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Here are the results and a key for the detail test that I had printed by Shapeways in stainless steel. The detail is quite remarkable. If this interests you, check out the 3D Printed Metric Hole Test Pattern and Key.

First the scale, compared to a penny:

Detail Test Scale

Detail Test Scale

This is the key in case you want to try to print these yourself in different materials. Click for a larger view.

Detail Test Key

Detail Test Key

And finally the front and back. Click for larger views.

Detail Test Side 1

Detail Test Side 1

Detail Test Side 2

Detail Test Side 2

I have a Synology DiskStation (DS209j) that I use on a primarily Windows network, but in some cases I want to access the DS shares from Ubuntu virtual machine running inside VirtualBox. There’s no sense mounting them as Windows shares with the DS supports NFS, so I went that route in stead. (Besides, some application still have trouble with Samba shares.)

I was scratching my head over a “access denied by server while mounting” error until I realized that VirtualBox was getting in the way. Here are the steps I took to get it up and running properly:

  1. In the VirtualBox menu of the virtual machine , select Devices > Network Adapters… and choose Bridge Adapter instead of the default NAT. This takes your virtual machine out of the private network it has with the host computer and makes it a first-class citizen on the network your host computer is on, with its own IP address.
  2. Check the guest machine’s IP address by opening Applications > Accessories > Terminal and typing “ipconfig”. It will probably start with “192.168″, but you’ll need all four parts if you want to limit access to just that machine.
  3. Log into Synology DiskStation Manager as admin, and click Management.
    1. Under Information, click Status and note the network IP address of your DiskStation. It will probably start with “192.168″, but you’ll need all four parts of the IP address.
    2. Under File Sharing, click NFS, and make sure it’s enabled.
    3. Under Privileges, click Shared Folder. Select the folder one you want to mount using NFS, and click NFS Privileges at the top of the list to add a new privilege. Use the IP address of the guess machine to lock access down to that specific machine, or use wildcards to allow access accross your local network (e.g. “192.168.*.*”).
    4. Before you close the NFS Privileges window, note the “Mount path” at the bottom of the list. It will probably look something like “/volume1/MyShare”
  4. To automatically mount the NFS share when you start up, go back to the Terminal window on the guest machine.
    1. Create a directory to use as a mount location. For example if you want to use “MyDSData” in your home folder, type “sudo mkdir /home/YourUserName/MyDSData”. Enter your password when prompted.
    2. Type “sudo gedit /etc/fstab” in the same Terminal window, and edit then add the line below  line to the end of the file. (It’s all one line.) Instead of “[DS IP Address]” use the IP address of your Synology DS, instead of “[Mount path]” type the mount pah, and instead of [Mount location] type the directory you made above. Don’t leave out the colon or the spaces.

      [DS IP Address]:[Mount path] [Mount location] nfs rw,hard,intr,nolock,nfsvers=3 0 0

      For example: “192.168.1.42:/volume1/MyShare /home/alex/MyDDData nfs rw,hard,intr,nolock,nfsvers=3 0 0″

I had some trouble getting my HP LaserJet P1006 to work with the Synology DS206j (NAS print server), even though HP makes Linux drivers and other Synology DiskStation users have had success. The documents would look like they were sent to the printer just fine, but then nothing would happen — nothing actually printed.

The answer came in a recent Synology forum post by a user named efex. There are just a couple of points I’ll make, then just follow his instructions. These both come up in Step 9 of efex’s tutorial:

  • For the LaserJet P1006 specifically, the “$PRODUCT” value is “3f0/3e17/100″.
  • To save the file back to the share, you may need to clear read-only o archive file attributes. In Windows, right-click on the file name located on the share, choose Properties, and then and uncheck those file attributes.

See the whole tutorial, along with links for other product codes, visit this forum post.

Below is the key for the Metric Hole Test Pattern object, which is available at Shapeways.com. It is a flat, 3 millimeter thick piece with standard metric drill bit size holes, and can be used just as a decoration, or to measure detail, accuracy, and distortion (holes and flatness) in printed materials. It’s also useful for judging the printed sizes of clearance or tap holes, or choosing a hole size to match a part you already have.

Holes range in size from 1mm to 3mm in 0.1mm steps, and from 3mm to 10mm in both 0.1mm steps and 0.25mm steps.

Shapeways Printable Metric Hole Test Pattern

Shapeways Printable Metric Hole Test Pattern

The holes organized in “rows” and placed as efficiently as possible in order to limit material use. This results in a unique and beautiful shape. There are also small bumps on the edges to indicate the odd (x.25 and x.75) measurements. It is 3mm thick so that it can be printed with a variety of materials, including stainless steel.

Shapeways Printable Metric Hole Test Pattern

Shapeways Printable Metric Hole Test Pattern

It was a bit of a challenge figuring out the ideal hole placements…

I ran across this ad for Lufthansa today at Die Welt. It got my attention — the whole web page fell off the screen. I almost wish I’d caught it while the content on the site still matched the image.

When I started using Blender again recently with Vista, I noticed that when I launched it I would only get a blank (black) screen. The command window screen was black, of course, but at least it reported “Checking for installed Python… got it!” The problem was that the main Blender window was blank.

It will work again if you switch from “Highest (32-bit)” color to “Medium (16 bit)” in Control Panel > Appearance and Personalization > Personalization > Display Settings, but that doesn’t make for good rendering. Instead just turn off the Windows Aero color scheme.

How to Turn Off the Windows Aero Color Scheme

They say Windows Aero doesn’t slow anything down on your machine, but if you can’t use the tools you need, you might need to disable it. Here’s how:

In Control Panel > Appearance and Personalization > Personalization > Window Color and Appearance, select a Color Scheme other than Windows Aero, them make sure you’re using “Highest (32-bit)” color in Control Panel > Appearance and Personalization > Personalization > Display Settings. You’ll lose the fancy transparent chrome effects, but you’ll be able to use Blender again.

First, create a shared folder using the VirtualBox user interface. For this example, we’ll call it “Data”. Launch Ubuntu.

From within Ubuntu, launch Application > Accessories > Terminal, and at the prompt type

sudo gedit /etc/fstab

Enter your administrative password, and you’ll see a text editor window appear with the fstab file loaded. Add the following single line to the end of the file, but replace “username” with your actual username.

Data /home/username/MyData vboxsf defaults,rw,uid=1000,gid=1000 0 0

Click “Save” and then restart Ubuntu.

Once restarted, go to Places > Home Folder and note the new MyData folder. This is your shared fol

In the A $6 Custom Branding Iron post, I showed off a branding iron I had “printed” in stainless steel by Shapeways.com for US$6, after using the free vector image editor Inkscape, and parametric modeling software Alibre Design, which also has a free version called Alibre Design Xpress.

This tutorial requires a working knowledge of Alibre Design (or other 3D parametric modeling software) and Inkscape (or other vector graphics editing software).

$6 branding iron

$6 branding iron

Here are the steps I took to make it happen: (I’ll add more detail over time.)

  • Design in Inkscape
    1. Convert all text objects to paths (Path > Object to path)
    2. Convert all stroked lines to paths (Path > Stroke to path)
    3. Ungroup all objects
    4. Union all objects (Path > Union)
    5. Select object
    6. Save As… Type Desktop Cutting Plotter (R13) (*.dfx) – Output will be in mm
  • Import into Alibre Design (File > Import, type DXF)
    1. Select mm for file units
    2. (It imports into a drawing)
    3. Select everything and Explode (Edit > Explode Symbol)
    4. Activate the sketch
    5. Analyze (Sketch > Analyze…)
    6. Heal all problems
    7. While activated, select the figures
  • Copy to a Alibre Design Part
    1. Open a new part
    2. Activate a design plane and Paste (the figure may appear far from center)
    3. Select the curves, shift-left-click to drag to better location
  • Model the branding iron
    1. Extrude sketch 1.25mm — this is the depth of the brand.
    2. Select *top* face and insert a plane. (right-click > Insert Plane…)
    3. Select the new plane, Project to Sketch (if necessary), to create a foundation for the brand.
    4. Extrude 2mm for foundation
    5. Insert another plane on the back of the foundation
    6. Extrude a mounting hole, 4.9mm is 0.1375mm larger than 3/16″
    7. Cut a set screw hole in an accessible location if necessary. 3.048mm is 0.12″, the tap size for #6-40 set screw.
  • Export & Upload
    1. Export as *.STL file
    2. Upload to Shapeways.com
    3. Order in stainless steel
  • Finish
    1. Tap the mounting flange for a 10-32 screw
    2. Thread a 3/8″ steel rod with 10-32 die or use a 10-32 screw
    3. Build a handle
    4. Sand down the surface of the branding iron to make it nice and flat

Some woodworkers like to leave their mark on their work using a branding iron, but at roughly $190 per iron, it can really be quite an investment. I took a less expensive route, using some free software, and a genius 3D printing service  called Shapeways.com.

I started by drawing up a couple of logo ideas in Inkscape, a free vector graphics application. I exported by design from Inkscape and imported it into Alibre Design, which is a fantastic parametric 3D modeling application that happens to be available for free in a feature-limited version. Once I was satisfied with the 3D model, I exported again, uploaded the file to Shapeways, and “printed” it in stainless steel. The total cost for the “AF” design was $6, and only $7.40 for the larger name logo.

I tapped the back of the iron and threaded a short section of 3/16″ steel rod, and inserted it into a little handle that I turned out of some scrap cherry. After a couple of test burns, I was pretty happy with the result. Next I’ll try sanding it down a bit to see if I can make it even cleaner.

Update: I’ve added a step-by-step tutorial on how I made these: Making the $6 Branding Iron, Step-by-Step. There’s also a video on how to use it here: Using the Custom Branding Irons.

I’m working on a publication that includes a lot of temperatures, and I want conversions of those temperatures to be automatically inserted into the text in a consistent manner and without having to convert them by hand. Michael Mehlich’s excellent fp-package provides some useful functionality for accomplishing this.

\usepackage{fp}

I’ve defined a tempc and tempf command that accept a single value and output a nicely formatted conversion. Using “\tempf{67} is nice, but\tempc{-4.5} is cold.” produces the output below. Note that the text inside the brackets is set a bit smaller. Conversions from Fahrenheit to Celsius always get one digit after the decimal point. This example uses text figures (The vertical positions of the numerals vary to make them more readable on a line.) as opposed to line figures.

LaTeX Temperature Conversion Example

LaTeX Temperature Conversion Example

Here’s the code:

% Temperatures...
\newcommand{\tempc}[1]{\FPmul{\x}{#1}{1.8}\FPadd{\x}{\x}{32}\FPround{\x}{\x}{0}
#1\textcelsius\ [{\small\x\textdegree F}]}
\newcommand{\tempf}[1]{\FPsub{\x}{#1}{32}\FPmul{\x}{\x}{.5555555}\FPround{\x}{\x}{1}
#1\textdegree F [{\small\x\textcelsius{}}]}

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