Monthly Archives: November 2014

The man in black fled across the desert, and the gunslinger followed.

You know, I was trying to find a good quote or reference to use as a title for this blog post. Since this post is supposed to be the “I’m finished!”-post, I needed something to signify that. I thought about going the Borat route, Great Success!, or perhaps a Douglas Adams quote (you know which one I mean). Both of those would relay the success of the project, and the fact that it’s finished.

But that’s not how these things work. Anyone that’s ever truly dedicated themselves to build something knows that.

Instead I went for this one. I’m not going to explain it, since that would ruin one of the best book series ever written, but should you have read them all, you’d know. You’d understand.

 

Anyways, here’s the video I’ve been promising! It’s a bit of a mashup, showing a quick fly-by of the machine, some 3d ballnose profiling and some straight up end mill slotting action. Pure porno.When you’re done watching, go read all the blog posts if you haven’t already. They’re fun. Everyone that’s read them all will agree with you. (Only I’ve done it that I know of so far, and you can’t disagree with me until you’re at least nr 2).

http://tumblebeer.com/project/cnc-v3-tumblemill/

You can find all of the blog posts linked here.

Upgrayedd

That’s with two D’s for a double dose of my pimping.

Lately I’ve been upgrading the CNC, something also referred to as “pimping”. As of this moment, the machine is actually… wait for it… Finished! That’s right, by adding the things I’ve called “final pieces of the pussle”, I’ve done everything I initially set out to build. I’m going to do a small video where I showcase all of the features, and perhaps even a milling job. I’ve already milled quite a lot of aluminium, with great results, but nothing that I’ve managed to film. But for now, I’m just going to try and describe the things I’ve built since the last post.

I’ll try to remember all the things I’ve built and/or added to the machine, but it’s been quite a few of them. Let’s see, I’ve built:

1. A dust boot.

2. Another dust boot.

3. A third dust boot. Not really, but I’ve modeled one that I’m going to build eventually.

4. Started working on a vacuum table.

5. Added limit and homing switches.

6. Added an air blast and mist cooling setup. With a quick regulator for coolant flow.

7. A crosshair laser.

8. Chip guards.

9. X-box MPG.

10. Auto tool height setter touch plate.

11. Touch probe.

12. Clamps

13. Final pieces of the puzzle.

 

1. A dust boot

I keep my cnc in the living room. Actually, I keep my cnc in pretty much the only room we have. This means that both me and (more importantly) my significant otter have to live with everything that gets thrown out of it. Without a dust boot, that is a lot. Dust, chips, burnt rubber (not intentional), various cutting fluids and other unspeakable horrors. At least they feel like unspeakable horrors when you find them between your buttcheeks when waking up in the morning. As such, I’ve spent a lot of time trying to build the perfect dust boot. I haven’t succeeded yet, but I’m getting closer. This first attempt(first working one at least) does its job superbly¬† at containing dust and wood chips. It’s a floating dust shoe, which means it doesn’t move up and down with the z-axis. Instead it rides on the bristles, which avoids them getting crushed on plunges. It’s held in place with linear bearings riding on aluminum rods.

Dust boot in action

 

2. Another dust boot

This one isn’t nearly as pretty. It does however have two very important features. I can see the workpiece while cutting and I can using cooling. It works, but not much more. My next iteration will incorporate the features from both versions to form a perfect bust boot. Like using a hobo and a rabbit to make a hobbit.

 

4. Vacuum table

I haven’t really gotten around to this yet, but I have a bunch of vacuum ejectors (venturi effect type thingys) that I’ve been playing around with.

 

5. Limit/homing switches

This was a pretty major piece that I needed to fix. Limits are good to have to avoid crashing the machinea, but what I really needed was the homing to autosquare the gantry at every startup. The switches are inductive proximity switches (I’ve tested them, and 9 times out of 10 they’re dead on according to the dro, 1/10 they’re 3 thousands of a millimeter off. That’s impressive.). I had some trouble finding good mounting spots, but that was nothing compared to the trouble of fitting even more cables in my e-chains. I had to use flat UTP cable. Noise isn’t an issue, even though they’re not shielded, since I use 15V and run them straight in to an optocoupler. To be safe, I also generated the voltage with a traco switchmode converter, to keep it from having a potential against anything else in the system. The homing is dead on accurate like a said, mainly due to a “double tap” macro I wrote and added to the mach3 homing function. I’m not going to put a separate picture here, it’s up top.

 

6. Coolant

I added an air blast/mist coolant system to lubricate, cool and blast away chips when cutting alu. I use 99.8% isopropanol alcohol when cutting. It’s great for alu, leaves me with a mirror finish on the climb side. There’ no cleaning, since it evaporates without leaving any residue. Since I bought a real cheap mist thing from china, I also had to add a high tech regulator for the coolant flow, see pictures. I’m going to upgrade this to an IV bag next week. That’ll be fun.

 

7. Crosshair laser

This is a great addition. It’s a small laser mounted to the spindle-mount. By clicking one of the shoulder buttons on my x-box controller, I turn the laser on. I can then place the cross wherever I want my zero, then click the other shoulder button to execute a macro that moves the bit to that position and zeros the dro. Since reflections can make the exact center a bit hard to see, I also added a pot to set the brightness of the laser.

 

8. Chip guards

Even with a dust boot, sometimes a few chips fly out and land on my rails. I didn’t like that, so I added a couple of removable walls made out of cardboard. They’ll be replaced by acrylic later on.

 

9. X-box 360 controller MPG

This one is great. There’s a plugin for mach3 to use a controller as an MPG, and it’s perfect. Custom macros on every button and fully analog speed adjustment. Wireless as well, so no hassle with stuff getting caught.

 

10. Touch plate

A piece of pcb with a crocodile clamp that plugs in with an audio jack. Great for setting tool height fast and simple.

 

11. Touch probe

This one is also great. When engraving, I need really flat surfaces. That’s rarely the case, so I built this probe to autolevel. (I use g-code ripper for autolevelling). The switch is a standard micro-switch, the repeatability is good enough.

 

12. Clamps

CLAMPS!

 

13. The final piece

This piece and the one on the other side were the last two things I needed to put the machine for it to be completely finished. They’re milled and engraved by the machine. The result is just perfect, couldn’t be happier. It cut the alu like butter, left a mirror finish and the accuracy of the parts is better than my calipers can measure.

This means that the machine is completely done. I’m just going to make a final video to show the machine and all of its features, then I’m off to my next project. Hopefully that will be my thesis work, still haven’t managed to get in contact with anyone that wants me. And yeah, I made this video to attract some viewers. Because you know, bitches love Arduinos.