SIEG X2 MINI MILL BELT DRIVE CONVERSION: My version with 220V 3 phase motor and VFD

Another project is finally finished: SIEG X2 aka MINI MILL BELT DRIVE CONVERSION.

The original SIEG X2 DC motor prematurely left me with a piece of junk, cause to carbon brushes spikes. I tried to change mosfet, but after another set, i decided to convert this machine to belt drive.

The new version uses a 750W motor (1HP) with a Mitsubishi VFD.
In the post, video of operation and make of. 

Finished belt conversion

The 3d printed test

Another view of 3d printed test

6 mm aluminium plate 

Too many chips... need to find a solution

Refining the two hubs... mmm... why not cnc

PCB CNC ABLATED WITH LASER: why send outside if you can do at home

A long waited fab for PCB, etched in house using a 5W visible laser (450nm), diy chemicals. The process is straightforwarding and really precise.

I started with black spray paint, then lasered with FlatCam and GRBL, then etched with hydrochloride (33%) and hydrogen peroxide (130 volumes, difficult to find).

Videos at the end of the post.

A great result: total time approximately 30 minutes.

Blank one side PCB

Tried two spray paint. The right one is the best, matte black acrylic paint

Just sprayed

Cutted and ready to be ablated with 5W laser

Ablation in progress (previous photo without support). Air assist is really necessary.

The 5W laser is ablating spray paint @ 100% duty cycle - feed: 700 mm/min, but i tried also 30% duty cycle and it worked. 

Ablated pc, design from kicad with FlatCam

Ablated pcb. Before etching, i cleaned it with peroxide @ 3%

Etching, only ten seconds

Before etching, I've heated @ 40 degrees Celsius

 

Etched and rinsed in tap cold water

Cleaned with acetone (nail solvent) to clean residual paint

Close Up

Cutted (by hand this time) and drilled with 0.9

Next steps: soldermask and white text and double sided pcb.

METAL CASTING: Backyard metal foundry, introduction

Time to start a new project, which involves extreme temperatures, molten metal, sublimating foam and more like this. 

My propane burner

Backyard metal foundry will enable me to melt metal scrap into useful drafted objects that could be later machined with precision.
Temperature achievable at home (up to 1200°C) enable to melt aluminium, brass, copper, bronze. Iron requires higher temperature and different techniques.

The receipt involves few elements:
- a liquid propane tank. Liquid Propane has various advantages in respect to traditional charcoal foundry: requires less space, because energy density is higher, so mre energy. Here you could find in local stores 30 liters propane tanks with standard attachment.

source Own Work - author Hustvedt

- a propane burner. There are various models you can build, with back air or with venturi effect. The one i decided to build is the simplest one. It attaches to propane tank with standard pressure reducer, then with a pipe attaches to a custom burner based on two elements, the burner itself which is a drilled steel water pipe of standard length and the gas diffuser, another steel pipe with tiny hole on the center. The gas flows from the tiny hole then mix with back air and blows a blue flame of high temperature. A possible add-on may be a back air blower to enhance the oxygen available to complete the combustion inside the foundry.
Note the burner itself has specific dimensions and more air holes to capture oxygen.

- a foundry. This is where the burned gas inside a refractory lining fuse the scrape metal. The construction of the foundry is more or less a metal barrel with refractory cement on the bottom and on the walls. A removable cement top hat with hole, to regulate the heat into the chamber, complete the foundry.
For my application i found a convenient olive oil barrel that I cutted with grinder. On the side, near the bottom, I will drill an hole with specific angle to introduce the burner.

- the crucible. for hobby metal needs simple steel barrel is sufficient. For more specific application sintered crucibles made from ceramic or oxide powder is required because molten metal (Specifically aluminium react with iron). And more could be easily replaced.

- a flask with sand and cavity or, in my case, foam. Foam metal casting is a recent technique in which a foam pattern remain inside the sand. The molten metal replaces instantaneous the foam sublimating it. After cooling the foam is no more present and the metal has the design of the foam pattern.
Find more information on this process on wikipedia.
Of course the best site around from 2000: http://www.backyardmetalcasting.com/

- the pattern, that could be easily machined with cnc or standard technology.

OUTSIDE: KUROKESU - how passion can drive your life

As I noticed KUROKESU range of product, i wanted to deep dive on the philosophy guiding this lithuanian guy and his team. What I learned so far is that your passion can lead your life to new dimension.

About KUROKESU you can read in his website

"What started as a great way to burn my free-time has evolved into a full-time occupation – but from the start Kurokesu has been my passion. Initially I made all the parts and assembled every product myself, from USB cameras and lenses through to precision tools and motion systems. [...] At the end of spring 2017 I was able to quit my day job."

While you can find a machine probe from aliexpress, I would prefer 100:1 to acquire it from this source, to support his business, and also because the quality of his products could be measured just by by design details.

In the E-store you can find a fine motorized rotary stage:

A sturdy Raspberry PI enclosure (note the actual revision is F):

A complete USB camera with C-Mount lens (for instance to assembly a soldering or inspection macro camera):

A logitech c920 rework case:

What I like so much, is the touch probe:

I will give a try to the touch probe soon.

Good luck KUROKESU.

All credits for the photos belongs to him.