Eric Krusenstjerna - Magic Billet Box (type I) (2017)

⟬ Smallbox Fortnight ⟭——15. Eric Krusenstjerna - Magic Billet Box (type I) (2017)

made from CNC machined aluminum and neodymium magnets.

Eric Krusenstjerna (often shortened to Krusen) has been making these CNC-milled magnetic boxes since about 2006 or 2007. he sold them through his own site for a while (no longer up) and through eBay, and fairly recently moved to Etsy (as magicbilletbox). he may still do custom designs if you have one in mind.

this is an interesting box, but not necessarily a puzzle, so the following description isn't a spoiler. in fact, Eric posted the first instructional video to YouTube in 2007, and he's always been very clear about how they function.

the boxes have outer and inner lids, both magnetically held. there are two methods to open them, depending (i believe) on the configuration of the magnets in the inner lid:

type I is opened by simply inverting the outer lid over the inner lid;

type II is solved the same way, but the inner lid requires additional kinetic energy to release it, and this means giving the inverted outer lid a sharp tap while holding the box. it's a neat physics trick.

here's one of his YouTube videos showing a type II box.

♫: 

—1. everything i have is in the photos.

—2. shipment is by USPS Priority Mail, insured for the full sale price and trackable.

—3. if the auction(s) in which you are the highest bidder have closed, and you are not bidding on other auctions, please let me know and i will organise the invoice. otherwise, shipping will be calculated after all auctions in this Fortnight are closed.

—4. payment is via PayPal only.

—5. all puzzles in my collection have been kept out of sunlight, in a humidity-stable room or sealed plastic container, away from pets unless they can solve them, and in a non-smoking household.

—6. the price for shipping+insurance will not exceed $30. if it costs more, i will pay the balance.

thank you for looking, and good luck if you bid.

:cameron: