One of the things I’ve been working is a set of gcode subroutines meant to make easy to write gcode. Well, in the end you write very little gcode if you use it. Here are some examples:
So, for example, here the code for the hexagon pocket milling:
#<s> = 30
#<h> = [SQRT * #<s>]
o<i3_c_new_group> call  
o<i3_v_add_vertex> call [#<s> / 2] 
o<i3_v_add_vertex> call [#<s>] [#<h> / 2]
o<i3_v_add_vertex> call [#<s> / 2] [#<h>]
o<i3_c_mirror> call    
o<i3_do_cut_mill_by_layer> call    [-1]  
Most of hard work has been done, there’s some cleanup and documentation left. At some point I would like to release this code as open source. It makes really easy to create paths for simple parts (please note all the generated paths account for tool compensation, not G4X).
Currently I’m doing some modifications to my Sherline lathes in order to add a cover, very similar to the one on my cnc mill. This will result in a really big changes in the lathe look. I don’t feel comfortable doing these brutal changes to these beautiful machines, but it’s something I need to do.
Of course there are always some things that go wrong. If I were a professional machinist working on big machines I will be dead for sure. So be careful when you start cutting on a corner using traditional milling (not climb milling; I’m not saying climb milling is more secure, btw).
I’m doing a lot of work with my cnc mill. I’m working on and with a really useful set of gcode routines that I will like share at some point.
Finally, here’s one of the more simpler yet useful accessories you can make for your Sherline mill/lathe, the “no hammer” (not my idea of course).
Can’t believe didn’t did this before.
My actual cutting parameters for aluminum sheet:
- Material: 1100 aluminum (I’ve cut 1mm and 2.5mm sheets)
- Feed: 600mm-min or 24IPM (I’ve used 800mm-min, but now I’m being conservative)
- End-mill: 4-flute 1.5mm carbide. I’ve used 2-flute and 3-flute; the more flutes, the more quiet the cut.
- DOC: 0.2mm
- Spindle speed: max (2800 rpm)
- Lubricant: some WD40
- Finish pass required.
A lot of peoples says 1100 is a nightmare to machine, but as always, you just need to know it. I settle in these parameters by a test-error process, but I don’t now if these are the optimal ones. I just know these values work for me. And of course these small carbide end-mill would enjoy more rpm.
For 5052 I’ve used the same parameters, but you need to lower the feed a bit; a friend broke some end-mills at 800mm-min because of my speed thirst (nevertheless that was fun).
One last thing… the part in the photos is 2.5mm thick, so it was strong enough to withstand all the cutting with just a few screws. If that were a 1mm sheet more screws would be required.
I’ve been building a leadscrew cover for the Sherline’s I’m going to sell. I think this is a must on any cnc machine.
I like the classical accordion-like cover, originally designed by ixen-cnc.com. So far, the main obstacle has been to find an appropriate paper. But I guess here is: Fabriano Tiziano Paper. This is a acid-free, 40% cotton, 160 gsm drawing paper. Very high quality and strong paper.
Folding has a trick; you should use a ballpoint pen to trace each line, pushing hard (kind of emboss). Even if you do this, folding is difficult, though not impossible.
And the best thing… you have a lot of color options!. I like the black-red combination.
DARwIn-OP is a humanoid open source robot developed by some prestigious universities. It’s not just a toy, but an advanced research platform; commercial version cost USD $12,000.00.
Some time ago I found a guy in my city that is building this thing on their own and I was amazed; that involves some serious metalworking, electronic and programming skills. He had some trouble because the largest part has a size larger than the cutting area of his machine (a 5400 Sherline CNC mill), so I provide my machine to do the cut; that was a lot of fun. So here is his site: http://openrobot.cl.