CNC conversion to Lagun Knee Mill

[D. Kent]

Hello friends, Happy New Year.

I am curious if there are any members here that have converted their manual Lagun mill to CNC for X-Y? I've been slowly gathering parts, doing homework, and curious if anyone here has done so or purchased one already converted?

Cheers.

 

[D. Kent]

Small update with this project: I found a used Millstar setup, just the mechanical components, but enough to get started. This includes the belt / pulley / motor mount housings along with a Y-axis screw. I can't use the short Y-axis; it's for a 9"/12" travel. I see if I can't get some photos of the parts / pieces. From what I can tell, definitely appears the bolt patterns are identical between the kit components and my Lagun. I do not know what brand machine the kit was originally on. My first issue with the kit will be the dated hole pattern for the motors; they don't appear NEMA standard. So, there might be some challenges to find modern motors (not the original Glenteks) that fit the existing motor mount pattern without modification.

I've been sourcing ball screws and debating using AC servo motors (vs. DC Steppers). The price for reputable AC's is rather expensive compared to steppers, but there are some cheaper AC alternatives.

This is on my old FT-1 with the basic 9"X42" table; which is all I need for my garage.

 

[pontiac428]

You probably won't find NEMA on older stuff, the standard was originally published in 1998. It's also a predominantly North American standard.

Luckily, bolt patterns and flanges are among the easiest things to adapt.

I would not consider steppers on a full size knee mill. The value of an encoder vs. a limit switch cannot even be compared. Servo torque is superior. Steppers run hot by design and develop low torque at low speeds. Look at the status quo, steppers are great on plasma cutters, router tables, and 3d printers. No- to low-load applications, higher traverse speeds. Mills, especially mills that stand on the floor, are never, ever seen as commercial products with steppers- they are exclusively servo drive machines. CNC VMC mills the same. Probably something to it.

Edit: The servos will be what they need to, but I really like Gecko drives. Their servo drive is serious, more of a high-reliability component than the junk on Amazon.

G320X Digital Servo Drive | DC Brushed Servo Driver

The G320X is Geckodrive's digital DC brushed servo driver. Rated up to 20A & 80VDC with a small footprint high performance. Made in USA & ready to ship!

www.geckodrive.com