Correction + CNC progress

Forgive me, I seem to have overlooked a major thing, I won a test indicator NOT a dial indicator. There is a difference, the test indicator functions as a "finger" and can be used inside holes. The Dial indicator is very sensitive to direction of setup. A finger indicator you press on from the side. I can't believe i didn't think much of it and simply "knew" what i was looking at was what i wanted, and had all the features i was looking for.

CNC progress report:

Troy and I made substantial design decisions again. I did some calculations based upon the rail and carriage dimensions determined the usable travel on the rails we are "suspected" to get. I bought one of the rail sets with the 'buy it now' feature on ebay. This included 2 used rails, and SR20 blocks from THK. Got it for 100$. We are waiting on two more rail sets to finish the deal. I really hope we win them, because if not i'll have to redo calculations. For our z-axis i'm going for some HSR carriages to ensure they can take the forces on the head.

Using the dimensions of the rails, I calculated the theoretical range of ballscrews we needed to make the most use of the rail travel. We sent off the request for these appropriately sized ballscrews to our "supplier" more info on this later.

We started to evaluate what kind of steppers we want for our setup. It looks like the 282 oz-in steppers will yield a max driving speed of 73.82 ipm. (We had to assume that the max pulse frequency is 10000 pulses per second based upon the specification chart http://www.kelinginc.net/KL23H276-30-8BT.pdf ) To do the calculations was a bit annoying because the charts we had were based in pulses per second. Using the microstepping ratio we were able to compute the approximate RPM's at a given pulse rate. Using the generated torque's on the specification chart we can compare it to the required torque for a cut a specific feed rate.

With all these calculations I've decided to start writing a program to make the process easier to repeat, and manipulate the variables for design considerations. I'll put that up later.