PDA

View Full Version : Meat and potatoes of CNC for beginner



Infinity
02-17-2014, 02:45 PM
I've read Gwyn's tutorial and Wendy's intro into the CNC world and want to get involved making my own panels. In a nutshell, I still don't have a clue.

Is there a book or tutorial available for an absolute beginner? Something that explains the hardware, software, drawings, downloads, and how to put it all together. And by that I mean flight simulator related.

No Longer Active
02-18-2014, 01:04 PM
Well, I am no expert but I have a basic grasp of it, and has had stuff cnc'ed for me in the past.

I think with CNC you get what you pay for, the more you pay, the better quality the machine is and the more accurate it can cut (tolerances).

You obviously need to start somewhere and buy a machine, I think building one is too much for a complete noob as you need something that you can trust right away and learn, without having to know too much about the mechanics and internals by building your own.

I Dont own a cnc machine but I would go about it this way.

Buy a machine, read the manual again and again and again, and learn how to test the steppers and spindles,moving all the axis, until you are happy that the machine is working by using a computer. I would use the free version of Mach3 to test the machine. If there are problems testing any part of the machine, I would read the manual on both Mach3 and the CNC machine until I can get to the specific problem. I would also learn what all the settings on the Mach3 configuration page mean, and what I don't really need to know.

Once I am happy that I can jog the axis and test the spindle using the computer and I am familiar with the settings on Mach and what they do, I will attempt to run the machine without a tool and to run the machine.

I would draw something very basic on Cut2d, I would also need to learn how to use cut2d, I would watch the cut2d videos on how to use the program. On cut2d I would then generate the G-Code which it does for you on cut2d.

From there I would copy the g-code of my drawing to Mach and run the machine, we know the machine works because we have already tested it. The machine would hopefully run as per the g-code command, and if that worked I would then apply a cutting tool and test it on the material to be cut.

At any stage if I wasnt too sure of something I would ask questions on forums and I would hope that there would be someone to help, or maybe some support form the cnc manufacturer.

Above is just how I would go about it, others obviously do it differenty.

I would probably draw my panels on corel draw, then copy to Cut2d, generate the g-code, copy to mach and then run.

There is a really good Cut2d demo which is free, download it and have a play, watch the videos on the website as it will teach you how to use it. This will at least give you an intro to part of the software learning curve. Id start with cut2d if I was a beginner because it is cheap, however cut3d is more advanced, but considerably more expensive. Cut2d is ideal for contouring, profiling and pocketing. You can also engrave text using cut2d.

Cut2d = $170
Mach3 = $175
Your prefered drawing program = ie coreldraw = $25 per month subscription or $300 - $400 full program
CNC Machine $????

I Hope this gives you a little more insight, and good luck with your venture!

Alex

Infinity
02-21-2014, 02:09 AM
No one else? Thanks Alex. I appreciate the info.

Buddym
04-12-2014, 11:46 PM
Late post I know, but.... I went this route way back when. I built a CNC machine from scratch, using plans I bought on eBay for $25.00. The machine worked well, but was much too slow for cutting plastic. I ended up buying the Probotix Fireball kit. It is an excellent machine and still serves me well. I use BobCad and Mach3. By far, the most difficult task for me was learning to do simple 2.5 D CAD. I am pretty good at it now and can make most parts I need. The things I would suggest you focus on would be CAD and machining basics. You can't cut what you can't draw. The video tutorials available for BobCAD helped me a lot to learn about toolpaths, profiling, pocketing, etc. These are the simple things that I knew nothing about, but learned quickly. You will also need to know about single-line fonts for engraving legends on your panels. Study the feed rates and spindle speeds for the materials you work on. Most plastic likes a low-speed spindle and a faster feed rate. Learn about single-flute up-cut spiral bits, Onsrud has plenty of data on this. Solid carbide bits cut better and last longer than steel, but cost a lot more. These bits take a bigger bite of the material, and then eject it upwards, carrying heat with it. This is called chip-load. Also, learn to be patient. Making 4 or 5 passes on a panel might take a while, but adding 10 or 20 minutes to he cut time is much better than adding $35 and 5 days for a new router bit. The .0625 bits cut very well, and an bee fun in both steel and carbide