Copyright... Website created & maintained by GHQP
November 9, 2010 This is where it all started
This project is perhaps one of the most adventurious I have undertaken. It is the design and construction on a Flat Bed CNC Router. This week I received the linear rails, bearings, lead screws and antilash nuts. I have ordered two lengths of aluminium extrusion for construction of the bed. In addition to this I have been researching various designs styles and sketching various concepts of my own. On this page I will be documenting my progress. I expect the project will take a few months to complete.
November 10, 2010
Purchased flat bar aluminium for project and cut 2 end lengths for base end supports . Awaiting arrival of base side rail extrusions.
November 12, 2010
The base side rail extrusions arrived today but only one 1M length arrived instead of two at the lengths I specified when ordering them, very frustrating. However I did work on drilling the end supports for the extrusions. Also tonight I did further work on the construction sketches.
Been working on machining the base ends and further design sketches. I took my time marking out and machining the base end pieces as it is critical to get this right. Everything else rides on this so being flat and square is critical to the smooth running and accuracy of the finished router. The people I purchased the side extrusions were excellent and sent me another piece the length I required at no cost. So I just had to cut the 1M length I had already received to the same length. Having a metal Band Saw is so convenient for cutting aluminium bar and round, it saves a huge amount of time along with effort and the accuracy of the cut is excellent. I don't want to think of what I would do without it. So today I did a pre-assembly of the base and it's looking good. See pictures opposite. Next I will be checking my drawing dimensions and start on the gantry side supports. I am doing this stage by stage so that I can confirm my drawing & sketch dimensions before moving to the next section. Also I am sort of making up and refining my design as I go along.
December 5, 2010
These are photos of the X Axis Gantry construction Completed about a week ago.
December 5, 2010
These are photos of the Z Axis construction Completed this week.
December 5, 2010
I have been so fixated on the construction I have neglected to keep this page updated over the past few weeks. However Progress is rocketing ahead. I received the Stepper motors and controller last Friday and used the assembled Z Axis to test the motors and controller. It all worked perfectly. One of the motors arrived with some damage to one of it's mounting holes, the supplier in China is replacing this. Today for the first time I did a complete test assemble and apart from some minor adjustments it all went together superbly. I will post these and some other images tomorrow. It is really getting close to a fully functional rough test. Following this there will be much work to do with wiring, fitting the limit switches and building the MACH3 control computer. Anyway to date it is looking good. :-) I hope the photos above do justice to describing the machining construction process.
December 14, 2010
See the HOME page for first video clips of the working Router. I will update this page with more construction photos very soon.
Mounting the Spindle Motor. This is a 1.5KW 24,000RPM Air Cooled VFC Motor.
These are various photos showing CNC Milling of the Ball Nut Mount, Stepper Motor Mounting, Machining the Hand Wheels & a photo of the Stepper Motor Controller PCB.
Photos of the first all axis functional test. I used a standard Plotting Felt Pen mounted in a floating holder that I had previously
made for just such a purpose. As I had not yet received the extrusion for the router bed I found a suitable piece of laminated chip board. I used masking tape to secure a sheet of A3 size paper. With Aspire I created a series of test shapes and text that I used to compile some G-Code. I loaded the G-Code into the attached computer running MACH3 and ran it, you can see the results. On the home page is a video of the test plot.
The depth of cut was set to 1.0mm for all the routing as this is well within the floating range of the plotting pen holder.
The next step is to assemble the computer system, Stepper Motor Controller Card, Power Supply etc. into one nice self contained enclosure.
As of today (December 15th) this is well under way. I am expecting the special aluminium extrusion for the bed to arrive any day now. There is still cabling, limit switches and various other things to do before the machine will be ready for its first real routing test of a piece of wood. I don't expect this will be for a few weeks yet due to all the stuff I have to do for Christmas.
December 15th 2010 The photos below were taken over the past week.
This is the control computer. The Motherboard, HDD and Power Supply came from a neighbours computer that they had no longer any use for. I purchased a new cube style enclosure and was able to fit into it the computer components along with the Stepper Motor Control board along with its 24VDC power supply. It all came together very nicely as you can see.
The router bed is made up from 5 lengths of slotted Aluminium Extrusion. They are secured together from the underside. The top side of the extrusion has 2 T Slots per length and the underside 1 T slot. The 2 T slot side is perfect for the top as it maximises the securing aria for work material. This extrusion has to be purchased in 6 Meter lengths so that's OK I have 3 spares in case I ever damage any by running a cutting tool into it. That's always a good possibility with CNC.
These photos show the cabling to the Spindle Motor, Temperature sensor and Z Axis Stepper Motor. The temperature sensor display is on the front panel of the computer. It is important that these VFD motors don't overheat as they can seize up. For this machine I have used an Air Cooled Motor but they are also available in Water Cooled versions, I use a 1.5KW Water Cooled Spindle Motor on my Sherline CNC Mill. Water cooling has one big advantage in that the motors cooling fan and vans can't get clogged up with machining dust. I will likely swap the Air Cooled motor for Water Cooled one in the not too distant future. I already have one but will have to makeup the water cooling system for it.
Its a bit of an anticlimax when a three month project like this is nearing its end. However all in all it has gone fairly smoothly with only a few minor hiccups. I am sure I will be doing some fine tuning and modifications as I start to use it. I know I will be machining new side vertical supports. In order to get the maximum Y axis length machinability they need to be swept back by about 100mm from the bottom to the top. This will bring the centre line of the spindle motor back towards the centre point of the tables Y Axis. All going well I may actually even be able to use this router to profile out these new sides. It will be a long process as the blank material will be 200mm X 370mm X 12mm thick aluminium. This router is designed mostly for machining wood & acrylic so it will be a big test to profile out this big a chunk of aluminium. So we will see.
Aligning the Table level relative to the Z axis.
I fitted a row of M4 grub screws at both ends of the table, using these I was able to tilt the bed in both planes. This allowed me to set it up with minimal Z axis error but I wasn't happy with this as the primary method. So I then adjusting the side rails & extrusions. Drilling the rail mounting holes bigger gave me enough movement. (with all the grub screws retracted) First I set the Y axis from end to end at the centre of the table. Then I worked on the X axis one end at a time. When I got these as close as I could within 0.3 to 0.5mm I did the fine adjustments using the grub screws. I achieved a maximum error at full travel in the Y axis of +0.20mm and the X axis 0.15. I am sure I can get it closer spending more time on it, but for now and testing this machine this is quite good. In fact for most jobs this machine will be used for (in wood) this accuracy is well within useful limits.
December 30th 2010
Images showing how the axis limit switches are fitted. They work in that if for some reason any axis gets out of control and is about to hit the end of its travel the switch activates about 1.0mm or so before this and causes MACH3 to issue a stop command. This will hapen under G-Code program or manual control mode.
Computer with new 10" Touch Screen Monitor and wireless keyboard.
The routers mechanical construction is now almost complete. There is still some finer alignment and setup along with cable layout, connecting the spindle motors VFD (variable Frequency Drive) Power Supply and then a real time actual machining test cutting a piece of timber. However It is not really practical to do this until I have the router setup on a bench with all it's associated components, computer, VFD etc. I also need to do this in the garage where the cutting dust coming of the machine won't mess up my clean workshop.
January 3rd, 2011
I have been performing some further calibration and testing. A few days ago I performed the process of TRAMMING the spindle. Not something that is absolutely necessary for this type of router but a worthwhile procedure to do anyway. TRAMMING is the process of squaring the spindle to the table.
Following this I wired up the VFD Power supply to the Spindle Motor and set it in motion. Now The router was really ready for its first fully functional CNC machining test. I created some G-Code to lightly engrave a centre mark and horizontal (X Axis) lines onto the router bed. These could prove handy in some situations setting up work on the bed.
January 8th, 2011
This is how the bench construction is going. I have been working on it for two days and despite the hot weather and having to drink lots of water everything is going very well.
Sunday 9th, Today I painted the bench with a spray antirust Epoxy Enamel. Even though this paint does take at least 24 hours to dry it is ideal for work benches as it sets very hard, almost like powder coating. I also prepared and sprayed the shelf. About to fit the wheels and shelf and then it will be ready to start mounting the router etc... I am almost starting to get a felling of, "what am I going to do next" once this project is finished.
Today have I added the final photo of the bench ready for mounting the Router. Just before doing so I fitted the keyboard slideout draw.
A few days ago I received and have now fitted a more sanctified flexible Stepper Motor Coupling. You can see the significant difference between the original (last photo) and this newer one. The original was OK but I wanted something more robust and of higher quality. The mounting is now different in that I made the central tube from clear Perspex and I now have aluminium spacers on the four mounting screws. I could not just use the original aluminium cylinders as they were too short for the longer couplings the shaft clamp screws were located differently. I chose Perspex simply because I had some on hand and being able to see through it to the couplings looks kinda cool.
January 12, 2011
moved the router from its construction table to the bench. In addition mounted the monitor, VFD Power Supply, Computer, and acrylic sheets to the left and under the router. The acrylic sheet under the router is easily removable from the front to allow oiling the Y axis lead screw. I had some issues with the new Y axis flexible coupling so have since taking these photos temporarily reverted back to the original. I still have to tidy up the cabling but all things being as they are this project is almost complete. Soon will come an actual test, however it all looks so clean and nice I am reluctant to get it all messy.
January 13th, 2011
These taken today, I would regard as the final assembly photos.
I sorted out the cable routing and ran a full dynamic operational test without actually cutting anything. In the next few days I will take some video of it in motion just prior to setting up for an actual cutting test. Not sure what this will be at the moment but likely it will be a combination of patterns and text. Something simple at the start like a big circle.
January 15th 2011
Started work on designing new Gantry Side Supports.
The router as it is currently has straight Gantry side supports. The disadvantage of these is that I loose over 100mm of bed routing length in the Y Axis. Now that I have the router completed I can use it to profile and machine offset Gantry sides that will place the spindle motor further back towards the centre of the Gantry thus giving me back that 100mm Y machining length. See video clip on the home page using the router to pen plot the basic layout. Doing a pen plot allowed me to verify my design and all the dimensioning so that all the mounting holes for the linear bearings and stepper motor match the existing sides. Good thing I did this as my first CAD drawing had a few dimensional errors. This is going to be a very long time consuming routing job, profiling this size aluminium to a depth of 12mm. I am going to use a 5mm 2F End Mill taking it very easy 0.5mm depth of cut for each pass. It will take a good hour or more just for the outside profile. First I will experiment with a small profile on a piece of scrap aluminium just to see how the router handles it. After all... my main intention is to use this router for wood projects, machining this size piece of aluminium will be a real test of its rigidity. YouTube Link to Video.
Page Last Updated March 26, 2016
January 30th 2011
I fitted clear acrylic side shields around the cutting table to help reduce chips flying all over landing on the floor. If you look at the photos you can see that it seeme to work fairly well.
These are all the photos I took machining and fitting the new off-set gantry sides.
I havent spent time putting much in the way of comments for each photo as they are fairly self explanitory.
The finished router.
January 31st 2011
Posted video shot while routing the new off-set Gantry Side supports. See this on the HOME page and the CNC Router Video page.
This video is also now on YouTube.
From now I will only be updating this page to correct any errors along with any significant improvements or additional information.
I hope that what I have created and the information provided might be of some assistance in designing and building your own CNC Router.
There are countless ideas, designs and configurations publicly available out there on the web and YouTube. Making ones own CNC Router is extremely popular these days. Before embarking on this project I spent weeks researching both commercial designs and home built ones along with making countless sketches. One thing I found was that the basics always remained the same "XYZ". It was just a matter of my own personal experience along with the machines and tools I had at hand in my workshop that determined my specific design, as you see above. I learnt a lot making this CNC Router and if I decide to make another one, yes, I would do some things differently but for the most of it I would stick with the same design approach. However now I have this machine I could use it to make some of the components for the next one a lot more accurately. However I don't see this happening in the near future as after all I need to use this one a bit first. So for my final comment, all I can say is that, when I started this project all those months ago with some uncertainty and trepidation, to see it all work now, the results have been the most fulfilling and satisfying one could imagine.
COMPLETED February 2011
February 4th 2011
Added a further modification to make the X-Y 90deg adjustment easier by the use of supporting U fixtures that allowed the use of grub screws to make slight movements of the lower X axis linear rail forward and back. Previously I did this by just holding it up with my free hand, moving it and then tightening the end securing cap screws. With this new method I can get more precise control. It is surprising how little movement is required to effect the preciseness of a 90deg cut. It only needs less than 0.5mm or so, enough moment in the support cap screw slots being 6mm wide with a 5mm cap screw thread. For just general wood and the like routing as it was would have be quite adequate, but as I am a bit of a perfectionist I had to make it just that more precise. After all I know I can use it for aluminium machining and routing as well if needed. I have included comments in the images below that should cover most of the explanation in relation to this modification.
DOWNLOADS Updated - Additional information and content.
I regularly receive inquiries asking for construction drawings and dxf files for the router. Unfortunately I simply don't have any more than what is available on this page. If in the future, if I do create more detailed drawings etc, I will post them. However I don't envisage doing this in the near future. I would love to help everyone but unfortunately at the moment this is not possible. For now, I do hope you find what I have published of use in creating your own CNC Router.
The updated and new downloads below may be of some further assistance.
To download the Q&A, Right Click the link and select Save Target As.. The other files are ziped.
UPDATED March 26 2016
NEW March 26 2016
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