Need quick help with epoxy/welding problem:
 

I'm at yet another impasse with the 356, the engine is now ready to go in save for this little problem with the heater boxes. I've let this one go until now because I was busy with other things but now I need to solve it or install them with no working heat and deal w/ it later. (They were not previously working).

Basically, I need to attach this shaft to its flap/valve while it's installed in the HB. I took it to my welder and he could not assure me that his MIG welder would not warp/melt the flap even with a small/quick tack weld. The factory somehow crimped these on with a tiny weld, you can see the marks on the shaft and flap.

I either need to drill tiny holes in both parts and find small screws and/or use some super-duper epoxy that is heat-resistent to attach the parts together. I don't know my epoxy products and this would be a 1-shot deal, ie. if it does not work, the part would be really mucked-up.

New heater boxes are available for ~$300 each but need to be shipped. I need to install the motor today and would love to fix this box cheaply. Thanks in advance as always. :cool:

Here is the offending part:
http://forums.pelicanparts.com/uploa...1297450034.jpg

Know anyone with a spot welder?

If you won't be able to get at it again easily, I'd drill, tap and machine screw with lock washer and high tensile strength (2 hour) epoxy.

JB Weld will work, as with all epoxy, surface prep is everything.

If it has to go today, JB Weld is fine...how hard is it to get to later?

Is JB weld really heat-resistent? (Never used it).

Any work involving heat exchangers is an engine drop + exhaust removal. Which is not the end of the world on these cars but it would be nice to fix this one before installing. The HE on the other side is junk so the engine is coming out again either way but I could at least have heat on one side.

That would be a great repair but for time reasons it's dead. Thanks just the same. :)

what about drilling through it and rivet together, or grind a flat spot on shaft and use a punch to get flap in close approximation to flat spot

How different is that piece from a bug of similar vintage?

What about drilling a hole through the shaft/flap and using a cotter pin?

If you need to weld the flap to the shaft, I would simply drill a couple small holes in the flap where the original crimp indentations are and then I would simply rosette weld them with the tig welder..... Very simple IMO...

http://forums.pelicanparts.com/uploa...1297451460.jpg

Drill and cotter pin then, don't trust the epoxy in torsion.

Sure sounds possible. Maybe I'm missing something. Most if not all the above suggestions are excellent. What's so hard about drilling through both pieces and driving an interference-fit pin in there? Or as Tim says, open a couple of little ports in the sheet metal, and weld there. If the engine and exhaust will need to come out eventually, then you lose nothing with the gamble. Worst case scenario: The sheet metal gets a bit warped.

I'd drill a small hole through the flap and the shaft and pin the two together. Possibly two small holes, one on each of the flats. Alternatively, do as Graham suggested and find someone with a spot welder.

THIS IS THE WAY TO DO IT. There won't be any warping problems.

Short of this, epoxy the shaft to the flap. The problem with that is getting enough epoxy between the sheet metal and the shaft.

Rosette weld..... I promise it will work perfectly and is the easiest/quickest way to get the job done right. (unless of course you have a specially configured tongs for your spot welder that can fit inside the heat exchanger opening and still squeeze/weld the parts together)

Spot welding is what I would use. Gotta be someone around with one. I have a small one from HF that I use...

Maybe there is an issue of semantics here. I don't see how anyone would get a spot welder down in there.
It was swedged on to begin with. That might be an option, just deform the hole in the plate so badly that you have to hammer the shaft through it. Inelegant, yes, but it would work just fine. I would probably do just that if it was mine, but Tim's suggestion is the best permanent, fool proof solution.

I've used it to fix rusted out holes in mufflers. Surface prep is everything.

Honestly, Tim, WTF do you know...I mean, really;)

Yep or a timed spot blast with the TIG torch. I weld Nickels together with out filler rod.

With Epoxy your always going to be thinking of it.

Yeah.....like he's ever welded anything:rolleyes:

If welding isn't an option, how about drilling a small hole & driving in a split, tapered pin?

As explained above, two small holes with some rosette welds won't get it very hot and will hold just fine.

If I had my TIG here Denis I could do it easily for you.

I'm thinking about purchasing one again soon.

Thanks for all the replies. Tim's solution is the winner, I just need to go to the welding shop and have them TIG weld it. I already drilled the holes. I'll post some pics later. Thanks again! :cool:

Done deal!
 

As usual, this board rocks. Tim's solution was the best because what I did not show previously is that the flap has a small bracket on the back that attaches linkage to the other flaps and is under minor stress. Minor but enough to make the "smush it together" or epoxy fix a probable (quick) failure. I knew that it needed to be welded, just wasn't sure the smartest way. It also needed to be repaired with the whole thing assembled.

Here are the holes:
http://forums.pelicanparts.com/uploa...1297462438.jpg

Here are the linkage rods:

http://forums.pelicanparts.com/uploa...1297462493.jpg

Took it to my guys @ Hollywood Welding. This is where James Dean would have taken any welding work on his bikes or cars, not to mention McQueen, hell, Errol Flynn for that matter. Look at the year on sign: :D

http://forums.pelicanparts.com/uploa...1297462634.jpg

And done! A good day so far. I managed to also fix the other one which was really mangled. Pretty sure that they will both work. New repros are available but pricy, ~$600 for a set. :cool:

http://forums.pelicanparts.com/uploa...1297462767.jpg

Believe that this might have to be nominated for "post of the month" if not year...

Good to hear you got it fixed..... I hope they did not charge you much as that is a piece of cake with a tig welder. A wire welder could have worked also, but when tig welding through a rosette hole one can be 100% sure that the shaft gets melted/penetrated prior to dipping in the filler rod thus melting/mixing it together with the outer sleeve. I use rosette welds all the time when internally splicing chrome moly aircraft tubing.

While some of the other ideas would have worked, five years from now Seahawk won't have to explain to his wife why his heat system just started acting up in his silly old German toy car as they are on a fall color tour two hours from home. ;):D

Keep up the good work Denis... don't let Seahawk rush you... quality resto work like you are doing takes time. :D

Seriously. Shakespearean.

Yeah, me too.:rolleyes:

Fixed it for you.

You guys should have seen the crap I cobbed when I was a broke high school and college student.... I had zero patience, knew just enough to get in trouble mechanically and I was satisfied with a repair that lasted a week. ;):D

Competitive MX motorcycle racing, building model then real airplanes, a mechanical engineering degree, buying old beat up Porsches and acquiring a few gray hairs somehow changed my attitude over the years..... I pretty much am to the point that when it comes to mancave projects I live by the old saying: If it "ain't" right it's wrong..... :D (Of course this is just my opinion... my wife would disagree when it comes to me working on/improving "her" house ;):))

I have no idea how much past experience Denis has on projects like this, but he appears to be detail oriented and seems like he has a similar mindset on approaching this type of preservation/resto work. I especially liked how he figured out a clever way to wire brush the torque tube interior prior to painting them. It probably did not "need" to be done, but damnit... it just would not be "right" to pimp slap the clean shiny parts back in there with that tube looking like hell inside.

Keep up the good work Denis! I know all too well how tempting it is to rush the last few tasks when nearing completion of a long term project.

Thanks, Tim. For the encouragement as well as the solution to the flap issue. I have zero experience with 356s before this but a bit of 911 DIY time including rebuilding the engine of my SC back in '02(?)

I'm not capable of rushing on something like this, just too OCD or something. I'm putting on the engine sheet metal right now and it's going slower than I anticipated because some of the pieces are bent a little or whatnot and need massaging to fit right. Every part and fastener is getting cleaned and oiled, (if applicable), I just do it the exact same way as if it was my own and I know how I want it done.

And I agree that something is either "right" or it's not. You and I could rebuild a car or bike together and get along fine. I'm completely deranged with automotive/mechanical OCD.

I'm just happy to see that he fixed the old parts. We have all gotten it into our heads that we live in a disposable society, and it's better to chuck something, and buy new ones. Those old, tough S.O.B.'s that we admire here from time to time wouldn't buy a new part unless they screwed with it for a week, and mangled it beyond recognition. Nice to see that spirit is still alive and well in some of us.

:D I have been known to blow a whole weekend making/fixing a $50 part... I am addicted to the feeling of satisfaction from making something old and broken work like new again. ;):)

I do the same thing. I'm just too damned hard headed or stubborn, or both to admit defeat. I call it "tinkering" or my hobby. But I've also learned a lot over the years. I walk the aisles at the hardware store every once in a while taking mental notes on things I can use as tools, or substitute parts later down the road. But none of these things were designed to do what I intend to use them for! I think it's a sickness.