# Power Z axis for RF45 /ZX40A mill



## Abowie (Sep 5, 2020)

Because of lack of space in my workshop it is an effort to reach and adjust the main Z axis feed at the left of the column.

I'm considering fitting a power feed to this for convenience.

Before I make myself something, has anyone already done this, or are there parts available out there to do this easily.

Cheers,


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## TomS (Sep 5, 2020)

Abowie said:


> Because of lack of space in my workshop it is an effort to reach and adjust the main Z axis feed at the left of the column.
> 
> I'm considering fitting a power feed to this for convenience.
> 
> ...



Here's a couple of pictures of the Z axis power feed on my Enco round column mill.  The motor (12VDC) is for a RV slide out that I had on hand.  It's a gear head reduction type.  IIRC I get about 50 rpm on the output shaft.  I power it with a battery charger.  

The motor is direct coupled to the head riser drive mechanism.  I removed the riser handle and fabbed an adapter and coupling.  The hole in the side of the adapter is so I can access the coupling set screws. 

I know of no kits or parts for this type of conversion but that doesn't mean that they are out there.

Good luck.


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## Abowie (Sep 5, 2020)

Thanks David. That's probably what I'll end up doing.


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## Abowie (Oct 5, 2020)

So I bought a 25:1 worm drive transfer box, a 0.09kW 240v AC motor and a fancy switch and did it myself. AU$500 in parts.

I machined up a spacer block out of 25mm ally plate to mount the transfer box.

I had originally intended to mill a keyway in the pinion shaft, but decided it was easier to make an adapter than to disassemble the mill head.

Making the adapter was complicated by the shop telling me that the gearbox had an 8mm keyway, and providing me the stock, but the keyway actually being 5mm.

I decided to use 4140 for the adapter because I only had around 3mm wall thickness to hold the 2 grub screws (hard to see underneath in the picture). I didn't factor in how much harder 4140 is than mild steel and managed to wreck an 8mm 4 flute end mill..

This wasted some hours. I eventually brazed the key stock into the groove in the adapter and filed it to size. Neanderthal.






The hardest part was tightening the 4 Allen screws that hold the incredibly badly designed input flange to the mill body. As you can see here for the trial fitting they are not tightened.. as they are pretty much inaccessible.






Working out how to wire the single phase motor so that it could be reversible took a bit of time and some research. But it works a treat.

I just need to tidy the wiring a little (need a piece of 5 core wire) and it's done.

Thanks for the help and advice!


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## Abowie (Oct 5, 2020)

One difficulty I had was working out how to wire the motor.

I used a single phase, single capacitor 240V AC motor. I used a proprietary forward/off/reverse switch.

This is the wiring diagram.


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## Abowie (Oct 23, 2020)

I've been using this for a few weeks now and it is great.

So much easier to use. Well worth the effort and the cost.


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## Abowie (Nov 3, 2020)

An update.

I've bought this model steam engine kit PM Kit and started making it.

Can I say that with the power Z axis things are so much simpler.  With this tiny model I'm forever changing from a drill chuck to an ER32 or an edge finder and being able to lift and lower the Z for all of these changes is fantastic.

I'd highly recommend this mod to anyone!


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