Motorized milling machine head

[jdurnya]

I have the Grizzly G0704 mill. I added a step motor to the Z by placing a timing pulley under the hand crank and mounted the motor behind the coloum. I can still turn the crank if I want but the motor works fine. I added a couple gas struts, one on each side of the mill and I may now have so much upward force that the harder work is to lower the motor.

I made an arduino controller that does most of what Drew mentions. I did not add a joystick, just push buttons. I have an up and down button, and beside each I have a red button that sets a stop. You can go up to some point, press the stop button and the control will not go above the stop so you can feed down, then just press the up button and it will stop at the preset position. The down control also has a limit position, and when either limit is set a red led is lighted by that button.

I have ramping in the code, and a pot to set the speed, although its not very effective right now, I need to play with the code values a bit more.

In my control box I have two drivers and planned to do the same function for the X axis, as a power feed for milling, but I have not mounted the motor yet. I got distracted by other projects. I will see if I can find the arduino code and post it here, but I will be leaving for the NAMES show so it will be a while before I can do it.

Sorry to take this off topic..

Ron, loved your shop tour on youtube years ago.. would love an update

Joe

 

[Neil Lickfold]

Thanks for the detailed reply, The ball screw really does make sense. On my one it needs a new gib as the one that is in it is bent. When locking it up, the head moves more with the bottom one than the top one. I'm was thinking of adding a centre locking screw , but that is solving the underlying issue. While at it, I'll add some lube channels to the sliding block and link them to a single point oiler, similar to what I did with the X Y oiling and oil grooves.
Neil

 

[ahughes3214]

Thanks Joe, I appreciate the feedback!

 

[ahughes3214]

Neil,

I noted my Z axis gib was also slightly curved. I get the same results as you when tightening either lock down.
I either tighten them a little bit at a time (go between one and the other slowly tightening) or just end up locking one.
For the cuts I make, one lock seems to be sufficient.

Thanks,
Drew

 

[PhilPassmore]

I may have missed another reply saying the same, but a simple addition that can help a great deal and reduce the work either you, or a motor has to do, is use a 'gas ram' of the type typically employed on car tail gates to assist the lift. Cheaply available on Aliexpress.

 

[Jhawk]

My grizzly 7055 has the power lift on top of the column connected to the shaft. It’s similar to your mill. An option would be a pneumatic impact wrench like the shop built ones for spindle nut takeoff) on top of the column. You could still use the crank then. It wouldn’t need the air piston to engage it since the shaft on the column is used only to raise and lower the head and it could stay engaged. Or buy the power unit from grizzly.