Would you braze your own fork?

[Pelican]

Just picked up an old Bottecchia frameset from the 80's since it was a bargain. The fork crown and steerer tube had a clean break and nothing looks bent. I was going to clean up the contact area and reweld it. Then I thought I could take the opportunity to a) update to a threadless steerer tube and b) learn how to braze.

http://farm8.staticflickr.com/7413/10280498906_8b26d75fea_z.jpg (http://www.flickr.com/photos/70476053@N00/10280498906/)
broken fork (http://www.flickr.com/photos/70476053@N00/10280498906/) by Pelican_Racing (http://www.flickr.com/people/70476053@N00/), on Flickr

I'm sure I could TIG weld it in also, but have always wanted to build my own frame and this could be the first small step towards that. I've also got some singlespeed drop outs, but they were for a MTB and the seat tube doesn't line up perfectly.

Cheers,
Hong

[choke]

I might well give it a try if it was mine but I do know how to braze. I'd be most concerned about getting it square in the crown. I don't think I'd be brave enough to try learn to braze on a fork though - that seems to be asking for trouble.



And this is just my opinion, but a threadless stem on an '80s bike is just wrong.

[Steve in SLO]

When I learned to braze, I started with cable guides and downtube shifter bosses.
You may want to try a few of these types of things before going for something structural.

[echelon_john]

Whomever brazed the steerer to the crown also probably brazed the blades. So if the crown failed, I'm not sure how excited I'd be to fix that and keep riding it.

[pbarry]

When I learned to braze, I started with cable guides and downtube shifter bosses.
You may want to try a few of these types of things before going for something structural.

^^ This. A fork is the most important structural component on a frame, and has no redundancy if a failure occurs. Do not tig the parts back together. That fork was probably brass brazed and over heated, (unless it was in a head-on collision), leading to the "clean break".

[ultraman6970]

Seen that fix several times, just heat the crown to get the old piece of tube off the crown fork... clean really well and braze the new steering tube. If you know how to braze the fix is really straight forward.

Go

[RedRider]

Go ahead and give it a try but, before you go for that test ride, make sure your health insurance is up to date possibly your life insurance too...

Sarcasm aside... buy a new steel fork that meets your specs and ride with confidence.

[thirdgenbird]

And this is just my opinion, but a threadless stem on an '80s bike is just wrong.

You will hate my answer.

I wouldn't braze may own fork. I would buy a wound up.

[jtakeda]

Short answer, no.
Long answer, hell no

[pbarry]

Seen that fix several times, just heat the crown to get the old piece of tube off the crown fork... clean really well and braze the new steering tube. If you know how to braze the fix is really straight forward.

Go

Did you read point b from the OP?

Then I thought I could take the opportunity to a) update to a threadless steerer tube and b) learn how to braze.

If brazing in a new steering tube is not done correctly, (quickly and efficiently), the brass bonding the blades to the crown will melt away. A fork repair is not where to learn how to braze. YMMV

[Hank Scorpio]

I don't think I would repair an already broken fork but I have brazed my own replacement. With some supervision it is pretty straight forward.

[parris]

What most of the others said. The fork is so critical to safety it's not a place to learn. Also given that the joint failed the first time there's just no way to be sure the rest of the assembly is in any better shape. If you want to learn to braze start with smaller projects that aren't as likely to hurt you if it fails.

[Louis]

Heck no, and nor should you. (unless you know a good orthodontist)

[choke]

You will hate my answer.

I wouldn't braze may own fork. I would buy a wound up.Actually, that's the only carbon fork that appeals to me aesthetically. But I'd still take a steel one any day. :)

[rcnute]

As I understand it brazing in a new steerer is a pretty skilled undertaking (and most recommend just building a new fork).

Ryan

[rice rocket]

Sounds like you're more comfortable welding. I'd save your experiments for something less critical.

[Peter B]

Just picked up an old Bottecchia frameset from the 80's since it was a bargain. The fork crown and steerer tube had a clean break and nothing looks bent. I was going to clean up the contact area and reweld it. Then I thought I could take the opportunity to a) update to a threadless steerer tube and b) learn how to braze.

http://farm8.staticflickr.com/7413/10280498906_8b26d75fea_z.jpg (http://www.flickr.com/photos/70476053@N00/10280498906/)
broken fork (http://www.flickr.com/photos/70476053@N00/10280498906/) by Pelican_Racing (http://www.flickr.com/people/70476053@N00/), on Flickr

I'm sure I could TIG weld it in also, but have always wanted to build my own frame and this could be the first small step towards that. I've also got some singlespeed drop outs, but they were for a MTB and the seat tube doesn't line up perfectly.

Cheers,
Hong

Umm...how 'bout I just give you my old frost white Serotta steel fork instead.

[ultraman6970]

For the record, if something happens the fork wont fail that bad because the brake caliper bolt will keep the thing in place, worse case scenario the thing will get nasty lose or will start creaking because was not brazed right, just saying because I have seen failed forks held but the brake only.

The only forks I have seen fail really bad had been the ones in vitus and alans. In steel you always have the chance to catch them before or even during the problem (held by the bolt).

As for if i read point B, actually did thats why I said if you know how to braze, I wont tig that...Not saying it wont hold but the bronze needs to penetrate all the way inside the socket and I dont thing that tig or mig can do that (may be wrong, not too familiar with the methods)



Sounds like you're more comfortable welding. I'd save your experiments for something less critical.

[Pelican]

Umm...how 'bout I just give you my old frost white Serotta steel fork instead.

This might be the best answer yet!

And thanks for the concern guys, I've built a few things before (http://bitly.com/prong).

Cheers,
Hong

[rice rocket]

What'd you braze on that?!

[Doug Fattic]

Hong, conveniently for you I'm a Paceliner that has been teaching bicycle framebuilding classes since 1976 so I have some idea of what it takes to make and repair frames. You've got an impressive background in making things. Wanting to build your own frame is a worthy goal but starting with a damaged fork is not where I would want to begin. If you want to repair your fork you should have someone that is an expert show you exactly how to do it. It is not the place for a trial and error mistake. I wouldn't describe the process as difficult if you know what to do but it does require a certain amount of specific knowledge and skill.

In my framebuilding classes, I go through a certain logical progression of teaching how to braze starting with what equipment works best, what brazing materials to use, and general brazing principles. Including in that instruction are common rookie mistakes and how to avoid them. Then we start with a simple exercise that illustrates brazing motions. Once the basic principles are learned, the specific choreography of how to do each joint of a bicycle frame can be shown.

One thing that should be obvious is that if one wants to be really good at something they are going to want instruction from someone that is not only very good at it too but also good at explaining how it is done. Some people like yourself will start a lot closer to the goal line than others but the best at something most likely learned from the best. There isn't a week that goes by I'm not thankful for the opportunity I was given to have learned from a European master.

[Keith A]

Not exactly the same, but I thought this was a cool repair of a fork needing a longer steerer tube...
https://www.youtube.com/watch?v=HNbJ9dadNYo

[buldogge]

We have used this method on Vespa and Lambretta forks a bunch of time...to modify length, swap vintage steerers to modern disc forks, etc.

-Mark in St. Louis

Not exactly the same, but I thought this was a cool repair of a fork needing a longer steerer tube...
https://www.youtube.com/watch?v=HNbJ9dadNYo

[Pelican]

I'm not looking to do this on my own. We've got lots of talented builders here in the Bay Area and I would learn by watching, or just have them do it.

Having said that, I'm probably going to bid on a chrome fork on eBay or piss off the purists and get something carbon. I'm just going to build up a little townie with style, so the Campy headset and BB will probably go in the old parts bin.

Cheers,
Hong

[binouye]

For me the answer was "no", for the list of reasons given buy others already. I've brazed 4 frames and ridden them all (still ride 2 of them multiple times every week). But I bought forks for all those frames.

[pbarry]

I'm not looking to do this on my own. We've got lots of talented builders here in the Bay Area and I would learn by watching, or just have them do it.

Having said that, I'm probably going to bid on a chrome fork on eBay or piss off the purists and get something carbon. I'm just going to build up a little townie with style, so the Campy headset and BB will probably go in the old parts bin.

Cheers,
Hong

Beautiful trike you made. Yowza! :hello:

Look up Bernie Mikkelsen in Alamada, one of the best all around builders I've known, (he taught Joe Breeze, back in the day). Bring your broken fork, and he'll make short work of fixing it. The conversation will be worth the price of admission. :)

[Peter B]

I'm not looking to do this on my own. We've got lots of talented builders here in the Bay Area and I would learn by watching, or just have them do it.

Having said that, I'm probably going to bid on a chrome fork on eBay or piss off the purists and get something carbon. I'm just going to build up a little townie with style, so the Campy headset and BB will probably go in the old parts bin.

Cheers,
Hong

Hey I was serious when I offered to give you my old Serotta steel fork.

[DY123]

I used to ohh and ahh over Italian frames from the 70's and 80's. in fact my first real race frame was a Bottecchia in 1980. I must have just stared at it for 100's of hours.

After I got a chance to see many of them deconstructed I realized most of that allure was a stylized romantic image I created. Hand built frames of today are built to a FAR higher standard than factory bikes from that era.

Look closely at that fork. It isn't a break. The steerer pulled out of the crown. You can still see the brake hole in the steerer. Also look at the brass. Do,you see any? I don't. (I can't see the best picture, but it looks like just little bit at the bottom. Probably the same amount up at the top.

For sure not proper penetration according to modern standards, but someone probably rode this 10, 20, who knows how many years none the wiser and loved the ride. Makes me think I way over engineer things compared to the guys that made these frames.

[oldpotatoe]

Go ahead and give it a try but, before you go for that test ride, make sure your health insurance is up to date possibly your life insurance too...

Sarcasm aside... buy a new steel fork that meets your specs and ride with confidence.

Make sure you have a good dentist also. What he said, breaking a fork is always a bad thing.

[Pars]

Didn't they used to shove a piece of wood broom handle up the fork just for this reason? I think I have seen it on a french frame or two...