Tag Archives: GAUPS

Enclosure for my Arduino and GAUPS

Finishing my ShapeOko rebuild

As the last thing on my to-do list I’ve build an enclosure (or box if you will) for my Arduino and GAUPS shield for my ShapeOko so that it will get out of harms way. Please see this post for an explanation.

I decided to make the enclosure from 10 mm plywood and add two improvements to the electronics: a 24V 60 mm fan to keep the GAUPS shield cool and a kill switch to be able cut the power for the stepper motors.

The result looks like this:

Arduino enclosure.

Arduino enclosure.

Arduino enclosure - other view.

Arduino enclosure – other view.

If you’re interested the dxf-file for the enclosure can be downloaded on my woodworking plans page. I milled a 2mm recess for the Arduino in the bottom of the enclosure so the Arduino would fit without the solderings on the bottom of the Arduino will touch the bottom of the enclosure (see the dxf-file).

Rebuilding my ShapeOko 2 – part 3

If you missed part 2, please find it here.

Finishing the frame

Now I’ve finished the frame, mounted the z-axis gantry and rewired all the stepper motors. It starts to look like a ShapeOko again. 🙂

Z-axis gantry mounted.

Z-axis gantry mounted.

A first test run

My new GAUPS shield has an extra slot for a stepper motor driver which allows for running a dual y operation on separate stepper motor drivers. I didn’t really plan to change the setup I had (running two stepper motors on one driver) but since I’m rebuilding everything, I decided to take the opportunity to try using both drivers for dual y operation.

After connecting everything and switch some wires to make the stepper motors run in the correct direction, I was ready to give it a try:

 

In the video above I’m moving the machine 800 mm on the x-axis, 300 mm on the y-axis and 25 mm on the z-axis just to test that I actually have the working area I expected. 🙂

My new gaups shield – part 2

If you missed part 1 please find it here.

My new shield is ready

Finally my stepper motor drivers arrived and I’m ready to move on. I’ve placed them in their sockets and have adjusted the drivers according to this procedure.

Arduino with GAUPS shield and stepper motor drivers.

Arduino with GAUPS shield and stepper motor drivers.

Unfortunately I’m not ready to go because my Kress 800 FME spindle is broken. 🙁

I suspect that the carbon brushes are worn out but I’ve returned it to the reseller so we shall see what happens…

Another rebuild for my ShapeOko 2

Rebuilding the whole thing

As you might have seen in this post, my grbl shield is broken and I’m in the process of replacing it with a gaups shield from ASL. When my new shield is assembled it is my plan to build some sort of casing for it (mostly for protection). Furthermore, I’ve decided to make my ShapeOko 2 larger so I’ve ordered some new parts for it (longer MakerSlides among other things). I then realized that my dust collecting cyclone (made by a friend of mine) has to be remade as well to support the larger ShapeOko 2 in my workshop and to get it out of the way, when I use the ShapeOko. Any project has a tendency to grow on it’s own… 🙂

Cyclone

My old cyclone has been working very well so I’m not going to discard the basic idea: My friend who is a chemical engineer discovered that an empty bottle from a particular brand of soft drink has a cone shape, that fits the theory behind a cyclone very well (actually nearly perfect). Furthermore, it’s my plan to mount it on the wall and use pipes to get the dust collection where I need it, so I went looking for pipes that will fit the hose on my vacuum cleaner. As it turned out a 32 mm plastic pipe fits perfectly.

Bottle and plastic pipe.

Bottle and plastic pipe.

The theory of cyclones

I’m not an expert in cyclones so I went looking for information about cyclones on the Internet and Thayer School of Engineering at Dartmouth turned out to have a pdf from a course on their homepage, that explains everything very well. Especially the drawing below was helpful:

Standard cyclone dimensions

Standard cyclone dimensions.

Calculations

Since the cyclone diameter D, the dust outlet diameter Dd, the gas outlet diameter De and the cone length Lc all are defined either by my bottle or by the vacuum cleaner hose, the remaining calculations are easy. The values measured on my bottle are:

  • D = 75 mm
  • Dd = 26 mm
  • Dc = 29 mm
  • Lc = 160 mm

This gives the following values:

  • D/D = 1
  • De /D = 0,39
  • Dd /D = 0,35
  • Lc /D = 2,13

These values lies somewhere between (2) and (3) in the standard cyclone dimensions, so I decided to aim at a cyclone with dimensions as an average of the values of (2) and (3). I know it won’t be perfect but hopefully it will work just fine. My calculations are:

Cyclone calculations

Cyclone calculations.

Drawing in OpenSCAD

Then it’s time to make a drawing in OpenSCAD (I love that program). The drawing below is what will become the inside of my new cyclone. Here is the OpenSCAD file: Cyclone and the STL files.

It looks like this:

Cyclone in OpenSCAD

Cyclone in OpenSCAD.

The cone itself and part of the body is made out of my bottle and the top will be milled in wood on my ShapeOko. The top will be four slices 20 mm thick: One with a 32 mm hole for the vacuum cleaner hose, one with a 80 mm (the outer diameter of my bottle) hole holding the bottle and two pieces that glued together will form the inlet. The last two parts look like this:

 

Inlet top part.

Inlet top part (upside down).

Inlet bottom part.

Inlet bottom part.

Milling the parts

I used ArtCAM Express to generate the g-code for milling the parts. The finished result is here:

The four pieces for the cyclone inlet part.

The four pieces for the cyclone inlet part.

Stacked on top of each other.

Stacked on top of each other.

Notice that the inner diameter of the cyclone is 75 mm and the fourth piece has an 80 mm recess for holding the bottle. Furthermore, my calculations above suggested that the value of Lb should be 128 mm but the height of the inlet is about 40 mm, so I cut my bottle at 88 mm from the top of the cone in order to make the entire height 128 mm.

More will follow… 🙂

Part 2.

My new gaups shield

My new shield has arrived

Some time ago my g-shield broke (see this post) and I ordered a new gaups shield from ASL which arrived last week. It’s a kit so some skills in soldering is required (I’m not very good at it) but never the less assembly is quite easy when you follow the instructions.

When soldering the female headers for the drivers onto the pcb I remembered a trick I saw somewhere on the Internet: Use the Arduino stacking headers to hold the female headers in place until they’re attached to the pcb:

Holding the female headers in place using the Arduino stacking headers.

Holding the female headers in place using the Arduino stacking headers.

The distance between the female headers matches the distance between six pins on the stacking headers. So I arranged the headers as seen in the photo and turned the whole thing upside down and started soldering:

The pcb resting on top of the stacking headers.

The pcb resting on top of the stacking headers before soldering the female headers in place.

Here is the finished gaups shield on top of an Arduino:

Gaups shield on top of my Arduino.

Gaups shield on top of my Arduino.

Now I’m just waiting for my Pololu drivers to arrive… 🙂

Part 2.