What material for a DIY rail for Biesemeyer fence?

I've finally decided to go ahead and make a new fence mounting rail so I can use my Biese fence on the Grizzly G0691. I can get steel or aluminum tubing in the correct size. Steel in 3/16" wall, and Aluminum in 1/4" wall. Would the Aluminum be strong enough and hold up as well? Or will it flex when the fence is clamped down? Steel would be about $10.00 cheaper and would probably tap better for mounting bolts. Thanks for any insights you may have! Jim.

Jim,
I've been cruising the web for the last week looking at aluminum extrusions for a project. There is an amazing amount of info out there about this stuff. Here are some of the resources I found. Maybe they will help you choose.
http://familywoodworking.org/forums...e-of-Extrusions&highlight=aluminum+extrusions
https://www.youtube.com/watch?list=PL671DEB1C05E2AD96&v=OhZ5Mo9ma2U
http://vsctools.com/diy-guide-rails/
http://vsctools.com/aluminum-extrusions/
http://openbuildspartstore.com/v-slot/?sort=bestselling
http://www.8020.net/Default.asp
http://www.ebay.com/usr/8020inc

Thanks Ted! Some good info there. I've decided to go with the steel, but maybe find a thinner wall. Just not sure if I can tap threads into the thinner material and it still hold well. I usually over engineer, though.
Have a great Christmas! Jim.

I'd go with steel - and you'd never wish you'd gone thinner ... i'd stick with thicker walls to get more threads. Aluminum may be fine but I think it'll scratch and ding easier and it WILL flex more than the steel (enough to matter? not sure). Steel's cheaper, holds a thread much better, and is accurate to the original make. I'd stick with that and definitely do the 3/16 wall.