Unusual mig finish.

[God mode restorations]

Hi everyone.
Guys I have came across this picture of a custom bike frame..but what I find really interesting is the finish..is this mig brazing? What are the differences in mig welding and mig brazing..I like the copper looking appearance. Is it stronger or weekend than a normal weld.

 

[overload]

That is Tig brazing.

 

[MCKDAVID]

sure it's TIG? I think I recognize that frame, XR69 and I seem to remember it was done with gas and an inline fluxer.. going by memory, so could be wrong.

 

[overload]

My memory was playing tricks with me! All explained in the thread below.

http://www.mig-welding.co.uk/forum/threads/using-silicone-bronze-with-tig.37923/page-3

 

[arther dailey]

Way back just after dinsours when I had an escort mexico mk1 , had a 4 into two into one manifold, cracked several times, re welded by pro s, got fed up with it so asked the boss if I could use gas bottles in the dinner hour, brazed it up myself, never cracked again. love gas brazing, no clue what rods but its a sweet job in my opinion. Arther

 

[gordon stephenson]

Regardless of the process, it doesn't look nice to me, Looks like the brass is virtually laying on top of the metal.

 

[pedrobedro]

Regardless of the process, it doesn't look nice to me, Looks like the brass is virtually laying on top of the metal.

That's what it does, brass can't penetrate steel as it's different metal.

 

[gordon stephenson]

I do understand, done lots of conventional brazing, which is really designed to flow into the joint between the tubes,plates etc

 

[arther dailey]

I am with you on that Gordon, no flow...cold joint

 

[dannyp]

probaly like motorport tig welding tiny pritty bead done with about 1 amp

 

[God mode restorations]

My memory was playing tricks with me! All explained in the thread below.

http://www.mig-welding.co.uk/forum/threads/using-silicone-bronze-with-tig.37923/page-3

Awsome..just interested in the process and how it's done...cheers.

 

[jordan1]

Looks terrible to me, can't see this 'cold weld' being as strong as a normal mig weld.

 

[BrokenBiker]

Looks terrible to me, can't see this 'cold weld' being as strong as a normal mig weld.

its not a weld, its braze, completely different metallurgy and when done properly brazing is very strong...i doubt it would have been chosen for a motorbike frame if it wasnt strong enough

 

[PhillipM]

Someone better tell Ariel to stop sticking their frames together with it then.

 

[paceman1]

brazing is more flexible but not as strong as a tig weld or mig weld

 

[gordon stephenson]

Still looks cold to me, brass maybe bonded to the surface of the steel most likely not flowed into the joint itself.

 

[PhillipM]

brazing is more flexible but not as strong as a tig weld or mig weld

Theoretically a perfect braze can be stronger.

 

[PTvor]

Theoretically a perfect braze can be stronger.

Why do you say that? I'm not challenging what you say, I just want to know.

I thought that brazing, like soldering, involved an alloying process where the top few microns of the metal dissolved in the braze and formed an alloy. With welding the filler metal and the surfaces to be joined all melt together, which can cause obvious problems if the metal being joined had heat treatment which could be upset and other problems.

I'd have assumed that welding was stronger, but brazing is pretty strong and has advantages, such as being better able to tolerate flexing. From memory, the MOT specifications forbid brazing within 7cm???? of a structural element.

 

[the snooper]

Still looks cold to me, brass maybe bonded to the surface of the steel most likely not flowed into the joint itself.

Don't know what's been used to get that look it I'm with you no way that's as strong as it should be and it's ugly

 

[dannyp]

i thought the reason for brazwing tube frames was to use less heat, less distortion and not upseting fandango steels. tho i'm sure it should look better than that tho