Cnc building ?s

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Naiveambition

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I'm having somewhat of a dilemma and, " I'm not totally sure but the problem may be I don't know what the hell I'm doin" ... :D:D

I want to learn cnc. Which is the goal. I have a standard zx 45 mill that I want to convert. If I install the required motors combined with zero knowledge of how to run one, will it destroy its self? Like blowing drives , breaking parts etc...
I have read numerous threads on installs so I'm relatively confident I can pull it off, especially with the help here.

My second thought is to build a small cnc router to learn with, so when it breaks it is cheap to replace. And can use it to build the parts for the big mill. Or am I over thinking what can happen.
With money scarce I would like to start with the path of least resistance :D:D meaning up and running.

If I go with a router I will have to buy the mills also so this ups the cost. Will I be better of just doing the mill, and hang on for the ride?

What would you do?
 
With limit switches on all three axes the movements of the tools are constrained. So most accidents involve running the tool into the work or fixture. When this happens you either break the tool or stall the motor. My mill's head can rotate in the XZ plane so a crash can also misalign the head requiring re-tramming.

It doesn't make sense to build/buy a machine without knowledge of CAD and CAM, so educating yourself on these is a prerequisite to actually being able to use it.
 
The type of mill conversion you are describing has been done countless times and the work is well documented on many forums so if you have mechanical and electrical talents it could be accomplished. That's not to say that it's an easy task, not by a long shot. So lets say you get the mill converted and get everything hooked up and ready to go, now comes the part about learning G codes or even greater still CAD modeling.
I guess what I'm saying is there's a big plunge to go from good sound machining knowledge to CNC.
I would ask myself, "what will I do with it once I have it ready?" This hobby is so vast and the amount of things that can be made with basic machine tools could keep the average builder busy for a good part of his life so that's the reason for the question.
gbritnell
 
Naiveambition,

How much do you want to spend on this project?

Is your goal to build a cnc to learn about cnc or to build a cnc to make parts for some projects you have in mind?

Where are you located?

I am starting to become interested in the cnc world myself, but I have made enough things since I started machining to know that sometimes it is more cost-effective to spend more in the beginning to avoid trouble and frustration later.

I have been considering maybe a turnkey Sherline cnc mill to sort myself through the learning curve of actual operation: This is mainly because my shop is outside and it's getting hard to face work sessions in the cold winter and hot summer and because I have added too many responsibilities in my life to spend lots of uninterrupted hours working on intricate projects. (At least for now, anyway.)

One thing I notice about the various build threads and getting-started articles I have read is that "simple" homemade cnc machines often become much more involved than the concepts that start them. I myself can see me spending much more time and money that way than I would want to at the beginning, so I am holding back until I am sure what path I want to take.
 
Aside from the mechanics of the mill (motors, mounts, limit switches) you have associated electronics and then control software.

Nothing wrong with a turnkey Sherline mill as long as the parts you want to make fit the work envelope.
 
Having done this for over 30 years now I've seen a lot of "CNC operators" come and go. (I have worked in job shops ) I would recommend you learn to make parts manually first. Just my .02 .
 
It doesn't make sense to build/buy a machine without knowledge of CAD and CAM, so educating yourself on these is a prerequisite to actually being able to use it.

As a person who has converted a zx-45 type mill (actually an MD-001 which is the large version, aka Industrial Hobbies / Charter Oak) I can fully recommend learning a CAD and CAM package as a prerequisite.

Having the mill is 1 thing. Running it manually (jog wheel) or quasi programmed (MDI commands) is the next step (and helpfull for learning G-code) but actually leveraging the mills capabilities of cutting out the shape you want in minimum time is where the software comes into play. Now is a great time for this as there recently became available FREE CAD and CAM package that I am still learning but appears to have great potential - Autodesk Fusion 360 (free for hobby and or students etc). I need to spend more time with it but seems like it has all that the hobbyist needs as far as CAD and CAM.

Other advise for home CNC users / builders: skip the carbide end mills, it is much cheaper to replace a HSS tool than a carbide one when you are learning and carbide really only shines when you are pushing it, which most hobbyists don't need to do. There is also the HP factor, many home mills can't spin fast enough or produce enough HP to properly use carbide.

As far as the machine goes - converted properly you will not likely "break" it, just bang it out of tram or break your tools / workpiece / vice and/or dirty your shorts as you will be there when it goes bang!

My 2 cents
Mike
 
Having been a CNC operator, I think a little handwork is a good idea just to get the feel and sound of what is and isn't a sharp tool, and proper federate. Other than that, I would say really understanding how to read a mechanical drawing is invaluable. I've known a lot of CNC operators who were button pushers, and some that understood what was going on after the button is pushed.
 
If you are interested in learning CNC Motion Control, buy an Arduino and a trio of Stepper Motors, make up a little 3 Axis Frame, (just Threaded Rod and Shafting), and play. You will learn a hell of a lot in a short time without damaging yourself or Equipment.
 
I'm having somewhat of a dilemma and, " I'm not totally sure but the problem may be I don't know what the hell I'm doin" ... :D:D



I want to learn cnc. Which is the goal. I have a standard zx 45 mill that I want to convert. If I install the required motors combined with zero knowledge of how to run one, will it destroy its self? Like blowing drives , breaking parts etc...

I have read numerous threads on installs so I'm relatively confident I can pull it off, especially with the help here.
Sure it is possible to break things, blow drivers and etc! Will that happen, I can't say because I don't know what sort of CNC technician you are.
My second thought is to build a small cnc router to learn with, so when it breaks it is cheap to replace. And can use it to build the parts for the big mill. Or am I over thinking what can happen.
Routers are interesting machines in that there is a wide array of possible implementations, some cheap some not so cheap. The question is how in depth do you want the learn CNC technology, because honestly your money might be better spent in a tech school program. Other questions you need to consider is how good do you learn on your own. Also how is your electronics background?

What I'm saying is that there is no right answer. For some people having a machine to tinker with is the best way learn some of the basics of CNC operation. The machine however will do nothing for you CAD/CAM wise.
With money scarce I would like to start with the path of least resistance :D:D meaning up and running.
You need to define what you want to learn CNC technology for. If it is for a job, find a well respected school near by that has a good placement record.

If I go with a router I will have to buy the mills also so this ups the cost. Will I be better of just doing the mill, and hang on for the ride?
Huh! The cost of a 1/2" cutter is nothing compared to building a CNC router. Further you say you have a mill already, just use the 1/2" tooling from that machine. You aren't going to build a CNC router for nothing.
What would you do?


Sit back and reflect a bit. Building a CNC machine of any type can be a good learning experience but what you will learn isn't for the most part CNC machining technology. A good portion of the stuff you need to learn to effectively use CNC equipment is focused on CAD/CAM.
 
Starting off thanx to everyone who responded. I know zip when it comes to cnc. Anything that is needed will be learned as I move thru the project. Many if not most of the cnc build logs I have read seem doable. The mechanical side I'm pretty positive, the computer not so much, the electrical I will need as many diagrams as I can get :D. I am looking at cad/ cam now to get a head start. Maybe a year before actual build, as I collect all the needed parts.

As for learning cnc, this is what I want
1. To have it:D:D

2. To teach myself something that could possibly lead to better job prospects.
I have been disabled for the past few years and although this started as a hobby, I noticed I could maybe return to work doing cnc computer designs somehow. I know this is a steep hill but aren't they all it seems.

3. Is maybe make prototype ideas I come up with.

My learning style is read once then do... Most of the time:D. Cad cam will be the hardest for me I agree. My thought is we all had to learn it, so maybe I can. So with an understanding that the programs are way more advanced for professionals. This may give me a foot in the door, and look at college in the future.

What I'm worried about is the machine going bezerk while I'm trying to figure it out. And of course it will. But can I stop it.The prices for controllers, motors, etc.. are not cheap. With the large power motors is where my ?s are centered.

If I buy cnc kit for a router I will also need to spend money on the big mills cnc kit. Which is an added cost that. Or just build the big mill and hang on for the ride.?
 
First of all I am one who jumped in and converted a mill mostly successfully to cnc.
I was experienced in that I had some professional training on running a cnc mill and had run a cnc lathe for several months.
I have been trained by the USAF as a machinist and the army and navy in electronics.

What you are saying is you want to learn cnc.

Building/concerting a machine is doable, buy simply a small piece of the picture. as others have said you also need to be able to sanely program the thing. speeds and feeds are huge . the programing needs of each machine vary.

Setting up a cnc machine is not cheap to do it well. and software will likely cost a smuch as the hardware electronics.


the good news is most software you can download and try for free.
so where to start.


Cad try using autodesk's 123D design


V carve and CAMBam seem to be the most popular and most affordable CAM packages.

Mach 3/4 is probably the most used cnc software
Mach also offers wizards a conversational programing tool.

IRRC all of these programs allow you try before you buy.
Tin
 
Starting with CAD, I can recommend Draftsight, which is a free download. Plus there are plenty of online tutorials. Work through a couple along with the tutorials. Then you can download some of the engine plans you can find for free on this site and others, and draw some of the parts from the plans. After a while you'll find it's second nature.

For CAM, I use CamBam, and it does everything I've ever needed to date. Pretty easy to use, and a good support forum to help through the learning phase. There are also a good number of tutorials.

When it comes time to make parts, there are techniques available to help avoid disasters. First, run your programs cutting air and/or single stepping. Second, you can use machinable wax for the first run, although my preference is to use a simulator. I use Cutviewer Mill on all of my programs. Finally, you need to understand feeds and speeds to avoid tool breakage. I use GWizard, and it's worked well for me.

I'll also state that for model engine building, I spend as much time operating my manual mill as I do the CNC mill.
 
Learn to run a CNC for fun. You might be disappointed if you learn how to run it for employment. In W. Michigan, CNC jobs can be found all over. The last shop I worked at, they were taking anybody that could pass the 8th grade math test required for minimum consideration. If you were lucky, you could work for a temporary service for as long as you would tolerate not being hired in. Wages were between $9-$12 per hour. The set up guy made better, but there was on of him for 15 operators. It's changed a lot from when I first learned to program and operate. Now, there is a lot of button pushers, and one true operator.
 
If you are contemplating building a CNC mill, then think about the overall costs rather than just kits of bits.

I have gathered together everything to build a CNC mill based on a Sieg SX2 Plus mini mill, and it has cost just over £1400 (about $2,000), that doesn't include all the machine modifications and parts to be made, so any larger than that, the costs will go up proportionally. Not a small figure to be sneezed at if you find you can't use it.

I am in the same sort of position as yourself. The older I get, the retention factor diminishes, so the learning curve gets harder as I go along.
I am lucky in that I have a very good friend who is 'into' CNC, and he will be holding my hand as I proceed along each step. I am sure there are a lot of things that I don't need to know, and hopefully he will be able to show me the things I do need, if that is the case, I should find things a little easier than doing it all myself.

I would suggest you try to find someone like my friend, who can help you with hands on training to reach your dream, as long as it doesn't cost them anything, you should find that model engineers are very helpful people..

Best of luck with your project


John
 
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