Z feed on a g0704

[vincent52100]

Hi all. I need to make a z axis power feed for my g0704 mill. It’s very hard for me to raise and lower the head. I’m planning on a sprocket and chain to raise/lower the head. I’m not sure what sprocket ratios I need to use, I was thinking of a 4 to 1 ratio but I just pulled that out of the air. Any thoughts would be appreciated.
I’m using a wiper motor from a 2016 Buick La Crosse, about 55 rpm. 6 turns of the Z axis wheel moves the head about 1”.
Thanks!

 

[epanzella]

I'm in the process of building a power head lift for my RF30 clone. I'm using a hi torque low RPM drill motor on the top of the column for power. The lifting will be done by a 5/8 x 11 threaded rod used as a vertical lead screw. The head should go up about an inch per second when done. I'm well along and it should be complete in a few days.

 

[vincent52100]

Please post some pics. Very interested to see it!

 

[hman]

Back in 2016 I added a powered head lift to my Grizzly RF-30 clone, in the form of a "big dish" satellite antenna positioner. These are nice, slow, powerful motors, and have buit-in limit switches. They're getting a bit difficult to find nowadays, but well worth the effort. It's post # 8189, about halfway down page 819 of the thread.

Potd - Project Of The Day- What Did You Do In Your Shop Today?

Spike strip?

www.hobby-machinist.com

 

[bill stupak]

I did mine with timing belt and pulleys from Amazon, and a variable speed pwm and momentary switch.

 

[epanzella]

Please post some pics. Very interested to see it!

Will do. I'll start another thread.

 

[Boswell]

Did you consider a counterweight system or a gas shock system? If so, I am interested in why you ultimately decided to go with a powered solution? Do you plan to drive the z-axis under power during a cut or only to re-position?

 

[macardoso]

Hi all. I need to make a z axis power feed for my g0704 mill. It’s very hard for me to raise and lower the head. I’m planning on a sprocket and chain to raise/lower the head. I’m not sure what sprocket ratios I need to use, I was thinking of a 4 to 1 ratio but I just pulled that out of the air. Any thoughts would be appreciated.
I’m using a wiper motor from a 2016 Buick La Crosse, about 55 rpm. 6 turns of the Z axis wheel moves the head about 1”.
Thanks!

I converted my G0704 to CNC way early on, so I never got a chance to crank the head up and down. I did, however, add a gas spring to counterweight the head. You might want to consider a 50lb spring.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

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[bill stupak]

The 50# spring is a very good addition, powered z axis or not.

 

[hman]

Did you consider a counterweight system or a gas shock system? If so, I am interested in why you ultimately decided to go with a powered solution? Do you plan to drive the z-axis under power during a cut or only to re-position?

OK, a bit off topic, because mine was a different type of mill - a round column (RF-30 clone), not a dovetail column. One of the main reasons I went to a powered system was a side effect of the crank's location on the head, instead of on the column (as with @bill stupak's G0704). Whenever I had to crank the head up or down, the off-axis torque caused the head to gyrate/oscillate around the column by as much as an inch or so in X. Plus the fact that the lock bolts were on one side of the head and the crank on the other - not the best designed user interface in the world. And no, using the powered Z did not preserve the X,Y zero. But it did tend to keep the changes minimal.

PS to Bill - That's a very clean looking installation! I love it.