Welding of a "new" FCC Titanium frame

[bonsaii]

Howdy!

Like the nerd I am, i bought the FCC titanium frame parts on ebay the other day. The seller announced them here.

In the package came:

- Bottom bracket with serial number (094T3XS)
- Bottom bracket wreck (machined to wrong OD and to little thread)
- Dropouts. Left side 2 off, right side 2 off (plus not machined material for an other set)
- Dome/end caps for chain stays 4 off
- Tripple cabe stops 4 off
- Single cable stops, small 18 off
- Single cable stops, large 6 off
- Rear cantilever cable stop (new type) 2 off
- Studs for rear canilevers 2 off
- Unknown studs, mabye for fork..??
- Unknown support, Square plate w. inside threaded stud.(Chain suck plate support??)


First I bought them for my collection, but now I'm seriously concidering to send the parts back to the US to get them welded.This parts must be attached to some tubes in a specific geometry...!

My wet dream is to have one from the Sommerville days to perform the work and complete the frame.

-bns

[jbrannsten]

Cool parts, even though they might never being built up.

I don't know how many of the Somerville workers that is still active building frames. Christopher Igleheart is one of them and Mike Flanigan being the other that I know of.

I don't have any experience with Mike, and I don't know of any who has either. Chris on the other hand has done work for me and you have seen the great results yourselves.

[fat-tony]

I am thinking that Scott Bengtson (I-ROBOTon this site) was the only welder at FCC that handled the Ti frames. You may want to shoot him a PM or something for more info. The crux will be finding those double walled tapered seat stays.

[bonsaii]

Thanks!

Double walled tubes? Hmmm.. Are'nt the tubes on the Titanium Fats externally machined, hence the tapered seat tube- and stays..? My Titanium Fat has monostays, so I'm not quite sure how the "Yo"-geometry Ti Fat tubes are made.

Originally Posted by fat-tony

I am thinking that Scott Bengtson (I-ROBOTon this site) was the only welder at FCC that handled the Ti frames. You may want to shoot him a PM or something for more info. The crux will be finding those double walled tapered seat stays.

[AB]

It's a pipe dream IMO, but Rody and/or Scott may be able to point you in the right direction. I would say a custom frame using these parts would be considerably more expensive than a current ti frame from IF, Moots or 7.

[fat-tony]

Originally Posted by bonsaii

Thanks!

Double walled tubes? Hmmm.. Are'nt the tubes on the Titanium Fats externally machined, hence the tapered seat tube- and stays..? My Titanium Fat has monostays, so I'm not quite sure how the "Yo"-geometry Ti Fat tubes are made.

What I meant was a mistake in terminology. The later Ti's had machined tubes in lieu of sleeves. So if you wanted a new Ti frame based from the later Sommerville Ti's the crux would be in finding those type tubes (for what that is worth).

[bonsaii]

Thanks again!

Okay, the parts is for the later Sommerville Titanium Fat construction, no doubt about that. In my simple mind I thought these were standard tubes, "of the shelf" at any decent construction material dealer, that FCC externally machined to the correct OD, WT and tapering. I will investigate this further..

Originally Posted by fat-tony

What I meant was a mistake in terminology. The later Ti's had machined tubes in lieu of sleeves. So if you wanted a new Ti frame based from the later Sommerville Ti's the crux would be in finding those type tubes (for what that is worth).

[bonsaii]

No doubt, AB, this is a "dream" project that may well stop itself.. I did'nt think finding tubes should be the key. I thought the biggest challenge would be to find a welder with a frame jig, belive it or not..

Originally Posted by AB

It's a pipe dream IMO, but Rody and/or Scott may be able to point you in the right direction. I would say a custom frame using these parts would be considerably more expensive than a current ti frame from IF, Moots or 7.

[I-ROBOT]

Hello folks

Hey bonsaii - Very ambitious to say the least!!!! The tooling that I made for welding all of the TI parts would be the most difficult and expensive to replicate. I made a water-cooled purgable bottom bracket heat sink out of copper that was used to minimize the distortion in the BB shell since so much heat is concentrated on that particular part. In my opinion, titanium is not difficult to weld, it's EXPENSIVE to weld (even more expensive if you ffff it up!) I had lots of trick little fixtures for brake mounts and cable guides that not only positioned the parts correctly, but also helped shield the hot TI from atmospheric contamination. I wish I had a picture of the BB heat sink, that was one of the coolest tools I made. I also made a "poor man's orbital welder" using a positioner that worked like a small lathe and a custom box that the tube end fit inside. This is how I welded the pointed end caps to the SSs and the CSs. I had a similar set-up for welding the head tube inserts and the seat tube insert. I also had a 1/4" thick copper plate that I clamped to the dropouts while I welded the stays. Simple but very effective. I also built a custom trailing shield that clamped onto the nozzle of the TIG torch that I used when I welded the chin gussets. I also had copper inserts for the head tube and seat tube. Titanium was awful to ream to size so we really tried to keep the welding distortion down on the head tube and seat tube. The noise was incredible.

Another difficulty was cold-straightening. The TI frames would not bend quite as easily as the steel frames and we broke several early on. We went as far as putting another granite block in the weld area and I would clamp finished frames on it and hot-straighten them by rewelding small areas. It is nearly impossible to keep a frame clamped in a large jig and be able to access all of the areas that have to be welded. It is much more efficient to weld the frame on the bench and then put it on an alignment fixture and hot-straighten it - especially TI.

The early tubes were sleeved since butted TI tubes had not yet been made by any of the tube companies. Chris then came up with the idea of machining the tubes on a lathe - very time-consuming and expensive. They sure did look nice though!!

I know Merlin experimented with chemical milling to lighten tubes up as well but I am not sure if they did that in production. I believe that butted TI tubesets exist now but I have been away from the business for quite a while and have not kept up.

If you're serious about "replicating" a FAT TI, I would suggest just finding a butted tubeset.

Hi Tony - glad to see you're still around. I haven't been to AL in quite a while.

Looking forward to spring

Good Luck - it was cool seeing all those parts again.

Scott Bengtson

[ti-fat-man]

this thread needs a picture...

i love this topic...

[bonsaii]

Whaow!

Thanks for the detailed description of the procedure and the tubing specks. Interesting reading about your special tools and copper devices.. Are there no pics of this cool equipment?

I'm no welder, so the idea is to have a specialist to perform the work. Now, I understand that to replicate a Titanium Fat the early FCC style is very hard, if not impossible. I can't pay for making all that cool handmade stuff you had... Without having you to do it, anyways..

I had a chat with a man working at a titanium dealer here in Norway and he actually had a titanium frame made in Sweden. He could obtain the tubing for the job, but your information on the butted titanium tubes is new to me, so I have to dig some more.

Thanks for the cool story, Scott! Darn cool!

bst rgds,
arne

Originally Posted by I-ROBOT

Hello folks

Hey bonsaii - Very ambitious to say the least!!!! The tooling that I made for welding all of the TI parts would be the most difficult and expensive to replicate. I made a water-cooled purgable bottom bracket heat sink out of copper that was used to minimize the distortion in the BB shell since so much heat is concentrated on that particular part. In my opinion, titanium is not difficult to weld, it's EXPENSIVE to weld (even more expensive if you ffff it up!) I had lots of trick little fixtures for brake mounts and cable guides that not only positioned the parts correctly, but also helped shield the hot TI from atmospheric contamination. I wish I had a picture of the BB heat sink, that was one of the coolest tools I made. I also made a "poor man's orbital welder" using a positioner that worked like a small lathe and a custom box that the tube end fit inside. This is how I welded the pointed end caps to the SSs and the CSs. I had a similar set-up for welding the head tube inserts and the seat tube insert. I also had a 1/4" thick copper plate that I clamped to the dropouts while I welded the stays. Simple but very effective. I also built a custom trailing shield that clamped onto the nozzle of the TIG torch that I used when I welded the chin gussets. I also had copper inserts for the head tube and seat tube. Titanium was awful to ream to size so we really tried to keep the welding distortion down on the head tube and seat tube. The noise was incredible.

Another difficulty was cold-straightening. The TI frames would not bend quite as easily as the steel frames and we broke several early on. We went as far as putting another granite block in the weld area and I would clamp finished frames on it and hot-straighten them by rewelding small areas. It is nearly impossible to keep a frame clamped in a large jig and be able to access all of the areas that have to be welded. It is much more efficient to weld the frame on the bench and then put it on an alignment fixture and hot-straighten it - especially TI.

The early tubes were sleeved since butted TI tubes had not yet been made by any of the tube companies. Chris then came up with the idea of machining the tubes on a lathe - very time-consuming and expensive. They sure did look nice though!!

I know Merlin experimented with chemical milling to lighten tubes up as well but I am not sure if they did that in production. I believe that butted TI tubesets exist now but I have been away from the business for quite a while and have not kept up.

If you're serious about "replicating" a FAT TI, I would suggest just finding a butted tubeset.

Hi Tony - glad to see you're still around. I haven't been to AL in quite a while.

Looking forward to spring

Good Luck - it was cool seeing all those parts again.

Scott Bengtson

[bonsaii]

Thanks!

Nice of you to decorate the thread!!

Cheers, mate!

Originally Posted by ti-fat-man

this thread needs a picture...

i love this topic...