Steel shape dimension

[hjsdds]

I am trying to accurately CAD in SolidWorks C3 x 5 hot rolled A-36 steel channel. I have all the dimensions except the flange angle. Someone posted it way back in either degrees or a ratio, I don't remember. There is a tf dimension in the standard (.273 on all 3 inch C-channels) and a Cx dimension.
Not sure how they reference the two, to the start of the radius or what? Also radius is not given anywhere.
I'll be running crown thread wheels (greyhub.com) in the channel and need to know how much "slop" I'll have in the design.

hjsdds

 

[whammett]

You might want to try reposting here

http://www.eng-tips.com/threadminder.cfm?pid=559

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