As some point in the life of my 65 conv - before I bought it - the left side half-shaft U-joint let go at the pumpkin and turned itself into a rotary sledgehammer underneath my car.

It didn't tear it up too bad (could have been much worse) but it did damage the storage compartment pretty good behind the drivers seat. Somebody did a sloppy repair job with fiberglass mat and resin (no doubt purchased at Wal-Mart) and now that Bubba Repair Job has failed and needs to be redone the right way.

What is the recommended proceedure? The piece that connects the two storage compartments has a good crack in it, and the passenger-side compartment is busted up a little too. When I have a passenger, the floor sags and you can hear the floor hitting the u joint in front of the differential.

Do I cut the whole thing out? Try a different type of repair? I have a 4 post life in my garage and will have some time this winter to do it right.

Does anybody make an aftermarket floor panel? This can't be the first time that a Ujoint has let go and busted up a Midyear floor, right? Any suggestions or stories of prior attempts at the same repair would be appreciated.

On the bright side - at least my car has enough power to bust a U joint! :rolleyes: (Trying to find a bright side in this)

Thanks & I ALWAYS wave. Always. :seeya

 

I inherited the exact same problem with my car, except it was on the passenger side. Nice big hole with a sloppy repair. I don't know of a replacement piece for these although if you have a Corvette salvage yard around close you might cut one out of a donar car. I ground the old repairs off of mine and using some pieces of fiberglass left over from past repairs, cut them roughly to fit in some areas and made forms of heavy cardboard and duct tape to finish up the rest of the area. I then laid fiberglass over it on the outside until I had it built up pretty close to the original contours. Then I had to do some grinding inside and finish up with some mat to smooth it out. Lots of sanding, a little filler and some blocking and it looked pretty good. The main problem is that the underside of Corvettes were natural fiberglass and unpainted the repair will be apparent. I went ahead and sprayed the underside of my car with a thin coat of semi-gloss. Not exactly stock but it doesn't look out of place, everything looks good and it cleans up well. It's also held up good - real solid. Good luck :steering:

 

I clicked on new topic instead of reply. Read what I meant to send you under (colored resin helps). :thumbs:

 

I'm not sure you want to cut out any of the storage boxes or floor area. You can make a real nice repair and make it stronger with what you have there. You would have to grind out Bubba's crap and prep all the areas around the cracks, holes, etc. You want to do a dish grind around the hole or crack. Your shooting for approx 2" out from the edges of the hole. Sometimes more, sometimes less, depending on the size of hole or crack. You want a taper grind starting at the outer area of that 2"s and do a dish grind down to the edge of the hole or crack. You want that edge of the hole as thin as paper. Remember on a crack though, or should I say a stress crack, you want to relieve it first. Take your jig saw and cut the center of the crack, the full length of the crack or center of the tare. ( Sometimes all you need is to use one of the carbide milling bits in your Dremel to relieve the stress. Remember, whatever concaved area you make, it must have glass laid back in it, with all air removed between layers. Glass well have a mind of its own sometimes and only lay a certain way, especially over sharp outside bends and corners. Experiment with some pieces of glass first.) Then do the same dish grind to it's edges. Masking tape works good behind holes and cracks to keep your glass in shape, again depending on the size of the hole. You only do this to ONE side at a time. Let your glass kick good, overnight, again this all depends on how hot you mixed it and the big one of course is temp. Then after cure, you do the other side the same way. You do a dish grind starting out at the most outer area and dish down to the edge of your hole, JUST to the new glass you laid on the other side. Your looking to get 2 to 3 layers of 1 1/2 ounce fiberglass into these dish areas. Besure and use mat glass and nothing else. Some areas are going to be very hard to get a die grinder with a 3'' or even a 2'' sanding disk into it . I would suggest investing in a Dremel or like tool. It well be your right hand around glass and metal too. You can dish grind some mighty tight areas and rough em up with this tool. The area your talking about between storage buckets, especially where the tunnel passes through it, seems to be a weak area in many of these cars I've seen. I'm talking about the area with the four glass ribs molded into the glass for some added strength. The metal luggage stop behind the seats rivets to this area all the way across. It also helps to spread the load across, at least until the rivet holes that hold the stop become to big for the rivets. What I did on this car was to add more glass to these ribs especially next to the tunnel area, I mean spread the glass out a little too. I did it under as well as inside the car. I also had to dish grind all the holes holding the luggage stop on, glass em, re-drill em to start over again for a firm fitting stop.
I would also suggest buying your resin from a good auto paint store or from somebody like Eckler's. Some guys like going to boat places to buy their resins, whatever works for you. Also if this area has a bad sag in it, you might want to block it up level or close to, before you start glassing. Hope some of this info helps.
Craig :)
BTW, You might find an area where you won't get much of a dish grind because of room. If this area isn't going to be seen or isn't going to have something else fitting in a precision way next to it or on it, don't be afraid to build this area up with glass. You can still lay glass in a neat and clean pattern, just don't forget to rough up the area real good.



[Modified by Cmacsvette, 5:11 PM 8/22/2003]

 

:iagree: Ditto. Did all of this too but didn't go into as much detail in my post. Good information to follow. :steering:

 

Craig,

Thanks to your (and the others) for taking the time to type out such nice detailed instructions.

I was a little afraid to just cut a big piece of my floorpan out and replace it - I like the repair route much better- especially since no one makes the replacement piece :confused: I figured there would be more demand for it.

I have a good dremel tool and a 4 post lift and plenty of time when the snow flies. I have lots of air and electric sanders as well.

I may need a little more info on the bracing for the arched piece that connects to two storage trays. Can I buy this bracing or will I have to re-create it? I don't see any bracing there anymore. Bubba must have cut it out. That is why I get the floor-sag with the passenger I bet.

This forum is the best! Hopefully I can be as much help to others as others have been to me.... :cheers:

 

One other thing - I want to use fiberglass MAT and not the fiberglass CLOTH correct? The cloth is that messy white crap they sell at Pep Boys, Auto Zone, Sears, etc. I have never had good luck with that stuff in the past.

 

Well, I hate to be the one to put the screws to your balloon, but that messy white crap is mat type glass and thats the kind you want. :cry :cry :yesnod: Trust me, it's not that hard to work with at all. I swear, I think where some people get in trouble with fiberglassing is not the glass itself, but the RESIN. They think they need a lot of it and they don't. In fact after you lay the glass, you want to wick the extra resin out of the patch. It doesn't need to stay there and run all over the joint. In fact it doesn't even have any strength in itself, or at least the kind of strength your needing in these repairs. The strength your looking for is a result of preping the surface, laying the glass, removing air between layers, along with the PROPER amount of resin.

The cloth type is the weave type, criss cross, nice and smooth, you could almost use it for a blanket. :jester
I would still go to your auto paint store or boat repair shop and try to get your nice messy white crap there. :lol: The reason I say there, is because most likely, you well be able to get the" heavier" glass. Most likely, but I'm not sure, the stores you mentioned, may have the "lighter" weight glass, check em out. Eckler's also sells 1 1/2 ounce glass. I also believe their resin is a very good product too.
Now you also said the " arched area between the two storage trays" I presume you mean the tunnel area, where it expands over the top of the pumpkin, correct? The area I was speaking of earlier was the area just forward of the pumpkin arch. It's the slot that runs the full length, just in front of the storage buckets. That slot also incorporates those 4 molded ribs. (stiffeners). Where the tunnel expands from this slot rearward, over the pumpkin, there was no bracing, just a nice large smooth arch. Yes, I would plan to re-create whatever is missing. Yes, you can reform any of these areas and make them strong, as well as pleasant to look at too. It would also be nice if you could post some pics for some more input, but I bet it's bad timing, with summer and all. :steering: Some of these repairs you need to make, may have stuff in the way, like, a pumpkin, half shafts, a driveline, etc., and then you have the interior to deal with. You really need to repair both sides of the glass to do it right. Now if you want, I can take a pic of my 7 car this weekend & post it. All the areas I've been speaking of are wide open to see. Anyway thats my 7 1/2 cents, hope some of it helps.
Craig :thumbs:
BTW, DansYellow66 mentioned it earlier about the natural finish under these cars, he's right. You can have white, gray or black glass and you are still going to have that translucent look in your repairs where you leave em natural. It's still strong, it just doesn't have the tint. Also, vettnut posted a topic "Colored resin helps" for us too.


[Modified by Cmacsvette, 11:17 AM 8/23/2003]

 

NF, My biggest damage was at the trans end. It was grease soaked for years and I had to cut back quite a ways to get to clean glass. If your u-joints have slung grease on the glass make sure it's clean! The grease travels up the frayed ends of the fibers. There has been a couple of posts on the sagging issue. Most have placed rubber strips under the cross member to add support. All but the end rivets were pulled out on my luggage stop. I just bolted it back together (It's a driver) and it worked fine for me. Also make sure your diff bushing is in good shape. Wear disposable latex or vinyl gloves while doing the glass!

 

Your 1965 floorpan is either "off white" or "grey" composite. I made a similar repair to my 1965 floorpan, and I bought the resin, already tinted, from Corvette Image. I was able to adjust the shade using ordinary "Tints All", which you can buy in a paint store. My repair is "undetectable", but takes a lot of hand laying, sanding, polishing, cursing, drinking, sticky hands, tool throwing......... And, yes, you don't want the woven glass cloth, you want the messy glass mat. Good luck, and take your time.

Joe

 

If you have gaps or open areas (holes) in the glass after you remove and clean back from the old repair the most difficult process is to get the shape back and to get support for the new glass MAT material. A way to make the material used to fill in the holes and shape parts is as follows:
Take one layer of mat material and lay it out over wax paper on a flat surfac....if you want a flat part. Work the resin into the material and let cure for approximately 1 hour. This will make a thin flat sheet of glass that is still pliable and can be cut with scissors. Cut the material to shape and bond into the cut back area of glass on the vette. Let cure for several hours and continue to build the glass up with mat on the inside and outside. If you need to make a shape such as a channel....the use a wood form and put the wax paper over it and lay up the single layer of glass and you have a channel that can be cut to proper size and bonded on the old glass to use as a form to continue to lay up the mat cloth over. I hope this helps.

Dave 62 :seeya