Cutting up bikes (caution)

[Uncle Stretch]

Ok I chop up alot of bikes and build other bikes out of them. I watch everybody here doing the same thing. I can weld pretty good ,but I'm going to tell you right now there are very few welders that can cut those thin chain stays apart and but weld them without having a problem. I have tried to show in my posts that I dont take the chance of something breaking. I stick something inside those tubes and weld it all together. The weld has something to weld to other that two thin pieces of tubing, and you get the added benefit of having something to add a little strength to that joint. Check what your doing. Grab a couple pieces of that 3/8 tubing ...stick it together and weld it....then stick it in a vice and whack it with a hammer and see if your weld holds. If it dosent....START PUTTING SOMETHING INSIDE. You can get hurt really bad if your riding along and one or both of your chainstays break ,or any of the but welds on your frame. Chop um up but for God's sake be careful. :shock: :wink:

 

[Danimal]

Aaaaah yes, butt-joint welding is never easy. However, I remember from my school days that a properly welded joint should ALWAYS be stronger than the metal it joins. So if you're a good welder (which I no longer am) that should not be an issue.

I remember getting handed 6 pieces of sheet metal and a fitting. We had to weld them together (actualy, I think it was just with a torch-no brazing rod or anyting) into a cube and weld on the fitting. Then it was put into a blast cabinet and connected to a high pressure air line until the box exploded. You passed if the metal broke, fialed if the weld broke.

Don't try that one at home kids.

 

[sensor]

yup....always sleeve(i have to do it when i replace any 1/4panels on cars at work.icar makes us)
when i sectioned my kids bike i sleeved everything and i beat the heck out of that thing before i gave it to him ....that thing will never break.
i tried :wink:

 

[Uncle Stretch]

In a good situation a weld is stronger than the metal around it. Take two rusty 3/8'' tubes and booger weld them together and your asking for trouble. I'm really trying to let people know ,it fine to learn how to do something and with welding practice makes perfect , but at least stick something...3/8 solid rod or something inside and help hold three tacks and a couple burn throughs. :shock:

 

[Danimal]

In a good situation a weld is stronger than the metal around it. Take two rusty 3/8'' tubes and booger weld them together and your asking for trouble. I'm really trying to let people know ,it fine to learn how to do something and with welding practice makes perfect , but at least stick something...3/8 solid rod or something inside and help hold three tacks and a couple burn throughs. :shock:

You are absolutely correct. I guess my story is the exception when working on rusty old metal. :mrgreen:

Dan

 

[karfer67]

if i were going to do something like that i would always have some sort of iner tube helping to hold the two together. i see all sorts of creepy things come in the shop that in all honesty have no bizz being ridden at all. and i have to politely tell them that me working on their bike is a liability and i cant do it lol. this goes the same for hot rods some of the stuff i see at mass and billetproof make me cringe mechanically speaking.