My CNC Building Adventure

[JayneV]

Hi everybody,

I decided to build a CNC Router for my next project. @John Nicholas gave me inspiration with his awesome CNC build and......well........ it's just a really cool toy to have in the garage.

My machine will be based on one built by JermNZ over at CNCZone. This is a link to his build thread and his website if anyone is interested in seeing a finished version of the machine:
https://www.cnczone.com/forums/momus...ml#post1549298
https://jeremyyoungdesign.com/category/diy-cnc-router/

With so many different designs for diy CNC Routers all over the internet, each with its own pros and cons, it wasn't an easy decision to decide which one to build. In the end, I settled on this design because I already have most of the materials for the frame construction and the design seems like it will work well for what I want.

The machine will be used for various woodworking projects, especially making more stringed instruments. I have partially designed an electric bouzouki which will hopefully be my first big project. I am also hoping it will have the ability to experiment with some aluminium work. I don't have any specific projects in mind for aluminium, that will be mostly experimenting to test the limits of the machine and to learn some new skills.

I have made some small modifications to the original design. The attached images show where the design is currently at. The biggest change I have made so far is adding a cutout into the front part of the bed to allow parts to be machined on their edge. I got the idea for the cutout from @Mac.CNC in his Momus CNC build thread here: https://www.cnczone.com/forums/momus...ml#post1385334

Here are some images to show where the design is currently at. I haven't yet started the build because there is no space in my garage yet. I'm in the process of rearranging and cleaning out the garage to clear a space for the machine. I will start with the bench which will be more or less the same as what is shown in the CAD images below and then move to the actual machine construction. I'm very excited to be taking on this project.

Hope you enjoy follow along and I welcome all feedback, good or bad as it is kept respectful.

 

[Jim_in_PA]

I look forward to your build!!

 

[John Nicholas]

This is going to be epic! After watching your Purple 4 string build, this project looks to be evn more interesting. Your attention to detail will be inspirational when following along with your CNC build!

I'm here to cheer you on along the way!!

 

[tomasz]

Looks awesome! i'll be watching

 

[JayneV]

I look forward to your build!!

Hi Jim, Thank you.

This is going to be epic! After watching your Purple 4 string build, this project looks to be evn more interesting. Your attention to detail will be inspirational when following along with your CNC build!

I'm here to cheer you on along the way!!

Hey John,
Thank you for your too kind words. I'm sure there will come a point where I will need some cheering along, so feel free do so, it will be much appreciated.

Looks awesome! i'll be watching

Thank you. It will be a long build, so get comfortable. I will try to keep this thread as interesting as possible.


I made some good progress today with making space in the garage for the CNC build. There was some heavy pallet rack shelving units in the garage that needed to be moved into the shed. I can't believe how much stuff (crap!) get accumulated over the years. With those shelves now in their new home, I can started filling them with all the stuff in the garage that doesn't get used much and set aside a pile for the stuff that belongs in the garbage to go out with the next council clean up day. Unfortunately relocating things to the shed and cleaning up the garage is taking longer than I had hoped, so the CNC build won't start until sometime next week. Moving those very heavy shelves has worn me out and now I need to rest for a day or two.

 

[ghostchord]

Cool project. I built a small CNC machine about 10 years ago, it's sitting right by me... didn't get too much use for various reasons...

Did you do all this CAD work? Looks very professional.

I see you plan to use linear rails which is great. It's hard to see but you'll want each axis supported by four carriages.

What is the planned working area? Looks like you won't be able to get the tool all the way to the far side of the bed, something to think about. I think spending some time thinking about the kind of things you'll want to CNC and what sort of working area you need for those is worthwhile early on. Don't repeat my mistakes

Thinking about the enclosure early on is also a good idea. I had a tool fly out of mine, no enclosure, missed me ('cause I stood a safe distance). Dust extraction is another important thing and an enclosure helps there as well.

When I look at the design I'm sort of doubtful it will work with metals. You generally need a much more rigid machine for that. This design looks weak in the left to right direction (those supporting plates will deflect) and generally doesn't look super stiff in all directions. Metals also generally want coolant to help cutting. To some degree just taking lighter cuts help get you somewhere but might not end up that great.

Are you planning to use stepper motors? I got some I want to get rid of...

All in all looks like a nice little machine. Are you going to buy this as a kit or make/buy parts yourself?

It sounds like you have some relevant experience here if you already have some of the materials...

One of these days I might go back and build machine #2, or at least upgrade #1... I do have a build thread on CNC Zone for this old one. Gonna follow this build as well!

EDIT: https://www.cnczone.com/forums/diy-cnc-router-table-machines/62620-cnc.html ... hmm more than 10 years ago...

 

[JayneV]

Hi @ghostchord. I purchased CAD model of the machine from Jeremy (goes by JermNZ at CNCZone, links to his build thread and website are in my opening post). I made some changes to his model, mainly adding the pocket in the bed and slightly adjusting the size of the working area, which is about X-750mm, Y-900mm, Z-180mm. The bench and enclosure are drawn by me with Fusion 360.

You are right, the far end of the bed is not reachable by the tool. The bed doesn't need to extend all the way to the back of the machine but it looks neater that way. 750mm is more than enough for the X axis and 900mm for the Y is also enough but I may extend it slightly if space permits. I won't know exactly how much space will be available in the garage for the CNC until I've finished cleaning and rearranging things in there.

Yes, the rails are all flat linear rails and there are 4 carriages per axis, although it is not very clear in the images.

YIKES! You had a tool flying out of your machine? That would have been really scary, good thing you were safely far enough away. An enclosure makes sense in many ways.

I would only think about cutting soft metals like aluminium with this machine, but that won't be its primary purpose. Aluminium work will be more for experimenting and if it turns out not handle it well I won't be too disappointed. If the experiments prove successful, then I will add a coolant system. Time will tell how well the metal experiments work.

Yes, I am planning to use Nema23 3Nm stepper motors. Servo motors would be nice but way out of my budget. There is no kit for this machine. The base framework will be welded steel which I already have and the gantry will be made from aluminium 20mm plate and 90x45 t-slot extrusion. I'm not sure how to cut the plate yet. My brother owns a small machine shop so my first preference is to use his machines to cut and drill the plates but we are in lockdown here and may continue to be in lockdown until Christmas so depending how far along the build is by the time I need those pieces, my brother's shop may not be an option. Second option is to send drawings to a local laser cutting place, have them cut the parts and then deliver them to my house. I have no idea how much that would cost though, so the cost may dismiss that option. And the final and least favourable option (by a long way) is for me to cut the plate by hand.

This is my first CNC build and it will be a challenge to maintain precision throughout the construction process to ensure the finished machine is accurate.

Thanks for the link to your build thread at CNCZone. I've added it to my list of things to read.

 

[ghostchord]

Having access to a machine shop will probably make this much easier. I had access to one when I built mine. It was sort of the motivation, I had a lot of scrap material (being able to grab anything from the scrap bin of a big machine manufacturer helps) so I spent very little $. As a software person I was just trying to learn some stuff (some machine design, CAD and some hands-on experience) and have some fun, didn't really have anything concrete in mind as to the use of the machine some vague ideas about getting my daughters into robotics (didn't work ) I wasn't into guitars yet back then. There's some interesting design elements in mine but definitely don't copy anything blindly

Are your aluminum plates milled flat? If not you'll probably want to do that. Manufactures of ball screws and linear rails typically have information about how to use them in applications. Linear rails for example need to be put on a flat surface and their assembly process requires the bolts be torqued in some specific sequence while ensuring the rail is straight. I'm sure a lot of hobbyists that just do wood don't really bother at some point but if you're already tinkering it might be more interesting to learn a little more about precision machines...

Have fun! Post photos!

 

[JayneV]

I'm not holding my breath about having access to my brother's machine shop anytime soon. Like you, this project is about learning something new and having fun. Robotics sounds very interesting, did you ever make anything?

I haven't purchased any aluminium yet. If I can get access to my brother's shop, then I will definitely be creating flat milled surfaces wherever necessary otherwise it will depend on the cost. I downloaded information booklets from the Hiwin website. They have loads of good information which would also be useful for other brands of similar products.

Pictures will be coming soon when the build commences. I'm already having lots of fun with the design stage, and the great feedback already received in this thread and at CNCZone. I can't wait to start turning the CAD model into reality. I just realised I didn't mention my primary build thread at CNCZone in the opening post. Since that forum is all about CNC machines, I figured that is the best place to look for advice and help along the way. The intention for this thread was to be a condensed version of the build since it is a guitar forum. My machine will be used to build guitars and other stringed instruments I dream up. I am happy to include more or less information in this thread based on what you all want to read here, let me know. For anyone interested, this is the link to my build thread at CNCZone:
https://www.cnczone.com/forums/diy-cnc-router-table-machines/424022-cnc-forum.html

Jayne

 

[JayneV]

Spent another day cleaning the garage. It’s amazing how much junk gets accumulated. Good news is I have found the space where the CNC will live and that area is is almost cleared. For a CNC build thread I am spending an awful lot of time talking about cleaning out sheds and garages. I promise the build will commence soon, it’s just taking a little longer than expected. I thought it would be better to do a thorough spring clean and get rid of all the crap taking up space that never gets used instead of shoving it all into a dark corner of the shed.

So while doing all this mundane clean up, my mind is running around thinking about the CNC. The way the Y axis (long side) is set up has been bugging me. I like machines that have tall side walls so the linear rails are up high and away from most of the flying debris from the cutting tool. Also, having the rails up high eliminates the upright supports of the gantry. I feel this all adds up to making a more rigid machine which would have a better result working with aluminium.

Of course making these changes involves a major redesign of the machine. Here are some CAD images of what I’ve come up with for the frame.



These are preliminary drawings as a proof of concept to see if I can make it all work. Next I will work on modifying the gantry to suit the new base.

 

[guitarbuilder]

My K2 machine has the rails below the table on the sides. The table actually covers them and those don't seem to be bothered by chips. My X carve has the belts up high and chips are a problem there. Even on my first homebuilt, my linear rails were low and not a problem. This is not mine, but off the net.

 

[JayneV]

The K2 has an interesting arrangement for the gantry upright supports. From the photo, it looks like they would flex under heavy load. What type of materials do you cut with it?

The main reason I want to raise the sides up is to increase overall rigidity because I'd like machine aluminium.

 

[guitarbuilder]

The K2 has an interesting arrangement for the gantry upright supports. From the photo, it looks like they would flex under heavy load. What type of materials do you cut with it?

The main reason I want to raise the sides up is to increase overall rigidity because I'd like machine aluminium.

Strictly wood, but my machine is built a bit differently. I'll try and dig up a picture.

Here is a smaller version of mine. You can see parts are a bit more solid.

 

[Jim_in_PA]

This is a much larger machine than you're building, but for reference, the linear rails for the Y axis are on the underside of the machine frame along the sides below the rack and pinion. You can just barely make them out in the photo. (the grease zerks are fun on those for maintenance!)

 

[JayneV]

Strictly wood, but my machine is built a bit differently. I'll try and dig up a picture.

Here is a smaller version of mine. You can see parts are a bit more solid.


View attachment 899144

Oh ok, yes, that does look more solid than the previous image.

This is a much larger machine than you're building, but for reference, the linear rails for the Y axis are on the underside of the machine frame along the sides below the rack and pinion. You can just barely make them out in the photo. (the grease zerks are fun on those for maintenance!)

Jim, that is a very nice looking machine, and HUGE! It looks big enough to take a whole 8'x4' sheet? The location of the linear rails underneath on this design is very neat and tidy and keeps them out of harms way.

 

[Jim_in_PA]

No, not a 4x8...that's a 4x4...49"x50" to be exact. I wish I would have purchased the 4x8 version, but space was at a premium and I got cold feet on that. In hindsight...well...you know...

 

[JayneV]

Hi everyone,

Sorry for the slow progress to get started on this build. I haven’t had a chance to do much work in the garage since last Wednesday. However, the evenings have been busily spent working on the revised machine design in CAD. I abandoned the idea of trying to make do with the steel hollow sections I’ve already got, leftover from a previous project, in favour of using aluminium flat bar and plate. I’m happy with the way the design is now heading. The gantry beam still needs some work to replace the heavy steel section with something lighter but still rigid enough for what I want.


Jayne

 

[JayneV]

Hi everyone,

Since making the decision to modify the CNC design I purchased, things have been moving at a slow pace. What I originally thought would be a few changes here and there ended up turning into a complete redesign of the entire machine.

The gantry beam is now a built up aluminium box section made from two flat plates and two C-channels.

This evening I found a solution to the part giving me the most trouble, the saddle assembly. Compromises need to be made between function, compactness and rigidly when designing a saddle to travel in the X axis and carry the Z axis. After many iterations I have settled on a saddle design and narrowed the gantry beam down to two configurations. Both beams are basically the same, the only difference being the way one of the C-channels is installed.

This beam has the front C-channel installed with the open part of the “C” facing outwards, creating a “trench” for the X-axis ballscrew to sit in.


and this beam has both C-channels installed with the open part of the “C” facing inwards with the screw mounted on top of the beam.


The second beam may have a bit more rigidly than the other one so is currently my preferred choice. I’ll think about it for a day or two before deciding. Then it will be a matter of double checking all the components in the model for any errors and generating 2D drawings. Some of the aluminium parts I’ll have laser or water jet cut if the price is reasonable to help maintain tight tolerances during assembly. If my brother’s CNC mill has enough down time between his customers orders, that would be an even better option to manufacture the parts.

Hopefully one day soon I can start posting photos of the actual machine construction instead of CAD drawings.

Jayne

 

[John Nicholas]

Jayne,

I prefer the second design for a number of reasons, but the most important is moving the ball screw away from debris caused by the Spindle.

You are doing all the correct steps in ensuring that you design fits into what you want. I wish I had a tenth of your skill in using CAD. Me? I still use a paper and pencil and don't always get that right!

Personally, I can't wait to see you begin your build. It's going to be out of this world!

 

[JayneV]

Jayne,

I prefer the second design for a number of reasons, but the most important is moving the ball screw away from debris caused by the Spindle.

You are doing all the correct steps in ensuring that you design fits into what you want. I wish I had a tenth of your skill in using CAD. Me? I still use a paper and pencil and don't always get that right!

Personally, I can't wait to see you begin your build. It's going to be out of this world!

I didn’t consider debris in either of the designs. The bottom face of the gantry is a little over 200mm above from the bed (I don’t remember the exact dimension). It’s unlikely that chips would fly directly from the cutter vertically up to where the screw is but airborne dust would probably make its way into that area and it would be more difficult to keep clean with all the protruding bolts and the screw in the way. That is a mark in the “against” column for that design and a mark in the “for” column for the screw mounted on top.

Thank you for the CAD compliment. I’m self taught with endless hours playing with a few different CAD packages over the years. It’s my OCD wanting a model to be as accurate as possible to the smallest detail. You have no idea how tempted I am to model every nut and bolt so that the model is a perfect representation of what the real life machine will be, but thankfully I have so far been able to resist going down that pointless path.

Paper and pencil has its benefits. The model with the screw on top of the gantry is version 9 of the machine and within each version there are about 10 saved sub versions plus countless other versions I didn’t bother saving. There is no way I would have made that many drawings with pencil and paper and chances are the machine would already be under construction by now.