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My DIY X-Carve... It lives

Not long ago… well… ok… i’m lying.

About 6 months ago, i embarked on a rather strange journey. I decided to build my own CNC machine… I had no real expectations, ideas, goals, or projects in mind. I just wanted to spend the winter doing something interesting, and hopefully have something fun at the end.

Well… here it is 6 months later, and i have to say, I’m kind of proud of myself.

Using the open-source documents provided by Inventables, and a few modifications due to cost / necessity / availability… I have my very own 1000mm X-Carve.

Granted, it’s not pretty, and painted / powder coated like buying the kit you just have to assemble… but it’s mine, and i love it just the same.

I started off, with an idea, and a butt-load of ignorance. Slowly, i’ve wittled one down, and carved the other out of pure determination, and some cash…

Starting with the the easiest stuff first, i spent time sourcing cheaper alternatives for parts… mainly… the bearings and wheels… I just couldn’t bring myself to pay so much for such simple items. Don’t get me wrong, Inventables prices aren’t bad, but if i don’t have to pay retail, i won’t. However, i did purchase my rails from inventables, and their support staff is awsome… For some odd reason, one of the 1000mm rails sent to me was 5mm short, they cut, and sent a new one out immediately at no charge, and in all honesty, if i hadn’t scrapped the first one through frustration, i would have shipped the defective one back to them…

I ordered a rod of Delrin from shmeebay, and the bearings i picked up locally for around $0.68 cents each. The flanged bearing for the Z axis i had to order, but it was only around $2 with shipping, so not that bad.

I turned down the Delrin rod using a friends lathe, and made all my v-wheels… it was at this point i realized i didn’t buy enough to turn off the idler pulleys, so i just used some large bearings instead. If you keep your moror pulley, belt, and bearings in line, they actually don’t slip off…

Next i sourced some local 1/4" 6061-T plate, and set to manually milling, drilling, and tapping the gantry end plates. Also use the stock to mill and drill the 2 Y rail end plates… It wasn’t really that tough of a job, but doing it on a drill press with modified bearings made it kind of awkward… Truth be told, i think it’s time i retire that drill press, as it was a cheap Black & Decker bench top model i bout 15 years back for about $90, and i’ve replaced the bearings, and table a few times already.

Once the plates where done, i sourced some 1/2" 6061-& plate, and milled out the spindle mounts… I decided to make two, as my spindle as of right now is just a crumby classic pro series RotoZip… It works, does the job, but i had to modify the plans of the mounts to fit, as this spindle is oval shaped… i.e. 67mm, and 65.5mm if turned 90 degrees…

I sourced my drag chains on shmeebay, total cost for both drag chains was around $16, but coming from china meant i had to wait almost a month… eep…

While waiting, i shopped… bought my motors, pulleys, and belts from shmeebay as well… belt and pulleys came as a package deal, 5 pulleys, and 2000m of GT2 belt was around $20. motors were 36$ for three (didn’t realize i needed four till later, bought the 4th from inventables)
Used the left over 1/4" stock to make the mounting plate that goes on the Z-Axis, and bought a 8mm TR8*8(P2) 4 start acme thread lead screw from openbuilds.

I used a small bit of the 1/2" aluminum to mill and drill out a nut for the lead-screw… again, had to wait a month for china post to arrive so i could tap it for the acme thread…

I ended up cheaping out, and used some shielded ethernet cable to run my stepper motors, and built a project box for the arduino and connectors etc…

Limit switches were 4$ for 10, again from china, but they work well…

Anywho… Enough about the boring stuff… here’s a video of the the second cut attempted with the device (first had to be scrapped because i accidentally unplugged the USB cable… lol)

I hope you guys enjoy, i’m a much wealthier person now, not in cash mind you, but in experience… by doing as much as possible my self, i saved a small bit of coin, and learned heaps about the ins and outs of the machine.

Side note… you can see there’s only 1 of the two mounting brackets are attached properly in the video, that’s due to misplacing 2x 5mm x 45mm screws… it’s been resolved since :smiley:

3 Likes

very nice. did it save you money or was it work passion over money value.
ether way. your more deserving of your carve than most of us to mill the main parts your self, rather than just buy them.

ended up saving me quite a bit of money. the stock used to make the gantry plates, end plates, and motor mounts cost me a total of $23, and i didn’t bother to charge myself for machining time :smiley:

The v-wheels ended up saving me almost 1/2 of the cost over purchasing them.
Saved more than 1/2 using oversized bearings rather than purchasing idle pulleys, but i do plan to eventually replace them with the real deal.

Drag chains were definitely cheaper, however, the time it took for them to get here, and the fact that the hole patterns on the end pieces were different, meant i had to fabricate my own mounting system. Fortunately, i had some spare angle in the garage, and i simply cut lengths off of it, and milled the inside corner to a 90 so the mounting screws could sit flush.

However, my alterations do have some drawbacks, and I’m unsure if they affect the kit version…

namely, dust clogging the Z-Axis lead screw&nut causes the Z-axis to miss steps, I’m thinking of addressing the issue with by making a telescoping lead screw cover. i also think i will also grease the lead screw on the z-axis once the dust shielding is in place… That should help keep the lead screw and nut running smoothly.

I’ve also noticed dust and debris are starting to get onto the belt, and GT2 pulleys… I think i will address that by fabricating a metal “box” or shell to fit over the assembly, and attach to the idler screws…

I’m also having issues with the homing switches… This is mainly due to noise interference, and i believe i can solve the problem by adding a small capacitor and resistor to each switch at the controller board to filter out the noise, and put a stop to the false positives… Currently, I’m running without a homing sequence, and switches by making sure my g-code origin is centered onto the part, and using that as 0,0,0 before starting the machine… This however, means that i cannot adjust or move the spindle in any way or i lose positional accuracy between operations. i.e. no tool changes for now… :sob:

I also have a plan to “shim” the gantry rails… by design the two rails are separated by a gap, on the 500mm version this probably isn’t an issue, however, on the 1000mm version, this gap, and the span distance introduces a weakness. The spindle can have a tendency to torque these rails, even slightly. So that means on forward sweeps, it may torque, and dig in a bit deeper than intended, and on backward, drag, or lift up a bit… My ultimate goal is to machine aluminum, so i need to address this issue… By adding a solid piece of aluminum between the two rails, and screwing the rails to this shim from both sides, i believe it should solve this issue with minimal cost, and very little alteration to the rails (6 holes on each rail to accept the m5 screws at alternating heights)

All in all, i think it’s a great learning experience, and I’m actually having more fun “tinkering” with the machine to fine tune it and problem solve it, than anything i’ve attempted to carve with it…

My next goal is to completely replace the MDF waste board, and use 1/4" aluminum plate, or 1/8" steel plate if i can get either at a reasonable price… This should further increase rigidity of the overall machine, as well as give me a more reliable clamping surface, and allow me to introduce mist, or flood coolant.

It sounds like you’re going to be doing the same type of X-axis stiffening mod that quite a few of us have done. I have a video of how I did it in this thread: X-Carve Maintenance/Troubleshooting Videos - Add Your Own!

There’s also a few other stiffening mods you may want to consider, especially if you’re interested in quantifying how well each one works since two of them don’t require milling through the rails. These threads may prove interesting to you:


2 Likes

The first mod with video you posted is pretty much what i have planned… instead of steel, i’m going to use aluminum, but that’s just to save weight, and really, a personal preference rather than anything structural. The main goal is create a rigid, solid assembly that is less prone to torque.

As for the second mod, where they use the bolts as “spacers” there’s an inherent flaw with that mod… Namely, vibration will over time cause those to “rub” free… because the only force holding them in place is tension, it means the center of the bolt shafts are free to vibrate or resonate and rub the inside, over time, this will get worse, and could potentially cause the rails to spread apart, as there is no force to keep them from doing so.
But agian, i plain on playing with aluminum and brass etc, maybe even some mild steel, so my requirements may be higher than theirs, where that mod may be just enough for their usage.

@ChrisMay Give the 60 min mod a try, In that mod, the bolts are not really spacers, but rather just provide the force to clamp the bars down around the maker slides. I haven’t tried to calculate the coefficient of static friction between the bars in the maker slides, however it would take quite a bit of force to overcome. If you have aluminum bars laying around, this will not take long to quickly try out and you might find its plenty rigid for anything you would do on the X-Carve.

Agreed, however, the shim method seems to be a stronger solution as the rails themselves are the clamping surfaces, and the shim keeps them from torquing. This method gives rigidity against torquing, bowing in / out, and has the advantage of being only 1 additional part, and some screws vs 2 additional parts and screws. In the 60min mod, granted, you’re not drilling holes into your rails, but you also have far less protection against bowing outward, as well as torquing.

my thinking on this is:
because you’re only clamping to the surface of the rails, they are still free to flex, and distort along with the secondary set of flats, because they aren’t actually attached, the screws are still free floating along the length of the assembly. i.e. up and down movement is still possible, granted, it will take more force, but not nearly as much force as if you went through the rails. going through the rails means the rails themselves keep the screws from moving up / down, and in/out, plus the addition of shim between the rails, means there is solid surface contact between the rails throughout the entire length, no gaps or spaces between.

Now i’m no physics major or anything, and trust me when i tell you that i’m no expert here. I just think the through-hole shim method would be much stronger from all directions.

Seriously, don’t get me wrong, all of the proposed ideas are great, and will work, but i’m a bit of an ignatz, and whenever possible, i will use a sledge hammer to drive a finishing nail.

I mean… i’ve already started toying with the idea of replacing the rails with steel flat bar with the appropriate profile milled out. the v-wheel assembly with that of solid rod dowel, larger beefier bearings, and steel wheels, as well as upgrading all the end plates to 1/4 steel, and the steppers to some really beefy nema 43’s

Yes yes yes… i know… overkill… but isn’t that the point? I mean, it’s great if you’re happy where it is, but wouldn’t it be that much better if you could incrementally upgrade everything and end up with a machine that can cut and carve anything you put in it? A machine that can cut steel, can cut any material softer than steel…

It could just be me :slight_smile: That’s been known to happen. But i’m always looking for the next project, and while i slowly buy, build, and pilfer the items i need to rebuild the entire machine for sh**s and giggles, i can still use it to dink around.

Did you end up using the Inventables X-Carriage?
I have made one too, but was 3D printed parts to get it up and running and now needing to exchange them out. I had to alter dimensions on holes etc from Inventables X-Carriage for mine to work with my locally sourced rails, wheels etc.