I was thinking of rewelding my CMF frame to make it "better than ever" but after I did a search and read this
http://pentonusa.org/forum/topic.asp?TOPIC_ID=1712&SearchTerms=cmf,welding
I figured it was a not such a good idea. Of course that was from 2002. Is there anything out of late that says differently?
Pete Petrick
Penton 175 Jackpiner
Pete,
I don't know exactly what you're referring to with regard to "welding" your frame, but if you're just welding up cracks, "in the day", we just used a TIG welder and a mild steel rod as opposed to an alloy rod. And I don't remember re-breaking any welds.
Dane
I use a MIG welder and have had no problems at all. .025 wire Argon/CO2 mix, low heat works great #3-#4 on wire speed. On a lot of the frames, you can still find bits of wire still from the original factory welds. Happy Holidays!
Pete,
I can give you up to date photos of a race where doing double jumps on a CMF 125 flattened (squared)both rims and bent the 32mm fork tubes out a couple inches.
One week prior to the race I had two TIG welds done to stop cracks from elongating. One crack was at the lower front motor mount. The other was located near the steering stem / frame mount area. It has been over a year now with 5-6 more tough outings on the bike and no failure to the frame.
If you need this done for safety get-r-dun. If it is for cosmetics...thats your call.
Well when I posted my question in 2002 I never got an answeron " if I had the only two sloppy welded frames " and now thks Kip you have answered it for me. By seeing some frames with wire still in the weld pretty well answers it .... thks again Brian
Brian Taylor
Brian Your welcome. I normally weld the frames really good and then go over or grind off the perfect welds. I then reweld and leave a "pop" or wire to give the bike the original look. John Cooper, the best welder I know, taught me that one!;)
I believe when the CMF frames were welded originally they were stress relieved. I think this keeps the tubing from cracking right next to the welds.
Rocket
Thanks guys. Now all I have to do is find a practice frame to develop my CMF/wirefeed skills on! I have the feeling that a little experiance might help here.;)
Pete Petrick
Rocket:
When the frames were manufactured at KTM, they went from the welding department to the shot peening chamber and then right onto the paint line. I don't know if the shot peening chamber was actually designed to stress relieve the frames, but I suppose that it may have helped some. The main purpose of the shot peening was to clean the frames for painting.
Dane
Dane
That is good to know, I have repaired some frames with a MIG welder and always wondered if it needed to be stress relieved.
thanks
Rod
whoo boy, and all along I've been stick welding them back together !!
Raymond
Down East Pentons