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Bending Schwinn Steel

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Rob_STT🌴USVI

'Lil Knee Scuffer
Hi again everybody. I posted something on the Birds of a Feather introduction. I believe I used the wrong approach of bringing this topic up.

To that end I’ll open up a new topic. Specifically it has to do with the temperature for making Schwinn steel malleable, under these circumstances.

I was also concerned about whether I should gypsy steel in water or not and whether I can do structural damage to the bike by just trying to heat it up with a propane torch. Here is the post that I did in birds of a feather.

I am wishing for comments about the process before I go ahead and do it ………⤵️

My Post : Hi everybody.
🚲🦯 I recently bought my dream Schwinn, a 1956 Corvette from eBay.

Unfortunately, the genius who packed it, for some reason, took out the lower bearing case and some other genius (may be me) dropped the frame to put a kink in the front of the fork. It has a slight egg-shape to it

Having been a inhabitant of boat yards for many years, I thought the best way to make a perfect circle in the frame would be to use boat saving hardwood bungs.

Having been the son of an auto body shop person, I figured that the way best to bend steel in bumper bracket is by heating it red hot with a torch and hit with a ball peen hammer, wearing safety goggles and gloves.

I bought those things to do the job. My theory is the heat the steel in the fork just enough to drive the bung down to make a perfect circle.

Any comments?

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I'm not sure you have to get that red hot to re-shape. The steel alloy they used is pretty soft. I think the wooden bung as a shaping peg is a good place to start if that peg is perfectly round and the wood is a hard variety, but I would use very gentle heat to start rather than going red hot. Going red hot will ruin a lot of head tube paint. You would also have to knock out the other headset cup if you go that hot, so as not to anneal it. I would remove the headbadge before you start working. There are two small, delicate screws that you don't want to damage with the bung. If the bung doesn't work because the wood is too soft, a similar tool in brass might go better. Make sure you do not go too far and funnel it out - the cup to headtube fit is fairly precise.
 
I wouldn’t touch that with a torch! Also, the head tube was made from two pieces of flat steel and there’s weld lines inside. I’d bend that back out with a crescent wrench. Get a piece of PVC pipe that fits the outside of the head tube cut it in half, place it on the face so you don’t Booger up the outside and start bending it back with a crescent wrench. Keep checking the fit with the bearing cup as you bend it out. As long as the bearing cup fits and it’s not sloppy or too tight it should be good.
 
To get the head tube to accept the race I would find a block or metal buck approximate to diameter of original tube. Using a c- clamp on inside - or oblong area and bring pressure till I see it returning to shape. And I think damage is only limited to °100 of a 360 circle. I have used the locking fork race to bring that area back to something that can be used again .
 
your dad the bodyman would laugh and shake his head at the thought of heating it up to fix that.

your wood wedge would be the ticket if it were metal, though it may work. try that first and see what happens. don't use heat. you can't make it worse with wood

otherwise get yourself a piece of round steel like in my blurry pictures. stick it in being sure the other end is not all the way in so as to bend the other side.
work it around and push it back onto shape until the race fits, after the tube pushes it out you may need to tap it back down.

what? you don't have a shelf full of random steel scraps in your garage? in that case that ball peen hammer should do the trick. use light taps until you get a feel for how much effort it takes the metal to move. fit the race in as you go. slow and easy is the key here. if you over stretch it, you have to hit it back where paint is, so try to avoid that. use the round end on the hammer. 🙃

I could have fixed it and had a beer in the time it took to write this. I have been hitting metal with hammers for a long time.

looking around here I have a big Cresent wrench that could be used instead of the steel bar. maybe a jack handle or breaker bar for a socket set.

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Wow
I’m sure glad I posted this.

The only power tools my dad ever touched were things to work on the wooden boats that he obsessed over. He had workman to do the other stuff. They seem to love the torches. They always liked me, the boss’s son. Roberto would probably do it for me.

Fast forwarding to the year 2022, I gave myself till sundown (Shabbat) to make a decision on doing this and I’m glad I did.

The fancy work plan is scrubbed. I will work with conservative measures. That plug is a very hard wood, probably oak.

Thanks everyone… will keep you advised.

no heat no heat no heat :)
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Hi and welcome to the CABE.

As soon as I saw your post I thought of the two fork repairs I've had done this towns local bike building legend Bernie Mikkelsen. He's been building frames for professionals since the 70s and knows his steel. Straightened out the S shaped forks on my teens Pierce some years back and then a fork on an Albert Eisentruat bike that seemed to have been hit from the side. His tools of choice are pieces of 2x4s, vice, rope and a long steel lever that started life as an axle on a 1920s Ford.🤣 I need to add that Bernie was paralyzed on the right side from a stroke some years ago.

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As said above, his advice was that bike steel is very malleable as long as it hasn't been kinked or work hardened by repeated bending. After reading the other great suggestions I was wondering if a piece of shovel handle or something similar of the right diameter could be tapped in from the undamaged end. This would avoid damage to the exterior paint and the force would be reverse from the original blow. Bernie and other's like the late great CABER Mike Leebolt told me numerous times metal has a memory and may go right back with some gentle persuasion.

I have truss rods that had been damaged similar to your head tube. Mike told me to drill a couple blocks of wood the diameter of the rods, cut them in half so they make a form around the steel and then using a dead blow mallet gently pound them back to shape. He also suggested squeezing them back into shape using a C clamp or vice and the blocks, much like using a swage to shape hot metal. Both methods worked well for making slightly mashed oval tubing round again.

Good luck and I appreciate your families wooden boat legacy. I've crewed on a number of large 19th century wooden schooners in the distant past. Wooden boat folks are the best!
 
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Hi and welcome to the CABE.

As soon as I saw your post I thought of the two fork repairs I've had done this towns local bike building legend Bernie Mikkelsen. He's been building frames for professionals since the 70s and knows his steel. Straightened out the S shaped forks on my teens Pierce some years back and then a fork on an Albert Eisentruat bike that seemed to have been hit from the side. His tools of choice are pieces of 2x4s, vice, rope and a long steel lever that started life as an axle on a 1920s Ford.🤣

As said above, his advice was that bike steel is very malleable as long as it hasn't been kinked or work hardened by repeated bending. After reading the other great suggestions I was wondering if a piece of shovel handle or something similar of the right diameter could be tapped in from the undamaged end. This would avoid damage to the exterior paint and the force would be reverse from the original blow. Bernie and other's like the late great CABER Mike Leebolt told me numerous times metal has a memory and may go right back with some gentle persuasion.

I have truss rods that had been damaged similar to your head tube. Mike told me to drill a couple blocks of wood the diameter of the rods, cut them in half so they make a form around the steel and then using a dead blow mallet gently pound them back to shape. He also suggested squeezing them back into shape using a C clamp or vice and the blocks, much like using a swage to shape hot metal. Both methods worked well for making slightly mashed oval tubing round again.

Good luck and I appreciate your families wooden boat legacy. I've crewed on a number of large 19th century wooden schooners in the distant past. Wooden boat folks are the best!

I thought about the method you mentioned using a shovel handle or something driven in from the bottom end. Only problem with that is the EF'd Schwinn's head tubes. They are not smooth inside like a piece of pipe. These head tubes were stamped from two flat pieces of steel and then rolled and electro welded together. They were then sized, and the two ends were cleaned up for the bearing cups. There is usually weld slag at the front and back between the ends of the cup area.
 
That steel is 1010. It is on par with rebar or melted car bodies. Not an alloy, just a cheap, easily welded steel. It is easily worked for a minor bend like that.
You shouldn’t have to heat it to bend it to where you need it to be. If you have a custom exhaust shop with a hydraulic tubing bender, close by, you can probably slip him a few bucks, and he will use the expander collet and make the frame perfect. But, working it with hand tools will work, also.
Good luck.

Ted
 
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