# Considering CNC - What's Your Opinion



## TomS (Jul 17, 2013)

I've been machining for many years both as a profession and hobby.  My understanding of manual machining is high but I know little about CNC other than a software program tells the electric motors which direction and speed to turn.  That's an over-simplification of what I think I know but that's why I want to learn more.  So I've been thinking about getting into CNC machining (milling mostly) but don't know enough yet to pull the trigger.  My budget is limited so buying a new machine with the size capabilities I'm looking for probably won't work out.  I have an 2 HP Enco mill/drill that's a couple of years old but because I'm electrically and electronically "challenged" going down the retrofit road is not a good idea, at least for me.  I'd like to find a "package" that I don't have to piece together with software that is relatively simple to learn.  Used machines are a consideration but I don't want to buy something that's worn out or inherit someone else's problems.     

I found an Ebay listing for Model Shop CNC that looks interesting.  Other than losing some Z axis capacity what do you think about going this route?  It appears to be complete, except for the computer and monitor.  Anything else I'm missing or should consider.  

Sorry for the jibber-jabber just trying to give everyone a feel for where I'm coming from.

Thanks in advance for your opinions.

Tom S.

http://www.ebay.com/itm/CNC-XY-Mill...371?pt=US_Heavy_Equipment&hash=item19de2fbad3


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## Ray C (Jul 17, 2013)

Welcome Tom to the summer semester of CNC for newbys...  I'm in the same boat.  Please feel free to jump in on this thread: http://www.hobby-machinist.com/show...Lining-up-the-ducks-Asking-software-questions


Ray


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## DMS (Jul 17, 2013)

Seems like with that package you only get a 2 axis system (you will be cranking the Z axis yourself). I did this on my mill before I completed the quill feed, but it gets a little old, and you will not be able to do 3d contours (maybe that's not a feature you need). 

You may want to check out the "Basic CNC" thread in this forum. We were able to condense a lot of info there. 

Whatever your budget is, make sure you consider the software side in it too. What size machine are you looking for?


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## TomS (Jul 17, 2013)

DMS said:


> Seems like with that package you only get a 2 axis system (you will be cranking the Z axis yourself). I did this on my mill before I completed the quill feed, but it gets a little old, and you will not be able to do 3d contours (maybe that's not a feature you need).
> 
> You may want to check out the "Basic CNC" thread in this forum. We were able to condense a lot of info there.
> 
> Whatever your budget is, make sure you consider the software side in it too. What size machine are you looking for?



First let me say thanks for your comments.  This particular package does come with a Z axis motor but not a mounting bracket or coupling.  I can handle making the bracket.  I can only assume at this point that it's a simple matter to activate the motor.

I'm looking for an X axis travel of about 10" to 14" and X axis travel of 6" to 8".  Wish this package had more X travel but at 10.5" it should handle most of what I anticipate needing.

I've heard and read of Bobcad and Mach 3 software.  Don't know the intricacies of using them but my understanding is they are good programs.

- - - Updated - - -



Ray C said:


> Welcome Tom to the summer semester of CNC for newbys...  I'm in the same boat.  Please feel free to jump in on this thread: http://www.hobby-machinist.com/show...Lining-up-the-ducks-Asking-software-questions
> 
> 
> Ray



Thanks for the info and invite.  I'll check out the link tonight.  Yard duty calls.


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## DMS (Jul 17, 2013)

Sorry, I missed the bit about the Z axis motor.

Mach3 and BobCAD/CAM fill 2 requirements you need to really use a CNC machine. Mach3 is a "controller"; you feed the controller the GCODE program that you either wrote by hand, or that your CAM package generated, and it tells your machine to do based on that. BobCAD/CAM lets you draw your parts, and then generate code to feed into the controller. Mach3 is very common (the most common PC based controller). BobCAD/CAM seems to be a love it or hate it sort of thing. For both of these packages, I believe you can download a trial version to see if you like them.


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## TomS (Jul 17, 2013)

DMS said:


> Sorry, I missed the bit about the Z axis motor.
> 
> Mach3 and BobCAD/CAM fill 2 requirements you need to really use a CNC machine. Mach3 is a "controller"; you feed the controller the GCODE program that you either wrote by hand, or that your CAM package generated, and it tells your machine to do based on that. BobCAD/CAM lets you draw your parts, and then generate code to feed into the controller. Mach3 is very common (the most common PC based controller). BobCAD/CAM seems to be a love it or hate it sort of thing. For both of these packages, I believe you can download a trial version to see if you like them.



I'll check out the trial versions and see what questions come up.  Reading elsewhere I understand that a translator program is needed to transmit data from the CAD program to the controller program so G code can be generated.  Any suggestions and what can I expect to pay?


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## DMS (Jul 17, 2013)

The "Translator" program you describe is called a CAM (Computer Aided Manufacturing) package. I think BobCAD may have that integrated into it, but it may be an option (I don't use BobCAD personally).

Prices range widely, and I have seen prices from a couple hundred, to 10s of thousands of dollars for the high end CAM packages. I currently use AlibreCAD and AlibreCAM. Total cost was under 3k, but I didn't get the "basic" versions. 

One low cost package I have seen mentioned is "CamBam", but I didn't spend much time trying it out personally. I'm sure others will pipe up with there experience as the evening progresses.


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## geotek (Jul 17, 2013)

First you should define what you plan to do with the CNC.  This will determine the type of machine you need.  With access to a machine shop and your knowledge you could build your own machine from scratch to fit your needs.  I built a 27x48x5" gantry machine capable of high precision work on wood, plastics, and aluminum.  The machine was built for less than the eBay machine is selling for.  BTW, if you are doing much engraving or 3D carving, you will find the Z axis is by far the busiest axis.  So make sure you pay close attention to this axis.


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## Hawkeye (Jul 18, 2013)

Tom, setting up the electrical bits on a CNC conversion isn't all that difficult. Quite a few of us on this forum have ordered stepper motors, power supplies, boards and ballscrews on-line. Control hardware is mostly plug-and-play, with some settings to enter into the controller software. You have the skills to machine ballscrews and make the brackets. 

You'll find lots of help in this group. Budget can be a big issue that's hard to overcome in a ready-to-use machine, unless you happen to find something advertised that isn't 400 pounds of nightmare. You could even think of that as a kit - all of the parts are there, just have to be put together properly.

As much as I like the hands-on feel of machining, there's something about watching your CNC mill cutting out something you designed and told it to make, with the occasional "Oh nooo!" moment thrown in.


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## Rbeckett (Jul 18, 2013)

I would definitely get in touch with Steve (Jumps4) and talk to him about what you want to add CNC to.  He has done his own and a couple of others with other members already so he has a pretty good system figured out and it seems to be working glitch free pretty much straight out of the box.  I know steve did his RF clone and so did Mac (7HC) as well as another fellow he is also helping build an enclosure for too.  Matt at Precision Mathews also has some CNC kits he installs on his machines that should simplify the install quite nicelt also.  There is nothing to be scared of doing it for yourself.  The learning curve is steep but gentle and tha hardware is very forgiving and quite robust so you can install those parts easily in an afternoon.  I believe if you have been a machinist for very long you definitely have the skill set you would beed to install it and make it work very easily.  So I have faith in ya and I am sure you can do it with just a little bit of help if you get stuck along the way.  So don't give up before you even get started because it is actually easier than you think to add all of the parts, and building G-code is very logical so you will learn that very fast too.....

Bob


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## TomS (Jul 18, 2013)

Rbeckett said:


> I would definitely get in touch with Steve (Jumps4) and talk to him about what you want to add CNC to.  He has done his own and a couple of others with other members already so he has a pretty good system figured out and it seems to be working glitch free pretty much straight out of the box.  I know steve did his RF clone and so did Mac (7HC) as well as another fellow he is also helping build an enclosure for too.  Matt at Precision Mathews also has some CNC kits he installs on his machines that should simplify the install quite nicelt also.  There is nothing to be scared of doing it for yourself.  The learning curve is steep but gentle and tha hardware is very forgiving and quite robust so you can install those parts easily in an afternoon.  I believe if you have been a machinist for very long you definitely have the skill set you would beed to install it and make it work very easily.  So I have faith in ya and I am sure you can do it with just a little bit of help if you get stuck along the way.  So don't give up before you even get started because it is actually easier than you think to add all of the parts, and building G-code is very logical so you will learn that very fast too.....
> 
> Bob



Thanks to everyone for your input.  I've got some work to do so I can better understand the intricacies of CNC before making a decision.  I'll let you know how it turns out.


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## Mid Day Machining (Aug 6, 2013)

I would stay away from 2 axis machines. Far, far away. I bought a Tormach PCNC 1100 2 years ago and haven't regretted it for an instant,

I owned a real CNC shop for about 7 years. I had a FADAL 3016, a Haas TM1 with 5C rotary axis, and a heart attack.

I retired after the heart attack, but I just couldn't keep my hand out of the machine shop. 

I had a couple of part time jobs, but I got laid off when the economy took a dump.

After about 3 years with nothing to do, I decided, screw it and I bought my Tormach. It has 18 inches of X axis travel, 9 1/2 inches of Y axis and 16 1/4 inches of Z. The problem with a knee mill with a retrofit control is most of them have 3.5 to 5 inches of Z travel, and I can almost guarantee you thet the firse job tou get will have a hole that is .500 deeper than the travel on your machine.

If you can do it, then by all means, do it. You won't regret it.

Steve


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## TomS (Aug 6, 2013)

Steve Seebold said:


> I would stay away from 2 axis machines. Far, far away. I bought a Tormach PCNC 1100 2 years ago and haven't regretted it for an instant,
> 
> I owned a real CNC shop for about 7 years. I had a FADAL 3016, a Haas TM1 with 5C rotary axis, and a heart attack.
> 
> ...



Thanks for the support.  I downloaded a trial version of BobCad V25 and Mach 3.  I've struggled a bit with the CAD program but am learning every time I play with it.  Tried simulating a simple milling part but keep getting the error message "operation not defined".  Working on correcting this problem then will move on something more complex.

While I'd like to have a machine like a Tormach, my budget, and my financial advisor (aka wife), won't allow it.  After reading input from others on this forum and other websites I am considering piecing together a package and converting my mill drill.  I'll see where all this leads me.

Thanks again.


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## coherent (Aug 8, 2013)

Sorry if I ramble and get off on a tangent that you're not interested in. I'm not a machinist by trade and still learning. I have always wanted a mill and when I finally got a small benchtop model, I realized how little I knew about the machining world. My thoughts after playing with the mill for a few weeks was "why in the world would someone want to sit here turning these handles and making all these measurements and adjustments if you could just hook up some electronics and motors and let it do by itself"? Well obviously knowing how CNC works doesn't mean I knew all the tricks of milling and machining. 
I knew something about CNC from other hobby machines I had built but I knew little about machining with a mill.  You have a big advantage, you know what processes need to be done. Making the computer/motors end of the CNC do it for you is much easier than you think. A solid background and understanding of manual machining would help tremendously for anyone getting into CNC machining. Like everything else, in the hobby and retrofit CNC world you can spend as much as you want. I know a lot of folks buy a small mill (grizzly, HF, LMS etc) and either purchase or build/assemble the CNC components or kits with great results. If I could do it (and I did), anyone can and I sincerely mean that. One of the most daunting tasks initally if you're not already familiar with CAD and CAM software is learning the software. Someone can show/teach you in a few hours what would take weeks by reading and trying to "figure it out". Find someone in your town that's willing to spend a little time to help you in person. 
I bought a High Torque mini mill from the little machine shop and converted it to CNC. Cost directed my decision against a kit of any kind. I'm very happy with the results and avoided spending at least twice as much a retrofit kit/parts would have. In some cases what I used was as good or better than available kits offered. If you don't want to use your current drill/mill get a machine big enough machine to suit your expected needs, and with your manual machine knowledge, you should have no trouble building the motor mounts, bearing mounts, machining lead screws ends (if you have a lathe) etc for a machine. A 4 axis gecko controller (like the G540) is a great controller and fairly inexpensive. On the lower cost end,  ball screws can be found on ebay from China that are fairly accurate and work well for many folks. Then of course it goes up from there. As you're probably already aware there are a few folks who offer partial kits to complete retrofits for small/mid size mills. I guess it's all a matter of how much money you want to spend and how much work building parts you want to do. For me I enjoyed making all the parts myself, it was part of the fun (and remember I had no prior mill experience). I know you said you'd rather not retrofit the machine you have, but I think you'll find doing so would be the most cost effective and rewarding route to take. I can guarantee you that (even if you make the parts yourself) what seems extremely confusing or out of your abilities now regarding CNC will all become clear and look MUCH less complex in just a short time. Especially the machine and controller aspects (even the controller software like Mach). The CAD and CAM software takes some folks a little more time to become proficient, but that applies if you have a complete CNC mill ready to run or assemble it yourself, and troubleshooting accuracy or other issues (and they will arise without a doubt) will be much easier if you know how all the CNC components are assembled and what they do. Just Do it! The complete retrofit kits that include the controller, motors, screws and software etc., would be the 2nd best route in my opinion. It'll cost a lot more, but will simplify things somewhat, but not as much as you may think.  Sorry so long winded and best of luck no matter which route you take. If you enjoy machining, you'll have a blast with CNC machining!


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## TomS (Aug 9, 2013)

coherent said:


> Sorry if I ramble and get off on a tangent that you're not interested in. I'm not a machinist by trade and still learning. I have always wanted a mill and when I finally got a small benchtop model, I realized how little I knew about the machining world. My thoughts after playing with the mill for a few weeks was "why in the world would someone want to sit here turning these handles and making all these measurements and adjustments if you could just hook up some electronics and motors and let it do by itself"? Well obviously knowing how CNC works doesn't mean I knew all the tricks of milling and machining.
> I knew something about CNC from other hobby machines I had built but I knew little about machining with a mill.  You have a big advantage, you know what processes need to be done. Making the computer/motors end of the CNC do it for you is much easier than you think. A solid background and understanding of manual machining would help tremendously for anyone getting into CNC machining. Like everything else, in the hobby and retrofit CNC world you can spend as much as you want. I know a lot of folks buy a small mill (grizzly, HF, LMS etc) and either purchase or build/assemble the CNC components or kits with great results. If I could do it (and I did), anyone can and I sincerely mean that. One of the most daunting tasks initally if you're not already familiar with CAD and CAM software is learning the software. Someone can show/teach you in a few hours what would take weeks by reading and trying to "figure it out". Find someone in your town that's willing to spend a little time to help you in person.
> I bought a High Torque mini mill from the little machine shop and converted it to CNC. Cost directed my decision against a kit of any kind. I'm very happy with the results and avoided spending at least twice as much a retrofit kit/parts would have. In some cases what I used was as good or better than available kits offered. If you don't want to use your current drill/mill get a machine big enough machine to suit your expected needs, and with your manual machine knowledge, you should have no trouble building the motor mounts, bearing mounts, machining lead screws ends (if you have a lathe) etc for a machine. A 4 axis gecko controller (like the G540) is a great controller and fairly inexpensive. On the lower cost end,  ball screws can be found on ebay from China that are fairly accurate and work well for many folks. Then of course it goes up from there. As you're probably already aware there are a few folks who offer partial kits to complete retrofits for small/mid size mills. I guess it's all a matter of how much money you want to spend and how much work building parts you want to do. For me I enjoyed making all the parts myself, it was part of the fun (and remember I had no prior mill experience). I know you said you'd rather not retrofit the machine you have, but I think you'll find doing so would be the most cost effective and rewarding route to take. I can guarantee you that (even if you make the parts yourself) what seems extremely confusing or out of your abilities now regarding CNC will all become clear and look MUCH less complex in just a short time. Especially the machine and controller aspects (even the controller software like Mach). The CAD and CAM software takes some folks a little more time to become proficient, but that applies if you have a complete CNC mill ready to run or assemble it yourself, and troubleshooting accuracy or other issues (and they will arise without a doubt) will be much easier if you know how all the CNC components are assembled and what they do. Just Do it! The complete retrofit kits that include the controller, motors, screws and software etc., would be the 2nd best route in my opinion. It'll cost a lot more, but will simplify things somewhat, but not as much as you may think.  Sorry so long winded and best of luck no matter which route you take. If you enjoy machining, you'll have a blast with CNC machining!




Your response and those of others that took the timer to offer their advice is why I joined this forum.  I've received nothing but positive feedback and support.

You are absolutely spot on about learning the CAD/CAM side of the equation.  I'm very familiar with drawing and reading 2D blueprints but 3D has been more of a challenge than I anticipated.  CAM has also been a steep learning curve.  Haven't given up and learning every time I open the program.  

I've been doing research on off-the-shelf mills, retrofit kits and individual components, and of course the X/Y cross slide set-up I mentioned in my original post.  And I agree with you that the individual component route is the most cost effective way to go.  Just don't have the confidence level yet to make the decision.

Thanks


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## medlin6 (Sep 3, 2013)

I have been using BobCad for 10 years and I love it.
This program let's you design program and post for your controller.
You don't need any other program


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## Ray C (Sep 3, 2013)

I totally understand the desire to "build your own" and realize there is no Right or Wrong answer on this matter (so please do not interpret this as being argumentative.  -truly not meant that way).  I've spent more time than I want to admit thinking about "Build or Buy", I'm falling on the "Buy" side of the fence this time.   In my professional career, I've designed/built so many products, I couldn't begin to remember them all.  I do know that each and every one had it's share of tough spots and rough going -and this is one time in my life where I'm looking for something that is as "turnkey" as possible.  I roughly estimated it will take (conservatively) 2-3 weeks to research and select the components, 2-3 weeks to do the installation and another 2-3 weeks to get it all working.  This is extremely short duration for the things I do professionally but, the difference is that I have to effectively work another 8 hours per day to keep up with my hobby... The plan is that with the hundreds of hours I don't spend researching components, assembling and debugging, I'll spend instead on learning CAM and controller software.

I've got the choice of machine in mind.  I've got a fairly good handle on 3D CAD -and starting fairly soon, I'll refer back to this thread and start looking at all the CAM suggestions.  I'm hoping to have the machine by the end of this year and when it arrives, I'm hoping I'll be making the first parts in a week or so.  -And trust me, it's really hard for me not to daydream about his all day long...


Ray





TomS said:


> Your response and those of others that took the timer to offer their advice is why I joined this forum.  I've received nothing but positive feedback and support.
> 
> You are absolutely spot on about learning the CAD/CAM side of the equation.  I'm very familiar with drawing and reading 2D blueprints but 3D has been more of a challenge than I anticipated.  CAM has also been a steep learning curve.  Haven't given up and learning every time I open the program.
> 
> ...


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