Big Fish

Okay, I tried this in the C3 section, plenty of hits, but not much response. Can anyone advise me of the procedure to replace the rocker channels? Mine are rusted out on both sides, large holes nearly the size of baseballs where the body mounts were (position 2 & 3). I need to know if I need to completely remove the body from the birdcage, or is there a shortcut here? :crazy:

67HEAVEN

Big Fish,

I've never gone as far as replacing portions of the bird cage, but to replace the rocker channels, I think you'll have no choice but to lift the body first.

Next, you'll be in to fiberglass, metal cutting and welding. I think you have a major job on your hands......one that will no doubt grow into a body-off resto. You know....well since I've gone this far-itis. :jester

I hope someone with specific experience in rocker channel replacements chimes in.

JmpnJckFlsh

Not too surprising, and it's doubtful you will get much help here either; this repair is something must have been be done by the person doing the talking. Creative speculation ends on this one.

I don't know about taking the body completely off the birdcage... each individual panel is cemented to the birdcage. You may have to remove or selectively loosen some panels. One thing is for sure; there are no shortcuts. The absolute best authority on this repair is Ron DeVries, but he hasn't posted in awhile.

Say, Macster, email the Ronster, and tell him that there is a feller here that REALLY needs help with something that only he knows. :D

Mac

Will do!

Bigfish, although I wasn't there when Ron replaced the bottom sills of my birdcage, I saw the job before and after. The sills themselves are available NOS but not cheap. If you haven't already purchased an AIM (Assembly Instruction Manual), it's time to do so.

Here's a diagram of the birdcage and picture of the job....

Big Fish

Chuck and Mac, thanks for your replies. You have re-inforced my original thoughts on this disaster. I pretty much wanted to make sure nefore I started tearing into it. The pictures are almost identical to what I've got going on here. Looks like the bottom 2 are part of the completed repair? :cheers:

Mike Ward

If you're looking for a beentheredonethatgottheTshirt opinion, yes you have to pull the body. Theoretically, you can do a heart transplant via an existing bodily orifice, but it's much more practical to make a more direct path.

You may also find that the bottoms of your pillar posts are damaged, but remember, everything is fixable.

I have pictures of my iron oxide warrior before salvation, will post them one day. :cheers:

Guest

That reminds me what the D.C. Medical Examiner said to the press a few weeks ago.......The best available health assessment around today is an autopsy. :D

Mac

Yep, the left is the insert in place, the right (with vice-grips) has the sills in just prior to welding. I sent RonD an e-mail; no reply as yet but it is the long weekend, so he may be out of town.

Big Fish

Mac. if I'm reading the pictures correctly, it looks like the inserts and the channel were replaced without total removal of the body. I think what I'm seeing here is the door and rear quarter are still in place? :confused:

JmpnJckFlsh

The body is off the frame.

Normally, the bird cage rails fit right over the frame with maybe an inch or less of clearance. In the right bottom picture, the frame would be right where the vise grips are if the frame were there. You could not get the vise grips in that position if the body were on the frame.

Starting at the top left, number the pictures from 1-8 with odd numbered pictures in the left column, and even numbered pictures in the right column. Pictures 1-2 and 5-6 show views not normally seen with the body on the frame. In pictures 1-2, it is clear the rust-eaten sill rails have already been "demo'ed".

What you are looking at in pictures 1-2 is the front of the bird cage, items 5, 6 (see "birdcage" diagram above) on the right and left side respectively. Pictures 5-6 are the rear of the birdcage showing item 2. Pictures 7, 8 show the rear of the birdcage, item 2, with item 12 already replaced on each side, and the visible birdcage painted. Picture 8 shows the new sill rail clamped in place and ready for welding. It appears to me that NO fiberglass panels have been disturbed, BUT it does appear that the bulkheads on the front of the rear wheel wells had to be cut out. This repair will require some very careful welding.

Earlier, you asked about removing the body from the "birdcage"...that can't be done without destroying the body since the birdcage is an integral part of the fiberglass body. For this repair, the body WILL have to be removed from the chassis. But, not to worry, removing the body from the chassis will be "child's play" compared to the rest of this repair.

Really nice pictures, Mac. Too bad you and Ronster aren't NCRS members...You could write an article for The Corvette Restorer. :D :D :D

(There, maybe I got it right this time :D :D :D :D )





[Modified by Chuck Sangerhausen, 9:31 AM 9/2/2002]

Mac

The body has been taken off the chassis frame, but the birdcage cannot be removed. As Chuck said, it's glued in solid. This repair would be next to impossible without having the body on a hoist because doing the welds lying on your back would be hazardous and extremely difficult.

Chuck's description of the pictures is accurate. The difference in my car, once repaired, was incredible. These bodymounts support the passenger's area, so you can imagine what it was like before.... and after. In my case, the sill (part #4 on the diagram) and the rear inserts (part #12 on the diagram) were rusted beyond redemption. How bad? Well, a picture is worth 1000 words.

Big Fish

Chuck and Mac, you guys are terrific! Your explanation of the pictures makes everything clear now. I was really depressed at the thought of having to remove the body from the bird cage, couldn't really see how it could be done without cutting it all apart. Now I can clearly understand what needs to be done. I already have the body off the frame, I have completely restored the frame and all the mechanical components to like new condition, was getting ready to detail the bottom of the body when I found this problem. I guess after all that I've been through on this car already, this repair won't be nearly as bad as I first thought. I can see the need for cutting out the inner fender forward of the rear wheels, I'm thinking about removing the front clip as well, think I have some seams there that have come loose. Did you have the front clip off to perform the channel replacement? :cheers:

JmpnJckFlsh

I can't see how the sill rail replacement would require removal of the front clip, and I would not remove it unless absolutely necessary. Which seams are broken? Almost all the bonds can be repaired with the clip on the body.

Only if the front clip bonds to the bird cage were broken completely would I consider removing the front clip. Proper realignment of the front end to the rest of the body will be difficult, and I don't see how it can done without remounting the body to the (freshly restored) chassis using the original shim thicknesses.

My front clip has clearance between the plenum and the birdcage where the bonding adhesive has broken and fallen out. Since the bond is still solid, I plan to clean out any loose material, rough up the opposite surfaces, and fill the gap with fresh bonding adhesive. The bonds between the front fenders and inner fenders are also broken. The tricky part of rebonding the inner fenders is that you have to make sure that the fenders and hood top surfaces match.

Mac

The front end was not removed, for all the reasons Chuck gave. It's not necessary for the repair and it's not desirable; it's a major undertaking.

It's not unusual to get some minor cracking in the bonding strips on the fenders close to the firewall when the body is off frame, especially if you haven't properly supported the front end (the voice of experience speaking) but that's an easy repair compared to realigning the front clip.

Big Fish

Makes sense to me then to try it with the clip intact. I really do appreciate all the help you guys have been, I ordered channels and inserts today, I'll be sure to post here as to how things are going. :cheers:

Mike Ward

Don't want to rain on your parade, but you may want to do some exploratory examinations and make sure your pillars posts and windshield frame are in acceptable condition. The main reason for rocker channel rot is water leaking behind the windshield, down the inside of the pillar posts and along the rockers. If your car was driven in salt this effect is much worse.

Mine were in much worse condition than Mac's and the entire birdcage needed to be changed. It is also common for the rot to have progress up the rear hoop of the birdcage.

Ron D

Hi Guys, thanks for the Kudos :) Been awhile but I have been alot busy. work work work :( Big Fish... You lucky devil you :D I hope you love your car bwahahahaa !! First off you dont need to take your front clip off as the other guys have also said. If you look at I think it was the third row of pics in Macs post you'll see that I did cut the rear inner fender inserts out on both sides. I did not remove them completely if you look close as it is easier to glass them back in if your bonding to flat surfaces. I used a dremel with a cut off wheel to cut the glass...nice and clean cuts and not wide either. As for the sill removal...don't know if you have pulled the old ones out yet of not but you will need to clean the old ones up as best as you can to be able to see the old spot welds ( re the assembly manuals weld patterns) and then drill them out so as to retain all the original backing you can if any is left and clean these surfaces as best as you can. When you get your new sills you will need to drill 3/8 holes where the original welds were in your new sills so you can plug (fill holes with wire feed) weld. You will also need to pre drill the rivet holes that hold the sill to the body on the inside ( use SS rivets as they are stronger and will not corrode ever). So I dont have to wrtie a small novel here can you tell me a little more about what is behind your old sills and shed a little light on what is still good. Are your lower A and B pillars still in good shape? Mike brought up a good point about water coming in from the top. You will also want to look at where your body gaskets (L shaped foam) just in front of # 2 mounts. The have a habbit of acting like and sponge and wrotting out your frame where they sit. Anyway..give me some info and I will help where I can.

FYI 73 spots website also has my description of the entire process of what I did on Mac's car.

Big Fish

Ron, it's nice to hear from you. These guys sure think a lot of you, and after viewing some of your work on that 73 in your gallery I can see you know your stuff allright! From what I can see and feel of the pillars, they seem pretty solid. You have a terrific idea about drilling out those old spot welds, my guess is the channels should drop right out. I have triangle shaped panels on this 75 on both forward sides of the rear wheel wells. I was thinking about carefully removing the bonds on those which should give enough room to get in there? The gaskets you are referring to, are they the heat shield gaskets that lay between the frame and the body? Would you recommend I leave them out, even though this car will probably never see salt again? I've already gone over the entire frame, thin steel was removed and new welded in place. Then the frame was sand blasted and powder coated. Frame is 100% done now, just hit this little snag. I just ordered channels which come with inserts (front and rear) and a sleeve? not sure what that is, suppose I'll find out when it arrives. Hopefully the pillars are as good as they look, no way my channels are as rusted as the ones shown in your gallery, maybe that's a good sign. I do have access to a sheet metal shop where I can fabricate repair pieces as heavy as 12 gauge if needed. As long as I'm thinking about it, what's the best way to temporarily support the body with the channels removed? I was thinking about supporting it using wood to spread out the weight over a large area of the floor pan? I appreciate your help very much.

Ron D

These guys helped me out, above and beyond when I had the questions...its what this hobby is all about :) Drilling is the only way I feel you can pull the old sills out and not make a make work project for your self. As for removing the rear inner fender panels... pull your old sills out first and then see if the lower B pillars are in good enough condition..if so you may be able to leave the inner fender panels in place. If you do end up having to pull them I would recommend cutting them like I did in the pictures...the adhesive they used by the factory to bond them to the fenders ( the outside behind the doors) can be extremely hard to remove without stressing the exterior body panels and may crack your paint and fiberglass. The gaskets..I left them out on Mac's car, basically an up to you sort of thing. They are dirt and water magnets in my eyes and if heat is what they were intended to help divert...well we all now just how well they worked heehee :) Supporting the car: Jack stands under the rear storage compartments with wood 2x10's on top and and small piece of 1x4 on top of the one under the battery (you'll see). Stands or blocks under the front of the foot wells running parallel to the sills to take that wieght and the prop up the nose really well as Mac noted or yah get a few cracks ( we won't talk about trailering cars without a frame hey Macster :D) in your bonding strips in front of the doors. Just a foot note but when you get your new sills run a tap thru the rocker mount screw holes prior to the install...easy to fix while they are out if need be, if you catch my drift. Time for bed. :seeya

Big Fish

I thought I would give everyone an updtae on this project. Today I removed the channel from the driver's side, the side I felt was the worst. This went a lot better than I expected, mainly thanks to all the support and guidance everyone here has given me. The posts are in great shape, the inserts were trashed, and also removed. I didn't get a notice of possible back order on the replacement parts, so I expect to remove the other channel tomorrow, then possibly this weekend put it all back together. The one concern I have at this point is how to weld the inserts back in. Should I just do the best I can around the bottom, then grind iit smooth? Possibly there is a better way? The front ones I might be able to get a little weld on the top edges? I am planning to drill holes in the channels to allow welds to the posts.