I understand that this is an OX forum but am hoping I can get some input on the three options I have on the table. I am working on building a CNC router with my son who is 11 years old. I have some experience with a laser engraver but zero experience in the CNC router arena. I started out looking at the Xcarve and as I looked into it more, it seemed overpriced for what it was. I was able to set up my own Arduino and Gshield for about half of what they charge. I was able to get a power supply for 70% less, etc. With the Xcarve option, I am looking at getting the barebones frame, lead screw and wiring kit. The possible downside that I see with this route is the belt drive system. That all adds up to about $700. The other option I have is a full DIY with plans from somewhere like http://solsylva.com/, specifically the 18"x24" model due to the aluminum construction. The only real downside to that route is I have zero experience with working with aluminum or any metal for that matter. I don't want to invest $200-$300 into some aluminum that ends up being nothing be scrap metal. That route seems a little overwhelming. Finally with the OX, I don't have any experience with how the OX system, or any of the others mentioned work. The OX system seems like it would be more rigid than the Xcarve and is a bit more customizable and expandable. The downside is there is no kit (as far as I see) to assemble a machine the size I am looking for. Here is a list of 'requirements' for the machine that I have come up with. -Needs to be able to cut any type of wood (maybe some soft metal from time to time but the focus will be on wood) -Needs a bed with a minimum 18x24 -Preferably easy to expand -Needs to fit dewalt 611 (that is the router I currently have) -Mechanical/architectural setup preferably under $1500. I am sure there are other requirements that I should be looking at. I think a rack and pinion for the X and Y axis and lead screw for the Z axis is the best way to go for this application but am very open to input on that as well. The last consideration I have is that I am working with an 11 year old that has an 11 year old attention span. He is excited about the project and has enjoyed working on the electronics with me but I am not sure how long he will be able to stay focused on the frame/gantry build which is one reason for looking at a kit. Thank you in advance for the input. Nate
Hey Nates02gt, This isn't just an OX site. It's a DIY site. You're welcome to share with the community here any DIY'd contraption you can come up with. It sounds to me that one of the Openbuilds machines is right up your alley. You can find BOM's for the machines here on the site. Here is a link for the C-beam mechanical kit.http://openbuildspartstore.com/c-beam-machine-mechanical-bundle/ It has a good price and is a short yet sweet little build to keep the cubs attention. I recommend you gather pictures and video of different sections of the build (or just point out what needs to be tackled next) to present to the young one as sort a goal then build together. I wish cnc was this accessible when I was that age! Regardless of which route you take, feel free to post any questions on the forums if you hit any snags along the way. Start a build thread while you're at it. Welcome to the site. Joe
I started with a ox and progressed into building my own design 8x4 machine. diy is cheaper than buying a commercial one but it's still not cheap so you want it to work. You will most likely choose a part for a diy one for which you will seek advice and be told you want something better and so you seek advice again and another better more expensive option will be suggested. I suppose it does depend on what you want from a machine, I set out with similar asperasions and in the end my diy machine cost me £7000 to complete. A £2500 overspend, most parts I had forgot to price in, things like cable, cable carriers, electronics enclosures, £100 worth of bolts, circular saw blades to cut aluminium/steel, drills taps, sheets for the bed, connectors, heat shrink, I could easily go on for a few more lines of things that were not considered in designing the frame and linear parts. So it can quickly spiral. However I think had I not started with the ox things would most certainly gone terribly wrong and 6 months on id expect id still be making alterations. So no matter how much advice is available, really getting a feel for a machine before attempting a full diy build is crucial imo. 4 is number of rebuilds a machine will take before you get it right with all builds even kits. But the rebuilds with kits are a lot easier and cheaper, and it's in the ideas you have working with it that Spurs the rebuilds that really teach you the mechanics of these things, more so than any advice. Good luck with the decision.
Thank you very much for the input. I definitely do not plan on spending more that $1500 although I am a bit familiar with how projects like this can end up costing more than initially planned. I do like the idea of the plate maker, however I am quite certain that the kit size will end up being to small after a very short time. Do you guys have any guidance on using the C-beam linear actuators for a build with a stationary bed? I like the idea of using something like that over the belt system that is on the standard OX build. I guess a question with that though is if I plan on cutting wood with the machine 99% of the time, would it be overkill to go that route? Would the belt drive give me the accuracy and resolution for detailed artwork? I know that I want my bed to be a minimum of 18"x24". Ideally, I would like either a 1000x500 or 1000x1000 but I don't want to go too big as I know that the rigidity of the frame will be compromised. I guess one route I could take is starting with the plate maker and then building another machine after that, I just have limited room as I am working out of a small garage that is already quite full. Nate
Hello Nate, If you are okay with 800*800mm you might go with the Acme setup. After that the GT3 (GT2 3mm) will be good for an up to 1220*1220mm hobby machine. If you go for semi-pro than rack and pinion might be best. I'm looking for a easy to add rack and pinion system myself for an 1280*2780mm Plasma CNC. What will you be cutting? i know you say wood but what do you make out of it? -Ronald
What do you mean a rack and pinion system? All you actually need is a mod1 rack and a pinion. All the spring loaded stuff is a waste of time, they just add backlash. Just rigid mounted with a lil be of preload. I get o.04mm backlash out of mine this way. Though I personally would only attach to something like a c beam, standard 20 profile will be too flexible to get a constant preload on it. Sorry just read that back, and sounds a little patronising, wasn't my intention.
P.ry is in the process of building a more rigid ox, taken from elements of my hox design. Which would be even more rigid still imo. Maybe p.ry motor belt and plate arrangement with my hox h beam arrangement? Check it out here: http://www.openbuilds.com/threads/the-hox.3217/
I didn't say anything about spring loaded , but yes, I wasn't going spring loaded but was thinking about a bit of damping with rubber spacers, or soft plastic. The rack I might lasercut and see how that turns out, the pinion for sure I'll machine or just buy. There are also ways of putting a belt in the V-Slot and let one run on top of it (will post details later if it works, hard to explain in a few words here!). -Ronald
Honestly, you don't need to, that rack needs to be as rigid as possible, any dampening will increase backlash. I know the lines your thinking on, I had all the same thoughts before I fitted mine, and besides those spring loaded arrangement are £200 or $ I forget, and you don't gain anything over a normally mounted rack. But if your concerned about vibration or alignment then id suggest spending that money on improving rigidity in the gantry and axis and then its money well spent as you have made two improvements. Also those spring loaded ones can jump gears if you jam, wrecking the rack and pinion. A broken endmill is much cheaper. And your introducing a way of find unwanted backlash. you'll find that you will be hard pushed to get any sensible reason from the manufacturers of them for fitting one. As there isn't any. Bolting you rack to a nice steel or aluminium bar and fixing to your profile would be money better spent and will achieve better results I guarantee it. I running mine with a 100kg of preload. You won't get that with a sprung pinion, it would need to be a car suspension diameter spring. The professionals use around a 1/4ton. You do need a planatary gearbox to achieve a high preload, but you will get more preload with a direct drive nema 23 than the sprung pinion.
Ronald, I am not sure what all I will be cutting but here are a few examples. Of course I will just be cutting out pieces for each of these but I am currently using a scroll saw for most of the work. Some of the parts on the truck are cut out with a laser. So if I just increase the C-Beam linear actuator from 500 to 1000 as well as all of the other frame pieces or would it be more complicated than that?
You can increase the cbeam to 1000 pretty simply, had this conversation on another post at the same time. Might be worth chating with this guy who's doing it. http://www.openbuilds.com/threads/c-beam-double-x.3730/#post-23369
So I decided to go ahead and order the C-Beam 'kit'. I added a few things like limit switches and the end plates. The next step (sort of) is software. We have been playing around with Vcarve Pro for the past several weeks and love the program. I have not taken the plunge on buying it yet. I know many in the community use sketchup with sketchucam. Based on the pictures I posted above and my son's desire to cut out wooden legos, would the community suggest working with sketchup/sketchucam, vcarve or another software application? I have the Arduino set up with the Gshield and steppers so I think we are good there. I have been playing with Chilipeppr and it seems like a great place to start but any other suggestions would be great as well. We primarily run Macs, but I do have Windows and Linux loaded as virtual machines. I will start working on a build log as soon as things show up and we get the project underway.
Congratulations on your decision. The beam is a great machine. From a software standpoint it sounds like you're on the right path. You're trying different programs to see what's out there. Definitely try SketchUCam. Fusion360 is turning into a popular CAD tool. Its free for a year then requires a very reasonable payment plan. I believe you hit the nail on the head with vcarve pro though. Aspire, vcarve, etc are all well known for their ease of use and quality toolpaths. Forum member Hytech2k has some pictures up of high quality sign work made with the aspire software. I think ultimately you'll end up there there (vcarve), but Sketchucam should be able to handle wooden legos and is a fun plugin in general. I go to it for 2d geometry and patterns. Btw, Forum member Dave the Swarfer maintains Sketchucam. If you have any GRBL related questions or requests, visit the maintainer Sonny Jeons GRBL thread. Joe
