Tuesday, June 21, 2016

Breakdown, a broken banjo bolt, and glue everywhere.

My SD300 broke down at the end of 2015, its first serious fault.  The machine had clocked over 6000 hours of build time, plus an additional 10,000 hours of power-on time, so maybe it was just about time something broke.

I had to mail-order various replacement parts from overseas, so I did the work in short sessions over the course of several months.  The machine is running now.

It started when I had left the SD300 running unattended, which wasn't uncommon.  I came home to discover the machine halted with a severe fault, a broken-out panel underneath, and a puddle of solvent-glue.

No doubt there was a glue leak somewhere inside, so I removed the exterior cowl to trace it back to its source.

Opening left side cowling to reveal cable carriers, wiring harnesses, and power driver circuits.

Solvent-glue had leaked onto the cowling panel and melted through the bottom.
There was melty plastic residue all over the cable carrier for the iron bridge.

Rolling back the cable carrier revealed even more plastic residue.

A vinyl wiring harness had disintegrated where it crossed under the steel-armored tubing at the end of the cable carrier.

The solvent deposited plastic reside everywhere it leaked throughout the SD300.

The source of the leak was a tiny, hollow banjo bolt that had broken in two.

Evidently the leak originated at a hydraulic connection, referred to as a banjo fitting, where a steel-armored PTFE tube was attached to a manifold by way of a hollow bolt that had been broken in two. This is a common type of connection in hydraulic equipment, but the SD300 employs an uncommonly small size: that's a tiny 5 mm screw thread!  It was really tough to find a matching replacement in North America, but I eventually managed to source a replacement through Airlines Pneumatics in the UK.

But the SD300 needed more than just replacing the broken bolt because the solvent glue had traveled along the armor of the PTFE tubing by capillary action and destroyed a vinyl wiring harness that had been routed through the same cable carrier.  The damaged harnesses and fittings needed to be replaced, too.

That's enough about the damage.  The machine is repaired, but I'll post pictures of my repair work separately.

Sunday, October 11, 2015

Color! Using Dyes on 3D Printed Vinyl

Material for the SD300 is offered in a very limited selection of colors, so naturally I was intrigued by Sean Michael Ragan's blog post Stain PVC Pipe Any Color You Like.  So I bought an assortment of Sculpt Nouveau solvent dyes and tested them on 3D printed vinyl parts from the SD300.  They emerged brightly tinted in candy-like colors!

Solvent dyes are very highly concentrated, but they're formulated to be diluted with solvents--like the name implies!  I tested a variety of PVC solvents, using disposable pipettes to measure similar volumes of dye.  Not surprisingly, I got the best results from the most powerful solvent, SCIGRIP 2007.

The solvents I tested, starting with the most satisfactory:

  • SCIGRIP 2007 (formerly Weld-On 2007) tinted the SD300's vinyl parts very quickly, reaching full color in 15-20 seconds.  It also strengthens 3D printed parts and leaves a glossy finish.
  • Oatey Un-purple Primer was almost as effective as SCIGRIP.  It's a PVC pipe primer without the usual purple stain; instead it contains a UV-sensitive fluorescent dye that makes treated parts glow under blacklight.
  • PVC Pipe Cleaner with THF (various brands) was substantially less effective than the solvents above, and it took longer for parts to absorb the dye.  Look for THF or tetrahydrofuran under the caution label.
  • PVC Pipe Cleaner without THF was least effective.  It took more time, it did not strengthen parts, and it did not leave a glossy finish like the choices above.

After testing such a wide assortment of solvents, dyes, and tints, I made dozens of these little test puzzles so I handed them out at this year's International Puzzle Party in Ottawa.

I've also been experimenting with a subtle green tint, trying to imitate the appearance of real glass.

Monday, August 4, 2014

Building Puzzles for IPP34

I'm busily cranking out puzzles to exchange, trade, and sell at IPP34.  In addition to a few old-standy puzzles here's a look at what's new from me this year...

Join The Club

For the Puzzle Exchange, this consists of two identical pieces that can be joined together to make a ♣ club shape.  Testers at my office gave me plenty of feedback and guidance, and it took some real effort to implement their suggestions.  My early revisions resembled an ordinary clover leaf, but testers insisted it needed a widely flared base in order to resemble a Club suit--it took some design ingenuity, but I made it work!


Although I have built plenty of cubic dissections in the past, this one really surprised me!  It has two identical pieces that can be joined together to make a cube, but they just as easily join into a variety of abstract shapes.  It's a fancy-looking objet d'art when placed on a light stand, although it's hard to get a picture that shows how pretty it really looks.

Pink Marble & Yellow Marble

These are successors to the colored marbles from the Bag of Marbles which I had previously sold.  Pink Marble is a two-piece puzzle, the first in the series that can only be joined together at one specific point on each piece.  Yellow Marble is a three-piece puzzle that goes a step further; it's the hardest of the series, but not overly difficult for the average solver.

Credit-card-size SIM storage

This isn't really a puzzle, but it's a useful device when traveling overseas.  It exploits the SD300's laminated construction technique to build a thin storage device that's literally the size of a credit card, with storage pockets for four SIMs and an eject tool (or a paper clip).  Very handy!

Sunday, March 2, 2014

Glue Smear, a super-easy quick fix

Every now and then I've noticed a shiny stripe of SolGL glue across the top layer when a model is being built.  There shouldn't ever be glue on the top surface because it can contaminate the Anti-Glue pens, which makes the model difficult to clean.  Whenever it appeared this stripe was always perfectly centered, with neatly-defined edges.  What's really strange is that it usually appeared when I'd just installed a new roll of fresh, clean material.  How did it get there?

After considerable searching I finally discovered the source of the contamination: looking into the material-supply chamber with the supply roll removed from the machine there's a bar across the bottom of the chamber to prevent the PVC from dangling out the bottom of the machine as it unrolls.

In the years I've been using the SD300 I have never cleaned there because the media door blocks the view of that area as the door opens.

When the door is fully opened, it totally blocks any view of that part of the machine.  But when the door is closed, a full roll of material could easily come into contact with that area.

With the media door mostly-closed, I could see debris had accumulated in there over the years.  And the bar was had traces of SolGL glue that had probably splashed there when I performed maintenance operations over the years.  The glue stayed wet because SolGL doesn't dry up on its own, so naturally it rubbed onto PVC in the media chamber.

No doubt a professional serviceman would have cleaned this area, but I never called in a serviceman because I'd always tried to maintain the machine for myself and it hasn't ever needed professional repairs.

I thoroughly cleaned these hard-to-reach areas using copious volume of alcohol to dilute the SolGL glue and paper towels to soak it up.  Sure enough, that stripe of glue stopped contaminating the tops of models.

A free, easy fix!

Wednesday, October 2, 2013

More Nuts and Bolts

My Its' Nuts toy went on sale at Grand Illusions last month.  Their initial inventory quickly sold out after it appeared in their monthly newsletter, so I made another batch on the SD300 to enable them to restock.

Grand Illusions is a web store packed with all sorts of deceptive novelties, plus an online toy museum and gallery.

Here's a video about Its' Nuts featuring Tim Rowett, an extraordinary toy collector who had purchased a copy of the toy directly from me last year at the International Puzzle Party 32 in Washington, DC.

Puzzle designer Evgeniy Grigoriev created his own version, which he titled the Incredible Screw.  Grigoriev is famous for his twisty-cube puzzles, and twice set the record for building the World's Smallest Rubik's Cube.  On his version, notice how the nuts move at different rates when he turns the bolt!

Matt Ruggles independently designed his own version, which can be downloaded from Thingiverse for anyone who wants to build it.  Here's a picture comparing my original model (left) with his design (right).

Friday, August 23, 2013

IPP Pictures of Puzzle Enthusiasts taking pictures of Puzzle Enthusiasts

Lots of people took pictures at IPP, so here are some pictures of the people who took pictures.

Friday, August 2, 2013

Puzzle Party: IPP33 Opens

When I arrived in Japan for the International Puzzle Party many other puzzlers had already been there for quite some time, and they'd been out sightseeing and visiting.  I joined a small group of friends on an unofficial trip to visit a few puzzle sights, including (pictured above) George Miller, Roxanne Wong (wearing my ivy cap) and her daughter Katherine, and Naoki Takashima.

First we visited Takafumi Haseda, who operates the Tribox puzzle store online.  The store operates in a residential apartment converted into an office, a photo studio, and a stockroom packed with puzzle merchandise.  Pictured, Andreas Nortmann (too tall!), Roxanne, and Takafumi venture into the stock room search for hidden treasures.

Next we trekked to the office of Hanayama, the maker of the world's finest mass-produced brainteaser puzzles.  Above, Oskar van Deventer and his wife discovered a sign that greeted his arrival outside the Hanayama office.

A room at Hanayama displayed their huge assortment of Japanese toys and games, in addition to their world renown collections of cast puzzles.

Our next destination would have been Puzzle Shop Torito, but the shop was scheduled to be closed for a few days.  So we went sightseeing to the 2080-foot-high Tokyo SkyTree.

From the SkyTree we observed a puzzling building that exhibited an illusion like an MC Escher painting: the green roof appears to wrap around the two elevator towers in the center of the building, but the elevetor towers clearly connect to the green roof at different floors!

There's a glass floor for intrepid visitors willing to stand on thin air over 1000' above ground.

Back at the hotel, Dirk Weber successfully solved my Twisty Trillion puzzle.

Hanayama Puzzles exhibited a fascinating display that showed how many of their most famous puzzles evolved before they went into production.

My favorite entry in the 2013 Design Competition was Bram Cohen's Galaxy, which won a jury prize.  It went on to be manufactured by Hanayama Puzzles, widely sold by puzzle stores like Puzzle Master.

Monday, July 29, 2013

Rundown of puzzles for IPP33

Peppermint, my entry for the puzzle exchange, was digitally manufactured in colorful ABS by Bradley Rigdon at PrintTo3D.  I built prototypes on my SD300, those PVC models were a bit too flexible to give the right "feel" for this particular puzzle.  Each piece is made in two colors, red and white; the colors play a subtle but important role.

 Moiré Maze combines laser-cut acrylic and 3D printed vinyl.  The challenge is to guide a small magnet through the maze from Start to Finish.  That goal sounds simple enough, but it's easy to get lost in the visually-confounding patterns of rings reflected against a mirrored background.

Cubic Trisection is one of the puzzles I also sold at IPP32 last year.  The challenge is to assemble the three pieces into a cube, as shown.  All three pieces are identical, but not symmetrical.  Most users easily assemble the first two pieces, but encounter trouble adding the third.

Puckup is a two-piece assembly puzzle, which I'm selling in transparent material or a red-white color scheme.  Tyler Barrett suggested a somewhat edgier name "What the Puck" but the simpler Puckup name had already been picked up on one of the puzzle forums.

Twisty Trillion is a successor to Puckup whose shape provokes a lot more confusion among users.  Neither puzzle is fiendishly difficult, but Twisty Trillion takes most people a whole lot longer to figure out.  I built them all on the SD300 using transparent vinyl because light reflects attractively inside the puzzle.

I commissioned two copies of a Trillion Pendant to be built as puzzle jewelry--one in brass from i.Materialise, the other in silver from Shapeways.  But neither model was delivered on time--Shapeways lost one of the pieces, and i.Materialise is over 3 weeks behind schedule.  So I salvaged the partly-incomplete silver model by building its other half in luxuriously-dark blue vinyl, which contrasts gracefully with the silver piece.  Frankly, it looks nicer than it would have if both pieces had been silver!

Here's a colorful assortment of marble puzzles, three of which will be available for sale as Bag of Marbles.  The others are experimental designs, which I'd like to test on a few puzzlers at IPP.  In particular, the pink and purple models are two closely-related designs, but my first few testers think the purple one is much harder than the pink one.  Will others react the same way?  IPP is a great opportunity to find out!

Monday, July 22, 2013

More on Moiré

I previously wrote about my Moiré Maze puzzle as if it was finished, but it had all sorts of unfinished details until this weekend.  For example I didn't have suitable packaging until George Bell referred me to Clear Bags which supplied the attractive box pictured above.

I built this inexpensive plastic insert on the SD300 to hold the puzzle safely inside the box.

The closeup above emphasizes two more gripes:
  • The Start and Finish are denoted by two bulb-shaped chambers, but there aren't any markings to identify which is which.  I suppose I could supply an instruction sheet, but it could get lost.
  • It really needed some sort of mechanism or barrier to keep the chambers separate, to prevent the user from trivially moving the magnet from Start to Finish without tracing the maze.  The acrylic cutting pattern included an eyelet for attaching such a mechanism, but how should I use it?
To add markings to the puzzle, I used a KNK Zing plotter-engraver I had recently purchased.  The machine can't handle the bare acrylic pieces so I 3D-printed a template and taped it to a large piece of poster paper, which the machine happily accepted.

To calibrate the KNK Zing to the acrylic sheet, I aligned the the engraver's laser-pointer with a small hole in the 3D-printed template/holder.  And I installed a diamond-tipped engraving tool into the plotter.

Start and Finish are clearly identified after engraving.

And I installed a one-way vinyl flap that permits the magnet to be pulled from the Finish chamber to the Start chamber.  It doesn't let the magnet slide the other way.  The only way to travel from the Start to the Finish is to navigate the maze.