I’ve been poking at this build for the last month or three, in my spare time. It’s been taking so long because there are a few aspects I’m doing custom:
I’m using linuxcnc, so I get to do the electronics package myself
I’m using cncdepot’s S30C spindle, but… linuxcnc… so I’m doing all those electronics and pneumatics myself too
I’m using my own BLDC servos and custom build driver board, so even more electronics that get to be done myself (I’m an EE if you can’t tell plus custom 3D printed gears.
I’m building a mirror image of the 5x10 - all the wiring is on the left instead of the right, which has caused a few “take it out and do it again” moments.
I’m using constant tension springs to offset the spindle, since the servos won’t hold without power and a brake seemed overkill.
I’m keeping a photo journal here: http://www.delorie.com/photos/cnc2/ but there’s no descriptions on any of those, so feel free to ask questions here
That should be an interesting build. I haven’t used LinuxCNC since I used it on a PocketNC (now Penta machines).
I did like it when I used it. Have you used it on any other builds or is this your first try?
Also, if you want to post pictures here you’re welcome to. We have pretty generous storage so you’re welcome to upload as many as you’d like. You can put them on your original post and update it as needed too…
This is my second LinuxCNC machine, the first is at - no surprise - https://www.delorie.com/photos/cnc/ - and yes it’s made of WOOD. It was quite a learning experience, but I’ve outgrown it. That one used the parallel port. This one will use a Mesa 7i76E card. I work for Red Hat so I kinda gotta use our own software
As for photos, I’ve got 14 out of 72 terabytes of local storage assigned to that web server, and photo journals of my many many projects. I’m all set (but I"ll inline photos in the future, when specific to the topic, I suppose)
It’s not 5x10 but by the time I need that I’ll probably be on my second spoilboard Also leaving room for ATC’s tool rack and will eventualy add a rotary axis somewhere, and a vertical table. This spoilboard is enough for my immediate needs.
Also discovered the hard way (almost, I caught it before cutting anything) that the racks are not metric, despite measuring 4mm per tooth… turns out they’re pi/20 inches per tooth, which is 3.9898mm, despite everything else on this machine being metric.
I ended up moving that one cross rail forward a few inches so that the spindle can just barely reach. Making space for these was one of the reasons I got the 5x10 instead of the 4x8. I also realized the hard way that 3D printed brackets give you a known weak spot for when the tool change gcode is wrong. At one point I contemplated putting a soft fluffy shelf under the tool rack…
In the process of aligning everything I realized I needed an MPG, so I started on that, too. This uses a salvaged stereo knob, two DP4T switches, and a bunch of 3D-printed parts:
I haven’t wired up the MPG but it should connect directly to the Mesa card with a standard cat5 cable.
Future plans: I want to put sensors (probably switches) in each toolholder so I know which ones have tools already, along with a way for the spindle to test if it has a spindle in it. I also need to get an air pressure sensor.
That MPG looks great. The tool holder clamp posts look very usable. The plastic is printed in the direction of the force being applied which makes them strong… until you have sticky tools
And you got your tool breakage sensor on there as well.
I tell folks that every CNC needs a good 3D printer but not ever 3D printer needs a CNC machine and they look at me like I’ve lost my marbles. I think you demonstrated my point very well. The trick is to figure out where its best applied.
I didn’t realize how much I needed a 3D printer until I got one. Now I have three, with a fourth on the way. Missing knob? Print one. Need a bracket? Print one. Heck, when I was building my electric motorcycle, I printed a big nut for one of the engine mounts - “until I get a metal one” - then forgot it was there for months.
Weird DIN rail mount? Print it.
Tool holder stand? Print it, and the clamp too.
Tool setter in the wrong place? Print a bracket.
Can’t find a roll-in T-nut? Print one. Or ten. I’ve printed a ton of cable clips too.
It’s great for workpiece hold-down because the spindle will rip right through them without blinking if you misjudge DAMHIKT.
I’ve even got some printed samples of 40-4080 that I keep at my desk for testing other prints, like a clip that goes in the 4080 slot that lets you hang a CAT30 by the pull knob. That was printed, too.
I own just “one” 3D Printer now. A Ultimaker S5 with the material station and the air manager. It is truly a “printer.” You send it a file and you go pick the thing off the build plate.
I actually still have my original Lulzbot Taz 6 and I do in fact use it every so often. It is about 70% ABS prints from the S5 now and will probably last another 10 years.
But still it’s a direct drive whereas the S5 is a Bowden, I use it to print really soft TPU and the 1.2mm nozzle is great for large solid objects for jigs and fixtures.
For instance I will use the 1.2mm nozzle to print a rough shape for the jig or fixture in solid PLA and then mill it to exact tolerances.
That right there is absolutely huge for precision and time.
@djdelorie looking at the spacing of the tools/mounts on the rail in the photo posted, above, what as the driving factor on the spacing? Is that just a spindle nose thing or is there a dust shoe constraint or some other driver?
The primary spacing issue is that I don’t want the Z carriage to hit the tapers on the adjacent tools. My spindle nose doesn’t stick out below the carriage at all and I need to move forward about two inches to extract the tool, so the corner of the carriage comes pretty close to the adjacent spindles.
Starting there, I just spaced them out to a more convenient 5.5 inches as I had the room to do so with the number of toolholders I have.
I haven’t yet figured out what I"m doing about dust collection. My current thought is to have a removable shoe that the machine can remove on its own and store during tool changes.
Had I aimed the tool holders towards the back of the machine, the Z carriage would have been moving away from the spindles, and I could have placed them closer together. I just didn’t need to, and at the moment, the spindles are at Y=123" so right at the edge of my range.
Actually it is the AvidCNC part no. CRP841-10_350 (the plate that the tramming and spindle mount bolt to) that define the spacing of the tool posts.
Correct me if I am wrong @djdelorie but I believe you reversed the direction of the tool holder clamps to the front to negate that?
The problem is you don’t want to go to low for your spindle placement or you start getting weird lever action going on while cutting. That plate is very wide and thick.
Here are some images to demonstrate (Updated For Clarity);
As you can see, the tramming plate and Z carriage are basically the same width, but in my case, the carriage extends lower. If I had mounted the pockets facing backwards, then the spindle nose would be the limiting factor, but then I’d have to put the tools much closer to the working area, and I wouldn’t be able to see the tools from the console.
Also, I set up these shots with the MPG, so… it works!
For @da-kengineer-meister he was thinking of putting them along the side. When I did that I ended up with that 95.25mm + 25mm (half the width of the ISO30 tool holder) + 27mm (the thickness of my carriage plate) between each tool. The regular ABS over-molded ISO30 clamps would create an issue as they are 100mm long with the center of the tool being roughly 20mm from the front.
And that’s why commercial machines have a separate robot that feeds tools to the spindle one at a time
I think for our default setup, the only way to really pack in the tools is to run them along the front edge, so that the clamps and stands are on the opposite side of the spindle to the Z carriage. The minimum spacing should then be (diam(spindle)+diam(tool holder))/2 or about a tool every 2.8 inches - or actually limited by the width of the clamp itself.
A tool every 3 inches is about 20 tools across…
In my case, like I said, I might be able to pack them in more as long as I don’t move the spindle forward enough (Y-) for the Z carriage to get to the adjacent spindles.
I had to pick the most difficult thing on planet earth to make into a product At this point to assemble a prototype is costing me full price as to what I could sell it for. Minimum production run I can do and still make money is 10. Which is probably twice what I could sell
We shall see, right? I had fun trying though and that is all that matters.
plus custom 3D printed gears.
