View Full Version : Hello from Cornwall - Rong Fu 25 Conversion

29-09-2009, 01:41 PM
Hello All,
I've recently inheritied a Rong Fu 25 mill/drill in good condition and couldn't resist the temptation to convert it to cnc. So far I've got the mill up and running and bought a system 4 kit from http://www.diycnc.co.uk.
The kit only arrived yesterday so I've only just built the system 4 main board and will start on the driver boards this evening.
I've been looking around the internet for bracket ideas to neatly fix the motors to mill. So far the best I've seen is at http://www.silverkatt.co.uk/cncmillsystem/ but I'm open to suggestions. I'm planning to do the basic conversion and then think about improving backlash but I like the idea of maintaining the ability to use the hand wheels so ball screws may not be appropriate. I've seen something where the standard nuts have been replaced with acetal / delrin but I've no idea how effective this modification actually is.

30-09-2009, 09:05 PM
Hi Jason,

I am considering the same/similar mod to my Warco Minor MD30 which is very similar.. Other members here have done similar conversions to other mills of a similar nature, look for posts from Robin Hewitt and Bill Todd for example.

John S
30-09-2009, 10:10 PM
This is how we do the X3 conversions.


That square block contains two angular contact bearings and the coupling. This one has had the double shaft cut off the back of the stepper but It could have been left for a hand wheel.

01-10-2009, 11:26 AM
John, that's the neatest solution I've seen so far. I certainly bear it in mind but as I've already got the motors, they're single ended and I'd like to get some confidence with the conversion and operation of a cnc mill before I lose the hand wheels I'll try a bracket and belt arrangement first.

Just finished building all of the system 4 boards so hopefully I should be able to look at plugging everything together this weekend to make sure I haven't made any mistakes with my soldering and the motors turn. I'm sure I'll start making some brackets within seconds of the checking the electronics.


This bracket for the z-axis looks the easiest solution so I'll copy that idea to begin with. I'm still undecided about the x & y bracketry but I like the idea of enclosing the belt and pulleys as I'm sure they're bound to get covered in chips and coolant otherwise.

01-10-2009, 08:27 PM
I have some drawings which I did of the JS (JohnS) motor mount system as I knicked the idea off of him and can say it works very well.

Don't wont to post them though until John says its ok as I don't want to piss him off anymore than I already have! :whistling:

John S
01-10-2009, 08:59 PM
Post them if you want but anyone who can't work that lot out from the picture is a moron.


01-10-2009, 09:58 PM
Lets wait until someone asks then....