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i've got a cracked 03 RM Switch Ltd. that's a year out of warranty. It blows, I know, so I've been sulking and feeling guilty about thrashing that baby for a few weeks, but now I just want to get back out on a ride! Anyone know anything about where I should go from here? Should I try to get in touch with a local framebuilder or could I just go with a general aluminum welder? I was referred by a local bike shop to talk to Frank the Welder at Sinister Bikes. Any idea on how long this welding would take or cost?

Thanks, and thrash it hard!
 

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pronounced may-duh
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I would go back to where you bought the bike or to the manufacture. Even out of the warantee period a good shop / bike company will make you a deal on a replacement frame. Remember it never hurts to ask.


As for repair, I'm no expert but I would be wary of a repaired aluminium frame.
 

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Aluminum can't be re-welded to its original strength like steel can. If you weld it, it will be barely any stronger than not, and you run the risk of a major breakage. I would just replace the frame rather than attempt to repair it.
 

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somewhat_absent said:
I was referred by a local bike shop to talk to Frank the Welder at Sinister Bikes. Any idea on how long this welding would take or cost?

I agree with the guy who said you should talk to the manufacturer, warranty or not. Frank the Welder is legendary and should be able to fix your frame - although if it's 6061 the heat-treating might be a problem. I agree with the guy who said you should talk to the manufacturer, warranty or not. I'd get an estimate for both a replacement and a repair. The manufacturer may let you have a frame at cost,
 

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Lopen is sneller....
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As above try and get a deal through your LBS or RMB. I have good experience with RMB...

I had an aluminum chain stay re-welded and it's still holding up (about two years now). I would however not use that particular bike for anything else but XC and even then I'm worried it will leave me on the mountain some day.

Good luck!
 

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Sorry, I'm a materials engineer and I can't help but to correct a couple things. Steel cannot be welded to it's original strength, there is always a heat effected zone. Post weld heat treatment is usually not required with steel, but the HAZ will have different structural properties than the parent metal.

Heat treating AL isn't as hard as some make it out to be, especially with a swing arm that can fit into a home oven. 6061 heat treatment can be done in the 320 to 350 degree F range, 7000 series AL can be done much lower (room temp if you give it enough time but it is accelerated with temp). You would want to bring the 6061 down to T4 or even T0 after welding to balance the microstructure of the entire swing arm as much as possible, then bring it up to T6. Everything can be done with your oven and a bathtub. If you are married just make sure your wife isn't around with you use the kitchen and bathroom to fix your bike.
 

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Just a flesh wound
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Sorry, I'm a materials engineer and I can't help but to correct a couple things. Steel cannot be welded to it's original strength, there is always a heat effected zone. Post weld heat treatment is usually not required with steel, but the HAZ will have different structural properties than the parent metal.

Heat treating AL isn't as hard as some make it out to be, especially with a swing arm that can fit into a home oven. 6061 heat treatment can be done in the 320 to 350 degree F range, 7000 series AL can be done much lower (room temp if you give it enough time but it is accelerated with temp). You would want to bring the 6061 down to T4 or even T0 after welding to balance the microstructure of the entire swing arm as much as possible, then bring it up to T6. Everything can be done with your oven and a bathtub. If you are married just make sure your wife isn't around with you use the kitchen and bathroom to fix your bike.
I had a Jekyll frame welded a few days ago. Cracked at the top tube to seat post weld. It is 6061 T6. I was going to bake it at 175 Celsius for 4 hours. Do I need to do anything else? Someone said I needed to heat the HAZ and quench it. Then artificial aging.
 

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Hopefull Fix

]Just got my frame back from the welder. Going to try to get alittle more out of it. I had him install another support tube to add extra strength to the weakened old crack site. Check the pic. Hope it holds. (for my sake)
 

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Complete Newbie in need of advice

Hi everyone

Have been following the forums for a while V interesting. I have a question? My son has just bought a used kona king kikapu frame cos he wants to build a bike from scratch. The frame has been welded right up front where the frame meets forks/handlebar joint. Weld looks clean but he has been told not to risk using it by a guy in a bike store because it is an AL frame and so can't be welded safely. Is this true? and if not how do we check if the weld has been done well? Seller just says he thinks it is fine but will refund purchase price if we are not happy. Son would rather keep frame if possible but will take advice as he obviously doesn't want to build an unsafe bike or sell on an unsafe frame

Any advice gratefully received
 

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Hi everyone

Have been following the forums for a while V interesting. I have a question? My son has just bought a used kona king kikapu frame cos he wants to build a bike from scratch. The frame has been welded right up front where the frame meets forks/handlebar joint. Weld looks clean but he has been told not to risk using it by a guy in a bike store because it is an AL frame and so can't be welded safely. Is this true? and if not how do we check if the weld has been done well? Seller just says he thinks it is fine but will refund purchase price if we are not happy. Son would rather keep frame if possible but will take advice as he obviously doesn't want to build an unsafe bike or sell on an unsafe frame

Any advice gratefully received


Since the weld is of unknown "pedigree" I wouldn't take the risk. My two cents.
 

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Has reapir held up ?

]Just got my frame back from the welder. Going to try to get alittle more out of it. I had him install another support tube to add extra strength to the weakened old crack site. Check the pic. Hope it holds. (for my sake)
Hey has the weld repair on your bike held up? Please let me know I have a nice frame i want to get repaired thanks.:confused:
 

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lasted for about 10 rides

Hey has the weld repair on your bike held up? Please let me know I have a nice frame i want to get repaired thanks.:confused:
It lasted for about 10 rides. I had a major failure when I was clearing a fallen tree. I was lucky i did not get hurt. It was ugly . It broke in 3 places like a ripped open pop can.Long walk back. If you can afford it. I would buy a new frame.
My KHS frame was about 8 years old when I repaired it. That probably had something to do with the major failure.
Good luck.

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