# Sherline CNC Lathe



## deedubs (Oct 30, 2011)

Is anyone using a Sherline CNC lathe to automate production of wood pens?  If so, has it resulted in increased efficiency over hand turning?  My guess is that the turning itself may not be that much faster, but it would free up a set of hands to work on other aspects of production such as drilling, gluing, and finishing?  

Thanks,
Dave


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## rherrell (Oct 30, 2011)

Seems to me that you wouldn't have time to do much of anything before it would be time to put in another blank. Besides, why do you want to "mass produce" them, you can go to Staples for that!:biggrin:


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## workinforwood (Oct 30, 2011)

The Sherline CNC will pump out a pen barrel slower than you can do it by hand, but there's lot's of other benefits it would offer, like repeated precision, and automated threading.


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## studioso (Oct 30, 2011)

You can't thread on a sherline cnc. You'd need the special gears on the back for that: but that's not a cnc function
The advantage would only be repetition and precision
.


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## bitshird (Nov 2, 2011)

studioso said:


> You can't thread on a sherline cnc. You'd need the special gears on the back for that: but that's not a cnc function
> The advantage would only be repetition and precision
> .



Sure you can thread on a CNC lathe, easy programing steps, and a feature of most CAM software.
you only need the extra gearing for manual threading. But I agree whymass produce them, you'll never be competitive with the stuff from China!.


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## studioso (Nov 2, 2011)

bitshird said:


> studioso said:
> 
> 
> > You can't thread on a sherline cnc. You'd need the special gears on the back for that: but that's not a cnc function
> ...




as far as I'm aware, you can only thread if you have a cnc controlled 4th axyz. on the lathe, the cnc can only control the saddle's movement, not the rotation of the main motor's spindle (the spinning material).

I have a sherline cnc mill with 4th axys, and a cnc lathe. honestly I barely had any time to learn how to use them in CNC mode, but if indeed you are correct, please let me know!


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## mredburn (Nov 2, 2011)

Sherline even states on their website that it cant be done on their lathe with the supplied setup.  THe ones that I have seen that can thread with sherline lathe setups add a control panel with an encoder on the spindle to  control the spindle speed.


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## bitshird (Nov 2, 2011)

mredburn said:


> Sherline even states on their website that it cant be done on their lathe with the supplied setup.  THe ones that I have seen that can thread with sherline lathe setups add a control panel with an encoder on the spindle to  control the spindle speed.



Mike, I thought the lathe spindle speed was infinite on the Sherline?? and isn't there a threading canned cycle in Lazycam on Mach-3


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## mredburn (Nov 2, 2011)

The spindle speed can be varied but they dont have a controller that can measure the rpms or control the speed. It does however have about a 50-70 rpm bottom speed. The Spectra light machine (which uses Sherline lathes)I have has an encoder belt driven by the spindle shaft and it feeds back to the controller to allow adjustment of the spindle rpm in relation to the other two axis.  The gears for threading lock the feed screw to the spindle. Im not sure if it would mesh with the stepper motors so both would turn at the same time. And the gear set up is not adequate for anything other than hand threading. The arm that holds the gears likes to kick out disengaging the whole thing under modest pressure. THere is no real lube to the setup since its out in the open. A lot of the older Spectra light machines are bieng converted to Mach 3 by adding the encoder and a 10v power supply.and the board to control the motor.

I dont know if the canned cycle in Mach 3 will work on the lathe the way it comes setup. I havent really looked at it. I will go take a look shortly.


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## workinforwood (Nov 2, 2011)

I woulda thought it could easily do threading too. Regardless what the speed of the spindle is, if you can get it down to 70 rpm, you control the bit, so you jump in, race across and jump out with your cross slide. But hey..I don't know anything about the sherline lathes. I know my mill will do threading or tapping or dieing. It's pretty simple, you just need a diameter, a length and a pitch and a depth. I guess buying a sherline lathe is out for me.  I am not that impressed with their machines anyhow, I think the motors and the pulley's are weak. I've seen stronger rubber bands in my wifes hair than the belts on those machines.

There's the point about drilling too. You say the lathe will free up time for you to be drilling, but doesn't the sherline do that too? If it can't thread and can't drill, what else is there, just x,y motions for a tool bit?


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## mredburn (Nov 2, 2011)

Most threading is not done in one pass. There has to be a way to accuratly measure the spindle speed to make sure you have the proper tool travel to get the proper pitch. When you make your second or third or more pass through the material it has to start in the same place. Thats why they lock the spindle and the feed screw together with gears. It will drill but the lathe was not designed for large projects. A 1/2 drill bit is taxing the design. It was made for miniture hobbyiests and it works well for what it was designed for. I have never broken the belt cutting with it but the one im suing currently has a kevlar toothed belt drive not the V pulley system.


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