Saturday 25 January 2014

Low Number Bolt & Nipple Bolt

Low Number Bolt / Nipple Bolt

Wil Strijbos. For a list of Wil's puzzle designs, click here.

Nipple Bolt left and Low Number Bolt right

Wil Strijbos. Both are around 20 euros each. Not sure whether they are still available but no harm asking Wil. Please PM me via my Profile email if you wish to contact him to buy one.

Type & Classification
Take Apart

7.6 cm (Length) x 3.7 cm (Width)  

Materials & Construction
Steel with a shiny chrome finish although I would have much preferred a matt finish. Well made and very heavy in the hand. These are large size bolt and nuts.

These are the 2nd and 3rd bolt puzzles I have from Wil. The first was the Bolt & Washer reviewed previously in this blog.

The objective of both bolts are to unscrew the nuts and remove the washer.

Both bolt puzzles here look exactly the same with very subtle differences. The main difference is that the Nipple Bolt ("NB") has a plastic "knob" on one end.

As far as bolt puzzles go, both the NB and Low Number Bolt ("LNB") employ mechanisms which experienced puzzlers would likely be familiar with. Notwithstanding, both the NB and LNB are fairly challenging and amongst the hardest so far I have come across. For my experiences with other bolt and nut puzzles, please click on the following links to my other posts:-

1. Cross Threaded
2. Nut & Bolt Puzzles
3. Lee Valley Bolts V1
4. Lee Valley Bolts V2

I don't wish to describe in what sense it is challenging since this would be a give-away and I don't wish to spoil anyone's fun. Suffice to say, even though the LNB has a simple trick/mechanism, Wil has in fact deliberately made it rather difficult and the way it is solved would surprise you.

For the NB, it departs from the typical bolt puzzle by requiring a number of steps in the right order to solving, hence it can also be classified as a sequential movement puzzle; requiring around 4 steps to remove the washer.

If you like bolt puzzles especially ones that provide a good challenge, well, here are two you should get. For the price paid, I  would also consider them value for money.


  1. This comment has been removed by a blog administrator.

  2. I have just got the Low Number Bolt and I'm really struggling with it!!

    1. low number is not difficult but not convenient with fingers...

      Nipple bolt seems more difficult: I don't manage to do anything...

  3. A hint to the Low Number Bolt would be nice. Struggeling with that thing for a week now...