low cost diy cnc router - content.instructables.com

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Low Cost DIY CNC Router

by Steve Tyng

UPDATE: UPDATE: What is good is getting better. Here's the next installment on this router: Click Here

_____________________

This is a hobby CNC router I built for myself that I'd thought I'd share with the Instructables community. This is not adetailed build log of the router but more of an exploration of my design choices that went into this somewhat uniquetool. There are no plans for this router. Beyond a couple of initial sketches to determine general size, lengths, andspacing, this router pretty much grew out organically as I was building it. Hopefully other CNC enthusiasts may see anidea or two that might help them with their projects.

Design parameters

Use as much stu that I had laying around the shop as possible.Able to use the router as a bench top when not routing.A cutting area of 30"x60"x2".Make it as rigid as possible (for a plywood design).

As to the design I came up with. This is a classic XYZ 3-axis wood cutting router. By classic I mean it has a gantry thatmoves along the length of the machine base (Y axis). There is a carriage that the router is mounted to that runs back andforth on the gantry (X axis). And nally, there is a mechanism that raises and lowers the entire gantry that moves therouter up and down (Z axis). Yes, I said the entire gantry moves up and down. We'll be getting into that later. As tomotion, I'm using stepper motors and roller chain. For the linear rails, I'm using steel v-bearings running over steel angleiron. The primary construction material is plywood.

Lets get to the picture show.

Low Cost DIY CNC Router:

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http://www.instructables.com/Low-Cost-DIY-CNC-Router/

http://www.instructables.com/member/Steve+Tyng/

https://www.instructables.com/Low-Cost-CNC-Router-Part-Deux/

Step 1: The Base

Every tool needs a good base. Instead of building from scratch I re-purposed an Ikea cabinet I had available. The cabinetwas completely disassembled and then put back together using adhesive at every junction. I reinforced the cabinet bymelding in a 2x6 substructure on the bottom. Casters and levelers where added for mobility. Finally, I used a commercialsolid core door for a bench top. Not shown, but the door was shimmed so it would lay as at and true as I could make it.The door will be the actual base for the router.

Why a solid core door for the machine base? For one, I had it available. I use these doors as bench tops in my shop.Secondly, commercial solid core doors are built to be as at and true as possible. And third, their heavy as hell and Ithought all that mass would be advantageous in soaking up vibrations from the router.


Step 2: Linear Rails

Linear rails for CNC seem to be a dime a dozen nowadays on eBay and Alibaba, but in 6' lengths? Not so cheap. What ischeap is 1" angle iron at my local home center. Something else that's cheap (at least cheaper than they used to be) are3/8" ID steel v-bearings. Combine the two, and we get the linear rail system I'm using in this build. Pictured here are my

rst tests using angle iron and the v-bearings. Seemed to work well so I cut the 45 degree plywood rail beds on thetablesaw and mounted the angles to the underside of the router base. Not well pictured, but tensioning of the v-bearings onto the angle is accomplished by a bolt and dowel-nut setup. Those slits between the v-bearings allow forenough movement for the tensioning.

Something you may have noticed are the plywood strips attached to the edge of the door/router table. There's nothingsigni cant about these. After I cut the door to size I decided I wanted to increase the X travel to a full 30" which requiredwidening the table.

Why mount the Y rails under the table? This left the top clear so the entire surface could be used for cutting. It also allowsme to use the router as a work/assembly bench when I'm not routing.

Notice how far apart the the pairs of Y axis v-bearings are apart on the bottom of the gantry side plate? I did this tomount the gantry plates as rigidly as possibly. This made the plates longer which required more table length to get methe 60" of Y travel that I wanted.

Sorry to say but this is about it for historical photos of this build. The pics that follow were all taken after the router waspretty much complete and operational.


https://www.vxb.com/RM2-2RS-3-8-V-Groove-Guide-Bearing-Sealed-p/kit8405.htm

Step 3: Gantry and Carriage Details

UPDATE:UPDATE: I've dumped the ying gantry design of this router. Moving the entire gantry up and down for the z-axismotion worked ok but it had issues. Mainly that it was very slow. It could also occasionally go out of alignment if one sideskipped steps. The router has been rebuilt with a new setup where I moved the z-axis mechanics to a new router carriage.You can check that out at part two of this build series.

The gantry is built from two layers of 3/4" ply glued together. Along the top and bottom, 45 degree recesses were cut and3/4" angle irons where bonded into them using Gorilla glue. The entire gantry moves up and down for the Z axismotions. To accomplish this, the gantry has a length of 1" angle iron in the vertical orientation that sit in v-bearingsattached to the gantry side plates. The up and down power is supplied by a NEMA 23 stepper and screw assembly oneach end.

Notice the gantry overhangs? The gantry beam is mounted in front of and extends past the side support plates. Thisallows the router carriage to slide past the side supports (more on the right than on the left btw). You don't see this muchon DIY routers for some reason. This setup allows the router to cut from edge to edge a full 30" in the X axis.

The router carriage is glued up from two layers of 1/2" cabinet grade plywood, much the same way as the gantry sideplates. Since I have that overhanging gantry, I was able to make the router carriage longer (spreading the v-bearingsfurther apart) which increases rigidity in the X axis. The Makita router is mounted on the left side of the carriage. Thisopened up area for the dust collection system to the right of the router. The carriage has four of the v-bearings that runon the top and bottom angles on the gantry. Tensioning is done the same way as on the gantry side plates.

Flying gantry? To provide the Z axis motion the entire gantry moves up and down. On most CNC routers the gantry isxed and the Z axis motion is all done at the router carriage. I'm moving the entire gantry for a few reasons. First, my

thinking is that if I moved the Z axis mechanics out to the ends placing them between the gantry and the gantry side


https://www.instructables.com/Low-Cost-CNC-Router-Part-Deux/

plates, I could spread the loads out and increase rigidity. Secondly, removing all the Z axis mechanics and motor from therouter carriage, greatly simpli ed wiring going to the carriage. Third, I gured why not? It works in 3D printers and as itturns out, is working quite well with this router. Besides, it looks cool when the entire gantry moves up and down.

Z motor mounting. What may not be obvious is how I have the two Z motors attached and mounted to the jack screws.In a typical setup, these motors would be hard mounted to a base. The screws would be mounted in a bearing assembly.To connect the two would be a exible coupling. I avoided all that complexity by hard mounting the motors to the screwshafts. The only thing holding those motors in place are the 1/4" shafts stuck into the 1/4" holes I drilled into the screwshaft ends on my mini-lathe. The motors are kept from spinning by the wood bracket with that rubber bushing on theend (which allows the motor to wobble if it has to). This may seem an odd way of doing this but this method eliminatesthe exible coupling and ddling with alignment. The 1/4" shafts of the stepper motors are more than strong enough tokeep the motors in place.

For X and Y axis motion, the carriage has one NEMA 23 240oz (torque) stepper mounted. The Y axis motion is powered bya single 425oz stepper that is driving a shaft that is attached to both ends of the gantry. Mechanically, it would have beeneasier to go with two steppers for the Y axis but I only had one motor available at the time and I had the shafting andbearings to fabricate the drive. One nice thing with this setup is that the gantry will never go out of alignment due to amotor skipping.

A chain reduction on the axis drives? I rst built this with the stepper's driving the chains directly. In the initial testing, Iwas getting a lot of skipping in the (weak) motors I was using at the time. I had the sprockets and bearings available so Iadded the reductions. Besides adding a ton or torque, they de nitely helped in the precision category (more on thatlater).


Step 4: Roller Chain?

Yep, I used 25P roller chain in this build. I didn't use timing belts, ballscrews, or rack and pinion. If you don't know, rollerchain has a bad rap in the DIY CNC community. Arguments against are that it stretches, it's not very accurate, and itcaused the fall of the Roman Empire! Anyhow, I didn't know all that when I started this build and I had a bunch of thechain left over from another project. I'm enough of an engineer to know that roller chain could have issues but I hadsome ideas on how to mitigate those. Before I started this build I'd studied other chain driven designs and always noticedone thing. These other chain designs always seemed to have the chain hanging out in mid-air, unsupported, with somesort of imsy looking tensioning system on the ends. Roller chain has some weight to it, even #25 chain. What willhappen if 5' of it suspended horizontally in mid air? It will droop and no matter how tight you tension it, it will still droopto some degree. What that droop on a linear motion system means is that you will not get consistent movement alongit's length. What I did with this design is that the chains are supported along their entire lengths. The X axis chain sits inthe bottom of the top angle of the gantry. The Y axis chains lay in a cutout in the Y angle supports. There's no drooping inthese chains! To secure the ends of the chains, I used 3mm hex wrenches which t quite nicely in the #25 chain.Tensioning is handled by exible sections of ply on one end of each of the chains. A tensioning screw runs though a t-nutwhich bends the ply tensionor out and pulling the chain taught.

Note that the chain mounting and tensionors sit right on the angle iron ends. This setup uses the angles in compressionto add to the rigidity of the chain mounting.

What's that coupling looking thing in the rst pic? That's a compression coupling that joins the left and right Y axissprocket drives. Loosening this up allows me to precisely adjust the gantry perpendicular to the Y axis travel.


Step 5: Router and Dust Collection

The router is the Makita RT0701C 1/4" trim router (earlier pics show a cheap Harbor Freight router which has since beenchucked). The router has turned out to be precise and it has a nice speed adjustment built into it.

Dust collection. I have a small basement shop and I wanted good dust collection on this machine. One wrinkle with thisdesign is that since the router carriage moves up and down with the gantry, I had to come up with a design that keepsthe dust shoe on the work piece. This was accomplished by mounting the dust shoe on an arm that allows it to freelymove up and down in relation to the gantry. Three plastic v-bearings were used as shown in the pic. The one bearing isattached to the movable arm that allows for a quick and easy removal of the dust shoe from the machine. The dust shoewas machined ( rst thing I cut on this router) out of two pieces of 1/2" plywood. The bottom pad was cut out of apainting pad and allows the shoe to oat over any screws or bumps in the work piece.

The dust cyclone is mounted on top of a standard 5 gallon bucket and keeps most (if not all) the dust out of the 8 gallonshopvac that I'm using.

This setup has proven very good at sucking the dust and chips up. After a cut, there's hardly any dust left on the workpiece or oating around the shop.


https://www.amazon.com/Makita-RT0701C-1-1-Compact-Router/dp/B00E7D3V4S/ref=sxin_2_ac_d_rm?ac_md=0-0-bWFraXRhIHJ0MDcwMWM%253D-ac_d_rm&keywords=Makita+RT0701C&pd_rd_i=B00E7D3V4S&pd_rd_r=a66b8669-6210-4a23-9b2a-2d7736a4b996&pd_rd_w=Yr6FP&pd_rd_wg=A4PDD&pf_rd_p=ed481207-4bea-4e19-bbad-73ed40fdc292&pf_rd_r=PWJAV3342QECZCQVZWBC&psc=1&qid=1573033803

Step 6: Controls and Wiring

Not many pics on this one I'm sorry to say. The control system is Arduino UNO based and I'm running the EstlCAM CNCsoftware (which is awesome IMO). On the wall is a little Windows 10 media PC that is running the Windows side of theEstlCAM system. A wireless keyboard, mouse, and a game-pad nish the controls out.

On the back of the machine inside the black box in the center is an Arduino Uno which is running the Estlcam controllersoftware. In the electrical box is a 10A SSR (solid state relay) which switches the router on and o . To the left on a shockmounted base are the TB6600 stepper drivers. The power supply is a 24V 15A fanless design.

No whirlygigs! I made an e ort to use fanless passively cooled equipment for all my electronics. This is so no dust getssucked into anyplace it shouldn't be. I also kept an eye on mounting orientation. The stepper drivers are mounted soheated air will naturally ow upward. The Arduino case has holes drilled into the top and bottom for the same reason.

The wiring to the motors is running through the exible black cable protectors picked up at a computer store. The motorcabling is four conductor trailer wire .

Noticed that articulated cable support going to the router carriage? A couple pieces of plywood and some hinges, and aquick and easy cabling solution to the carriage is the result. Works quite well.


https://www.microcenter.com/product/486544/inland-uno-r3-mainboard

http://www.estlcam.de/

https://www.amazon.com/Fanless-Desktop-Computer-x5-Z8350-Processor/dp/B07F1MM92S/ref=sr_1_9?keywords=acepc&qid=1573034070&sr=8-9

https://www.amazon.com/s?k=TB6600+stepper+driver&ref=nb_sb_noss_2

https://www.amazon.com/gp/product/B077XDC487/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1

https://www.lowes.com/pd/Reese-24-ft-4-Way-Connector/50437628

Step 7: Does It Cut?

Of course it does!

There's been issues of course and It's a continuing learning curve. I've been experimenting with materials, cut depths,and feed rates to see what the router can do.

Currently, for cutting plywood and MDF, I've been running around 70IPM (inch per minute) speeds on a .25 bit with a .28cut depth. The Z axis is currently set to 20IPM.

Free travel speed is set to 140IPM with no issues.


Step 8: Is It Accurate?

https://youtu.be/wD5KRtZmsnQ

https://youtu.be/LXfWWEwZMZc

How's .005" repeat-ability sound? That's 0.127mm for you metric types. Yeah, I know. That sounds to good to be true witha DIY roller chain driven plywood router but that's what I've seen in some of my testing. I'm not saying .005" accuracy willcome out of this machine with every cut but at even four times worse, it's a lot more accuracy than I was ever expecting.

So why so accurate? Who knows? Maybe I'm an uber machine designer and fabricator. Maybe that reduction on themotors had something to do with it? Maybe the stars were in alignment? All I know is I'm very happy with it. Not toshabby for a machine that might have $900 of material in it.

Hope you enjoyed this write up. I'll add content as I think of it and I look forward to any comments or suggestions.

Thanks for reading.

Steve


You are some smart fella.

Very elegant design. I love it!

It's getting more elegant with each rebuild!

I'm just a garage DIY guy, but I am incredibly impressed. You have every right to be proud of yourwork.Maybe it's the frustrated editor in me, but I believe it should be "too good to be true" and "not tooshabby." Anyway, wow! What an accomplishment you've made.

Step 9: Accesories

First thing you learn when you get your CNC router up and running, is that you immediately want to start improving it.My rst project along these lines was a touchplate for automatic zeroing. These are usually made from milled aluminumbut I gured some plywood and some aluminum tape and strips would work. It did!

https://youtu.be/K8jZ33agu9w


Thanks dude!

Great work I have built 9 table for both routing and plasma cutting, I use similar setups for thedrive assemblies but in different configuration. Do create a plans package I have sold over 500sets world wide, it will give you extra cash for other related projects. I agree with Estlcam I haveused it for doing plaques and other projects. You can add optional attachments to expand yourtable use. Like a drag knife for sign vinyl cutting, diamond scribe holder for metal etching. I wouldadd an overhead boom for the Vac hose and router power.https://youtu.be/-C48ROJ-5KQhttps://youtu.be/0oiemc9ZUfghttps://www.youtube.com/watch?v=gn1Xh9PaInc&feature=youtu.be

Have funTom

I'll need to take a closer look at your drag knife if/when I decide to get into vinyl cutting. On theplans set, I'm slowly working on it. On the dust collection, I'm playing around with differentconfigurations.

Nice effort trying to promote yourself, "acourtjester" / "Big Irish" / "Tom".

As of now - 26 Nov 2020 - you have gotten these results on Youtube:

Your video uploaded 2 Jan 2019 - 3 likes.Your video uploaded 14 Nov 2018 - 5 likes.Your video uploaded 29 Mars 2018 - 7 likes.

You say: "I have sold over 500 sets world wide".The numbers speak against that claim. Clearly.When you click "About" regarding your account on Youtube it is - blank.

Maybe you are sincere - but IF you want to at least SEEM like it - you should improve on a lot ofthings.

The first thing should probably be - NOT trying to promote yourself in a comment regarding whatanother person has created and publishes as an Instructable of 'how-to-do'.

if I was self promoting I would have given a means to contact me, my sales were on eBay andother websites. I have stopped offering the plans about a year ago.Your info is the one that is incorrect, my post here was to encourage the poster and others whoread his post by showing other things that can be done with a CNC table. I also said to him docreate a plans set to offer to make them available for other to enjoy building their own table.

Very nice project, but have you considered the expansion of the wood caused by humidityvariations?


https://youtu.be/-C48ROJ-5KQ

https://youtu.be/0oiemc9ZUfg

https://www.youtube.com/watch?v=gn1Xh9PaInc&feature=youtu.be

Since I zero the router to the workpiece at the beginning of each cut, I figure dimensionalvariations due to humidity do not factor in. At any given time the machine is in a certain statedepending on temperature and humidity. Temp and humidity will not change much during a cut.This means the dimensions of the machine will be relatively stable during a cut. If this were aproduction machine that was homing to the same spot for every cut, machine stability would be abigger factor.

Wow!And Thank you - I have been thinking of a way to build a stock flattening table for cheap (since I'llseldom use it!) and your angle iron rails introduced me to a way to recycle some steel I've had inmy collection (free rails!) for years. And the Grooved Bearings (V and U, too) were another item Ihadn't thought of.PS Love your fully supported roller chain two! ;)". . . sounds to good to be true with a DIY roller chain . . ."

Exellent! That's why I posted this build. To hopefully give others ideas for their projects.

Spitzen Leistung.

Looking Forward to any updates! Are there additional details on another site??P

Simply Awesome. I admire your details!P

Great job, I'm working for years on mine, but I never finished it. This gave me the kick to restartmy project. Greetings from Luxemburg.

WOW! Impressive! Welcome to the Instructables family! Congrats on the Grand Prize!

Congrats on getting the grand prize. Well deserved!

This looks WONDERFUL. I'm forever on the lookout for a DIY CNC machine big enough to doguitar body blanks and necks without breaking the bank and pissing off the wife. I could actuallysee myself putting one of these together. Thank you for sharing!

Look at "Smokey CNC" on YouTube.He built a beast of a CNC with parts he bought off Amazon.

Thanks!

I was wondering, how much Z axis travel would you want for the guitar work?

would you share some information and photos of the Uno and the supporting drivers? I'm using aramps and not getting the accuracy you're seeing. All data is appreciated.

I have 12t sprockets on the drive chains which gives 3" travel for each revolution. Driving that is a3.555 to 1 reduction with microstepping set to 8 on the drivers. That equates to a .000527"resolution (I think) for each motor step. Probably explains the accuracy I'm seeing. How's yourmachine setup mechanically?

I'm using an Arduino mega (marlin firmware) with a Ramps board. These drive Nema 17 motorswith 16t sprockets and GT2 belts. For my Z, I'm using s T8 lead screw rod. I ran a part todaywhich should have been a 100mm square. I got 99.2mm on one edge and 99.35 on the other.


What electronics and firmware are you using?

I'm using an Arduini UNO and TB6600 drivers. I'm using the EstlCAM firmware.

What's your microstepping set to?

I feel certain I'm set with all three jumpers on the RAMPS so that would be 1/128th steps. I think Iwould like to explore your solution. Is there a link for the schematics, install, specs for the setupyou went with? I think the TB6600 are more robust and perhaps the better solution.

My setup is simular to this: https://kalaakaar.in/cnc-controller-with-arduino-tb6600-and-grbl/

To wire to the UNO I used one of these:https://www.amazon.com/gp/product/B07HF2DD7T/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

The cost saving features are very nice.Question about the chain slack.If it hangs in air the slack is visible.If it sits on a surface the slack is still there but without visible sag. The slack is still in the linkagesof each ring... is this correct?

Or, is there a very small gain because the few ounces force of gravity is not in play?

The chain is tensioned to remove as much slack as possible (like tightening a guitar string). Withthe chain supported it's always in a straight line so the amount of chain to travel to get from onepoint to another is always constant. If it droops, this introduces an arc to the chain. An arc is not astraight line from point A to B and the arc constantly changes depending where the gantry is. Tome this means you will not have a constant amount of chain to travel to get to any point. Ofcourse, were proably splitting hairs here between the two but I was able to support the cahin inmy design so I went with it.

Yes, we're splitting hairs as engineers do. Without the training I'm just speculating. I wonder if atest of repeatability, or a test of accuracy would show a difference?If I had a CNC I'd set the machine to move on a long traverse and see if it consistenty hits thesame pinpoint after a large number of cycles. Maybe just that, a pin point hitting a piece of glossypaper taped down over a soft surface.

such a great build thank you for sharing this project it's perfectly done sir Steve succes to you.

Thanks!

Great project and takes a lot more expertise than shown in the description etc.You must be reallypleased with the results. Makita make some lovely tools and the Japanese made ones areexceptionally high quality.The use of chains is no worse than any other transmission system and should last a long time.Don't you just love stepper motors? One of man's best inventions - builds your vehicle andrepairs your heart valves. A fine example of tools (hardware and software) making tools. Makershave never had it so good. CNC used to be the preserve of massive robotic arms on assemblylines or factory machines from the likes of Cincinnati.One minor IT issue. Opening in Internet Explorer comes up with text only, no images. Opening inFirefox, no problem

IE is EOL from Microsoft. It's becoming less compatible with websites every day. Most currentweb development is for the Chromium based browsers.

Brillant!Thanks a lot for sharing.


https://kalaakaar.in/cnc-controller-with-arduino-tb6600-and-grbl/

https://www.amazon.com/gp/product/B07HF2DD7T/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

Fine Business !Perfect idea for perfect calibration, thanks.Pol

That is a cool router. My son is wanting to make a cnc router/mill but I don't really have any placeto put it. We built a 4'x9' CNC Plasma table a couple of years ago. Learned a lot from building it.We discussed using an Arduino, but purchased a commercial control box.

Space is always at a premium in the shop. My first router project was a 4x5' monster that wasdesigned to fold up when not in use. Sadly I never finished that router. The shop (and the house itsat behind) was sold when I had to move to another area.

Really well done, and I agree, the roller chain design you came up with is really smart."Conventional wisdom" needs to be examined more often.

Thanks. The roller chain seems to working well so far. Hopefully it will hold up to years of usewithout to much fiddling required.

Who to say ... Just "Waouw" ... !!! I am deeply impressed by your idea... Congrat's ;)

Thanks!

Good job! Just one hint. What's CNC? I know but it's always nice to define acryonyms the firsttime you use them. And maybe give an example that people can relate to.

Stands for Computer Numerical Control. Basically, any machine that uses a computer to controlthe cut is considered a CNC machine.

What software are you using? I use a Mac computer.

I'm using EstlCAM.

Wow, I’m totally in awe of your skills! Awesome design and functionality

Thanks!

You sir are a genius. Wow!! I wood love to have your machine. What is the cost to build and can Iget blue prints for it. It would be great to have something like that to incorporate with my woodburning hobby.


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