What can a CNC machine make?
A CNC machine can make a huge amount of things. As time goes by I see more and more things and more and more elaborate designs for really complex objects made by CNC machines.
CNC machines with an engraving spindle can make all sorts of pictures and text on wood, plastic and even soft metals. Lots of hobbyists use them to make and personalise craft things like phone cases, coasters, signs and nameplates.
You can easily engrave text into the wood so any sort of personalised house name and number sign is possible. Just imagine the thousands of different signs alone that could be produced just out of small bits of wood. Loads of stuff could be made just from freely available offcuts.
Once you have something like a router on a CNC machine you’ve got something that can cut wood, plastic and metal. It will also do it to a level of accuracy that could only be imagined a few years ago by a hobbyist.
Not only is it accurate but it’s a lot quicker than you could do yourself for intricate shapes and it’s repeatable. You just take out the finished item put in another piece of material and run it again for an identical part.
A CNC machine with a pen can draw on almost any paper and card and once you have a design it will reproduce it at the touch of a button you can do all sorts or personalised cards, pictures and maps.
With specialist pens mounted you can easily draw on fabric so you could draw text or pictures onto T shirts.
You can get diamond drag engraving bits for CNC machines, where the bit doesn’t revolve like other engraving tools, but simply “drags” over the surface of the material as the diamond engraves the surface. This can be used on glass and metal, again almost any design of combinations of pictures and text can be achieved.
Making PCB’s
One of the things I bought the 3018 CNC machine for was for making one-off custom PCBs. When I first saw CNC machines I thought there must be a way to use one of these to make custom PCBs. The first idea I had was to use a PCB etch resist pen to draw the design onto a blank PCB and even though
I never got around to trying this method I’m sure it would work for small boards as I’ve seen people make simple designs by just hand drawing onto blank PCB material with an etch resist pen. At least by using the CNC as an etch-resist plotter you would get repeatability.
Another way came along that cut out chemical etching and drilling. This way uses engraving bits to cut away the unused copper from a design and then you put a PCB drill into the CNC to drill the PCB. Some people even put an outline on the design and have the 3018 CNC cut out the PCB.
If this is something you want to do there are a few different bits of software that you can use on your CNC machine to make the design of a milled PCB easier along with mapping out the height of the bare copper board material so the engraving is as accurate as possible.
Making plastic boxes with a CNC machine
This was another attraction for me for getting a CNC machine.
I noticed a few electronic kits that were on eBay that came with flat plastic transparent Perspex boxes for the project like the one for the oscilloscope project. They came with all cutouts of various sizes and fitted together into really quite strong and attractive cases. Upon closer inspection, they look to be laser cut from a 3mm plastic sheet. I wasn’t too keen on the laser cutters, to be honest.
Reading some of the reviews about water cooling and fumes didn’t seem to make it very home friendly and a small desktop 3018 CNC machine looked more attractive. It also looked eminently possible to cut 3mm plastic to the size and accuracy that I wanted. After a bit of experimenting, I was able to come up with a decent project case.
This case is made from the internet files for a synthesiser. The material used was gloss black acrylic
All the parts were cut with the CNC machine. I would not be able to manually make anything near to this. I’ve also used the laser to engrave the text on the front and back panels.
If you look closely at the pictures you can see that the panels interlock. This makes for a very strong case. The pine ends were also cut with the CNC, then sanded and varnished.
You can also use a CNC machine for cutting those ABS plastic cases that you can get from most electronic component suppliers. After building a few projects that meant I had to cut square holes in these cases, like mounting slide switches. I dread to think of the times I’ve spent drilling and filing to get panel mounting things to fit.
Once you’ve designed a cut out in software you can test it on scrap material until it’s right and then build up a library of cut outs that are frequently used that you can cut and paste into new designs. Cut outs for slide switches and IEC power sockets are amongst items I can just pull out of my built up library to paste into a new design confident that the CNC will easily produce an accurate hole.
You can also use a low power laser to engrave text onto the plastic. Just experiment first to see what power and how slow the speed should be and once you’ve experimented you’ll be able to produce consistent results.
If you are a beginner looking to buy something like the 3018 CNC machine I have another article that you can read here.