Replacing a Husqvarna Viking Designer Topaz 30 Needle Holder

We have a Husqvarna Designer Topaz 30 embroidery machine, and the needle holder recently broke in two. The replacement part only was about 30€. I tried searching for a service manual for that machine, but the results are really sparse and you get to the strange sites really soon… But it turned out that the replacement is very easy, you’ll only need a 1.5mm hex key.

  1. Turn the needle holder to the “down” position using the hand wheel, remove the sewing foot and the hand screw for tightening the needle in the holder.
  2. Use the 1.5mm hex key to open the little set screw on the left side of the needle holder. Remove the needle holder by sliding it downwards. While you’re at it, grab a paper towel and clean the rod from lint.
  3. The rod on which the holder sits is actually a hollow pipe. The old holder had a little groove at the lower end which gripped the pipe tightly when the set screw was put in place, and also the hole for the needle was separated from the fixture hole. The new replacement part didn’t have such a groove at the bottom, and the needle hole was not separated by a wall. Instead the new kit came with a little cap thingy that probably helps center the tube and acts as a stopping point when inserting the needle. I just put the cap thingy into the needle holder, the bulge facing upwards. Works for me.
  4. Put the set screw from the old holder into the upper hole (the replacement kit didn’t come with a set screw), and the tightening screw for the needle into the lower hole.
  5. Put the holder onto the tube as before, align the set screw so it faces approximately orthogonally to the left, then tighten the set screw.
  6. Put a needle and a sewing foot in, and make a few test stitches.

Pictures are better than 253 words:

Old needle holder in the “down” position, with the set screw in the upper hole. The needle tightening screw has already been removed.
Old needle holder in the “down” position, with the set screw in the upper hole. The needle tightening screw has already been removed.
All parts. From left to right: old set screw, needle tightening screw, the new cap thingie, the new needle holder, and the old needle holder, split in two. On the latter you can see the groove at the bottom of the fixture hole.
All parts. From left to right: old set screw, needle tightening screw, the new cap thingie, the new needle holder, and the old needle holder, split in two. On the latter you can see the groove at the bottom of the fixture hole.
View into the new needle holder. Note that the two holes are not separated.
View into the new needle holder. Note that the two holes are not separated.
New needle holder with the cap thingie in place, bulge facing upwards.
New needle holder with the cap thingie in place, bulge facing upwards.
New needle holder with old set screw
New needle holder with old set screw
New needle holder on the fixture, aligned and set screw tightened
New needle holder on the fixture, aligned and set screw tightened
Voilà, it works!
Voilà, it works!

Trying 1.75 mm Filament on the LulzBot TAZ 5

The LulzBot TAZ 5 User Manual has this mysterious section:

5.4 Using 1.75mm filament

Your LulzBot TAZ 3D printer is set up to use 3mm plastic filament by default and may be capable of printing 1.75mm filament with no hardware modification. While many of our advanced users are able to do so, your results may vary.

Since we wanted to use the remaining glow-in-the-dark filament, we decided to try our luck. So we changed the filament diameter to 1.75mm in Slic3r, and printed a few small objects. Everything went as expected, only the retraction moves didn’t work so well and the filament oozed out of the extruder nonetheless. But those strands can easily be cleaned up later, so we went on with some bigger objects. This was when the printer would reproducibly stop extruding after a few layers, and it seemed like the nozzle was clogged up. Investigation showed this beauty:

Apparently the filament was too thin to be directed into the hotend, so it decided to curl up in the space between the hobbed bolt and the upper entry of the nozzle instead. After all, the manual was right, our results really did vary.

2. CoderDojo im Stratum 0

CoderDojoBS - Kuchen (Foto: @CoderDojoBS)
CoderDojoBS - Kuchen (Foto: @CoderDojoBS)

Heute war es wieder soweit und 11 Kinder und Jugendliche trafen sich im Stratum 0 zum zweiten Braunschweiger CoderDojo. In nur drei Stunden wurden mit Scratch wieder viele Animationen, Spiele und Geräusche (*miau*) programmiert.

DEF CON 22 Capture The Flag

The team on the last day
The team on the last day

So, some time earlier this year we made second place at the Boston Key Party CTF. The BKP is one of seven CTF events this year where the winner qualified for DEF CON CTF. The one who came in first had already qualified at that point, which meant we got the spot. The DEF CON CTF is the big CTF event of the year, and one of the bigger events at the (in)famous DEF CON hacking conference in Las Vegas. H*ck yeah road trip to Vegas!

The CTF happened early August, and by the time I finally got to write this blog post, other teams had published great writeups for almost all challenges. So unlike other CTF-related posts, this one’s gonna be a travel report for our casual readers rather than a writeup for the techies. There won’t even be code, I promise!

Das Holodeck steht!

Endlich ist es soweit! Wir können verkünden: Das Holodeck steht! Ein Wochenende lang haben rund 10 Entitäten kräftig gewerkelt und das “Hochbett” in den Space gestellt. Hier finden sich nun noch einige Fotos vom Bau und dem fertigen Holodeck.

1. CoderDojo im Stratum 0

CoderDojoBS

Heute am Samstagnachmittag trafen sich 8 Kinder und Jugendliche bei uns im Stratum 0, um gemeinsam Programmieren zu lernen. Innerhalb von drei Stunden erstellten die Kinder Spiele und Animationen, zum Teil ohne jegliche Vorkenntnisse im Bereich Programmieren.

Mirroring MediaWiki with Git-Mediawiki and gitolite

This post was originally posted on my personal blog. Nevertheless, I think it fits here as well.

From Murphy’s Law we can deduct that Internet failures always come when you least expect them. In my case, the Stratum 0 wiki was offline for a few minutes (only, thankfully!) when I really urgently(1!11) needed to look something up there. If I only had an offline clone of the wiki…