Start here!
So you are interested of building your own Raw1.5, good choice a CNC machine is as obvious as an
y tool in your workshop. If you are buying a
larger commercial CNC you will have to spend 10.000 ds of euros even if
you only need it for
simple jobs so building one will save you a lot of money. A smaller machine is stronger and perfect for tougher
work like aluminum cutting and
hardwood. The bigger machines will also be good for this but needs extra support. You can read our articles on how to build a larger Raw 1.5
Where to start?
You need the source files and the plates, you can bu
y them
here: http://rawcnc.com/product/raw-1-5-source-files/ After that you just need
to follow the instructions here:
Instructions for Raw 1.5
Is it difficult to build the machine?
Not really, if you are somewhat handy it will be no probl ems , just follow t he vid eo instructions and study the exploded drawings of the machine. I have had customers who successfully built our machines with their kids and
without any experience at
scary but it’s easy, we will explain it all and you only
all. The electronics might seem
need to follow our tutorials. All parts are
drilled and cut in the right dimensions. If you are unsure you can buy one of our pre-built machines. What does it cost to build the machine?
This is a high-quality machine with real parts, no plastic wheels or weak timing belts like the other machines out there. If
you follow the BOM list with the links
we suggest the machine
frame will cost around 8-900EUR, if you buy some parts at eBay for example you will save 100ds of Eur. Many of the parts can also be second
hand without reducing the quality of the
machine. What can i cut with a Raw 1.5 You can cut almost anything, we use the machines daily to cut parts for other machines. We cut
Aluminum, Plastics and wood. Look at the videos below this page to see the machi thick aluminum. 15.000mm/min jogging
https://youtu.be/8nU61qK9SzI
ne cut 8mm
https://youtu.be/ylVz90jCkJ4
https://youtu.be/nYn9i88E7e8
https://youtu.be/f0UTFNObUVo
https://youtu.be/i7Z4xe7ivF8
https://youtu.be/q7y9qoWAn4U
https://youtu.be/iRkqKkjPajU
https://youtu.be/Eyudlmp_pAE
All the instruction videos on how to build the machine can be found here http://rawcnc.com/raw-1-5/instruction-videos-for-raw-1-5/ You will also find them and many other videos on You tube NOTE, all instruction videos are in English and the source files are in English and Swedish only. Raw 1.5 Professional CNC machine DIY kit 990x990mm Source files
Raw 1.5 is an updated version of the popular Raw 1.3 machine. The big difference from 1.3 is the strength of the machine with double the thickness of plates and stronger construction. You can choose to have belt or racks as drive, both are good but racks make the machine a bit stronger. A real CNC machine
This machine is very strong compared to the other DIY machines in this price range. The machine has steel reinforcements and quality parts and a real Z-axis construction. A complete Raw 1.5 weights around 50-60kg and is not made from weak plastic parts and 6mm thin timing belt. The machine has 6 safety, calibration and home switches and Z-axis touch of plate. You can equip the machine with Racks or timing belt. This is as close youwth canacome to a “real” CNC machine in this price range. What canas i cut Raw 1.5
You can cut almost anything, we use the machines to cut all the parts for your machine. We cut Aluminum, Plastics and wood. Look at the videos below this page to see the machine cut 8mm thick aluminum.
Is it difficult to build the machine?
Not really, if you are somewhat handy it will be no problems, just follow the video instructions and study the exploded drawings of the machine. I have had customers who successfully built our machines with their kids and without any experience at all. The electronics might seem scary b ut it’s easy, we will explain it all and you only need to follow our tutorials. Is it difficult to operate the machine? It’s always tricky to do something new but
after you have cut your first piece you will get a hang of it. It takes us a few minutes to setup the files to have them cut. Once you know how to do it, it’s easy. What does it cost to build the machine?
Thisthe is aother high-quality machine withIfreal weak belts like machines out there. youparts, followno theplastic BOM wheels list withor the linkstiming we suggest the machine frame will cost around 8-900EUR, if you buy some parts at eBay for example you will save 100ds of Eur. Many of the parts can also be second hand without reducing the quality of the machine. On a budget? Do you like to build the machine but bigger? or are you upgrading?
No problems. just buy our plates or drawings with BOM list and you can do what ever you like. If you have a Raw 1.3 you will be able to use most of the parts to upgrade, the differences are the plates and the thickness of the Y-axis that is 80mm instead of 60mm. To upgrade you need to purchase the new plates and wider X-axis profiles from 60mm to 80mm. The plates are avalible as a separate product. The electronics
Many of you prefer to use your own electronics instead of the one we suggest and you can do what ever you like as long as the motors are standard nema23. We recommend that you buy the electronics from eBay for example, it will be cheaper for you. The download contains a detailed list of the electronics, both a profesional and a budget version, USB or printerport controlled. The electronic box seen in the instructions can be cut after the machine is built, we also include the .DXF files for the electronic box and you can modify it to fit your needs. There are .DXF files for arduino card and Drivers box. You got a CNC machine after all, so why not cut it yourself. Belt or Racks?
You can choose to build the machine with timing belts or racks. Timing belt and 3 x pulleys is a good choice up to a certain length of the machine. Its recommended that you change the belt to racks if your machine will be longer than 1 meter to avoid “backlash”. Belt has a good precision and is both cheap and fast. Racks and 3 x pinions are better since it has less back lash and good speed but are more expensive. You should consider racks if you are planning to build the machine bigger or if you are cutting harder materials like Aluminum. Threaded holes The plates and some of the profiles need threaded holes. For this you need thread taps in size 4,5,8 mm. This is not dif ficult. Buy qual ity taps that do not s nap. If a t ap snaps in a hole, it’s almost impossible to get it out. The download includes a thread blue print. Bigger machine?
Yes you can build this machine up to 130x200cm, go here for instructions : http://rawcnc.com/raw-1-5/how-t o-extend-a-raw-1-5-and-reinforce-it-w
ith-steel/
Spindle or router
Choose a professional air-cooled 1,5 KW spindle with inverter for professionals or a standard router. We will include suggestions and also links to a professional router or a budget version. If you choose a professional spindle we will have wiring instructions for you in ther download aswell. Precision Precision is a balance between user and machine. It’s all about how good your
drawings are, spindle, rpm and how fast you cut. At a normal speed of around 2-4000m / min, the machine has a Measured precision of about 1 /10mm This machine is the result of many years of development. We have cut several thousand meters’ materials with machines like these and done that daily for many years.reinforcements Steel The size of the steel bar in the x-axis bar is 40x60x2mm and 80-100cm long (80cm for belt drive and around 100cm for racks) The machine is stable as it is, the steel reinforcements are optional. If you are planning to cut hard materials then please consider the steel bar. The small wedges on the side plates are not necessary, the plates are thick and they are not needed. Payment
We use Paypal and your download will be avalible directly after you have purchased the files. If not then please log in to your account and download them from there Size of the standard machine is: Width of X-axis : 990mm (1225mm total), Length : 1000mm Cutting area: 765mm(width) x 720mm(length) Clearens under the z axis: 125mm
To build the machine you will need
A stable table atleast 1x1m
Power drill
Drills 4-8mm
Solder pen
A set of hex keys
A set of Screwdrivers
A set of wrench keys
Clamp
Metal file
Electric tape
Electric socket for the power supply and approximately 2 meter grounded cable (Not included since all countrys have different standards. You will find it in your local hardware store) NOT E: the kit includes wiring of high current between the power sup ply and the electronics. This must be done by someone experienced. High current is dangerous. We do not t ake responsibilitie s for faulty wiring or injuries. The wiring from the electronics to motors and switches are low current and harmless. To operate the machine you need:
Mach3 or 4 software (Demo avlaible) CAM software like V- carve. There is many free CAM softwares, just search for ” Free Cam software” A spindle or router and some endmills. We endmils and use larger ones for clearing.
recomend that you cut with 3-4
mm
A computer with a 32 bit operating system and printer port. The operating system can be downloaded for free or you can buy it on ebay for 10EUR or so All thehttp://rawcnc.com/raw-1-5/instruction-videos-for-raw-1-5/ instruction videos on how to build the machine can be found here You will also find them and many other videos on You tube Here is an example on the instructions on how to build the Raw 1.5 machine. When you receive your package, you will also get exploded drawings and additional instructions
https://youtu.be/FzRdcSjJb4Q
https://youtu.be/8nU61qK9SzI
https://youtu.be/ylVz90jCkJ4
https://youtu.be/nYn9i88E7e8
https://youtu.be/f0UTFNObUVo
Instruction videos for Raw 1.5
Instruction videos for Raw 1. 5
Here you will find all instructions on how to build the Raw 1.5 machine. You can also look at all the exploded drawings that comes with the package to see how to build the machine. As a customer you will also get downloadable files with more instructions for each video and close ups. Download your files, The link is in the welcome letter, here you will find instructions for setting the spindle, autotool and much more that are very helpful when building the machine. There is also a complement file for some of the videos that are very helpfull. For arduino users
If you have choosen Arduino as electronics you also need to look at the instructions on how to build a Raw S-70 that you find here: http://cncmaskiner.org/instruktioner-raws70/ But only when you reach Part 9. Then follow the Raw s-70 instruction Part 8-10. You will also find instructions on that page on how to setup the software. These two machines are almost the same exept for the right calibration switch that cant be used for Arduino. To set up Autotool for Arduino you need Estlcam software that has this function. Part 1 Raw 1.5 preparations
Thread instructions will be avalible in the download that comes with your package
https://youtu.be/aZqGrFdHc5w
https://youtu.be/9yI1Cr6Giy8
Please use a 3.2 or 3.5mm drill instead of a 3mm drill to fasten the Screws to the steel bar, apparently the screws snaps easily when the hole is too tight.
https://youtu.be/i7Z4xe7ivF8
https://youtu.be/q7y9qoWAn4U
https://youtu.be/iRkqKkjPajU
https://youtu.be/Eyudlmp_pAE
https://youtu.be/FzRdcSjJb4Q
https://youtu.be/C09xQf8obfY
https://youtu.be/5rF3c_uElOk
https://youtu.be/hAxVjg__dGA
The videos below is for the Arduino card. Its done on another machine but the wiring is the same. Note: If you are familiar with shrink hoses, use that instead of electric tape it’s both safer and better looking. Another tip is Cable Spiral Wrapping, that makes everything look better. All should be included in your kit Part 9: Connecting the Arduino card
The thing you should look for in the first video is how we connect the RGB cables to the end of each motorcable, We will use them to connect the Arduino card. If you have a electronic box with DIN pluggs, then the RGB cables should be connected to the female plugs instead. Look at the video and you will understand. You can skipp the DIN plugs if you like, they are not necessary.
https://youtu.be/l1zhkNK9d6o
https://youtu.be/GH9p0fY0E38 WARNING:
When placing the small heatsinks on the drivers, make sure that they are in the center of the small chip. If the heatsink touches the small potentiometer or any other electric parts the card will be damaged
https://youtu.be/4kPyvCUgV9w Setting up the software (Mach 3)
No video is required for this part, all machines are different and depending on which electronics you use, you must follow the manufacturer’s recommendations. We use high quality drivers and the settings for these are available in your download. You can also use our preprogrammed setting file (Mach3Mill.xml) that you replace with it in the on in the Mach3 folder. All instructions are found in the download. For arduino you will see everything you need in the link we refer to during the construction. Software For Arduino , we recommend Estlcam as well as a 3D or 2D program like Google
Sketch up or CorelDraw. Drivers require 3 different softwares to run the machine, 3D or 2D software, a CAM software (set tools and depth, etc.) and a control program (Mach3 or4)
3D or 2D we recommend Google Sketch up or Corel draw. There
are lots of options
and everyone works as long as you can export your fil e to .DXF or .STL format. CAM software, we recommend Estlcam or the more expensive Vcarve.
As control software, we recommend Mach3. Mach3 is enough and you do not need Mach4. We only have Mach3 settings so if you upgrade, so you must manually set Mach4. Set Autotool, Spindle, and Homing functions.
We refer to our downloads where you will find everything you need. As a customer, you also have personal support, just contact us if something is unclear. Now you need to learn how to cut with your machine, go to our artile pages and look at the instructions on how to cut and setup your tools. start with this link http://cncmaskiner.org/skara-ut-delar-fran-borjan-till-slut/
Back to School
We use so many different settings, belt, lead screw or racks in different sizes so I will put out a tutorial for you so that you can calculate this yourself. If you use Arduino and GRBL the math is different to Estlcam or Mach3 for example, lets start with GRBL that asks for a PER mm number:
GRBL (Estlcam settings below this article but read this as well to understand what we are looking for)
A typical stepper motor has 200 steps PER revolution. These are known as FULL steps or 1.8 ° per st ep. A Raw machine has a HDT3 or HTD5 timing belt which means that they have a pitch of 3mm 5mm. Pitch is thethreads, distance between two tops orasbottoms of the or theor distance between if you use leadscrew we do for the timing Z-axis.belt/racks If you want to calculate a leadscrew then the math is simple just add the pitch of the leadscrew 3mm and divide it with 200 (stepr per revolution) and the number we will put as a value in GRBL (The settings in GRBL call for a PER mm number) for example is: 200/3 = 66,66666666666667 steps to make something travel 1mm For timing belt we need to calculate how many teeth the pulley has and multiply it with 3 or 5 depending on the pitch, so for a 5mm pitch and 15 teeth (5×15) , then it will travel 75mm/rev So the math is : 200/75= 2,666666666666667 steps to make something travel 1mm
Micro stepping (Estlcam for exampl
CNC shield w ith the A4988 Drivers uses 1/16 micro stepping when all jumpers are activated , which means each step is divided into 16 microsteps. A typical stepper motor has 200 steps PER revolution. 200 steps x16 micro steps = 3200 total steps/rev So the value “steps per revolution” in Estlcam is 3200. If you use other drivers that has 32 micro steps that value would be: 200 steps x32 = 6400. “Distance per revolution” is what your machine will travel per revolution so for a HTD5 belt (5mm pitch) with a pulley that has 15 teeth that distance would be 15×5=75mm -HTD3 with a pitch of 3mm would be 15×3=45mm -Lead screw with a pitch of 3mm will travel 3mm per rev and that would be 3mm The same math applies for Mach 3 but we need to extend it some more Mach3 or other software’s asks for how many steppes it takes for something to move 1mm, so let’s do the math with the lead screw that has a pitch of 3mm (it travels 3mm
per rev) We use 16 micro steps setting on the drivers for the z-axis so the math is basically, 1600/3 = 533,3333333333333 steps to make something move 1mm (again, if your thread is different, then the divider number will be different) 533,3333333333333
is the number I put into Mach.
Build your own machine There are several ways to tackle the task. One is to seek out various forums and look for drawings and good advice. I’m the type who dives into projects and cannot be bothered to go slow, but I have found out that errors are very expensive in the CNC world and I wish I had read a text like this when I started, that would have saved me a lot of money. We who built a couple of machines know that it may take a few machines until you get it right because there is a lot thinktoabout. build a machine that travels back/forward and up/down is to easy, build aTo machine that has precision and good speed is harder. A CNC machine can be as complicated as you wish, it’s up to you.
Where to start?
What do you want to do with your machine? Are you going to cut paper, decals, aluminum or wood, three-dimensional or two-dimensional with simple plug holes? Or do you want to build a machine that can handle all of the above? Sounds pretty difficult? No worries, a homemade CNC machine can handle the above if you construct your machine the right way from the beginning. Everything is really about construction. The electronics are easy since everything is available for purchase. The design however is more difficult.
My first machines were made with MDF and plywood, this is good since it is cheap but the machines aren’t good in comparison with a steel or aluminum machine. Below is a video from 2010 on one of my machines entirely of wood. This video makes me smile, a lot has happened since then. If you look at the background to the left of the wooden machine you can see my first aluminium machine, that was the beginning of the Raw machine. I myself was inspired by buildyourcnc.com. He who runs the site builds its machines in MDF and plywood. I built my first machine with ideas from this page. But… these machines are good up to a certain point, wood bows and hangs over time as it is a living material. Materials
I would only recommend aluminum for the person who will build its first machine. Steel Machines are better but much more difficult to build. Everything must be cut in mm precision and this is difficult with steel that needs to be welded. Aluminum is very grateful because it is a straight material and easy to cut and join together with various accessories. The disadvantage of aluminum is that it is light and has more vibrations in the construction. An ideal machine should be robust and built in a heavy material like steel that “absorbs” vibrations better. But if you ne ed the machine for simpler tasks with about 1 mm precision then aluminum is an excellent choice. You can even get an aluminum machine to engrave jewelry as long as you run it at low speed.
XYZ Axis
A three-axle machine should be able to move three-dimensionally in the direction XYZ sideways, back and forth, up and down. This must be done with as little friction as possible. There are different ways to solve this. That is, how will my axle “roll / glide” on these directions. Because it is expensive to build a CNC machine most of us are looking for inexpensive solutions. My first solution was to use ball bearings that slide on a 90 degree angle like the picture below.
This is extremely cheap but not so good. The problem with this solution is that when you drill the holes in the an gle it’s really difficult to get it symmetric, if one hole is a little bit off, then one of the bearings won’t touch the angle and there will be a “gap” in the design. If you get the holes right then it is important to get the tapper right in all holes as well. I like the idea, it’s a s imple design but if you are looking for a more professional build you should look at another solutions to. My second solution was more expensive, I bought the V-grove ball bearings from the US for 12USD each (you need about 16pcs). This is what i have on the wooden machine above.
I had these bearings sliding in the same way as the first solution (on the back of a 90 degree profile). This works ok but it will wear the profile down after a while. I simply had to give up my budget ideas and seek for more professional solutions. I bought Linear ball bearings and shafts like the ones below:
This is very expensive, and the precision shafts are really expensive. This solution looked really good in the beginning. Unlike many others, I used my machines for cutting furniture’s daily so they were exposed to a lot of saw dust. W hat happened was that the dust found its way in to the bearings and made them useless. This can be solved by having the bearings below the table but I gave up the idea. I tested a lot of other methods and the last option was to buy similar linear units as above but with block bearings that slide on a flat steel bar. This is the best solution but extremely expensive and I thought that there must be cheaper solutions out there. So instead I went back to my first solutions to have something rolling on an axle that don’t need to be lubricated since lubrication a nd saw dust don’t work well together. And I found it… The concept is to have a quality u wheel of steel (not plastic) rolling on a precision rod and clamp profile. The dust has a very little chance to stay on the thin 6mm shaft and this solution don’t need any lubrication.
If anything can be worn it’s the
precision rod/ax le but it is very easy and inexpensive to
replacethat in comparison withmachine. other solutions that let onthe theprofile actualalso profile is a part of the The beauty of the thisbearing solutionslide is that becomes a part of the design. A machine with this system may look like below. (click to enlarge)
For me this is a cheap and about the costs. Propulsion
good solution. There are of course better solutions but
Now we need to figure out how to move the axles, there are different
Trapezoidal screw
Ball screw
Rack and pinion
Timing belt with pulleys
Chain What we’re after is a machine that has High speed (if as 0 or very little backlash. Pros and cons: Trapezoidal :
it’s all
solutions.
desired) with much force as
well
has a low speed and the pitch usually does not exceed more than 4 mm per revolution, ie the motor must rotate once for the machine to move 4mm In this way you can get the machine to go in about 1-2 meters per minute faster than this requires a higher pitch of the screw or more po werful motors. I recommend this variant to machines that don ’t need to go fast, and to your machine’s Y -axis (up and down) even if you are running with timing belts or other solutions. With this solution you will have a very low backlash and a relatively inexpensive solution. Protection against dirt = bad (have the screws on the side or underneath the machine) Backlash = Good (until it wears)
Ball screws:
as above, but much more expensive. A screw can go for several hundreds of Euros and you may need 4 pieces. Here you will gain higher speeds maybe 3-4 meters per minute. And up to 0 in backlash. If you are working with wood or larger pieces this solution is painfully slow, it’s more suitable for small objects like aluminum or en gravi ng jobs. So use this if you require precision and decent speed. Protection against dirt = Ok (have screws on the side or underneath the machine) Backlash = Very good, and probably the best option if you need as low backlash as possible
Rack and pinion:
Now we’re talking, a rack has both speed, power and low backlash. My last machine that served as my workhorse were of this type. I also turned the gears downward so that dirt cannot get stuck between the teeth. More disadvantages are that the teeth wear out if you don’t find quality steel racks. And nice racks are hard to find as in real life. With rack and pinions you will come up in ridiculous speeds with enormous forces. This is the perfect option if you are really going to work with your machine. I will bring up a CNC machine with rack and pinion in the near future. Protection against dirt = Very good (probably the best solution) Backlash = Very good (If you find high quality steel Racks)
Timing belts:
Timing belt can be good or bad depending on how you use them. I have seen many projects that builds CNC machines with a G2 timing belt that is 6mm wide. These are like rubber bands and are only suitable for 3D printers, decal and paper cutting machines. The backlash with a 6mm belt must be brutal. I use timing belts for my machines as well but these are HTD3M belts 15mm wide and with a steel core. These work very well and you can even turn the belt upside down to avoid dirt. I like belts, they are cheap and easy to replace. As with the rack you will get speed and strength and very good accuracy. I recommend you to use belts for your first machine. Protection against dirt = Very good Backlash = Good (with wide belts)
Chain:
I have had machines with chain drive b
ut they dont work good,
I do not recommend
chain…
Let’s move on…
Z axis
The Z axis is the one that goes up and down. This axis is the hardest to design. It must have both precision and withstand extreme stress, moreover, it must be small in order not to be in the way. Add a lot of effort on the z axis.
Milling spindle
You can use a simple router or an expensive air or water cooled spindle with inverter. I usually go with the best as it is here all the action takes place. A bad router/spindle vibrates and it shows on the piece you are working on.
End mills
There are many different variations, H SS Cobalt, Carbide, 1 flute 4 flutes etc. Number of flutes depends on what you are cutting. For example, when cutting in aluminum, you want bigger “Chips” because it is a soft metal. A 4 -flute end mill tend not to have enough space between the flutes to allow the material to evacuate, so they stick to the end mill and it won’t cut well anymore. In this ca se a 1 -2 flute end mill is better. A four (or more) flute end mill has more cutting surfaces at each rotation, so it gives a finer finish at the same speed as a 2-flute end mill, if you have a milling spindle with lower speeds with eg max 12000RPM a 4-flutes end mill will be perfect if you are working with wood. A 2 Flutes end mill will also work but it cuts a little rougher but still good. The only way to find out is to try out on the machine you have.
Electronics
There is so many varations that i need to do a separate article about this, but a Raw machine uses a 4 axle electronics kit with 4 normal (around 8cm long) nema 23 motors with at least 1.9Nm or 270oz-in
There are many users that hates the tb6560 board but I love them, simple and inexpensive. I have had no trouble at all with these boards. The green Raw Demo machine has the same tb6560 electronics that I bought back in 2011, and they have been working almost daily since then. I bought them from Wantai motors on Ebay. I also bought other electronics with traditional drivers but they have burned up long time ago. What else… Software,
Its a jungle, but the principle is, To run a CNC machine so you need to write data to the machine as G code. The process may look like this:
Make your 3D drawing in any CAD program (there are good Google Sketchup or A9Tech
free programs such as
Import your drawing to a program that generates G -code you can use expensive software like Vcarve or free like the Sketchup plugin ScetchUcam Import the G-code to Mach3 to cut your piece. Read my article about software if you need to know more. Computer / PC
You need a traditional PC to run your machine, a Windows XP system works well. Reason for this is that the circuit boards require a printer port. Printer Ports on a Laptop will not do since they operate in a different way.
USB ports are on its way but it’s still a bit early, bu t in a few years USB will be the new standard, until then we have to stick to a traditional PC with a printer port. Hobby Machines
There is a reason that an industrial CNC machine can cost more than a car. Such machines has no margin for error, it has to work perfectly around the clock and all year round and that requires expensive electronics and parts. An industrial CNC machine also has many more features that most of us don’t need
A hobby machine is usually made with stepper motors and parts that is eas y to find. Even if it’s a “Hobby machine” These machines are not toys, they contain delicate electronics and has an incredible precision which surprises most people who see them, the machines cut into millimeter precision in all directions. A machine with sensitive electronics in a dusty environment requires maintenance and monitoring and that’s p robably the big difference between a hobby and industrial machine. What skills are needed to work with a CNC machine? As with everything else, it’s a learning proc ess. In the beginning it may seem tricky
when you suddenly can bring out things in 3D and you have to think threedimensionally. But as soon as you understand the concept it will open up a whole new world in production and manufacturing.
Raw compared with V-slot machines
Raw compared with V-slot machines
V-slot machines like OX CNC and X-carve or shapeoko CNC has a
similar appearance as a
Raw machine as they are all based on aluminum profiles in size 20×20 similarities.
-80cm but there ends any
A Raw machine is much stronger than any of the foregoing. The price situation is fairly even bet ween all models but Raw can b e sli ght ly more expensi ve because it uses real parts that can withstand the load.
Machines based on the V-slot concept has plastic wheels rolling in the groove of the aluminum profile usi ng a 90 degree wheel s on all axles . This sou nds cheap and clever but thi s w ill not work if you are cutting in harder materials. These machines usually have an weak drive with GT2 belts that are more suited for 3D printers and a Z
-axes with backlash.
These machines are good for those who want to learn the technique and u thin materials. You can see videos
se the machine to cut
of these machines cutting tough materials, but
this concept and it does not work well, unfortunately.
I have tested
You can build a ok V-slot machine if you replace the drive to stronger belts, screw or rack and replace the Z axis.
Another problem with the V-slot is that aluminum and plastic are weak materials, if you
get
aluminum shavings between the wheel and profile then both the wheel and the profile becomes damaged and everything has to be replaced.
The Raw concept
On the surface a Raw machine looks the same as the other ones but he
1. Drive. Instead GT2 belt that is more like rubber band a
re is the big differences.
Raw1.3 uses 15mm HTD3M
belt with steel core. Raw1.3 is also modular so you can choose to run it on racks or screw if desired. 2. Z-axis, this is probably the most important part of your machine. A raw machine a real Z-axis with steel rods and bearings blocks and
has
not plastic wheels and V -slot
rails. 3. Steel wheels and steel shafts. Instead of a plastic wheel into an aluminum track a Raw machine uses steel wheels that rolls on steel shafts. 4. Hidden motors, if you build a Raw with timing belts then the mopors are hidden in the X axis to protect them against dust and shocks. 5. Stronger X-axis, a raw machine has a stronger X
-axis with the potential to strengthen
the axis further. 6. You can work properly with your machine! I like the V-slot concept but not for CNC machines that is cutting harder materials. The Raw concept is certainly not the ultimate way to build a CNC machine, but as a budget machine in
the aluminum profile range it is a very good machine to own. If you are building a more professional machi ne, you should work wit h s teel and real beari ng block s and gear racks. I have one on the drawing table that I will present in the near future;)
Cutting parts from start to finish Work with your machineJanne
Here is a video of typical work flow when working with your machine. I use 3 different softwares to cut my pieces.
1. For 3D objects i use a free version of
Google Sketchup.
2. Tool Paths: You will need a “Tool Path” software, there is many free versions but i use V-carve 3. Mach3 or similar to send your instructions to the machine. You can purchase Mach3 on my www.cncmaskiner.org website.
If you are using Google Sketchup you will need a plugin to convert your 3D objects to .dxf format, go here for a free plugin that does this:
http://www.guitar-list.com/download-
software/convert-sketchup-skp-files-dxf-or-stl
If you need help with your drawings or preparations of your files i
can help you with that.
Contact me for more info.
4 motors on a 3-axle machine? CNC tips and tricksJanne
4 motors on a 3-axle machine?
As you may have seen most that build a 3 machine (up-down, left-right, front-rear) have 4 lead for the Z-axis (up-down) one
screws or belts and 4 motors. One
for the X-axis (left-right) and two for the
XYZ axes can be confusing. When we talk CNC machine the Z
-axis motor
Y-axis (front-back).
axis is the one that goes up and
down. The reason for using two screws/belts and motors for
Y axis is two or ma ybe three …
1. A machine with 2 lead screws (or belts) on
each side of the Y-axis will lock the axis
to a perfect 90 degree position. Since the Y
-axis has the widest span, it is technically
difficult to just get by with one motor and screw. You can get by
with one motor but
not from the two screws (or timing bel t) on each side of the machine. 2. The Y axis has to work harder than the others, so two motors is better than one.
3. Calibrati on. I personally think that the calibration of the
machine becomes easier with
two motors. We want all the axis to be exactly 90 degrees. With two
motors you can
have 2 Switches (home limits) and instead to calibrate the lead screws or belts, you can move one switch maybe 1 mm in any direction for fine adjustment. How does a machine work with four motors?
To begin with, you must have electronics adapted f
or a 4-axis machine. Everything after that is
done with software such as Mach3. What you do is to have one Y
motor as a Slave. In this way,
it is in sync with the other motor whatever happens. The only thing you should consider is to mirror rotation on one motor if you use eg belts. Either with cables or software.
How to extend a Raw 1.5 and reinforce it with steel Raw 1.5Janne
You can easily make a raw longer or shorter than the srcinal 990x990mm. This requires that some of the parts needs to be replaced.
To make a Raw 1.5 wider: All parts that has to be wider will be extended the same amount so for the A, B, C, D, E, you just add 20cm for example. If you already have a ma
F, G
chine then the shaft clamps can be
reused, just buy the amount that is missing. All other parts need to be replaced. If you are extending a machine you already built you might be able to
use some parts from the Y-axis for
the X-axis and the other way. You should also consider adding an extra base profile (F).
On an srcinal Raw 990×990 the measures are (also listed in your BOM list if you bought the plates):
A 990mm B 985mm C 800mm (If you don’t ha ve Belt drive the steel bar can go from plate to plate 990mm) D 580mm E 980mm F 950mm (Optional) G 980mm Just add 20cm for example to the above values exept for (F)
You will also need to replace the base table if you have a machine that you are modifying.
The X- axis don’t need any more reinforcements up to 150cm wide. If you are planning to make it wider then you need to fill the Steel bar with concreate or epoxy.
To make a Raw 1.5 longer: All parts that has to be longer will be extended the same
amount so for the A, B, C, D, E, G
you just add 20cm for example. If you already have a ma
chine then the shaft clamps can be
reused, just buy the amount that is missing. All other parts need to be replaced. If you are extending a machine you already built
you might be able to use some parts from the Y
the X-axis and the other way. For our pre-built machines that is longer than 1000mm w
-axis for e use
20x60mm instead of 20x40mm (E), but that is up to you.
On an srcinal Raw 990×990 the measures are (also listed in your BOM list if you bought the plates):
A 990mm B 985mm C 1000mm D 580mm E 950mm G 950mm Just add 20cm for example to the above values
How long can i make a Raw1.5? We recommend not to build it wider that 1300mm and longer that 2000mm. It’s diffi cult to find longer racks than 2000mmm and they bend to much if they are lon ger. Don’t use belt for machines longer that 1000mm, it works but only for cutting wood in low speeds.
Reinforcements for the Y and A axis The Y and A axis should be reinforced with
steel bars if you make the machine longer than
1200mm. It’s very simple, look at the image below and you will see how its done. We fasten the steel bar exactly the same way as we do with the X strong glue along with the screws.
-axis bar. You can also use silicone or a
As you can see our pre-built machines has bigger corner plates but you can still use the ones you have. Ours are bigger to cover the steel bar and our wider base. We also use bigger (MOD 1.5) but that requires more modifications. If you want to use MOD 1.5 you nee modify the parts by yourself. Another thing to concider is to have a support bar (B) in the center of the Y and A axis as we do
with our larger machines.
racks d to
