Arduino milling machine | Hacker News Reader

Arduino milling machine

rikkipitt.com

48 pointsrikkipitt26 comments

I'm interested in Step 2. How do you plan on generating the G-code from a shape (in any of the various formats)?

I'm lazy and mostly a software guy, so I have been looking enviously at these: http://www.ebay.com/itm/3040-CNC-ROUTER-ENGRAVER-4-AXIS-MILL...

That too looks a decent machine. I toyed with building my own and got in touch with a few suppliers of CNC threaded drive rods. Some of the prices of these units seem pretty reasonable and probably a better bet in terms of price that going completely DIY. As for the G-code, that is going to be the hardest part for me too I think. I was wondering if Google Sketchup with https://sites.google.com/site/sketchuptogcode/ might be an easy route in to the scene?

CAM tools turn a model into a toolpath. I use MeshCam.

Have you seen Shapeoko? They will soon have their third iteration, but even the second one is great...

That's a lovely looking piece of kit, have you had the opportunity to play with one?

Yes, I am halfway to assemble it (done the mechanics, now comes the belts and wires).

Let me know how it goes and what you think of it. I'm really interested to hear more about it.

My local makerspace has one, though I've not tried it myself. IIRC it's using a custom bracket (3d printed) to hold our dremel, but is otherwise should be standard.

The one problem I remember seeing was when somebody's laptop was running it and went to sleep and they weren't able to get it to resume the job when it woke up. Maybe there's a way to do it, but just making sure your computer is set to stay awake avoids the issue entirely.

Most 3d printers which also use gcode, have an sdcard slot. Load your gcode file onto the sdcard, plug it into the printer and print from there. You dont need a computer connected at all, so nothing to go to sleep.

The 3d printers, yes. The Shapeoko 2 runs off of an arduino and gets its data over a serial connection.

At least that's my understanding of it. I've never used it myself, only watched it run for other people.

I'm a middle-school CS teacher; the woodshop teacher and I have been collaborating on using a Shakeoko at our school. It works great!

http://burks.girlsms.org/maker/?p=115

Would really recommend using Tinkercad for the models. It's quite nice, and really easy to do actual dimensioned models(i.e. this bit is 3mm wide type stuff). I use it all the time for my 3d printer

I would love to hear more details, specifically the stepping motor setup, the Milling machine (Sieg X2) and various mods needed, did you add DRO's, etc.?

The Sieg X2 is not a milling machine. It's a drill press with an X-Y table. Milling machines have spindles built to handle heavy side loads without loss of positional accuracy. Drill presses do not. On many drill presses, if you run the spindle all the way down, you can wobble it slightly with your hand. On a mill, the spindle will not move when you try that. The spindle bearings and heavier construction required are why a mill costs much more than a drill press.

There are also CNC routers. These are for wood, some plastics, and maybe machining aluminum sheet. Those are cheaper than real milling machines. However, ignore anything that tries to use a Dremel tool; you'll just burn out Dremel tools. Bottom of the line for a CNC router motor is something like a $99 Bosch router. Here's a startup that has a low-end CNC router for about $1000: https://www.inventables.com/technologies/desktop-3d-carving-...

Here's an overview of low-end desktop mills:

http://makezine.com/2014/03/20/desktop-mill-roundup/

The Pocket NC, if they ship it, looks interesting - that's the first 5-axis mill for hobbyists. You'll need very advanced software to run that thing.

Many serious home machinists get a Sherline mill. (http://www.sherline.com/prices.htm) They have a good reputation, but it's about $2K for a rather small CNC mill. There are lots of small CNC machines on Alibaba, but quality is unknown.

If there's a TechShop near you, get a membership and use their CNC mills and routers. You'll get better results than with any of the low-end machines.

Sieg X2 is a milling machine. Square column, adjustable gibs, R8 spindle. It's more capable and rigid (but not as nicely finished) than the Sherline.

The one illustrated has a drill chuck, but yes, you can put a collet in it.

I have to admit I'm just turned off by it being sold by Harbor Freight. That's usually a bad sign.

It's all speeds & feeds. Even if you use a drill press you can replace the bottom bearing (better still, use a few stacked ones) and reduce the load for your final pass and you can get surprisingly accurate workpieces out of a relatively cheap setup. Not everything has to be made to 0.0001".

If you're going to work wood then you should be fine. For light metal it will work too (aluminum) with some slop, for steel it probably won't work unless you go real slow.

In the end the mechanics are not the biggest part of the outlay, but if you're going for cheap every little bit helps.

The Sieg is a bit better than a drill press (not much though, I'll give you that).

So far looks like grbl flashed to Arduino.

What is the budget for your machine? I'm also very interested in CNC and interested to see further progress and part 2.

I was hoping to see more of the electro-mechanical ideas behind the device. Did you ever complete it?

I took a bit of a break during the latter part of last year, but I am writing up another installment which goes into the interface between the Raspberry Pi, the stepper motor, and the physical milling machine. I was in two minds of whether to build a machine or buy one. I'm planning on using the system with both options when I get chance.

Very curious, how did this get onto the HN front page?

As the author, so am I! I thought I'd repost it and miraculously it got to at least position 30...

Now that the site is struggling, and I can't look it up... is there a follow-up to that post, or is that how far you got?

I was stuck on a train (typical timing hey?!). I've got the site back up, but it needs a bit more fettling. Is it working your end now? I'm currently writing a part two which extends on what I started last year.

Typical timing?

You posted it ;) Can't really complain about this!

I know! I posted it roughly 6 hours before it hit the front page. I really didn't expect it to get as high as it did. Sysadmin on a packed train isn't fun! Thanks for all the supportive and useful comments guys, really appreciated. I'll be sure to finish off the next article when I get chance. The site should perform a bit better soon. I added a nodebalancer, just waiting for the DNS to propagate.

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