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Terry’s SS silver brazed kick ass road frame

Terry’s SS silver brazed kick ass road frame

bicycle, brazed, columbus tubing, custom built bicycle frame, custom built hard tail street frame, custom frame, custom tips, hand built bicycle frame, hand built custom bicyles, lugged, machinery, primate frame, tools, Welded, Wet Sprayed, workshop0 comments

this is Terry’s stainless tubed frame .

Terry came to me looking to get a titanium tubed road frame but as I explained to him , I have been playing around with TI for a little bit now just getting to know the medium and welding up small pieces to teach my self how to work the metal but I was not confident enough with the material to offer it out as a frame just yet. To this end I had been reading up on the new SS tube sets that where out there and I soon found out that the specks of the SS tubes where on par and in some cases better than titanium and they can be silver brazed so I would be able to work with the welding medium that i specialize in and if all the data sheets ran true have a very light and lively rust free frame at the end of the things.

After talking Terry threw his options and drawing up his frame in cad we came up with the final design which was a pretty easy task as he had been fitted up by Steve hog from Cycle fit and there was only a few mechanical changes to the design that need to be made.

I was a little apprehensive with this tube set as I knew from the specks that it was very very hard and SS is a tricky material to weld with it behave very differently when heated, and being on the very expensive side of the tubing price chart I was defiantly steeping lightly with this one.

the first problem  I encountered was mitering the tubes, I have some very high end silver brand machined cutters That I use for very light and aero shaped tubes they are dead true and very expensive, With SS you have to use a lot of coolant and a slower cutting speed to stop excessive heat build up that will destroy the cutter and work harden the tubes making then even harder to cut and work .With this in mind I spent a lot of time setting up my mill to get everything running correctly, the first cut gave me an idea of how hard this material  is .The stuff is unbelievable each cut was done with a prayer and held breathe but I got thru them all till I was on the last cut. I was all set up with a brand new cutter all going well till it broke the surface and there was a very loud bang  not the sound I wanted hear and I figured that was the end of that tube. after stopping the machine and dropping the table to inspect the damage I was very surprised to see the tube un harmed , I’m thinking score lucky break there But as I cleaned the cutter to my horror I see 3 teeth missing from my brand new $360 cutter. I was having a bit of trouble coming to terms with this, the tube I was cutting has a wall section of .7 of a mm the cutter has a wall section of 2.5mm and is hardened and ground! I knew the tubes where hard but this blew me away.

Though I was bummed about the broken teeth on the cutter one of the main reasons I chose these cutters is that they can be reground with new teeth so I thought sera sera ill just have to get it re cut but on closer inspection i found a hair-line crack running the full length of the cutter “F#%@’ $360 gone in under a min welcome to the wonderful world of  high temper tubes.

After switching to another cutter I very carefully finished cutting the tube .

With the tube set cut and dressed it was onto the next challenge the welding.

Thin walled high temper tubes are always  a challenge especially when they are silver brazed  . Controlling the heat between the different wall section tubes yet making sure that there is enough heat for a solid molecular bond between the material’s  whilst working up  the fillet and making sure not to burn of the silver flux has taken me a lot of years to master, through into this mix the very quick heat transfer of the SS tubes and I was kept on my toes gluing this  frame together.

Terry wanted a frame that was classic but not to old school l so I went for a good mix of fittings to this end giving the frame the small touches that really give a hand-built bike its individual character.

the last thing was a custom SS logo done it Terry’s initials but in the end I was concerned that the amount of heat that I would have to put into the frame to fit the badge was going to upset the welds and there was a real chance of it distorting the thin-walled tubes and putting the frame  out the alignment.

Well the frame is of at star enamelers weighting for its turn in the line up to get sprayed, Terry is still working out his color scheme but at last count it was looking like a hot red with wight  panel , what ever way the color ends up this will be a very hot looking bike.

I’ll put up some shots of the frame and bike when it’s all done .

Stay upright Tarn.

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