Road Fork with Discs - Minimum Wall thickness?

[Will Neide]

I'm hoping to build a lugged road fork with disc brakes and I'm just wondering if there are any recommendations for minimum wall thickness. I intend to make it straight blade and I haven't decided if I want round, oval, or aero legs yet. Ideally, I'm thinking round tapered legs, but am open to options at this point.

[Andrew R Stewart]

From what I read the fork blade's ability to resist bending is the priority with a disk brake. Seems that the blade diameter is a greater factor then wall thickness is. Andy.

[Dallas Tex]

get you one of these, and forget about wall thickness. Great dude Wes Williams from Austin designed it & PMW makes it.

BK2009.jpg

[Will Neide]

That's perfect! Thanks!

[anon.]

For road/cx discs, I like using a mismatched set of KIT-FB4 and KIT-FB7 blades with (obviously) the heavier blade on the tab side.

The Willits tab is a PITA with a tapered blade.

[Andrew R Stewart]

I thought I read some posts about the bending moment just traveling further up the blade when a disk caliper mount has a stiffening tang. Also road crowns have been mentioned IIRC. Andy.

[Mark Kelly]

I thought I read some posts about the bending moment just traveling further up the blade when a disk caliper mount has a stiffening tang. Also road crowns have been mentioned IIRC. Andy.

I did an analysis of bending moments in the fork when I converted an off the shelf carbon fork for disc mount. Either I'm wrong or the authors of the posts you mention are. Since I've still got my teeth, I think it is they* who are wrong.

*For the grammar nazis: the verb to be is a verb of identity so it takes two nominative cases.

[edelbikes]

For road/cx discs, I like using a mismatched set of KIT-FB4 and KIT-FB7 blades with (obviously) the heavier blade on the tab side.

Just make sure you don't invert both blades just before tacking (you know, when you remove everything from the jig to clean and flux...). It doesn't work well at all ! Don't ask me how I know...