Quote Originally Posted by NordicCnc View Post
JAZZCNC, if you read this I have a question for you. How do you go about assembling the L-shape gantry together? I have received my aluminium profiles and to my surprise I noticed that they are not flat in the middle. It is probably hard to see in the picture but it is about 0.5mm.

I was thinking that I could sand it down, since the only critical thing would be that it is flat on the sides so that it wont wiggle when assembled.
I've never seen profile made like that.? If that picture is showing it correctly it looks like a flattened pyramid.!! . . . The profile I use is always flat but if there are any slight highs or lows I just shim the rail to suit.