushed out by the swelling rust...

Au contraire, my northern cowboy fren'...you said Texas was similar to Alberta with all the cows and oil. Wahl, I don't know about Alberta, partner, but Texas has plants that process that oil to make petrochemicals. I've spent a little time around the "black arts".

If you've never seen incorrectly spec'ed insulation stripped off refrigeration piping and fractionation towers after 30 years of freezing/thawing, and breathing in gulf coast 100 percent relative humidity, take it from me, I'VE SEEN RUST!!! I mean REAL RUST, not that piddlely little rash you get on car frames.

Metal inspectors in processing plants carry around those little pointed end hammers...when they inspect a vessel where steel has virtually turned to sheet rust that sloughs off when the insulation is removed, they find the deepest point of the corrosion and whale away with the pointed end of their hammers like demons possessed. The engineer looks on in anguish, because he knows if they knock a hole through that vessel wall, then there will be more tests to determine the extent of the repair, but a big section of the wall will have to be cut out and replaced with sound metal.

That frame picture is not high resolution...maybe that roll at the bottom IS rust trying to get out, but it looks like there is a "tear" at the 2 o'clock position, and bends at the 10 o'clock; how do you explain that cowboy?

[Mike G.]

Re: More C3 chassis questions

if you do need to replace a part on the frame, vette products of michigan sells any part of the frame you need.