Very Nice build. What most people do not realise is that there needs to be a table. That is maybe the first consideration before getting into the machine building part. In your case take into consideration that the Spindle motor is going to get HOT which means that the 3D printed part will become soft and therefore you will experiance Z movement on spindle. I would use aluminium clamps for the required spindle - they are freely available now days.
Explanation of making axis rigid starts about 15 min in. I would recommend adding bearings on both top and bottom to eliminate error if the cutter is pressing down.
dude should have had you teach me steel deflection in school... My engineering teacher could not explain it that easy. Well done. Also good luck on the build!
I know this is an old video now at the time I'm comenting however still worth a mention for anyone who might come accross this. Instead of turning the ballscrew which is a large mass, rotate the ballscrew nut and have a fixed screw. I think having something like hgr15 or 20 guide rails fixed directly to the side of the table would be worth while considering for something of this size also. Would simplify the build and eliminate the problem of that flex in the y axis.
@@WillE86 thanks for your comment Will and you are 100% correct. My current machine now has a rotating ball nut and full steel frame with HGR 20 linear rails 👍 this initial machine was great for learning on cheaply and I made quite a lot of money using it which justified the upgrade. I was able to reuse all the motors, ball screws, electronics and spindle so upgrading wasn’t very expensive, the hard part was finding a working design that I could 3d print the rotating ball screw components
Subscribed! I saw in the FB group you mentioned moving towards the PrintNC design. I'm so excited to see your future videos and thank you for sharing your journey!
Thanks Zack, im continue to work on my design for a 4ft x 8ft printNC as there is currently no standard design for the machine in that size. Once mine is finalised and built i will be sharing my designs for the Jumbo printNC with the discord community hoping to have them accepted as an official version for others to replicate
In the Y-axis long tubes, you can probably insert a vertical plate inside through the corners to give it more stiffness. Or even a round aluminum tube that is a tight fit but then there is that annoying weld seam inside the square tubing. I don't know how much that would improve the sagging. But your idea was great with rolling support.
I like your idea's, brilliant fixes. I would suggest once the machine is done, cnc all your plastic parts in aluminum. Even the x and y holders where the square beam is in changing those to steel or aluminum will do a huge difference in vibration and tensility. Other than that excellent build man.
Hi Jamie, thanks so much for this video series. I'm new at this and figuring out how to make my own machine. The little details you are going into are very very helpful in helping me to understand the practicalities of the project. Its making me much more confident to have a go myself. Cheers from Bristol! :-)
No worries Dave, I was quite intimidated going into this build as there is a lack of instructions but so far I’m actually finding it’s quite easy and doable 👍 I had a flash of inspiration to build it from watching sailor Pete’s video and decided I would get started. Let me know if you have any questions about anything I’m happy to help 👍
Where you have supported the rail with your additional bearings: Its a great idea; but the cutting forces will be 180 degrees to the forces those bearings are loaded in. I would consider replacing the mild steel strip with an L section and having bearings above and below. That way it'll support the axis in both dierctions on the Z.
nice work dude, it looks like it'll be a very capable machine for the money. very creative fixes for the rail and ballscrew supports. i didn't quite understand whether you're using both solutions or decided to do away with the bearings on the flat bar. although its deffinitely very good, the trouble with that idea is that its only ever supporting at the gantry, so when you're at either end that 1mm sag under from the beams' own weight will do work on the 3d printed box tube holders, which will probably crack or deform fairly soon. not only is it putting downward force on them over a large lever, its actually being flexed up and down every time you travel past the middle. the idea i imagined before you showed your solution in detail is to slit that rolling support plate into two additional carriages, one infront and one behind the main gantry carriage. they can be smaller so you don't loose too much travel, and should both have a plate going down to the flat bar rail with bearings running on it, instead of the main carriage. then, half way along, you have a small block sticking out of the table that the main carriage passes over but that gets in the way of the support carriages that extend to the flat bar. put magnets on each carriage so they all stick together. whenever you pass the middle point of travel, the block stops one carriage, leaving beam support in the middle while the other carriage is being taken for a ride with the gantry carriage. when you pass the other way, that carriage stays in the middle and the other gets pushed along. theres a channel called makersmic that designed a corexy/idex hybrid printer with a similar idea. this way there will always be support in the middle of the beam without blocking the travel. i also suspect that the threads on the ballscrew will always push your flappy one way or the other so it'll rarely be upright to provide proper support, so if you find a very low friction material (PTFE Ikea chopping board maybe?) you could integrate sliding bushings into these support carriages that slide over the ballscrew freely, again leaving a support in the middle at all times. support from all sides no less since it can be a closed tube) the only issue i foresee with both suggestions is possible binding, but it might be worth a try. best wishes from austria!
I'm building a Root4 in half the size as yours, using 1600x1600mm ball screws. Should be stiff enough. I was hoping to see your video of the electronics being hooked up. Did you not record or upload that step? Regardless, your 2nd video in this series, assembling the X and Y axis' was extremely helpful. Thank you very much for sharing that. Well done and I hope to continue seeing more videos from you.
Thanks for the lovely comment. I didn’t record the assembly of the electronics as it wasn’t something I was very confident in and I didn’t want to give people bad information. I’ve recently built a completely new CNC machine based on a printNC
Doesn’t seem like it has enough rigidity in the XY plane to resist the forces when cutting. If the square tubing flexes due to gravity at those lengths then it can flex sideways with the same amount of force.
yep the whole machine has a lot of flex, even where the z axis mounts on. Its fine for my needs for no but ill be chaning it in the future to a printnc design
@@jamieclarke321 Great video very informative. I am currently printing out parts and was thinking about this same issue with support rail. You did a great job with a simple fix! I would also be very interested in the stl files!
@@jamieclarke321 if you do decide to share the extra modified pieces you made that would be awesome. I am thinking of making a similar sized machine and your mods would be helpful.
Great job so far my friend.. I would love to have the space to build one this big but mine is going to be 1200x1000mm ish.. LOL I love the way u built the CNC printed parts fro the runners along the Y-Axis.. I'm using 2060 extrusions for my Y-Axis. I bought pre assembled runners from Amazon with the V-slot wheels already on them but I'm struggling with the Gantry parts atm. What is the width of the Plywood ur using my bro? Is it 18mm or 25mm?? for ur gantry parts.. The same for the Z-Axis if u don;t mind me asking? Why the Torsion box method?? Is that so u get a completely flat surface bcos it's a great idea. I might try that myself now. I'm in the middle of getting ready to build my own table saw too btw. I have a loada steel 40x40mm Sq tubing 1000mm length. I have 25x25mm x 1000mm and 50x25mm x 1000mm sections also..I'm thinking of maybe changing tack and building a CNC plasma cutter from the steel. Won't be huge but big enough toi cut what I need and that's good enough for me.. I'm in 3-4 minds atm mate.. My brain is going 90 to the dozen right now with different ideas for so many different builds. I need to slow down and build one at a time.. LMAO U have built a brilliant CNC machine there. I sub'd liked and shared the video my bro,, Keep up the great work too btw. I'll be watching for more of this awesome content.. Salute from Dublin, IRE..
Building a CNC that big to. We have 1500mm X lead skrew. How bad is the whip on Y ? Curious. For that reason we went with toothed belt . Our x has really big whip, under fast acceleration😧 Could properly be fixed whit pretension 👍 What kind of spindle do you plan on using ? We went with a water cooled one. Was thinking of getting a cw3000 water cooler any opinion on that ? Great job so far. Greetings from Denmark 🇩🇰
Hi Kimberly, I don’t really have any whip on my x axis at 2500mm/min but my ball screws are 16mm diameter and 10mm pitch. 5mm pitch means the screw has to spin twice as fast to move a set distance, this could be what’s causing your screw to whip. What size screw do you have? I’m running a 2.2kw air cooled spindle on my machine as I didn’t want the hassle of dealing with the water for the machine, air cooled spindles can’t be run below about 6000rpm so that’s the advantage of water cooled
Would it help to fill the steel tubes with concrete or something like that? Should increase stability but also weight, and maybe the sheer forces in the center are too big - I don't know. Have you considered it?
Hi Jamie, nice build. In a few months I will build something like yours, maybe 3,2 meters long. I have to cnc HPL of 3.05m. For now searching looking and reading. I saw the request for the drawings, +1. Also you did mention somewhere about someone who did build a smaller one, any link? Maybe can you put it in the description? A side note. Do you realize that during milling the 40mm bars will go up instead of down? For this length I think that I will go for two 40mm 4-5mm thick bars. If I understand well, you did receive the leadscrews and screw from Aliexpress. Can you recommend the supplier? Any link available? Can you talk about that in a future video? Btw nice idea about the flipper to suppress the wobble! Thank you for your video, and did subscribe and waiting for part 3. ;)
I would highly recommend going for the printnc design vs the root Cnc which I have built here. This machine is not that good compared to what it could be. Dongguanksv transmission technology co is the name of the supplier I used on alibaba and I was very happy with them. They made the lead screws custom to my drawings and delivered them quickly for half the price and time of a uk supplier
@@jamieclarke321 thank you for your quick response. Great , top! But pitty that your not 100% satisfied with your design. You gonna change your design? I will look for both names.
21:35 at this point would a rack and pinion be a better path? Eliminating the the need for lead screws? Use the track for drive and remove the sag? I’m eager for the beam side but I really want to eliminate the lead screw
A rack and pinion would certainly be much easier. I also found after a few months of using this that the beam still sags terribly and really the whole design isn’t worth building when the machine is this big. Better to copy the avid Cnc design if your happy with rack and pinion or PrintNC if you want ball screws
@@jamieclarke321 I don’t think from this point here a rack an pinion would be hard to adapt the height is perfect really plus I think a shorter machine will help immensely but I really like the rest of the design
@@riz3nfpv306 there’s also a lot of flex in the spindle mount and the x axis can twist which also deflects the spindle upwards so while you may be right and I will consider adding rack and pinion for the Y axis it may be throwing good money after bad as we say in the UK
@@jamieclarke321 like the formula suggest. The longer you go the flex is horrific. How short do you have to go to make it a viable machine.? I’d really like to know that answer. Perhaps consider shorten X first that will cost you nothing but time.If that becomes good then, hopefully encouraged, you can try to use the sag in Y to your advantage on a rack and pinion?
Is this project alive? Have you any thoughts about its issues? In my opinion, a square tube will provide minimum accuracy and repeatability of 1-2 mm, especially diagonally. But maybe I'm wrong ;)
Hi tomasz the Cnc machine was finished shortly after this video and I was using it today. The machine has a lot of shortcomings, especially after being scaled up to 4ft x 8ft. It would be much better as a 4x4 machine, however I now believe the printNC is a much better design and I will likely be harvesting the parts from the root4 to build a 4ft x 8ft printNC
Hi Yakman, Sorry i wont be sharing the files for the side supports because they dont work as well as i intended and there is probably a better solution than this.
Just in the middle of using the machine for a large job, I’ll be up with a video about how I finished it as well as another video which will be a review of the machine and what I would do differently
Hello Jamie, what a great video and very helpful in my 4X8 table build. I have the machine all built and running on railing just like your Y axis flex support, ( flat strip) but mine is not traveling together on both sides causing one side to lose steps. So I am looking into your Y setup but will run into the sag like you have. So my question is, what are the specs for the Y axis support that you printed so I can kind of follow your design, because that's an awesome solution to the problem? Thank you.
Hi Dee, for the y axis I used 25mm steel flat bar mounted to the table. Then the bracket has 608 skateboard bearings inside it. These are mounted using eccentric nuts and eccentric bushings so it can be adjusted up and down. With the eccentric bushings you can release a bit of tension on one of the y rails if it’s binding up for you
I 3D printed m8 eccentric bushings like the ones listed here. linearonline.co.uk/acatalog/Eccentric--Stainless-.html# You can download the cad model from McMaster carr in fusion 360
Unsupported rails like you have (not to mention you have no linear proper stiff linear rails) will have a lot of trouble cutting in the center of the work area. The supports you made will only help with force from the top down but none of the other directions. You may wanna look a the print NC for some inspiration for a stiff and cheap construction.
Building big makes no sense if you can't guaranty that the rails (40mm steel box section) are perfectly straight! basics of mechanics if you want to be sure that repeatability of printed parts won't ruin precision...
Increasing the wall thickness doesn’t add much stiffness as it’s offset by the fact that it adds weight. For example a solid bar might by 10% stronger that a hollow tube
what is precision that you can have with this setup? Did you have something in mind when you have started building it? You said in middle you can have up to 3mm of vibrations ... so that is what i had in mind, and that seems alot if you are trying to cut something ... Btw, great videos :)
Hi Ivan, If you watch till a bit later in the video youll see i add a support system and im able to get the deflection down from 5mm to 0.5mm which should be a good amount of precision for surfacing the spoil board which will remove the last 0.5mm of error and should end up perfectly flat
@@jamieclarke321 I have saw later "invention" :) and i like it, but i am thinking maybe multiple of those - would make it even more rigid? I am in process of building my own cnc router 3+2 axis, so it is good to see what can be challenges ahead! Keep up good work! And thank you for reply!
"sorry but there is too much slop in that bearing assembly and there will be too much flex in your unsupported Y axis rails. This design is bad. It could cut wood but not much else and there will be tolerance issues. I have a better Idea for your gantry what if you leveled your table and put 2 skate wheels or in line skate wheels under your gantry supporting the weight of the Y axis. This would work similar to a follow rest on a lathe then the unsupported section of the gantry would only be the distance between the wheeled supports. " similar to a lowrider. As the Y axis moves it's continually supported evenly by the table. also you should make your x axis supported weight rest on top of your bearing assembly your putting the entire load on the side of your gantry bearings and non of those bearing are designed for axial loading.
I don’t put bearings to support the Y axis on steel flat bar later in the video if you watch all the way through you’ll see. I do a whole section talking about it
@@jamieclarke321 my bad this still isn't fully adequate your assuming all of your flex is in one direction. if you wanted to keep your rail straight you should keep the rail captive between the bearings this helps cancel out the bend in both directions. look at the v bearing setup designs i0.wp.com/www.rainydaymagazine.com/RDM2011/RainyDayProjects/CNC/BlueChick/AssemblyZAxis/ZAxisOnRailBig.jpg
Hi Jamie, you did some very nice work! At the moment I am also building a large version of the Root CNC 4. would it be possible to share your 3d printed parts? it would be my great pleasure. greetings and good luck!
