# Sherline CNC



## glycerine (Jan 13, 2011)

Do any of you own a Sherline CNC lathe?  What is your opinion of it?  Is there anything related to making a pen that it can't do?  I assume you can do threading with the CNC program code, right?  How hard is it to code a CNC lathe?


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## mredburn (Jan 13, 2011)

You can not do cnc threading with the sherline cnc lathe as sold stock by sherline. It can be done but you have to find a way to mount an encoder on the head stock or motor and then find a way to hook the motor up to control the speed in order to maintain the speed of the headstock with the movement of the cross slide to do threading, Johnm just made a call to sherline and asked that very same question.  AS they are produced now you still have to buy the threading gear kit and put the gears and assemblies on the lathe thread by hand and then remove the threading parts to use the lathe in normal operation. 
Mike


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## BRobbins629 (Jan 14, 2011)

glycerine said:


> How hard is it to code a CNC lathe?


Its like pen making - easy to get started, a few years to become proficient. This is a book that I started with...
http://www.cncintro.com/ 

You can also download a trial version of Mach3 which is the control software the majority of CNC operators use. Its fully functional up to 500 lines of code and you can watch the part being machined on the screen. I did this a few months before I actually got my CNC working so by the time I was ready to use it, I could at least get started.

You can also get some CAD programs that will generate the code for you. These range anywhere from freeware to thousands of dollars.

For pen making, I would consider a 4 axis CNC mill before a CNC lathe. The lathe would be good to make high volume replicates of barrels.  The mill can do more intricate designs and engraving.


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## glycerine (Jan 14, 2011)

Is the CNC code language similar to a normal programming language?  I'm a computer programmer, so I work with various programming languages all the time, but have no idea what CNC code looks like.
Thanks for the info.  I'll take a look at the Mach3 trial...


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## glycerine (Jan 14, 2011)

Also, would anyone discourage against going straight to a CNC machine?  Would it be better to get a mill or metal lathe to learn a bit first and then add CNC to it later?  I feel like I'm a pretty fast learner, but I'm not a machinist and I've heard the learning curve is steep...
I guess I can disconnect the stepper motors and operate by hand if I needed to?


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## BRobbins629 (Jan 14, 2011)

glycerine said:


> Is the CNC code language similar to a normal programming language? I'm a computer programmer, so I work with various programming languages all the time, but have no idea what CNC code looks like.
> Thanks for the info. I'll take a look at the Mach3 trial...


Its easier than programming language.  Each line very simply tells the motor or axis how far to move (inches or radial degrees), which way to move (left/right; up/down; and how fast to move.
X1 Y1 F3 for instance says move 1" in X direction, 1 inch in Y at 3 inches per minute.


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## BRobbins629 (Jan 14, 2011)

glycerine said:


> Also, would anyone discourage against going straight to a CNC machine? Would it be better to get a mill or metal lathe to learn a bit first and then add CNC to it later? I feel like I'm a pretty fast learner, but I'm not a machinist and I've heard the learning curve is steep...
> I guess I can disconnect the stepper motors and operate by hand if I needed to?


 I have a non CNC metal lathe but I went straight to CNC for my mill; if you have the budget you won't be sorry.  In any event I think its a small risk.  Take a look at used hobby CNCs on ebay.  They sell for almost as much as new.


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## glycerine (Jan 14, 2011)

Alright, good to know.  Thanks again for the info!


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## lazylathe (Jan 14, 2011)

Have a look here:
http://www.homemodelenginemachinist.com/

A few guys have their Sherline lathes set up for CNC

Andrew


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## lazylathe (Jan 14, 2011)

Also check out this guys amazing Sherline lathe!

http://www.youtube.com/user/tryally#p/u/9/cEcHXuXQr4Y


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## glycerine (Jan 14, 2011)

Thanks for the links.
So, as far as cutting threads, is that more easily done on a 7 x 10 or 7 x 12 with change gears and a lead screw?  What I'd MOSTLY like to do is make some pen parts from stainless steel, brass, etc as well as cut threads.  Once I actually get a mill or lathe though, I know I will try other things as I learn how.


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## mredburn (Jan 14, 2011)

He is using 3 lathes on his threading video. He uses a 4410 cnced sherline (metric) longbed lathe to round the keystock. He takes it to a manual 4410 to cut the 45degree starting bevel and then he puts it on a 4100 cnced lathe to cut the threads. the third lathe has had the original motor replaced with a stepper motor and if you look it has a modified gear assembly mounted from the headstock to the lead screw. This is probably a dedicated lathe for threading. Its interesting that he uses a gear ratio to feed the threading tool He will have to change gears to change tpi.


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## BRobbins629 (Jan 14, 2011)

I would stay away from the 7 X 10 as you will probably need the extra room, but a 7 x12 is a real good size to learn on and is very capable of making pen parts, mandrels, etc. in the materials you describe.  After learning, you will know if and to what you want to upgrade and can easily sell the smaller lathe.  Cutting threads, even multi-start, can be done on these with some practice and guidance from the pros on here.


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## mredburn (Jan 14, 2011)

I agree with Bruce, I have the Sherline lathes but they have a couple serious shortcomings.
1- The basic lathes do not come with threading capabilities or a compound cross slide to cut angles. 
2- Those accessories are expensive. Both run about $120. each new. Plus you have put the threading kit on thread your piece and then take the threading kit back off to use the lathe again.

For simple pen making operations the 7x12 or larger lathes that come with the compound slide and theading abilities are quite adequate for most if not all that you want to do. Are there better lathes sure. But these small lathes may be all you need for a long time. 

Mike


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## glycerine (Jan 14, 2011)

Yeah, I had looked at the 7 x 12's but thought I may need something that's CNC'd to do the shaping.  Would it be fairly easy to make a finial, or "nib" end manually on a metal lathe?  I guess the better question is, is it easy to cut curves?


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## workinforwood (Jan 14, 2011)

All the basic funtions to make a pen are on a metal lathe.  Once you have one and use it awhile, the wood lathe kinda seems silly to keep around. The metal lathe will do every function the wood lathe does and then many many more.  You can manually cut curves, but it's hard to get them really flowing evenly because you are spinning nobs like rubbing your belly and your head at the same time. But..we all know where there is a will, there is a way!  Mostly likely there's ways to jig up the machine to do a curve, but there is also just the simple chisel method too..metal can often turn with woodturning tools, so you make a nib and want some round dip in it, mount a post and get out your chisel, or just a round file, whatever.  I can make a threaded nib with 15 degree taper for a cigar pen in 10 minutes.


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## BRobbins629 (Jan 14, 2011)

glycerine said:


> Yeah, I had looked at the 7 x 12's but thought I may need something that's CNC'd to do the shaping.  Would it be fairly easy to make a finial, or "nib" end manually on a metal lathe?  I guess the better question is, is it easy to cut curves?


Yes its easy to make a finial, nib, section or curved parts on the metal lathe without CNC.  Its done all the time.  I know of several pen designers who have CNC lathes for production work but do the initial design prototyping on a manual metal lathe.


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## workinforwood (Jan 15, 2011)

If you take a vertical mill and lay it on it's side, you now have a horizontal mill...which is practically the same thing as a lathe.  You get a collet chuck on that lathe and you can buy mill cutters and you can easily adapt the cross slide to hole a vise and now you can mill flutes and all kinds a stuff manually on your lathe.


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## glycerine (Jan 15, 2011)

Thanks, you guys have been vey helpful answering all of my questions.  I know I will need to buy some cutting bits, and will probably WANT a quick change post.  And a collet chuck and vise for the cross slide has been mentioned.  What other accessories would you recommend that would be helpful or necessary in making pen parts?  I'm guessing that I will spend at least $500 extra on top of the cost of the lathe.  Is that a reasonable estimate?


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## mredburn (Jan 15, 2011)

And yet another dark abyss opens beneath your wallet, sucking your hard earned dollars into another dimension. A place so deep, dark, and vast its known only as " THe Turning Zone"


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## glycerine (Jan 15, 2011)

mredburn said:


> And yet another dark abyss opens beneath your wallet, sucking your hard earned dollars into another dimension. A place so deep, dark, and vast its known only as " THe Turning Zone"


 
Yep!  I'm not buying anything right now though.  I have a birthday coming up in a few months, so I'm preparing my list!
I THINK my best option is to get a 7 x 12 (or even a 9 x 19) for now.  And add CNC later.  I've looked at the mills, but I think I could do more of what I want to do with a lathe instead of a mill.  I would get a combo, but I've hard those are not very good?  Do you guys agree?  If I want a lathe, buy a lathe.  If I want a mill, buy a mill?


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## workinforwood (Jan 15, 2011)

I spent $1500 on my lathe, probably have $3000 in accessories and still buying them. A combo machine is a waste of money, the so called mill does not move, it just stays where it is which means you can use the cross slide with a vise to mill parts but you are very limited in movement because the headstock of the lathe gets in the way and you can't expect to mount something in the lathe and mill it with the mill because you can't reposition the mill to correspond with the part in the lathe.  Basically, the mill just sits there and takes up space, gets in your way.  If you buy the biggest lathe you can afford, it's going to be the best thing you ever did. Don't worry about tooling, because you can just buy one little thing at a time, even if the lathe has to sit there for several months because you have no money for tooling it's worth it.  After you use the lathe a while, you may discover you never need a mill, because like I said, a lathe is also a mill, even though it's a little bit more limited than a mill due to the fact that the a mill has a large table, but to make pens, they are small enough that you can mill anything with your lathe. You need collets, a collet chuck or collet drawbar closer system. You can use collets to hold rods and make pens of course, and for drilling, but also, you can get a collet fixture that you can mount on your cross slide which would also have indexing and those can be found real cheap, so now you can use your collets not just to spin, but to adapt your lathe into a mill.

There's a billion types of collet fixtures, and this is just the first one that popped up in a search engine. http://www.auto-met.com/subtool/stcat/st_pg7a.html
typically, they would have a larger base you can mount on your slide. You can just see the possibilities with one of these..I've seen ones as cheap as $30. That is how you use your collets to convert a lathe to a mill. Of course, if you have a regular vertical mill, you can also use a collet fixture to hold parts and do index cuts or holes.


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## BRobbins629 (Jan 15, 2011)

glycerine said:


> Thanks, you guys have been vey helpful answering all of my questions.  I know I will need to buy some cutting bits, and will probably WANT a quick change post.  And a collet chuck and vise for the cross slide has been mentioned.  What other accessories would you recommend that would be helpful or necessary in making pen parts?  I'm guessing that I will spend at least $500 extra on top of the cost of the lathe.  Is that a reasonable estimate?


Here would be my list for starters:
Quick Change tool post
Collet chuick with 18 collets
Drill chuck for tailstock
Die holder for tailstock or drill chuck
Set of taps and dies
Bench grinder - you can but tools, but for about 1.00 each you can get some tool blanks to grind - comes in very handy
Couple of feet of brass stock for special mandrels

That will keep you going for quite a while.


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## glycerine (Jan 15, 2011)

I do have a bench grinder, and an MT2 jacobs chuck for my wood lathe.  Might be a bit big though for a metal lathe though...


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