brennie 

I recently bought this early 80s Akisu fork for an MTB project. I was looking at one of the dropouts and it looks like one may need a repair.

Perhaps this is just the old paint but I wanted to get other opinions.

Does anyone else think this dropout needs to be rebrazed? Thanks!

bulgie 

"Rebrazed" impies it was ever brazed in the first place. Well some of it was, but the job was never completed.

I think with some more brazing it can be safe, hard to know for sure though. And getting someone to braze it might not be easy or cheap. Sorry if this fork has sentimental value to you, but it's not very good quality. I think most people would say it's not worth paying for the dropout to be brazed, if you have any other options. Any chance of finding a cheap used fork in your town?

dsaul

It appears that it was never fully brazed to the fork leg. It seems to have held up well with only half of it brazed, but I would want to clean it up and try to flow some more filler in there.

brennie 

That makes sense. It isn’t really sentimental. I could probably fill it in myself, right? I have no brazing experience but could get the job done with a propane torch, some flux, and some filler.

If I took that route, do you have any suggestions? Specifically on the front of what type of filler to use. Thanks again.

dsaul

Propane won't get hot enough. MAPP gas will get hot enough to flow high silver content filler. If you don't already have the filler, it might not be worth buying an ounce of it for this project. 56% is probably a bit too thin for that gap, but System 48 filler works well for things like that.

I'm just a hobby builder, so I would probably fix something like this for a reasonable price. Where are you located?

unterhausen

It's going to be difficult to flow silver into there because you can't clean it properly. I have had luck with brass and dirty surfaces, but that takes a real torch. The problem with not having any experience is that you don't know if the filler has flowed into the joint. I wouldn't bother.

bulgie 

Yes, some DIY-ers have "the right stuff" to figure this out on their own, but most don't. I wouldn't recommend trying it yourself unless you have a mentor to show you some stuff first, and/or inspect it after it's done. Torch safety, personal protective gear etc, how hot is hot enough, these are things an experienced person can show you in a half-hour or less, versus bashing your head against a wall of ignorance. Again, apologies if you're one of those who can just figure this stuff out for themselves (with Youtube), but be honest with yourself. Those people are rare; most who think they're "all that" really aren't.

If you're in Seattle you can swing by my place for a short introductory lesson and maybe just watch me braze your dropout.

BTW, I know I sound like a skipping record, but people asking for this type of advice really should include their town and what country they're in. Without that, we can't advise you on who to go to that's near you.

unterhausen

What PPE do you use? I probably should start wearing a mask when I braze. When I search online for my asthma symptoms, they may actually be COPD symptoms. So brazing/welding is bad news.

bulgie 

I think I was the only one at the frameshops where I worked that ever wore a respirator for brazing, and I didn't always myself. I mostly wore it when I had a long stretch of fillet brazing to do, typically a tandem. For fillet, at least if you're trying to do your best, you need to have your face in the plume of rising fumes part of the time. Without the respirator, I sometimes got symptoms of "brass fever" which is from zinc poisoning. Luckily zinc isn't very poisonous and the effects are (as far as I know) only short term. Though there are a few known cases where it was fatal, those are more likely to be foundry or kiln-related, not from brazing. Effects I felt were mild at their worst, just some slight nausea and headache which go away pretty much as soon as you get to fresh air.

Not like cadmium, in the same family as zinc, one level lower on the periodic table (just above mercury), which stays in you long-term and is very toxic. I'm sure you all know that silver filler rods sometimes contain cadmium, so you reeeeally need to know if your silver has it or not, and if it does, just "keeping your head out of the plume" isn't good enough. Brian Baylis might be alive today if he'd used cad-free silver or if he'd used a respirator, but he was famously one of those "just keep your head out of the plume" guys — that might even be an exact quote. He died of a lung issue, maybe unrelated but I'm suspicious.

I am no expert, but I was led to believe that zinc fumes are actually small particulates, that condensed from vaporized zinc after leaving the vicinity of the flame. They aren't vapor, they're solid. So the correct cartridge is, I believe, a HEPA filter for particulates. That's what I used anyway, and I don't remember ever getting any zinc fever symptoms while wearing one — seems to have worked. I also wore a face shield that covers the intake of the cartridges, so hopefully some of the plume was diverted away from the intakes. No filter is perfect, and they don't seal perfectly against your face, so belt-and-suspenders is worthwhile. And you still should keep your head out of the plume as much as you can, if only to extend the life of your cartridges. I don't know how to tell when a Hepa cartridge is used up, so I just changed them once in awhile.

I had a US Divers brand respirator for years, dunno what happened to it. The one I have now is 3M and seems very good. Availability of cartridges might be an issue, unless the mounting interface is standardized? Dunno, but with a 3M mask you know you'll be able to get cartridges for it. Get a pair of Organic Vapor cartridges for it too, if you ever want to do any painting. Keep your organic cartridges sealed up whenever not using them, I hear they absorb stuff out of the air and get partially used up just from sitting unused, if they're in the open air. Heck even with HEPA cartridges, I keep my mask in a snap-lid clear plastic storage bin, if only so it isn't covered in whatever dust and grit settles out of the air in my shop. Ooh, I should move it, store it next to the striker for my torch so it reminds me to wear it while brazing.

easyupbug 

If the above did not help all I can say is I hope you are in or near a town with a frame builder nearby. I have had repair advice and work done in Salt Lake City many years ago and the same in Tucson twice and was very pleased with the advise, repairs and paint work done.

zandoval 

I saw literally a fork in the same condition a few years ago. Even the same color, Wow. Both the drops outs were in place and firm but did not show decent brazing. Anyway the guy latter fixed it by just taking it over to a local welding shop. He told me the welder brought out a little TIG Welder no bigger then a shoe box and just zapped them there in the back of his truck with a thin wire. The paint was a little burnt but it looked like a real good job. I dont know what filler he used but it was shinny, silver, and was not rusting; almost like stainless steel.

I have seen some detailed Tig welding that was true work of art. And then others that were some abstract chimpanzee made representation of a bad dream. If you do go to a welder then be sure to get one with good hands...

bulgie 

Having a brain would also be a plus.



"Nailed it!"

brennie 

I appreciate the offer but I’m in Los Angeles.

Does anyone know of any framebuilders in So Cal? Thanks again everyone!