# What tubing for a segmented fork?



## bobbotron (Nov 28, 2007)

I'm thinking about making a brazed steel segmented fork for fun, for my cross check. I have some ceeway LE13-1 - 26.2mm plug dropouts, so I'm going to use 1 1/8" OD tubing, but I'm unsure of what tube thickness I should go with. I'm about 190 pounds, and am pretty easy on gear... Given that the plug is 26.2mm, I think I'd have to go with a 0.035" walled tube, but that seems a bit thin. Alternatively, I could go with thicker material and file out the ends so the plugs fit...


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## Live Wire (Aug 27, 2007)

You'd probably be fine with .035 if you are as easy on stuff as you say, but .049 would make the fork bomb/jump/crashproof.

ps, you don't file tubes down- file the drops to fit.


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## Walt (Jan 23, 2004)

*Use .049"*

I built some .035" x 1.125" tubing forks at one point (maybe 10?) and I can tell you that it's not a great idea. I built some by accident when I first started making forks (I wasn't measuring the butted tubes I was using and got a messed up batch - always measure the butts!) and had to recall them from the customers after they started breaking. Probably had to rebuild 10+ forks. Luckily nobody was hurt. I still have a nice pile of unsafe forks sitting in the corner of the shop gathering dust.

I *never* use less than .049 for 1 1/8" segmented forks now. And of course, I measure the butts before I start building anything, duh.

If you're doing a cross fork, why not use a smaller blade with a thicker wall? The TT Kit-FB4 and Kit-FB-7 are both nice, depending on how light you want to go.

If you're looking to go lightweight and 1 1/8", use a .035" or .028" blade and a 1.25" sleeve on the top where the crown attaches.

-Walt


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## bobbotron (Nov 28, 2007)

Walt said:


> I built some .035" x 1.125" tubing forks at one point (maybe 10?) and I can tell you that it's not a great idea. I built some by accident when I first started making forks (I wasn't measuring the butted tubes I was using and got a messed up batch - always measure the butts!) and had to recall them from the customers after they started breaking. Probably had to rebuild 10+ forks. Luckily nobody was hurt. I still have a nice pile of unsafe forks sitting in the corner of the shop gathering dust.
> 
> I *never* use less than .049 for 1 1/8" segmented forks now. And of course, I measure the butts before I start building anything, duh.
> 
> ...


Thanks Walt, I appreciate it. I think I'll try it with 0.049" straight gauge tubing. I'm not worried about weight. What do you use for the piece that connects the fork blades to the steer tube? More 1 1/8"?


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## Walt (Jan 23, 2004)

*Yes*

I generally just match the diameter of the blades. You can get away with thinner crown pieces (ie, .035" would work) but the weight savings is so small it's not really worth it. I generally use .049".

Good trick: if you're using the TT OXPLATMSRDLT steerer tube (the 1.2/1.6 one) you can cut off 4 inches or so of the top section (which will still leave you with plenty of steerer for the fork) and use that to make the crown. Works great.

-Walt



bobbotron said:


> Thanks Walt, I appreciate it. I think I'll try it with 0.049" straight gauge tubing. I'm not worried about weight. What do you use for the piece that connects the fork blades to the steer tube? More 1 1/8"?


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## Smokebikes (Feb 2, 2008)

.049", Great info........Thanks for sharing! :thumbsup:


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