# CNC advice



## Russianwolf (Mar 13, 2012)

okay, I'm heading in a new direction at the request of a friend. If I can make the business plan work, I could be looking at a nice steady side job. The part that is eluding me is I need a cnc 4 axis engraving mill. 

I can make the prototype parts and hire out the cnc work locally (current plan), but I obviously stand to make more if I can keep it in house. 

I'd like to find a nice American made unit, but I don't know if the Tiag or Sherline units have the detail work that I'll be looking for and they run $4k+. There are some chinese units that look promising for less than $2k, but I can't find any user reviews so am hesitant. 

Any other options or advice? Feel free. And yeah, I know I'll have to learn to program the thing and all, but it will be much quicker than doing them by hand and then needing the engraving done anyway.


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## mredburn (Mar 13, 2012)

Taig all the way, Deepgroove1 Home Page  $1700.00 plus the  sherline rotary axis drive. 
You can find them on ebay for $1400 with the rotary 4th axis included.


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## mredburn (Mar 13, 2012)

You will need software for the computor to run the cnc mill. You will need software to design the parts. You will need software to plan the tool paths. There are many different choices depending on the size of your wallet. Bruce (Brrobbins) will be along and can tell you how he does it. I didnt have any experiance writeing Gcode and I need to produce parts not learn to program from the begining. I use Rhino, & RhinoCam with 4 axis. They are two different companies. Visaual MIll is another option and the same company that writes RhinoCam for Rhino. There are as many answers as there are people that use cnc. you will have to sort through some of it to find whats best for you.

I also use Mach 3 for the controller software for the mill computor.


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## 691175002 (Mar 13, 2012)

It depends a lot of the size of work and what materials you will be machining.

If this is your first machine I would recommend getting something reputable.  A lot of deals are good, but most of the time they have quirks that you need to work around.


Also remember that tooling is very expensive.  Doing accurate work is also very expensive.  Measuring equipment, workholding, cutters and all the other stuff you end up needing adds up fast.

Software is also very expensive.


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## mredburn (Mar 13, 2012)

Here are pictures of waxes I cut to cast, made on my taig. 










the cast piece





The minitech is a better mill than the taig but you have to add another "0" to the $1700 of the taig.  I used the taig to build a larger mill. I cut wood, plastic, wax, and alumunum on it. I can but choose not to cut steel on it. I use .003 tapered ballnose cutters to cut wax. I do have problems with details under .002 from back lash in the mill. It does not use ball screws but 20tpi threaded lead screws.


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## btboone (Mar 13, 2012)

I have a MicroKinetics 4th axis tabletop mill based on a Sherline.  It works great, and I use it just about every day.


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## BRobbins629 (Mar 13, 2012)

Agree with Mike on the Taig as long as the footprint is big enough for what you want.  You can do a lot with a small footprint, but make sure.  Also if its just for engraving, are you sure you want a CNC and not a laser?  I have no experience with the laser, but here are some other considerations.

The small bits you will likely use for engraving and pen work like high speeds.  Make sure the spindle on the one you get can run continuously at the speed recommended for your bits.  I normally run my spindle at about 15,000 rpm.  Some are designed for larger bits, more torque and run slower.

There are several types of software and you will really have to demo them (they all have demo versions) to find one you are comfortable with.

Most CNC machines run with Mach3.  This is the program that interprets the Gcode whether you write it or one of the design programs spits it out. License is $175.  You can download the program and use it without a license for up to 500 lines of code for free.  I always recommend doing this and run in simulate mode long before you get your machine.  It take a few weeks or more to get used to and once you get your machine you will have a head start.

As for writing GCode, you can do it yourself or use one of many CAD programs available for low cost up to many $1000s.  I enjoy writing code, but if I ever do engraving I would use one of the CAD programs.  I started with a program called DeskCNC which is about $200 or less.  It is very capable for engraving and inlaying and even some 3D.   Many use Rhino.  Another one for 3D work is Vetric Aspire but that is several $1000.  Also check out CNC4free.org


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## Russianwolf (Mar 13, 2012)

Thanks guys, time for more reading. 

This will be for jewelry type work, though I may try some pen stuff during free time. I need the machine to be able to carve in soft metals and wax. Sterling and dare I say gold will be the goal, though stainless isn't off the table. Then it needs to be able to do detail work similar to guilloche (can't afford 15-40k for an engine). 

All this came up from a chance meeting with the owner of the jewelry store my mother used to work for.


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## mredburn (Mar 13, 2012)

All the matereials you mention are doable. You just need the right size bits, spindle speed, and cuts programed.


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## mredburn (Mar 14, 2012)

If you decide on the Taig you might also want to check out *Soigeneris.com*
He also sells the same taig machines and builds the controllers. I have both, one of his controllers  and One of Deep grooves they both use the gecko 540. THE price difference is $400.00 more for one from Jeff. Its worth it if your going to use your mill to work with and not as a hobby machine. Better parts, better box design, better support after the sale. As in almost none from Deepgroove. 

I would recomend you get the er16 spindle if you do decide to use Either Sherline or taig.  Thier top end spindle speed is 10,000rpms.


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## btboone (Mar 14, 2012)

I use a Foredom as my spindle to get 18,000 rpms.


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## Russianwolf (Mar 14, 2012)

btboone said:


> I use a Foredom as my spindle to get 18,000 rpms.



Yeah, that's what the chinese units are built around. I assume if the mill motor isn't up to my needs, I can swap it out for a Foredom. The CNC is just controlling the the movement of the axis, not the speed of the spindle like it does in a lathe, right?


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## BRobbins629 (Mar 14, 2012)

I too use a Foredom, but just bought a used NSK off of ebay which I am in the process of hooking up. Came from the bankrupt Solundra plant, so thanks to all of the taxpayers who subsidized this for me.. If you do go the Foredom route which would the right spindle for what you describe, why not start there? You should get the heavier continuous duty handpiece with collet chuck and the 1/3HP motor. Don't undersize. For carving wax and other materials, many pieces will be on the mill for several hours. I've run pieces as long as 9 hours.

The spindle can be controlled by the CNC or independantly.  Depends on how you hook it up. Mine is independant.


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## Russianwolf (Mar 14, 2012)

BRobbins629 said:


> I too use a Foredom, but just bought a used NSK off of ebay which I am in the process of hooking up. Came from the bankrupt Solundra plant, so thanks to all of the taxpayers who subsidized this for me.. If you do go the Foredom route which would the right spindle for what you describe, why not start there? You should get the heavier continuous duty handpiece with collet chuck and the 1/3HP motor. Don't undersize. For carving wax and other materials, many pieces will be on the mill for several hours. I've run pieces as long as 9 hours.
> 
> The spindle can be controlled by the CNC or independantly.  Depends on how you hook it up. Mine is independant.



You mean they sell the units with a foredom already installed, or buy both and set up before getting it running? Making sure I understand the options.


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## Timebandit (Mar 14, 2012)

Russianwolf said:


> BRobbins629 said:
> 
> 
> > I too use a Foredom, but just bought a used NSK off of ebay which I am in the process of hooking up. Came from the bankrupt Solundra plant, so thanks to all of the taxpayers who subsidized this for me.. If you do go the Foredom route which would the right spindle for what you describe, why not start there? You should get the heavier continuous duty handpiece with collet chuck and the 1/3HP motor. Don't undersize. For carving wax and other materials, many pieces will be on the mill for several hours. I've run pieces as long as 9 hours.
> ...



I believe this is what he means https://www.google.com/search?q=foredom+handpeice&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a#q=foredom+handpiece&hl=en&client=firefox-a&hs=IFW&rls=org.mozilla:en-USfficial&prmd=imvns&source=univ&tbm=shop&tbo=u&sa=X&psj=1&ei=BLRgT-6bHo7hsQKe7uWWCA&ved=0CIABEK0E&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=5130e27aaf419cd4&biw=1280&bih=697 
 
Or this, the full unit https://www.google.com/search?q=for....,cf.osb&fp=5130e27aaf419cd4&biw=1280&bih=697


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## BRobbins629 (Mar 14, 2012)

Russianwolf said:


> You mean they sell the units with a foredom already installed, or buy both and set up before getting it running? Making sure I understand the options.


 
If you can, I would get one with the Foredom installed, else it may be a later upgrade.  Try to contact Nick Carter - he has a great web site with tons of info and also sells modified Taig equipment.  He may be able to provide what you need.  

You can also save some money with a DIY kit.  Have a look at IMService we are THE source for low cost Cad-Cam and Desktop CNC Mills, lathes, and Routers


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## btboone (Mar 14, 2012)

Yes, I have the CNC that just turns the motor on and off and there's a speed control on my Foredom base.


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