AUS DEM LEBEN EINES HARDWARE- STARTUPS

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Eine kleine Fräse auf Reise: Reisevorbereitungen

Als Gründer eines Startups muss man sich mit vielen verschiedenen Fragen beschäftigen:

  • Was ist meine Idee, und wie setze ich diese am besten in ein Produkt um?
  • Wie baue ich mein Team auf, um mir bei der Entwicklung des Unternehmens zu helfen?
  • Wie kann ich mein Unternehmen finanzieren?
  • Welche (patent-)rechtlichen Probleme kann ich mit meinem Startup haben?
  • Wie bekomme ich mein Produkt zu meinen Kunden?

All das sind Fragen die wir uns als Gründerteam immer wieder gestellt haben. Am Anfang stand die Idee zu einer Desktop-CNC Fräse, und ein Prototyp war schnell gebaut. Wenn man die ersten Probleme gelöst hat kommen wieder neue, unvorhergesehen Probleme.

Manche sind einfach zu lösen, andere brauchen Zeit, und oft auch Geld, welches bei einem Startup immer knapp ist.

Während der Entwicklung muss man sich Gedanken über grundlegende Dinge machen wie zum Beispiel:

  • Wer ist meine Zielgruppe?
  • Welcher Preis ist für mein Produkt angemessen?
  • Welche Features werden von unseren Kunden gewünscht?
  • Welche Größe und Gewicht sind für mein Produkt praktisch?

Um die letzte dieser Fragen zu beantworten haben wir uns unter anderem darüber Gedanken gemacht, wie man den Versand günstig und sicher abwickeln kann. Dazu haben wir uns an den Richtlinien der österreichischen Post orientiert.

Als oberösterreichisches Startup sind wir mit der Post vertraut, und waren der Meinung mit dieser einen guten Partner für unser wachsendes Unternehmen zu haben, nicht zuletzt aufgrund des Werbespruchs:

„Wenn‘s wirklich wichtig ist, dann lieber mit der Post.“

Die letzte MINImill haben wir Ende Jänner nach Bozen verkauft. Da die MINImill aus einem 1.5mm Stahlrahmen, sowie einem Gehäuse aus 3mm Aluminium-Dibond besteht weißt sie von vornherein eine sehr hohe Stabilität auf, und bis jetzt hatten wir noch mit keinem unserer Versuchs- und Vorführmodelle Probleme wegen der Stabilität, auch nach sehr rauer Behandlung.

Um auf Nummer Sicher zu gehen haben wir uns für den Versand für verstärkte Kartons mit einer Tragfähigkeit bis 40kg entschieden (die MINImill wiegt 22kg), und alle Ecken, sowie die stärker belasteten Kanten an der Unterseite mit Schaumstoffecken geschützt.

Welche weiteren Vorkehrungen zum sicheren Versand von uns getroffen wurden, und wie die weitere Reise verlief werden wir in den nächsten Tagen hier veröffentlichen.

PCB Milling Tutorial

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This tutorial will guide you through the milling process of single sided PCBs

You can use the example files from our download site, or use our EAGLE CAM-Job to create the Gerberfiles for your own project.

Example project: LED Backlight

Open the MINImill Software

Connect your qBot MINImill and press the Unlock button. Your MINImill will start homing.

Open the PCB Tab

Open the PCB Tab of the software, by clicking onto the “PCB” Symbol in the bottom toolbar. On the right side you can open the gerber files for top, bottom, drill and outline.

If you want to use the Gerber- files used in this Tutorial, you can download them at the first step.

You should generate the Gerber-files according to this list, or just download the preconfigured CAM-Job (EAGLE-only at the moment)

Top: Top-layer traces, Vias, top-SMD-pads, Through hole-pads
Bottom: Bottom-layer-traces, Vias, bottom-SMD-pads, Through hole-pads
Drill (Excellon): Drills, Holes, Pads, Vias
Outline: Dimension, Milling

The outline must have a width >0mm, and must to be one closed shape. Milling-features inside the outline are ignored, only the outermost one is being milled.

Open your gerber files

Click on the files and open them accordingly (For the Top Layout – open the Top Layout Gerber file, for the Drill Layout- open the Drill Gerber file, for the Outline Layout – open the Outline Gerber file).

Note: If you are milling single sided PCBs, don’t open a bottom file.

The progress-bars indicate the success of your conversion process.

Grey: no file loaded
Yellow: Conversion active
Green: Conversion successful
Red: Error

Note: If you drew your single-sided board in the bottom-layer, just load the bottom file into the top layer and leave the bottom empty

Place your file on the PCB

Click on the part and drag it until it is within the PCB (use the left mouse button to drag, the mouse wheel to zoom and the right mouse button to turn your work table), and where you want it to be milled – be careful that the whole part is within the cooper-colored PCB, and that you leave enough space near the screws and the border.

Mount the PCB milling bracket

Mount the PCB-bracket, remove the protective film of the PCB and place the PCB on the provided space.

Insert the Engraving Bit

Press the play button to start the milling process – a text box will open which asks you to insert the correct tool.

Insert the engraving bit into the collet, so that it protrudes around 20mm from the collet. Use the 13mm and 17mm wrenches that are provided with your MINImill to tighten the collet nut. Be careful not to overtighten the nut!

Remove the protective sleeve after you have inserted the engraving bit into the collet. This way the bit will not be damaged if you accidentally drop it.

After inserting the engraving bit – confirm the tool change message.

The engraving process

After pressing confirm – press PLAY to start the engraving process.

After you press PLAY MINImill will start to measure the toollength, and probe the surface of the PCB.

The heightmap generated during this step is used to make a virtual image of the PCB in your MINImill, which is then used to recalculate the GCode and make everything perfectly flat. Do not touch the PCB after the probing is done or the height could change, and lead to not perfectly milled PCBs!

After the measuring procedure is done, MINImill will start the milling cycle automatically.

Change to the drilling bit

The MINImill software will pop up a window, asking you to change the engraving bit to the right drill. The procedure is the same as for inserting the Engraving bit. Again, pay attention how firmly you tighten the collet nut.

You’ll notice when you go to take tools out that there is a tight/loose/tight/loose again torque response as you unscrew the nut, as the collet “sticks” a bit to the tool. The tool is still fairly tightly held until you pass that second sticking spot. Once you get past that, the tool will fall right out, so be ready to catch it!

Confirm the tool change message to get to the next step.

The drilling process

Confirm the tool change message and press PLAY to start the drilling process.

MINImill will measure the length of the tool, and automatically drill all holes. If a drill with a different size is needed you will be asked to change the drill to the new one.

Note: The size is displayed in inch or mm, depending on the settings of your CAD-program.

Change the drill bit to the outline bit

You will be asked to change the drill bit to the outline bit (2mm endmill, suited for hard plastics).

The procedure is the same as described above, after pressing confirm and play, MINImill will measure the toollength, and automatically start the milling process.

The outline milling process

After pressing confirm and PLAY MINImill will start with the outline milling process.

You do not need to take any actions here. MINImill will do several passes, until the part is finally cut out, and ready to be used.

Use a vacuum cleaner to clean away the dust, and be careful not to suck in your part. If the edges of the part and the traces are a bit rough you can use wet sandpaper (1200 grit and above) to sand them down. For this, lay down the sandpaper on a flat surface, wet it with some water, put the PCB on the sandpaper with the traces down and use circling motions to sand the edges down. You don’t need a lot of pressure for this, and you should also not do this for to long, as not to sand away the trace. Be careful not to overdo it.

The finished part

When you are happy with the finished part you can use some industrial alcohol to clean away any oxide (this is not necessary if you used PCBs with a protective film).

We would be happy to receive pictures of your finished parts for our instagram site!

Happy milling!

tech specs

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MINImill

The qBot MINImill is supplied with the following parts:

A PCB-milling starter kit, containing: a PCB bracket, a basic PCB milling bundle, some PCBs, so you can get started right away.

Two wrenches for locking the collet nut, a manual explaining how to get the most out of your MINImill

Dimensions

Mail

Machine size: 400x400x400mm

Work table: 260x160mm

Work area: 175x150x65mm

The worktable is made of industry-grade aluminum, giving you a great surface to fix your project to, while being almost perfectly flat.

You can use standard t-nuts (size 8), which -of course- are included with the MINImill- to fix your projects to the worktable. MINImill also offers some M4 screw points, which are firmly connected to the worktable, to give you an even better experience, and more security. They also offer a unique way of electrically connecting your project to the MINImill, and enable you to measure the surface of conductive materials.

Spindle

200W DC spindle with 12000rpm

ER 11 collet, 3.175mm collet

The high-power, 200W spindle motor has enough power to mill through a wide range of materials, even when you use a bigger endmill. The Spindle has a very low runout, which is essential if you want to mill very precise parts, and to ensure that small endmills and drills (< 0.5mm) do not break during operation.

Materials

The qBot MINImill is made and tested for a wide variety of materials:

Wood, for nice looking gadgets and enclosures

Plastics, for more functional parts

Acrylic, for transparent or translucent projects

Modelling-foam, in different strenghts, depending on what you want to make. From casting, to vacuumforming and even aluminum-forming, all the forms you need can be made with the highest precision on a MINImill.

Circuit boards (FR1, FR2, FR3), to make development of new products eaysier and a lot faster, MINImill is capable of milling single- and doublesided layouts down to small SMT-devices like 0603 resistors

If you need inspiration, or just want to check out projects that other people have already made check out our Instagram-page.

Axes

1204 ball screw with direct drive

hardened 16mm steel shafts with linear ball bearings

up to 2500mm/min

The MINImill uses direct-drive for all axes, thus ensuring the highest positioning accuracy. The hardened 16mm steel shafts provide ample stability. The sturdy frame, consisting of aluminum-compound and automotive-grade steel keeps everything in place, and reduces noise and vibrations to a minimum. This was a high priority for us during development, so the MInimill would be silent enough so it can be used in an office- environment.

Precision

Repeatability: approx. 1/100mm

Motor resolution: 0.00125mm/step

Workarea flatness: +-0.1mm or 0.1 ‰

The numbers above specify some real-life- specifications that we have measured on a different MINImill, in different environments.

Of course it always depends on how you set up the MINImill. If you have difficulties imagining what these numbers mean for your specific usecase, just ask us. We are always glad if we can help, and communication with our customers is very important for us.

Electronics

MINImill uses an Arduino Uno with the awesome “GRBL” open-source machine controller

The 350W internal power supply can be used in 230v and 110V systems, so the MINImill can be used not only in one country, but everywhere!

MINImill is safe to use. The main-power switch disconnects it from the grid, and the fuses protect it in case of a failure.

Software

We recommend our free MINImill Software, which includes a Slicer for PCB (.gerber) and 2D/3D files (.dxf, .stl).

However as our MINImill runs on GRBL it can be controlled by any GCODE sender which works with GRBL. Just check out their GitHub-page, they have some recommendations there.

Price: 3990€ VAT included, Machine currently available in Austria.

MINImill got featured on Tuvie!

MINImill got featured on Tuvie!

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One of our favorite Design-blogs, Tuvie featured the MINImill!

It is now standing among the worlds most exciting and futuristic designs.

We are very excited about this great possibility to let more people know about the concept of small desktop-cnc machines and the awesome software interface.

Check out the article on their site:

www.tuvie.com/minimill

Reviving an iPhone 5C with a dead charging port

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Caution: Do not attempt this with your functioning iPhone 5C!

An iPhone 5C with a defect charging port has been revived with an added Micro USB Charging Module (1A charging current) and a Li-ion Battery (size: 18650, 3100mAh – double the size of the original battery). The original charging port, the battery and the loudspeaker have been removed to provide ample space for our new features.

Revived Iphone 5C

Step 1: CNC milling the accu cut out on a MINImill

After disassembling the iPhone 5C, we milled a 65.5×14.5mm slot on a MINImill into the backplate of the iPhone to accomodate the 18650 battery. We wrapped the electronic circuit board in plastic to prevent milling dust from getting inside the sensitive electronic circuit board. Milling the Steel- Polycarbonate Backplate on the MINImill worked great, although Apple obviously used very high quality materials.

Iphone 5C placed in a MINImill

Step 2: Wiring the electronics and glueing them into place

The next step after making room for the new battery was glueing everything in place, connnecting the charging-module with the battery and the USB-Port and connecting the iPhone power supply port (the battery connector pin on the main board) in parallel with the new battery. After sucessfully testing the iPhone, we started reassembling it.

Iphone 5C - Sideview

Step 3: Iphone is ready to rumble

The iPhone booted without any problems, and we were able to close it again. We now have a fully working iPhone with a battery twice the capacity of the original one. Also the cost for the repair was below 10€, so for us it was, thanks to the capabilities of the MINImill a great way to fix our phone.

Iphone 5C - Running with 18650