First Ti build

It’s been something I’ve wanted to do for awhile but never thought i’d be able to. McGovern had given me a bag full of scrap Ti he had lying around the shop and it took me until now to cut them up and melt together. After talking to a few other builders that have transitioned into Ti from steel i just bought the damn tubes and went for it.  What’s the worse that could happen? I had a gap in the queue, the time was there, had some room on the credit card, boom…Ti gravel bike time.

The biggest challenge wasn’t the welding or mitering of tubes, it was figuring out where to get the tubes and creating and troubleshooting my backpurge setup and finally the finish work – chasing the BB threads and reaming the seat and head tubes.  Since i’ve always done the reaming by hand it was a wake up call to try Titanium.  Most cyclists aren’t known for their upper body strength so just trying to take a VERY small amount of material off the inside of the 2″ long seat tube collar was laughably difficult and took way longer than i expected. Didn’t expect to have to wear ear protection either…it sounded like i was strangling a cat in the garage.  Awful! I was sore for a few days afterwards, no kidding.  So now I have plans to set up my lil SB 9a lathe for the finish work on the head tube and seat tube…more on that in the future when i actually do it.

With it being a 650×50 frame for me i didn’t want to tool up too much just in case i wasn’t into it.  Tubing cost is the biggest noticeable difference from steel. Whether you go butted Reynolds or straight gauge from Ti Joe or Dedacciai it’s all at least twice the cost of the most expensive heat treated steel tubing. Getting some 3D printed dropouts you can raise your material costs to more than i’ve charged for entire steel frames until recently.

The mitering was not much different than with steel, I used the same cutters and drill bits that i normally use although I killed a few drill bits since they were already worn.  Ti is uniquely flexible and hard at the same time. You need to hold the piece as close as possible to where you’re coping to minimize flex and ideally have a separate set of cutters for Ti.

Backpurging needs to be dialed in or you risk contamination and cracking. It’s pretty obvious when you don’t have your internal purge set up because any color other than a yellow-ish straw color and you need more argon in there. It’s hard to know what’s happening inside the top tube and downtube though so really should test and cut up tubes to see how it’s flowing before welding up a frame to ride. (I didn’t but hey, it’s my bike and i can do what i want to.)

Welding was pretty similar to steel but with lower amperage and the puddle was more “sticky.” Hard to explain… but the puddle grabbed the tungsten more and the wire gets stuck in the puddle easier especially if you’re dabbing and not pulsing.  Other than that the puddle just flows nicely. It’s like using 880t wire on steel where the puddle wets out and makes for a nice looking  bead, assuming you have your settings set right and the argon turned up high with a big cup.  This was my favorite part, the welding…which isn’t saying much since that’s most everyones favorite part.  But up until this point i was on the fence about Ti, whether i’d continue to do it or not.  After welding the frame i was kinda hooked…it’s a new challenge and there’s no hiding any imperfections under paint or powdercoat. You finish welding and build up and ride!  No paint, no powder required.

I rode it for a week and realized I forgot to order and install eyelets for a rear fender.  Once i got the eyelets I just tacked them onto the dropouts with the wheels still on the bike and boom… now i have a rear fender.  No brazing, soaking, painting, just weld the thing on there.  I like that.

Titanium has a mystique, and it does need to be a lot cleaner than steel with more purge gas, and it’s harder on tools and more expensive to build with, but all in all it isn’t too difficult if you’re already building proficiently in steel and TIG welding it together. It will make you dial in your fixturing and backpurge setups since you can’t use magnets to hold bosses on the frame while you tack, and can’t NOT backpurge. Steel is way more forgiving a metal and I love using  it, but Ti definitely ups your game and makes you look at your process in more detail.

A few parting thoughts…

Ti distorts more than Ti, really need heat sinks while welding and to watch your heat input.  Need to let the metal cool while machining or tapping threads or cutting or you risk breaking taps and ruining the frame.

Don’t bother trying to cold-set Ti. Get your welding sequence dialed and once it’s welded completely it’s done. There’s mythology about certain builder’s tacking and welding sequences that purposely put the frame OUT of alignment only to bring it back into alignment once it’s all complete, and of frame fixtures purposely out of alignment to help do the same thing…but for now that is all down the road for me and this first frame wasn’t that far off from straight for me to worry about it. 

Riding it, i don’t notice what my alignment table told me. It rides like a bike, and the material isn’t incredibly more supple than steel but is quite smooth.  It’s not a night and day difference. A good steel frame rides very well, but will be 3/4-1 pound more in frame weight than a comparative Titanium frame. And that is a lot of weight if you care about that kind of thing. I know i’ll have more ride quality thoughts over time when i get more hours on the bike and compare it to my really close in geometry steel bike but for now the things i notice most are weight, comparable or greater frame stiffness when out of the saddle, but absorbs bumps similar to a heavier and less laterally stiff steel frame. I remember this kinda of feeling when i went from my old Klein Pinnacle which should have been the stiffest frame around (1987 vintage with a Manitou 1 fork) and purchased a used Litespeed Ocoee around 1994…it felt stiffer. When i got a grassroots sponsorship from Moots in ’95 and started riding a YBB i initially felt like i had a flat tire and kept looking down at the rear tire but it was awesome once i got used to it!  Seeing the old shop at Moots was one of those experiences i’ll never forget.  Since then (c.1998) I’ve not ridden a Ti bike going from Aluminum to Steel, a stint with a used carbon Trek 8900, and back to steel.  All have their own feels, pluses and minuses, but I’m of the mind that steel and Ti make the best bikes for what I like to build and how i like to ride. They’re non-disposable bikes that have character and are easily customize-able without a huge investment in tooling or money.

 

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