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


Go Back   > >

Framebuilders Thinking about a custom frame? Lugged vs Fillet Brazed. Different Frame materials? Newvex or Pacenti Lugs? why get a custom Road, Mountain, or Track Frame? Got a question about framebuilding? Lets discuss framebuilding at it's finest.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 12-10-09, 09:20 PM   #1
clasher 
Senior Member
Thread Starter
 
clasher's Avatar
 
Join Date: May 2009
Location: Kitchener, ON
Bikes:
Posts: 1,913
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Aluminum chainstay burst

So, I got a free frame that someone claims water froze in the chainstay and it burst, leaving a small crack. I think is true because the crack has forced some material outwards, and when I took the BB out, water poured out of the frame and all the seat tube was all wet when I took the seatpost out. Anyway, I didn't do it but I since the frame was free I thought it would be worth experimenting with a repair.

So, anyway. I'd like to repair this frame and ride it as a commuter/round-town bike. By far it's the most new-fangaled bike that I've ever had, and the only aluminum one too. I didn't pay for it so I can't just "Get a new frame" as everyone commonly suggests with these sorts of threads. I'm not sure I'd buy a new aluminum bike in the first place... anywho.

Here's my plan for the repair.

Drill stop holes at the ends of the crack to help stop its spread. File away the material that "burst" above the surface when the chainstay opened up.

Clean off all the surrounding paint and clean the area thoroughly.

Now, I have either two options. TIG weld the crack and then fabricate a sleeve and then weld the sleeve to the chainstay to reinforce the whole area. Judicious use of heat sink clay would hopefully minimize the damage from heating the frame up with welding.

The other option is to do the same repair, but using HTS-2000 brazing rods. I like this idea, but they almost seem too good to be true... but I'd basically follow the same procedure as with TIG welding it.

Here are some pictures:

clasher is offline   Reply With Quote
Old 12-11-09, 07:19 AM   #2
mudboy
Senior Member
 
mudboy's Avatar
 
Join Date: Sep 2008
Location: Collegeville, PA
Bikes: Ruckelshaus Randonneur, Specialized Allez (early 90's, steel), Ruckelshaus Path Bomber currently being built
Posts: 1,354
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It's a low-stress area, and if it did fail, it wouldn't be catastrophic (i.e. having you go ass over elbows). I'd just throw some duct tape on it and ride it.
mudboy is offline   Reply With Quote
Old 12-11-09, 08:01 AM   #3
KNEEL
Member
 
Join Date: Apr 2009
Bikes:
Posts: 49
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by mudboy View Post
It's a low-stress area, and if it did fail, it wouldn't be catastrophic (i.e. having you go ass over elbows). I'd just throw some duct tape on it and ride it.
I'm inclined to agree, but if I was to weld it , I would probally hog the crack out with a small burr to make a groove and then weld it. I can smell the burnt powdercoat from here........blecch! good luck!
KNEEL is offline   Reply With Quote
Old 12-13-09, 03:10 PM   #4
clasher 
Senior Member
Thread Starter
 
clasher's Avatar
 
Join Date: May 2009
Location: Kitchener, ON
Bikes:
Posts: 1,913
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Clean it out and duct tape it. Got it! Maybe I'll use gorilla tape...
clasher is offline   Reply With Quote
Old 12-15-09, 07:46 AM   #5
Mark Kelly 
Senior Member
 
Mark Kelly's Avatar
 
Join Date: Oct 2009
Location: Willy, VIC
Bikes:
Posts: 637
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
It's aluminium, so you can glue to it quite well if you prep it properly.

I'd grind the damaged portion flat, take the powder coat off all around the tube, etch the aluminium and wrap it in carbon fibre and epoxy - three or four wraps of the tube should do. Probably end up stronger than the original and not too obvious, given the black powder coat.

This is easy for me to say because I have several types of CF cloth and the appropriate resins in a box in my shed but they are easy to buy from your local fibreglass supplier and they are not that expensive.
Mark Kelly is offline   Reply With Quote
Old 12-21-09, 03:39 PM   #6
Mudu93
www.markreynoldsfund.org
 
Join Date: May 2005
Location: Illinois
Bikes: 1993 Titanium Miyata Elevation 8000, Scattante XRL
Posts: 461
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
That had to be what happend on the steel parkpre frame I posted about. The tube is split and there appear to be an outward bulge. Never seen it happen before.
__________________
Mudu93

Please donate to the Mark Reynolds Memorial First Bike Fund at www.markreynoldsfund.org
Mudu93 is offline   Reply With Quote
Old 01-04-10, 01:43 PM   #7
hotbike
Senior Member
 
hotbike's Avatar
 
Join Date: Dec 2006
Location: Long Island, New York
Bikes: a lowrider BMX, a mountain bike, a faired recumbent, and a loaded touring bike
Posts: 2,859
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
File it smooth , and wrap fiberglass with epoxy around it. This way, no heat will affect the temper of the tubing.
hotbike 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 03:28 AM.