More of my learning on machining...

I was going to machine a channel on the front plate for the rails to sit on. The machining of the first tile went great. But when I machined the second tile, the depth of the pocket was not the same as the first tile! Nooooo! So I tried the 3rd tile. The same thing! I had the plate sitting on stand-offs because I was also drilling. I thought that I might be having problems with the pocketing because the plate was not sitting flat on the stand-offs or the stand-offs were not even. I finished the drilling and then took the plate off the stand-offs and set it on the tooling plate. My tooling plate is supposed to be flat to 0.003".

I tried the first tile and then the second tile. The same problem - the pockets for the first tile was not the same depth as the first tile! What's going on! Then I noticed that the plate was not sitting perfectly flat on the tooling plate! Oh! I removed the plate and saw that there were some chips on the plate. Argg!. Cleaned up the chips and make sure the plate is sitting flat. No, it wasn't! Double Arrgggg!

The gantry plate is against 2 locator pins on the side and another index pin in the center. I also drilled another hole in the center for my clamp. I was only using a single clamp on the center to hold the gantry plate down. Now I put 2 clamps each on each side where each tile ends. This time, it looks like the gantry plate is sitting flat. Try again. Success! While I can see where the first tile ends and the second tile begins because of the tool swirl marks, I cannot feel any ridge.! Anyway, I was going to have a 2mm channel that ended up as a 3mm channel but I'm happy with the result. Lesson learned.

Finished products shown in pictures below.

I will talk about my rail cutting experience in the next post.