Pre-raquisite Software Skill for operating the BEAST

Building the CNC Router was a stressful but fulfilling experience. Inflated ego was the direct product of this memorable journey. BUT that is only the starting line of my CNC endeavour. Now that I have a machine at my disposal, I need to learn up how to drive this machine to churn out those beautiful artifact like we seen in the net.


In retrospect, running the machine is easy, but that is only after you actually operate the machine...

I totally over estimated my learning capacity, & underestimated the complexity of the software involvement in running a CNC machine. After over a month of tinkering with running the machine & many software packages, I come to this overly generalised summery.
You need a Drawing to convert to G-code, feed the G-code to the Motion Controller. To cut properly, one need to know the cutting tool characteristics, material properties & some machining procedure knowledge.


Drawings
To make something with or without CNC machines, we need to provide specific specifications of what to do, so coming up with a drawing is the first step.
From my understanding, we can use 2 types of drawing files, namely Raster & Vector.
In raster, examples are bitmap such as jpg, png etc. With this, the cutter will transverse the whole area covered by the file, this is how most 3D cutting is done. With Vector file, the cutter only travels along the path where the cutting is required, saving lots of time. this is how profile cutting & 2.5D are done.


Drawing software
With different cutting strategies different software are used. In vector files, we direct the cutter in straight lines to cut the profile or contours, leaving the other space alone. In raster file, the cutter will transverse every mm of the file... example of raster files are bitmap. & the generally accepted vector file format is .DXF, other formats are SVG, AI, STL... etc etc
I'm fortunate enough to have worked with AutoCad in my junior career life & residue memory helps a lot when relearning. This is my preference for 2D & 3D rendering but there are others such as SolidWorks. You can also use CoralDraw, Win Paint, Adobe Inventor, SketchUp Pro,.... Open source CAD drawing are not quite up to the fee software but I find Blender is a promising, still crude but its getting somewhere.
I also learn that one doesn't need to draw a drawing from scratch everytime, especially when we are dealing with ornamental & art craft... We can "convert" raster files to vector files by tracing bitmap. I downloaded the open source INKSCAPE software which can do many capabilities of fee software such as the Coraldraw & Adobe AI.

G-code
One can write G-code from scratch if they feel they are up to it, BUT I'm too lazy for that... CAMBAM, UCANCAM, SHEETCAM, LAZYCAM... a whole library of CAM software which can translate vector file into G-code. I evenetually ended up with VCarve Pro for 2D & 2.5D works & Cut3D for 3D works..

At the end of the day, depending on requirement, all common or not so common software packages works, the difference are in the learning curve & the ingenuity of the user to utilise the available capabilities of each. Its a compromise of $, time & requirement.

Z-Axis Concoction

You might notice there isn't much mentioned on the Z-axis.

I did my own "design" to cure my needs to have my own signature in this machine.

Using Linear Slide & Rail bar is more expensive, but it does give peace to my mind & fulfill my over-sized ego...

There you have it.
All Axis are assemble (almost)...
The last piece of purchase to get this to machine to work will be the Gas Spring & a 500mm long gear rack.

Paint Job

After some back breaking working with steel, All the steel (at least what I know is requires) are cut, drilled, taped, ground, de-burred and painted.

This is the hardest part of the whole build as I have to lift serious weight, endure flying sparks, deafening power tools noise, work in dust filled environment, work on my knees, squatting for long hours & drinking 3 litter of water each day for over 2 weeks...

My advise, get a helper....

The dust is intensive, I lost count after I swept up two 50 liter buckets of grind steel dust...

I then decided to paint the steel before welding to avoid the intensive Yoga exercise session if I were to paint the table after the table is completely welded... Can always repair the scratches & welding burnt paint with a tat to extra paint...

Painting is a PITA task, easy to do but takes ages to reach a competent level of finishing...

How much PITA? Before you paint, one has to prepare the steel...

• Firstly, you have to remove loose scale & rust with grade A60 sand paper or power brush with an angle grinder, 
• Secondly, you have to rub down the dust & any oil stain from the surface with solvent, I use patrol for this task as they are great solvent that are easily available & they will evaporate without a trace. There are other practices such as wahing the steel with light detergent but I alway prefer how I did it...

• Then you get to paint...

Now, you can op for spray painting or hand painting... as my body is all sore after the earlier works, I hate to haul all the steel into the open & haul them back to the workshop after they are done... AND its raining season... a bad bad thing for wet or half dried paint...

*ps, It did rain a few time (per day) during the 3 day span of my paint job.

I use 4" paint roller for the job, some how, I can't paint with normal paint brush & roller saves me from the emberresment. AND with rollers, it is easy to control paint thickness & produce a even matted finishing which I like.

My paint selection :- 1 coat of Red Oxide primer & 2 coat of Enemal Alkyd paint (commonly know as Glossy paint).

More painting PITA....

1. Apply the 1st primer coat after the patrol had evaporated & squeaky clean...
2. Wait...... 4~6 hours for the primer to cure enough for the top coat... Too short the curing then the primer will be too wet for the top coat, too long the primer will harden too much for the top coat to "bite" on to the primer coat...
3. Apply the 1st coat, do not brush over the same spot over & over again, this will make the top coat to mix with the primer coat... Nevermind if you can still see the tint colour of the primer coat on this 1st top coat, you can get this corrected with the 2nd coat.
4. Wait..... read the instruction on the paint can, it says 4 hour for touch dry & 6~8 hour to re coat.... I waited 8 hours & they still feel too tacky for the second coat so I left them over night to cure properly...
5. The 2nd coat will be a breeze as you had already 2 coat of practice & finish in no time.

This is what I got

 The laser cut profiles.

The table parts including the rails in black

The table bearer channels 1 1/2 x 3" channels

Close up of the main 3" x 8" channel

The table leg & supporting tube trusses

Not forgetting the rails, with 2 coat of smooth black Hammerite paint...

Progress

The special feature of this MechMate is that one could choose to make their own precision rail guide which are not short in quality in comparison to off the shelf guide rails. With some simple tools, a lot of patient, enduring loud grinding machine noise, & 2 weeks of back breaking work, I eventually completed the rail guides.

The whole lot

A closer view

View from another angle

This is the first milestone of this build & I hope there rest of the build will be less laborous & demanding.

DIY CNC Router

There are many approach to own a CNC machine, you can buy one of those industrial CNC machine center or you can build one with recycling printer stepper motors, some bearings and guides.... For me, I'll skip the baby toys and jump straight to building a Mechmate; A full fledged real McCoy CNC router. Like this one here.


This beautiful design is the work of Gerald. D, he generously give away his design for free and will provide selfless support from his forum. Thumbs up to Gerald.

Why not design myself? Surely I can, if I spend the next 10 years on it... And since this thing isn't going to be cheap to build, I might as well take the "safe" path and get it to work as-soon-as-possible.

I will build one that can take in a full size 4' x 8' sheet. wood based material such as plywood, MDF, chipboard.. etc. Soft metal such as aluminum, bronze, copper. Plastics such as Teflon, Darline, acrylic, prospect, polycarbonate... etc

My Spec.
working size : 2440mm x 1220 (8' by 4')
Tool head : 2.2kw Water Cooled Inverter Controlled High Speed Spindle head.
Drive Motor : NEMA 34 stepper motor
Motion Control : PC based
Precision : +/- 0.01mm

Had been spending like no tomorrow for the past month and the spending never stops....

I am scheduled to start construction by end September or early October....

Wise me luck...