Bending a fork KOTA style

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Think about the conduit bender...
When you pull back on the bender, your stub of "conduit" will bend upwards. So imagine the tip of your fork as the stub. Now you can slide the bender back towards the head tube to move the inside of the bend further up the fork if you want. I usually get the original bend in the fork tucked right in the curve of the bender, so as I pull up on the bender it bends the orig bend even further. Also less likely to kink that way. Practice on a ratty fork first.
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Carl.
 
Further insights...
Big thanks to @KOTA for making this mod popular. A conduit bender seems like the natural tool for an electrician, but not all of us think like that. Also, fork need to fit inside the "size" of the bender. A large 1" landing gear style fork won't bend in a half inch bender. Does the fork's tubing fit into the bender? If you have bigger tubing than your bender it won't work right. There's different size benders for different size tubing - 1/2" and 3/4" - being the most common. Slow and steady pressure is best. And as usual YRMV.
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Carl.
 
This is the set-up I used for my fork in BO11 (BarellBanana): If you get the big pipe parallel to the axle, it's pretty easy to keep the whole thing straight. Use a long piece of pipe to slide over the head pipe of the fork to get good leverage and go slow, bit by bit.
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Gesendet von meinem K00Y mit Tapatalk
 
I just found a couple of these conduit benders at the scrapyard,i didn't know what they were at first until i googled the serial numbers on them,i just grabbed them because they looked cool to me,lol.
My question is,Can i use the benders to shape out some Fat Bike Forks like in this picture i grabbed from the internet ? Thanks
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See my second post with the hand drawn pic. As long as the tubing/fork fit in the bender it should work. I will tell you it takes some plotting to bend back to back bends for the "U" shape.
Now this will work but....
This is the set-up I used for my fork in BO11 (BarellBanana): If you get the big pipe parallel to the axle, it's pretty easy to keep the whole thing straight. Use a long piece of pipe to slide over the head pipe of the fork to get good leverage and go slow, bit by bit.
f46bc8bd0cf8d1770c966b60d40a9e0a.jpg


Gesendet von meinem K00Y mit Tapatalk
The reason I don't bend and forks or tubing without a bender of some type
(like @SwissGuy 's post) is because of the possibility of kinking. That is what the tubing being cradled in the bender prevents. Now if the tubing/fork can be filled with sand that will help keep it from collapsing too. (I use table salt when I need to do this, it's easy to pour and cheap) But whenever I can I use a bender.

Carl.
 
So basically, the sand or salt acts like a mandrel inside the tube, preventing it from crushing?
I'm not sure mandrel is the correct term, I always think of a mandrel as being solid. But you're thinking in the right direction. I believe it spreads the forces and keeps the tube from kinking, they've been doing it that way for years. Now a bender does act as a mandrel because it doesn't allow the piece to bend out of shape. The tubing has to follow the curve.

Carl.
 
The reason I don't bend and forks or tubing without a bender of some type(like @SwissGuy 's post) is because of the possibility of kinking. That is what the tubing being cradled in the bender prevents. Now if the tubing/fork can be filled with sand that will help keep it from collapsing too. (I use table salt when I need to do this, it's easy to pour and cheap) But whenever I can I use a bender.

Carl.

The kinking was, what I was most afraid of when doing it this way. But if you go slow in small increments and are using a large radius this setup works. But I would not recommend using it on a expensive piece of equipment, as it is a bit of a trial and error approach.. ;-)
 
The plus side of bending both forks at once over a "jig" of some sort, is the uniformity of the forks. Bend them as slow as you want. When there's no mandrel the possibility of kinking is there. The BEST results are when you use a bender. A conduit hand bender, a hydraulic bender, or a tubing roller. Use what you have. KOTA style bends use a conduit bender.

Carl.
 

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