Welding cogs
#1
Thread Starter
Senior Member
Joined: May 2006
Posts: 75
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Welding cogs
Yeah... so half a week ago i made a thread questioning if I stripped my cog/hub. I most definitely did. Luckily my hub had 2 fixed sides... so I just flipped it and stupidly put my cheap cog back on my hub.
Last night I was riding a bit fast and had to swerve and slowdown to avoid a road block (I didn't have my light, and a student organization blocked off the road in order to practice pushing a bobsled/luge/death trap up the streets) and as I mashed my legs down to skid, I felt the cranks "slip"-- just like they did when I stripped the other side. I'm 90% sure I stripped the 2nd side of the hub.
I'm a poor student but a student with access to facilities. I'm not too interested in paying more money and investing more time into having my back wheel rebuilt (although I got it built by a local guy... I doubt he'll take pity and do it for free-- but he might not charge labor..)
Would it be possible to MIG or ARC weld the cog to the hub? Both sides are stripped/useless-- I could probably salvage the lock ring and just weld the thing like there's no tomorrow.... but would it actually hold? I've welded chairs and stools (like 3 years ago) and they seemed to hold up pretty well. Anyone have any experience with this?
Or are my fixed gear dreams over?
Last night I was riding a bit fast and had to swerve and slowdown to avoid a road block (I didn't have my light, and a student organization blocked off the road in order to practice pushing a bobsled/luge/death trap up the streets) and as I mashed my legs down to skid, I felt the cranks "slip"-- just like they did when I stripped the other side. I'm 90% sure I stripped the 2nd side of the hub.
I'm a poor student but a student with access to facilities. I'm not too interested in paying more money and investing more time into having my back wheel rebuilt (although I got it built by a local guy... I doubt he'll take pity and do it for free-- but he might not charge labor..)
Would it be possible to MIG or ARC weld the cog to the hub? Both sides are stripped/useless-- I could probably salvage the lock ring and just weld the thing like there's no tomorrow.... but would it actually hold? I've welded chairs and stools (like 3 years ago) and they seemed to hold up pretty well. Anyone have any experience with this?
Or are my fixed gear dreams over?
#4
if he has a cheap enough cog it might be aluminum. or if you can find an al. cog to replace it, would be cheaper than building the wheel.
edit
this is the only al. cog i can find.
https://cgi.ebay.com/EURO-ASIA-ALLOY-...QQcmdZViewItem
edit
this is the only al. cog i can find.
https://cgi.ebay.com/EURO-ASIA-ALLOY-...QQcmdZViewItem
#10
okay, so, i've had that happen to me - "i'm pretty sure i just stripped my shiznit" - but you should definitely take it apart, clean and check the threads. it could slide without stripping, and you should check.
and then you should throw that cheap cog away and get a dura ace cog, cause $20 isn't too much to spend to be more confident that you won't eff up your hub.
capisce?
and then you should throw that cheap cog away and get a dura ace cog, cause $20 isn't too much to spend to be more confident that you won't eff up your hub.
capisce?
#11
Senior Member
Joined: Jul 2006
Posts: 424
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From: Baltimore
You can't really weld ferrous and non-ferrous metals together. At least not for things that have to be structurally sound. You'd be better off trying to braze them together, but you'll probably just melt the aluminum.
#14
Pull off the freewheel part and braze it together or LB weld. All kinds of ghetto but it could work.
__________________
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
#16
Originally Posted by roadfix
Speaking of welding, is there any way to weld or lock my Campy-compatible freehub body on my old Spinergy wheel?
BTW, the Fixxer thing from Surly only works with Shimano freehubs.
BTW, the Fixxer thing from Surly only works with Shimano freehubs.
https://www.fixedgeargallery.com/arti...anula/freehub/
also crimson karter claims to have just drilled a hole in a freehub and stuck an old key in there. i'm not sure of any of the specifics beyond that, but you might want to pm him.
#17
DC's Stray Cat
Joined: Aug 2006
Posts: 207
Likes: 0
From: Alexandria, VA
Bikes: Gary Fisher Single Speed; Raleigh Conversion; Cayne Uno fixed
I did it with a cheap alex rim with quando hub. stripped the sucker bad. Took Jb weld and coated the threads on the hub and spun the cog on. Then put a coat of jb weld around the outside of the cog where it meets the hub facing out. let it cure for a day or 2 then ride. Mine held up for about a month until my new wheelset came in then I took out the axle, cone nuts, ect. for future emergency use if needed and threw the wheel away
#18
Originally Posted by dirtyphotons
well, you've probably seen this but just in case:
https://www.fixedgeargallery.com/arti...anula/freehub/
also crimson karter claims to have just drilled a hole in a freehub and stuck an old key in there. i'm not sure of any of the specifics beyond that, but you might want to pm him.
https://www.fixedgeargallery.com/arti...anula/freehub/
also crimson karter claims to have just drilled a hole in a freehub and stuck an old key in there. i'm not sure of any of the specifics beyond that, but you might want to pm him.
__________________
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
#19
I'm finding it hard to believe a thread can be stripped by pedalling backwards. Were you using a lockring? If not, is it not possible your cog just unthreaded itself?
Guys such as Chris Hoy put about 550 watts through their pedals from a standing start and never strip cogs. Locking a wheel with your legs needs only about half that wattage.
An old aluminum Dura Ace or Zeus cog might possibly strip - I've seen a tooth ripped off an aluminum cog.
Guys such as Chris Hoy put about 550 watts through their pedals from a standing start and never strip cogs. Locking a wheel with your legs needs only about half that wattage.
An old aluminum Dura Ace or Zeus cog might possibly strip - I've seen a tooth ripped off an aluminum cog.







