1954 International Norton - a couple of questions

G'day Simon, all wideline f'bed frames were SIF bronze WELDED, not brazed.

"Fillet brazed", and "Sifbronze welded" are synonymous. There's no sweat brazing on a featherbed, so I reckon by "brazed" he meant not arc welded.

Interesting story. Hadn't heard that before and I use the stuff every day. It doesn't stick to stainless steels though. Gotta use nickle silver rod or any of the new high strength, silver filleting alloys for that, depending on the strength required.
 
Many years ago, I could have bought a heap of old Manx racing stuff which included 3 SOHC engines. So I did not buy them. SOHC could not possibly be as good as DOHC ? One day my 500cc Triton got blitzed by a 500cc DBD34 BSA. 'Beauty is in the eye of the beholder '? - It is easy to underestimate potential.
 
G'day Simon, all wideline f'bed frames were SIF bronze WELDED, not brazed. Here is the story about SIF Bronze. SIF Bronze. Suffolk Iron Foundry After outgrowing their original premises and moving to a new 6 acre site, the Suffolk Iron Foundry were approached by a young experimental engineer to supply cast-iron rods containing extra silicon for use in welding cast-iron with an oxy-acetylene flame. Following this, Louis learned of the techniques of low-temperature bronze welding for cast iron which inspired him to develop a rod, which subsequently was found suitable for welding virtually any metal except aluminium. Using the initials SIF from Suffolk Iron Foundry and adding ‘bronze’ the Sifbronze technique was born.
The Wideline Featherbed frames used on Dominators & ES2s were not bronze welded, but manual metal arc welded using steel filler rods.
 
G'day Simon, all wideline f'bed frames were SIF bronze WELDED, not brazed. Here is the story about SIF Bronze. SIF Bronze. Suffolk Iron Foundry After outgrowing their original premises and moving to a new 6 acre site, the Suffolk Iron Foundry were approached by a young experimental engineer to supply cast-iron rods containing extra silicon for use in welding cast-iron with an oxy-acetylene flame. Following this, Louis learned of the techniques of low-temperature bronze welding for cast iron which inspired him to develop a rod, which subsequently was found suitable for welding virtually any metal except aluminium. Using the initials SIF from Suffolk Iron Foundry and adding ‘bronze’ the Sifbronze technique was born.
Do you know when this appeared? Reading the history books I have on the Velocette, i recall a concern back in the early '20s or '30s of hyrdogen embrittlement from welding of frames. I think that issue was very much in the minds of metal workers due to it being linked to the Titanic hull failure. Velocette frames were always brazed right up until their demise in 1971.
They also had their own front fork design post ww2, which had steel sliders with steel cast lower brackets, held together with tin mans lead based solder. Not sure why these were not brazed. The solder develops hairline cracks after decades and needs sorting to stop oil pressure leaks.
 
How common is this? I have never encountered this problem but only have one velo with the velo forks so I may have just been lucky.
Common enough to have FishTail articles written about the corrective action needed. My 1st Velo, '54 MSS, owned 1 yr, has oil leaks (since acquiring bike) at the casting to slider joint that I've just spent past week fixing (hopefully).

EDIT:
Here is one procedure recommended to me from the guys on the Velocette Technical forum over on Groups.io and it what I have done to mine as a first try (as it saves having to re-paint the sliders/castings: as with a full re-solder job):
 

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Common enough to have FishTail articles written about the corrective action needed. My 1st Velo, '54 MSS, owned 1 yr, has oil leaks (since acquiring bike) at the casting to slider joint that I've just spent past week fixing (hopefully).

EDIT:
Here is one procedure recommended to me from the guys on the Velocette Technical forum over on Groups.io and it what I have done to mine as a first try (as it saves having to re-paint the sliders/castings: as with a full re-solder job):
This is good to know. Thanks.
 
In Australia, the best frames are bronze welded using in-line flux. Rod Tingate used to work for Colin Seeley in England, he uses that technique and so does my mate. On the frame my mate made for me, he used flux-cored nickel-bronze rods. Frames which are arc-welded, probably need stress-relief heat treatment. Japanese frames don't seem to crack, but the tube gauge might be much bigger - their steel frames are heavier ?
 
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