Primary Frame Finished

I made some solid progress over the end of the week. I finished all of the primary frame (tube parts), and got the long strips that support the X-axis fixtures finished and mounted. I spent a lot of time getting holes spotted (using a mill) in the aluminum angles that go on top of the strips. And, my friend who has been helping me with the use of his shop and machining experience worked on making me a tap for threading the anti-backlash nuts. I have a couple more pieces of steel to drill (all Z-axis components), and a bunch of aluminum stuff to make.

I developed a little bit of a technique to deal with error in a bracketed frame (which I'm sure is nothing new). When I had my long strips ready to be mounted, I loosened a few of the brackets on the cross-pieces so the tiny gaps in the holes of the brackets could reposition on the smaller tubes. I mounted the long strips with the ability to very slightly tweak the distance between the larger tubes. After the strips screwed down securely, I re-tightened all of the loose brackets.

I did have to file down about 1/16" off the end of one of the cross pieces to give it the necessary play (it was maybe 1/32" longer than spec, anyway). Since my brackets weren't machined to any great degree of precision, I simply drilled the holes larger than the screws, and let the varying in bracket attachment take up any error. So far, the machine is as square as I can measure with a square and ruler.