Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 11-06-02, 09:51 PM   #1
B1105
Senior Member
Thread Starter
 
B1105's Avatar
 
Join Date: Oct 2002
Bikes:
Posts: 592
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Cracked aluminum frame, able to fix by welding?

Hi, I have an aluminum Klein Quantum frame and recently, the derraileur hanger cracked. It did not break off, but is cracked on one side. I was wondering if there were any forms of welding the hanger back together would be possible, (its not a replaceable hanger), so, if anyone has some feedback, that would be helpful.
Thanks
-Byron Ling
B1105 is offline   Reply With Quote
Old 11-07-02, 06:46 AM   #2
D*Alex
Banned
 
Join Date: Aug 2001
Location: upstate New York
Bikes:
Posts: 1,688
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Yes, there are, but they will be difficult to do in a small repair. Have you talked to a decent frame builder, or perhaps a welder? Have you called Klein?
__________________
Je vais à vélo, donc je suis!
D*Alex is offline   Reply With Quote
Old 11-07-02, 02:28 PM   #3
Big Johnson
Senior Member
 
Join Date: Oct 2002
Location: Colorado Springs, CO.
Bikes:
Posts: 83
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
A good welding shop should have a TIG machine, which is probably the method most appropriate for an aluminum bike frame. Also, check with your LBS to see if they can recommend anyone in your area who can perform such a repair.
Big Johnson is offline   Reply With Quote
Old 11-07-02, 02:32 PM   #4
sshock4
Apot.
 
sshock4's Avatar
 
Join Date: May 2002
Location: new brunswick, nj
Bikes:
Posts: 191
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
hah....good one byron

-Andrew
sshock4 is offline   Reply With Quote
Old 11-07-02, 09:23 PM   #5
bentbaggerlen
Senior Member
 
bentbaggerlen's Avatar
 
Join Date: Sep 2002
Location: New England
Bikes:
Posts: 714
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Yes, your hanger can be repaired. I done a few broken hangers on aluminum frames. I think Kline bikes are built with 7000 series alum. 7000 series can be allowed to air cool without any big loss of strength. You will have to remove the paint from the area, any paint sucked into the weld puddle will weaken the weld. I still don't know why any frame builder would build an aluminum frame without a replaceable hanger. Its not a huge job, should only take an hour or so. (hard to say without seeing it) Most weld shops would charge $50 or so, some more some less. You will need to strip down the frame. And after repairing the hanger you may need to realign the hanger.

There may be another way... Take a look at www.exposales.net they sell an aluminum brazing rod. It melts at 735* and flows into the gain of the base metal (alum melts around 1100*) A propane torch would work well. The rod is called HTS-735. I have not used it myself, but I have seen a few things repaired with it. I would not use this to repair a high stress aera such as a cracked headtube, but it should work on a hanger. the rod has a tensile rating of 45,000 psi and shear of 31,000 psi.

Good luck!
__________________
Bentbaggerlen
"When the spirits are low, when the day appears dark, when work becomes monotonous, when hope hardly seems worth having, just mount a bicycle and go out for a spin down the road, without thought on anything but the ride you are taking." - Arthur Conan Doyle
bentbaggerlen is offline   Reply With Quote
Old 11-07-02, 09:46 PM   #6
B1105
Senior Member
Thread Starter
 
B1105's Avatar
 
Join Date: Oct 2002
Bikes:
Posts: 592
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Dear bentbagger,
thanks for the reply, would any welding shop beable to do this? WHat did you mean by strip down? take off all the parts? thanks for this info
B1105 is offline   Reply With Quote
Old 11-07-02, 09:57 PM   #7
Dirtgrinder
Dances with Rocks
 
Dirtgrinder's Avatar
 
Join Date: Apr 2001
Location: Jefferson City, MO
Bikes:
Posts: 1,441
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You'll have to take off any parts near the hanger. The brake should be far enough away that the heat won't hurt it. If you have a chainstay protector I'd take it off too.
I would just call around to some of the welding shops and see if they can weld aluminum.
__________________
If everything seems under control, you're just not going fast enough...

To become a registered member of BikeForums Click Here
Dirtgrinder is offline   Reply With Quote
Old 11-07-02, 10:36 PM   #8
sshock4
Apot.
 
sshock4's Avatar
 
Join Date: May 2002
Location: new brunswick, nj
Bikes:
Posts: 191
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
and take off all the paint in the region. so it doesnt burn, or fall into the weld.

...
sshock4 is offline   Reply With Quote
Old 11-07-02, 10:40 PM   #9
B1105
Senior Member
Thread Starter
 
B1105's Avatar
 
Join Date: Oct 2002
Bikes:
Posts: 592
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
yea thanks a bunch
B1105 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 01:22 AM.