Motorized crossfeed

Mighty clean looking installation!
 
Resurrecting an older thread, I thought it might be helpful to anyone wanting to make this project to view this video. Stefan Gotteswinter is an amazing machinist and puts out really good videos. His project titled "Quill Feed" is similar to PT Johansen's. Between the two, there is a wealth of information. Makes me want to get into the shop right now instead of pecking on a keyboard. :)

 
Amazing is a indeed a word that could describe what Stefan does in his home shop. It's well worth a watch.
The precision and accuracy he routinely achieves, I can only dream of.
There is indeed a strong resemblance between the design in this this topic and Stefans video. Simply because the video posted above, inspired me to adapt the design to a crossfeed mechanism. The initial idea came from Stefans video.
 
Brilliant work on that. Is the release mechanism, button pulled out really necessary? With the stepper with motor off it will free wheel and then manual control will be possible, no need to disengage.

Stefan has nice machine work on the project but again if he used a stepper none of the work on the shaft would be needed. Engage and disengage with the stepper (Or servo) power on or off. I have a servo on the quill like that on my Rong Fu 31 and with power off it is free to move manually. Instead of pulling out the lever just turn on the power and it engages. On Stefan's setup he needs to disengage physically because the motor he has will not free wheel when off because it is a gearbox.

I do really like the mechanism of the push button lever though.
 
Cadillac STS said:
Brilliant work on that. Is the release mechanism, button pulled out really necessary? With the stepper with motor off it will free wheel and then manual control will be possible, no need to disengage.
Click to expand...

You are absolutely correct, there is really no need for the "manual override". When the power is off, the motor can rotate freely.
There are however a few reasons why it is included.

1. It increases confidence. Being able to pull or push a lever, in plain sight, to avoid disaster, is for some people a big thing.
Those electronic pixies can do anything when not looking;)

2. Regenerative power. If the motor is always engaged it will probably generate power when driven manually.
Most stepper drivers have motor protection diodes to avoid power feedback from damaging the electronics. But I can't promise that all possible drivers have this. Therefore a manual disconnect.

3. The feel of manually turning the handle changes when the steppermotor is connected. The smooth continuous feel is replaced by a jagged motion of turning the stepper motor. It almost feels like the crossfeed has steps in the leadscrew.
Ofc the stepper motor could be exchanged with a DC motor, but they tend to be long and thin, not fat and short, there isn't much room to play with.

Other than that, there is absolutely no reason to include a mechanical disengage.
 
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Love it! I actually hate engaging the gear train to drive my cross slide. This solution may actually be better!
Robert
 
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