Revisiting the 3020 CNC & General musings

Been a few months of non-tinkering really, Just had a heck of a time getting anything useful printing in the D9………..Finally solved that issue – combination of badly cut PTFE tube and poorly machined throat caused major under extrusion and, well, that combined with two kids, a wife working away often meant zero time to actually tinker……

Anyways, in that ‘why the hell shouldn’t I go buy something that ‘just works’..’

I saw the Snapmaker 2 on kickstarter and got the old braincells working,

I have at home currently several devices that are taking a bunch of space

So after seeing the kickstarter I Decided to try to sell the 3020 on Facebook marketplace 

After several dozen people “interested” and several hundred messages, I now fear for the future of the human race having any semblance of collective intelligence  and have decided to keep the 3020T

Revisiting my earlier adventures, The CNC, being a parallel port version won’t run on windows 10, nor will that little dongle thingy I purchased

So, I purchased a new little dongle thingy –

It’s a rather clever little GRBL shield Which doesn’t have any Driver chips bulit in! it just wiggles the relevant data lines of the DB25 port in the back of the CNC controller…..

It’s alive again!……now back to the fun of calibration and figuring just how to use it, whilst allocating my decreasing waking hours to having fun tinkering…….

Ramble over,

MGN12H rails small tweaks to perfect…

Ok, the rails are on and working a treat, kind of…

The right angled fittings I purchased to secure the 20×20 extrusion to the 40×40 have some little tabs on them, I can’t find any readily available way of securely making this connection with off the shelf parts so i’ll have to grind down one side’s tabs…

The slight amount of pressure this tab is putting on the extruision is enough to twist it and stop the MGN rails from running smoothly!

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A secure 20×20 extrusion. But slightly twisted due to the small lump
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View from below…if I add a little drop down to the right hand carriage, it’ll be easy to re-use the existing limit switch by mounting it on the side of the 2020

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Close ups of the existing limit switch and the protrusions on the right angled mounting block.

Overall, minor things , but shows you should plan things a little in advance and test fit stuff before ‘going for it’

Fortunately this is nothing a quick angle grind and carriage print can’t fix….which means re-assembling the original printer to print a new bit, D’oh!

MGN12H crappy linear rail bearing blocks

What’s more sensible than spending $9USD on a basic, possibly non working chinese no-name bearing block?

……..Spending hours and a few quid trying to do ’em up!

Parts I’ll need…

  • 3/32 Drill Bit (or possibly 2.4mm if it needs some play) …………..[edit, turns out a 2.4mm is too small! Looks like 2.5 is the go]
  • 3/32 Ball bearings (bound to loose a few)
  • Something to drill with
  • something to clamp down the carriage without damaging it

After a few minutes with the calipers and Tinkercad, I give you………. Continue reading “MGN12H crappy linear rail bearing blocks”

Chinese ‘cheap’ clone linear rails MGN12 Beware and a teardown

The Cheapy ‘Hiwin’ clone rails and blocks arrived a while back and they haven’t really dissapointed. By that, I mean, I kinda got what I was expecting. Still, only a small premium paid and 3 workable carriages / rails……

Continue reading “Chinese ‘cheap’ clone linear rails MGN12 Beware and a teardown”

Chillipeppr, GRBL, JSON and CHROME

My little CNC Controller
My little CNC Controller

Real life’s taken over somewhat, with three kids (one 6 months, one 3.5 years, one, my wife, 38 😉 I rarely get time to learn how to use the equipment to actually cut stuff.

During a rare couple of hours free time, I decided to play about with GRBL

I figured I’d explain how I finally managed to get it going on my Arduino Duemilanove, with my Clone CNC Shield V4

Of course, as always, practically, nothing’s been done, the shield is sitting on the arduino, doing its shieldy stuff, there’s no motors or power connected, just a string of stuff coming out of the serial port! (so, it probably works, right?)

FIRST – use GOOGLE CHROME (wasted an hour on that one, couldn’t connect to JSON server!)

SECOND –  Download the pre-compiled HEX file – at the GRBL websit home page, scroll down a bit

Direct link – http://Grbl v0.9j Atmega328p 16mhz 115200baud with generic defaults (2015-07-17) (version 0.9J as of writing)

THIRD – Connect up your arduino and flash it with XLOADER – See instructions – HERE

Reset the Arduino

FOURTH – Download the JSON Serial server from Github – Home page Here

– unzip to somewhere nice (i’m on desktop!) and run the server, ensure to tick ‘allow firewall access

Note down which COM port your Arduino is connected to

FIFTH – Open up CHROME, type in http://localhost:8989

SIXTH – Type in the new window that appeared OPEN COM8 115200

(where COM8 is the com number of your serial / USB adaptor on the arduino)

Seventh – FIre up chillipeppr, Select GRBL

Voila, you’re talking, it all seems to automagically work!

Of course, there’ll be a way of automating  / adding a command line prompt to the JSON thingy so you don’t have to web into localhost first…..small steps eh!

On my travels, also discovered that it’s not trivial to get TinyG2 running on the Arduino Due – with the CNCshieldV4 that I Have  i’ve put that experiment off a little while

Next step, cutting stuff – ETA, 2016?

TinyG, TinyG V2, Arduinos

Gonna be slow few weeks….

Some researching on alternate control methods for the CNC, avoiding totally the old school parallel port…

Well, today the parts have arrived, I’ll be assembling them soon,

Looks like it’s Very early days for TinyG V2 and the CNC shields along with the Arduino Due..

However, good news it does seem.

TinyG V2 is compatible with the RAMPS-FD and modified RAMPS 3D printer boards…and another board I’ve just discovered  – GAUPS – HERE

Those devices use  the standard Polulu style driver modules – that use the A4988 Stepper Driver from Allegro MicroSystems

My CNC Shield V3 device also uses those devices.

So, fingers crossed, it should be, worst case a simple pin-reconfiguration, probably something I can do in some spare time here

Software!, Another!!!!, CAM thoughts

The Actual, Physical CNC’ing is on hold for a few weeks whilst family come down to visit.

So, doing waaaaay too much research, i’ve narrowed down some software selections,

Here’s some thoughts on the CAM, which’ll probably go out of the window as I’ve still not decided on which CAD software to start putting time into to learn.

this CNC stuff is 90% preparation, design, bugger about. Turns out the fun, actually making physical stuff is only 10%! D’oh!

CAM software – stuff wot makes the toolpaths, in order of pricing

  • http://www.grzsoftware.com/ – Meshcam
    • easy to use
    • well priced – $250 USD (around $340 AUD at time of writing)
    • great for 3D, not so good for 2D

Here’s some other peoples thoughts

http://www.factorydaily.com/node/1223089 – quick compare of 3 CAM softwares

http://blog.cnccookbook.com/2014/01/20/results-from-the-2014-cnccookbook-cam-software-market-share-survey/ – Survey showing top used CAM softawre – Meshcam top, followed by CAMBAM for the hobby market!

CAM2014LowEnd