Software & Electronics for Mini-Lathe?

[SteveHGraham]

I am working on the parts for my mini-lathe CNC conversion. It's not specific about software and the electronic crap that drives the motors. If anyone wants to make suggestions, I am listening. I don't want to order something listed in the plans and find out everyone else quit using it in 2004.

Cheap is good, but if it will keep me from going crazy, I am willing to spend a few bucks on software I can actually learn to use.

I bought parts to make it work with NEMA 34 motors, since big things are good. Haven't ordered motors yet.

I spent a couple of hours machining a piece of steel for a complicated part, and when I did an "interim" measurement, I found that the length was about 2.400", when I was shooting for 2.450". Talk about bummed. I have no idea how that happened. I think I sometimes lose a digit on the DRO, because it has a totally unnecessary tenths display.

[GlennW]

because it has a totally unnecessary tenths display.

A piece of masking or electrical tape is a cheap fix for that...

Mine has a button to eliminate the display of the fourth digit.

[SteveHGraham]

I really need to learn Chinese.

[sch]

If you are concerned about "2004" tech, you should avoid the controllers that rely on parallel port connection to the computer
and look at USB connected controllers.

[ctwo]

Steve, I think you should keep the machine and it what it can be into perspective.

I've read good about Ethernet and USB controllers (smooth stepper), but I think parallel is still popular. Mach3 is very popular.

Here is how I am setting up my Bridgeport:

XP PC running Mach3
CNC4PC $25 parallel breakout board
5V from PC USB port
Torroidal unregulated 72 VDC 20 Amp power supply
Gecko G203v stepper drivers
Older than the hills NEMA 42 Sigma ~1300 oz-in stepper motors
mechanical limit switches

[ivatt260]

Hi Steve;

I did a little Unimat SL lathe as a CNC lathe. It actually works quite well; did not put the spindle sensors on it (yet?) for threading.

Intel "Atom" motherboard;
LinuxCNC;
it does have a Mesa 5i25 in it, but not configured yet; just using the parallel port;
Gecko G540 (overkill, but I had it, and it's really simple)
48v switching power supply;
home switches (two)
48v relay for the spindle power. (controls the 115v to the spindle motor)

If you want to thread, you need two index pulses to do a 100% accurate job; one once per rev for "top dead centre" and one that gives a series of pulses to indicate spindle position.

On my larger lathe (8x18) I'm using magnetic sensors, quadrature coding, on a 40t gear on the spindle; it should give me 160 steps of spindle position.

Using stock screws is ok, but something with little backlash would be better; maybe the acetal nut idea, where it's moulded to the feed screw - might do this on my 8x18 lathe.

I do have some pics on http://cnc-for-model-engineers.blogspot.com if you want to see what the little Unimat SL CNC is like.

JohnS.

[SteveHGraham]

Thanks for all that info. I don't know what it means, but I'll start looking things up!

[Bill Shields]

NEE-HOW!

[ctwo]

ni hao 你好
you can also say "ning hao"您好 to show your respect

[Bill Shields]

sounds the same, no matter how you write it in English...

nobody seems to object...

[hammermill]

its that g spelling that always gets me.

[SteveHGraham]

I am starting to see that this is not like buying a toaster. I would have thought that after 40 years of CNC, you could just buy four or five things and connect them, but I am the eternal optimist.

Does anyone know if there is any efficient way to feed Alibre projects to a CNC lathe? I can sort of draw things in Alibre.

I don't even know how CNC works. I know the computer tells the motors to go back and forth, but that's about it. I am hoping I won't have to deal with a horrifying interface.