So, Mike, the rule means "flatted wire" or more appropriately "D" wire is out, unless it's only on the bottom.
On the D3 site you can see what Warmack has done on his "Twistamon". He has had other issues with that car getting it into an IRRA™ legal state. Issues I won't have, other than this one...
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I could post a pix of mine (once I leave work, can't download camera phone pix here ...). I understand what it was allowing, but it's excluding all flat wire (OK by me) and some
D wire applications that several people are using.
I'll be playing with flex also. And as the NW is on the cusp of adopting a set of Retro rules, we want to use a set that are "friendly" to experimentation. This rule, as written, is a stumbling block limiting some creativity.
I do not use a "mill" to do this, I use a mill file. and takes me about 10-15 minutes to flatten .078" rails down to .0625" while I'm building the frame. Future tuning on cars with or with out "D" wire will dictate I use the same procedure. I just want to make sure all is right with the world... first.
(And not have to pull rails out to flatten them.)Thanks.