Thread: DIY rusted strut tower fix for dummies(Ive never done this before)

Howdy Bill. I think I skipped this one. I believe this is what ITHURTZ was talking about when a cobalt bit was mentioned. This is not a cobalt but a high speed which is what I generally prefer, of those two. But its the flat-nosed variety, with a little pilot point that likes to snap off. Cobalt ones are black and harder but won't take the heat too well. Either would work for this. So there are several ways to remove welds, but the Blairs are my favorite. They work as fast as if the part was bolted on.




Matt, I also forgot to mention that in this case its probably fine to drill your pilot hole all the way through. Makes centering so much easier.

...AND ... that if all else fails, you can use a regular drill bit or better yet a stepped bit. You would drill away both layers of the whole weld spots then make new plug weld holes right next to the old ones. Just a thought, I'm sure you're ready to get past this so the car can be mobile again.

http://www.menards.com/main/tools-ha...56-c-10079.htm

Thats the one menards has that I bought, I kept the speed lowish and used a few squirts of oil and had no problems. I use these for work, eats a schlage (is that even the correct spelling) deadbolt like butter. The cheaper door knobs almost like play dough.

Ah. OK yeah thats not a spot weld removal bit but is what I referred at as a "regular bit". Meaning the shape of the point. In cobalt (looks nitrided too). Still works! I have a $9 set of nitrided step bits from HF that I've used for many years, those would work fine too. Heck I've used a plasma cutter to do it before, lol. Working in this spot, neatness isn't as important. Just need holes! Maybe our hero will get it whooped over the weekend...

Weld locations should be very similar if not exactly the same, if you guys have the same kind of car.

It will be stuck good until all welds are out.

Be aware though, that some welds may be slightly larger than the cutter or bit. So they would still be holding. Same thing if you didn't exactly center the weld, the edge of it could still be holding. Thats when a step bit would be handy. If y9u have them all drilled out and can tell that one or more are still stuck when you try to pry it off, try to see which ones are still stuck and dish out that hole with the grinder. Just a little, then pull on the brace more and see where the weld is stuck.

Robots weld it at the factory and as long as it passed inspection, a sloppy weld or two wasn't a big deal to GM. So you do find oddly shaped spotwelds, and they don't always quite fit into a 3/8 circle. Especially if the pilot wasn't centered. Thats one of the hard parts. Find you a good 90 degree angle pry bar of some sort and get under that brace so you can pry against the tower, because its not unusual to have to swear a bit getting a part like that off. Pry, grind, drill, cuss, repeat. Don't have your face under it when it pops off!

That flat-nosed bit I showed... they have 6, 8, and 10mm versions. On structural pieces like this, welds tend to be larger than the 6-8 mm and many times I'd reach for the 10mm.

Remember, its like breaking a single strand of wire by bending it, kinda. If you get the brace loose enough to move, rock it back and forth to loosen until you can eventually rip it off there. Don't worry much about bending the brace, you can hammer that flat on the ground after its off. They sure put a lot of randomly placed welds in it, didn't they? Thats overkill on purpose because sometimes the robot misses.

After the brace is off- theres an option to consider, let me explain:

You could weld up all the holes in the brace while its out, then grind them flat on top of it. Then you would have little or no drilling left to do because you would use the old weld holes in the tower. Plug weld it from inside the trunk and gravity would be on your side with the weld kernel. Since the heavy gauge piece is on the bottom, theres every reason to do it that way, but you would be in a very tight spot and up there by stuff that could burn or catch a spark. But man, it would weld up better that way.

The alternative is to drill new plug weld holes near the existing welds in the brace and leave all the holes you just drilled in everything. That means you end up with swiss cheese holes all around your strut mount that go all the way through to the trunk. Gotta seal those up, and hmm, did it get weaker? Maybe. Plus, you would be welding the thick lower brace to the thin upper tower metal while defying gravity with the weld kernel. Less than ideal.

I would probably end up doing as many from the top as I could. A guy could take out the speaker shelf and maybe gain some access from inside. Be sure to protect the back glass if you weld any up top. Wetted cardboard ain't bad for that.

Sorry such a long post, but I'm glad to share my experience. These bodies just don't rust much here, so I've never done one. Fixed plenty of bent W-bodies though.

Matt I had that same problem, drilled all my spot welds, and found out I had 3 not perfectly round spot welds that were still attached to the car. I just used a screwdriver to try and "pry" the plate away from the car and see where the metal seperated and where it was still stuck. I wont lie though, I got fed up with one of them and went nuts with the air chisel, 50/50 regret that haha. Good to see your getting under the plate (only took my 30min to get it off btw )

This is great, I turn to the claw hammer at the house for everything. Again, I'm glad to see this repair demonstrated. It looks to me like you're doing fine. Them pics are kinda small though, lol. I learned my lesson about showing fresh welds on the interweb. People don't get it.

Spray bottle some water onto cardboard to block off the sparks. By all means yes, get that rust off the tower and coat all the bare metal that will be hidden behind the brace. If you really want to knock the rust off without hurting the metal too bad, you need some sandpaper or something like a scotch brite wheel from the drill bit store maybe? Don't want to thin that tower metal any more than necessary.

Cutting the hole-

Cut a triangle instead? You da boss. Or you could drill a series of holes with your small bit real close together. Perforate a circle, then knock that out.

Originally Posted by ITHURTZ

I got fed up with one of them and went nuts with the air chisel, 50/50 regret that haha.

Sometimes it be's that way. Man, I'm glad you turned him onto that bit. We had to drill some stainless oh, 16 gauge awhile back and everybody in the shop just about ate up all their bits trying to get holes in that stuff. If you guys want some super-handy bits though, try some stepped or "uni" bits. I use them often and its better than having a boxful of sizes if you're working sheetmetal.

Oh and Matt- sorry the cutter didn't work out for you. But I got about the same use from that product as you did. With lots of practice, I can now usually wear out a cutter before breaking a tooth off. Its something that a guy has to get a feel for. Better luck on the next $30, man.

Uni's are nice, Used mine once and lost the dam thing, there went a big chunk of change.

Matt, I set about 5 fires when doing my rockers and struts. One of the times I was 99% sure my car was going up in flames. I never ripped my interior apart so fast before in my life to put those flames out. That big one was in the rocker area though, but from the bottom of the car to the bottom of the coupe small window. After that I armed myself with a big spray bottle of water.

You also didnt need to drill 100% through the metal, only the main plate was needed! I just replaced the factory spot welds with my 3/8 hole and filled it with the mig.

Oh ya, when I delt with my rust I used a siphon blaster, then figured I would try out rust bullet, and their blackshell top coat.
Rust bullet applied to my rockers, 2 coats
8byu by smetters20, on Flickr

Then topcoated with 2 coats of blackshell, dries hard as a rock.... on anything it touches
6bf461c5eb0decb73ad177ab77d8cd7e by smetters20, on Flickr

I also old schooled my undercarriage
db7102d2addb3d9fa5203030a428f6e0 by smetters20, on Flickr

97ni by smetters20, on Flickr

Its fun to try new and old things out

So back to work today..Still not done wish I was but taking my time making sure I'm not messing anything up starting welding the new sheet metal in.

[IMG]Welds look pretty rough really hard to get in up top there have to weld with one. But I think there mostly penetrating and I plan On welding from the wheel side aswell.
[IMG]Coming along alright tacked it from wheel side to start off used the 1x1 to hold up the sheet metal well I put couple tacks in. Only problem I'm having now is a couple of my edges are slightly raised to the sheet metal behind it. I tried bashing in with hammer didn't seem to do much. Anybody else have any suggestions or had similar problems?
[IMG]Welding in my first spot weld hole conveniently in one of the spots I drilled to spot weld from the top of the sheet metal(not :| ) So ended up filling the hole. I'm gonna spot weld couple from the top then get 4 or so on the bottom and spot weld the edges. Really Really hoping I'm getting back on 4 wheels tommorw!

Subbed.

Looks to me like its coming right along. Having an assistant back up (maybe hold a piece of 2x4 or a metal dolly against the backside) of what you're hammer bashing. The hammer has more effect if the work piece can't bounce when you strike it.

Looks good, Now I would like to see a beautiful painted and finished photo next!

This thread makes me so happy that I don't own a GP.