Making your own Ti springs

Discuss light weight issues concerning road bikes & parts.
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Boonen
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by Boonen

Popawheelie; I'm planning the work on my front der. right now and am reading through your old posts. I was wondering if you heat the Ti to make it easier to bend or does the temperature have to be to high for Ti to make that work? I have bent steel before and heating it is the trick to make it easy. Your Ti springs look very nice so I was just wondering.

Also, did you (consider) replacing the steel pivots that are in the main aluminium body itself (the part with the limiting screws) I was thinking about replacing the steel nut in there and maybe drilling the massive steel rod. Any thoughts on this would be appreciated!

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JDZ3QJ
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by JDZ3QJ

hello, my method of homemade is easier. no need plier, no need clamp. You just need new 2 bolt and a wooden plank. On the left side is the work done by 30 seconds. 8)

Image

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Boonen
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by Boonen

JDZ3QJ, can't see your picture :noidea:

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twistyaction usa
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by twistyaction usa

Boonen wrote: I was wondering if you heat the Ti to make it easier to bend or does the temperature have to be to high for Ti to make that work? I have bent steel before and heating it is the trick to make it easy.


Don't heat it. To get it hot enough to be easier to bend, you'll permanently weaken it. Bending it at room temperature will make it a little stiffer, so maybe you can get away with using less and still have the springing force you require.

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ebsilon
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by ebsilon

Boonen wrote:JDZ3QJ, can't see your picture :noidea:


here you go :D

Image

Ciao ebsilon

popawheelie
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Location: in Colorado

by popawheelie

I don’t heat up the ti when I make it. I have heard that heating it would stress relieve it. Ti wants to return to it’s original state. So the spring could get tighter over time. But I don’t think it’s an issue.
The springs I make now are less (4) winds. Since they have less winds they aren’t as uniform in tension throughout their travel. There is more tension on the spring when the chain is on the big ring. It work out great because that is where the spring has to shove off the chain.

The original steel spring needs 4.9 kg of force to make it work. Mine takes 3.5kg. I think 4.9 is to much. I check all my springs for this tension before they go out on the 41 gram derailleurs I tune for fairwheel bikes.
I push the steel insert out and replace it with an aluminum one I make. I change the hole so there is a 7* taper. The insert I make has the same. You could glue in an aluminum nut there. I do the same for the pinch bolt that holds the cable.
I drill out both of the steel posts in the body. I stop just shy of going through but I don’t see why you couldn’t go all the way through. I think a lot of holes in stuff looks a little tacky, but that’s just me. Be careful not to bugger the threads on the one.
There is no Ti or steel on my derailleurs now. Just aluminum and carbon.
You can see from the pic that there are only 4 winds.
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Boonen
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by Boonen

Thanks a lot for sharing your wisdom popawheelie :thumbup:
I will try with 4 winds of normal 2.0mm titanium rod, it doesn't have that colouring but it looks like that would work as well. I have no idea how you determine the tension of a spring like this but I will just go by trial and error on this one and see how it works out :D
JDZ3QJ, I can see your picture now (thanks ebsilon!) looks like a good way to make these as well.

popawheelie
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Location: in Colorado

by popawheelie

Since I'm making them for other people I have to have standards that i can go back to. I made a mount for the derailleur and attached weights to a string. I just measure the weights.
Once I set it up it's not that hard.
2.0 rod should be fine.

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PalleRaa
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Location: Denmark - Copenhagen

by PalleRaa

Here there is only talk about Ti springs for Campa FD. Has anyone made a ti spring for a XTR FD or RD?

/PalleRaa

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divve
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by divve

I faintly remember something about the XTR/DA RD springs already being ti....

mike
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by mike

PalleRaa wrote:Here there is only talk about Ti springs for Campa FD. Has anyone made a ti spring for a XTR FD or RD?

/PalleRaa


hi, check you pm....

popawheelie
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Joined: Thu Sep 26, 2002 3:42 pm
Location: in Colorado

by popawheelie

As it works out the Campy front derailleur is the best for tuning. You want to start with the best you can get since you are doing so much work.
But the rear is another story. I've spoken to Madcow about the rear derailleurs and he suggests the Shimano.
We haven't really gotten into rear deraillleurs so maybe the Campy has potential. Madcow has done some tuning to the Shimano rear.
I've gotten one request for a tuned Campy rear but haven't done one yet.
That was from someone who doesn't like Shimano.
For some people a Campy front and a Shimano rear is unthinkable.
But that might be the lightest way to go.

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Boonen
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by Boonen

@popawheelie; There is a thread over in the DIY section of the fairwheelbikes forum where Jason says that they did investigate tuning a rear derailleur to sell in the shop, but with all the work involved it would be more economical (and lighter as well) to just buy the new Lightweight derailleur instead. But ofcourse for people tuning their own stuff this isn't a concern :D

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