Probably a dumb question, but how are people measuring Z movement accurately on the Rong Fu since there isn’t a DRO for the Z axis? For example, I’m not sure how you’d mount a dial gauge / indicator to measure the movement with the way the Rong Fu works with its quill.
Thanks for the help!
The dial control has old-fashioned manual measurement ticks on it, in increments of thousandths, 100 per rotation. Look at it from the right side of the machine. But there are a number of accuracy issues with it, and with z-axis motion on the Rong Fu in general. I can coax 2-3 thousandths accuracy for my final size or depth with some care, but rarely better.
There are some possible ways we could permanently mount a digital caliper on the machine to serve as a poor man’s Z DRO; if someone wants to take that project on, I’ll explain what I have in mind.
Thanks Ethan. I’ll have to take a look the next time I’m there. 2-3 thou is probably good ebough for what I’m doing on the machine. Anything more precise than that and I will probably just use the tormach / some baby CNC machines I have at my place.
More dumb questions, but do you have to worry about backlash on the Z axis as much as you do on the X/Y (if milling without a DRO)?
Also, depending on the cost, I would be happy to help get a Z axis DRO for the machine, if one exists. I can’t remember how much the X/Y DRO was, but I remember it being less expensive than what I would have expected, and I was blown away how fast it was installed (I was the “helper” the day it got installed, although the person I was with that day did 90%+ of the work).
Yes, you have to worry about backlash. You deal with it by always approaching your mark from the same side each time, going back and trying again if you overshoot. That’s how it always was in the days before DROs.
I don’t know if there’s a usable Z DRO for this machine. I know that it isn’t a priority, because we are all focused on activities that will enable us to get a new mill, hopefully within 2-3 months. Once that happens, we can look at giving the Rong Fu a full overhaul and maybe some upgrades.