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View Full Version : Help with Braze-Ons, please...



Richie Rich
04-27-2008, 12:50 AM
Occasionally, I need to braze on some Braze-Ons but I don't own a torch.
Using the MIG is kinda tricky for such a small part and is a bit overkill for the job.

What I need is the bare minimum setup to do a couple of braze ons per bike without having to buy a complete O/A setup.

Can you suggest a small torch that will do the job? Perhaps a MAPP torch?

I presume bronze rod would be the best for this application.

Thanks..........Richie >>

TheKid
04-27-2008, 01:19 AM
I used MAPP to braise on a cable guide. It took forever. I tried oxy-mapp, which was faster, and I managed to braise on 3 guides, for an extra 8 bucks. (I also presumed bronze rod would be best.) I then tried the golf shafting epoxy I told you about. I held them on with a small squeeze clamp, the kind that are like wrist exercisers, with great results. I left the clamps on for 24 hours. If it's colder than 60 degrees, you may want to let it set a little longer. You don't need much, and wiping the excess is a must. Spread a little glazing compound and fine sand with 400 grit paper after the epoxy sets, to make sure the paint will stick. Also, make sure there is no paint on the braise-on or the frame, and sand both before using the epoxy, even on bare steel. You're right about MIG. It's real hard to get a good job out of it:

http://i192.photobucket.com/albums/z66/edpol_photos/Meridian/000_0062.jpg?t=1209270365The two top ones are from the factory, the bottoms are welded on. (Flux core) The next one was also welded. I don't have any pics of the ones I epoxied on. I did them for a friend.

http://i192.photobucket.com/albums/z66/edpol_photos/Meridian/000_0061.jpg?t=1209270592

Wood Butcher
04-27-2008, 06:34 AM
Occasionally, I need to braze on some Braze-Ons but I don't own a torch.
Using the MIG is kinda tricky for such a small part and is a bit overkill for the job.

What I need is the bare minimum setup to do a couple of braze ons per bike without having to buy a complete O/A setup.

Can you suggest a small torch that will do the job? Perhaps a MAPP torch?

I presume bronze rod would be the best for this application.The best results that I have achieved installing braze-ons has been silver brazing (hard soldering) with a MAPP torch. Bronze rod or brass rod is not really the best choice, IMHO.

First, the bad news... a roll of silver solder wire (not the low temperature stuff sold at the big-box retailers) can be a bit spendy given the price of precious metals these days. It is sold by the troy ounce--unless you have very deep pockets, don't even think about buying a 1/2 lb or 1 lb roll.

The good news...you don't need much to attach a typical braze-on. Try a local welding supply company first for the silver solder (1/16 diameter wire is big enough). If you can't find it locally, it is available from several online sources. One potential product that will do the job can be found here:

http://store.sra-solder.com/product.php?xProd=6131&xSec=19

A good paste type flux is essential to a good silver brazing job (the flux should look like toothpaste). Superior, All-State and Harris all make some very good silver brazing fluxes. My personal preference is Harris Stay-Silv White Brazing Flux.

An acceptable substitute to silver brazing wire is "Sil-Phos" rod and can be obtained from a farm supply store, welding supply company, or a heating/air conditioning supply company (Sil-Phos rod is used for brazing the joints on refrigerant lines).

If you decide to go the route of silver brazing...
make sure that both sides of the joint are extremely clean
remove all traces of paint, dirt, rust, oil and grease; wipe down both sides of the joint with acetone or lacquer thinner
don't touch either side of the joint with your bare hands--the oil on your skin is enough to ruin the job
apply flux to both components in the joint
apply heat evenly
when heated, the flux will first turn white and dry out; when it melts and runs clear apply just a touch of the wire (keep the flame on the joint)
if the joint is hot enough, the wire will melt and flow like water into the fluxed areas
wait for the joint to cool before removing the glassy flux residueHope this helps.

Mike

TheKid
04-27-2008, 02:53 PM
I completely forgot about silver solder. I used it in the 70"s when I worked for a couple of years installing central AC systems. Thanks for the reminder. I would assume that MAPP will take just a little longer to get the job done than acetylene. Silver solder is a goof choice, because it leaves a nice smooth joint. Great advice. Thanks!

Wood Butcher
04-27-2008, 05:46 PM
A couple of things I forgot about in my reply...

A good MAPP torch to use is the Bernzomatic JTH-7:

http://us.st11.yimg.com/us.st.yimg.com/I/onestopshopcatalog_2000_44955851
It has a 3-foot hose between the regulator and torch body. This allows access to some pretty awkward places without having to worry about the gas cylinder getting in the way. It's also good for plumbing work.

Also, do not let the flux boil off from the joint. If that happens...game over, start from square one again. Don't try to re-flux the joint--let it cool down, clean everything and start over. You will probably do this at least once so you will have an idea what to look for and avoid the next time.

TheKid
04-27-2008, 09:08 PM
I use MAPP for plumbing all the time. Much faster and more dfficient than propane, and only a little slower than acetylene. That's a handy item you posted. Holding those tanks can be cumbersome and tiring.

Richie Rich
04-28-2008, 09:03 PM
A special "THANK YOU" to everyone for your input to my question.

One of the greatest features of these Forums is the wealth of knowledgeable people who are here.

I've taken all of your information and filed it in my 'Biker's Notebook'....(a collection of tips and tricks I've picked up along the way).

Thanks again....

.......Richie >>