After the welder dropped of the Gantry ends & legs, I decided to play in the shop for an hour or two!
The two short-frame sections need to be cut to length (60") and have two 3/8" dowel pins and one 1/2-13 threaded hole per end. The spacing of all the holes & pins is critical, less the frame end up as a parallelogram :nono:
So I measured the tubes and found they were 1" too long, and decided the best way to accomplish this is to start in the middle and work outward!
Using a tape measure, I marked the middle of the tube, and drilled & reamed a 1/8" diam. hole at the center point. Next I moved over 24" which is about the max travel on my mill, and drilled & reamed another hole on either side of center.
Next, I placed a gauge pin in the hole and used an edge finder to pick up center of the pin while it was sticking out the side of the tube. Then I moved over 4 1/2" and set the DRO to zero. Now I drilled & tapped a 1/2-13 thread thru one wall. Then I moved over .875 and drilled & reamed the 3/8" dowel pin hole. When finished I pressed the dowel pins in, leaving them protrude about 5/16" Then I repeated the process on both ends of both tubes!
Lastly, I measured and scribed a line at the 30" mark (half the tube length) and band sawed the remaining bulk off!