G0678 CNC Conversion Build Log

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Dave_C
Posts: 884
Joined: Mon Apr 21, 2008 10:34 am
Location: Springfield. MO.

Re: G0678 CNC Conversion Build Log

Post by Dave_C » Tue Feb 13, 2018 10:51 am

Progress Report:

Here is a picture of the front Y axis belt/pulley cover. This should keep the shirt tails out of the pulleys! :D

Spindle encoder is on the way as are the pulleys and the belts for the Z axis and the encoder.

Stay tuned, we'll be right back with a rigid tapping video after this commercial break! Yeah, right. There is still lots to do before I make any holes to tap.

Dave C.
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0213180928 (2).jpg
I learn something new every day! Problem is I forget two.

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Dave_C
Posts: 884
Joined: Mon Apr 21, 2008 10:34 am
Location: Springfield. MO.

Re: G0678 CNC Conversion Build Log

Post by Dave_C » Sun Feb 18, 2018 1:51 pm

Progress Report:

I have the encoder mount almost complete, I just need to put the slots in for the mounting bolts and the three set screws to allow for alignment of the belt. I'm still waiting on the pulleys and belts for the X axis and the encoder.

The encoder mount uses two 10 mm bearings, a shaft made from W1 drill rod with a 10 mm x.300" step on the bottom end, a 8 mm x .400" step on the top and then a 10 mm step below that for the upper bearing. That leaves 1.440" in the middle to mount my 2.670" timing pulley of which there will be an exact match mounted below the 5" spindle pulley.

0218181223 (2).jpg

I also finished the tool change idea that lets me raise and lower the knee as needed to compensate for longer or shorter tools. The way this works is I set my part Z zero with my first tool. After I use that tool and I'm ready for a tool change I make a G28 call and move to my tool change position away from the part. With this .250" dial indicator and the mount I made from scrap, I can establish the height of the tool I set my Z, make a tool change and then just raise or lower the knee till the needle is at zero and I'm back to the same cutting height as I was before but with a different tool length.
0218181223a (2).jpg
So no tool lengths to set in my tool tables, just the tool diameters! I won't have to worry about getting tools back in the spindle at an exact height because I will make a quick measurement on every tool change. It is not as fast as having it all in the tool table but with a little less than 4" of Z travel I needed to come up with a way to compensate for a drill chuck, reamer and other tools that would exceed the 4" travel available.

We'll see how well it works once I get this all done.

Dave C.
Grizzly G0678 CNC conversion with Acorn in progress!
I learn something new every day! Problem is I forget two.

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