If you've played Kubb only once or twice, or if you always use the same set, you may have the impression that all Kubb sets are the same: that they are all a 'standard' size. You'd be wrong.
Historically, the pieces would have been made by hand from whatever wood was available, and there would have been a pretty wide variation in size and weight. In the world of machine assisted manufacture, a lot of this variation within a set has gone, but it still leaves the question of what is the 'right' size.
Most sets available in the UK have Kubbs that are around 55mm square, with batons around 30mm in diameter. If you search hard enough, you'll find 60mm square Kubbs in some sets, although often you won't know what you have until they arrive on your doorstep.
Looking at the VMI Kubb (World Championship) rules seems to reveal a 'Gold Standard' to measure against:
So, 70mm is the World Championship standard. That's quite a chunk of wood, and certainly a lot bigger than the Kubbs in the set that I got from Amazon, with their puny girth of 55mm. The U.S. National Championship rule book (from which our own is adapted) suggests the same size: 70x70x150mm. You'll see that the batons are 44mm diameter, again, the same as for the US competition. That shouldn't really be a surprise, because the U.S. rules have been adapted from the VMI rule book.
The difference between 30mm batons, like the ones in my retail set, and the 'standard' 44mm batons as used in the U.S. and World Championships, is immense: 30mm feels like a section of a broom handle, whereas 44mm feels like a section of a scaffolding pole!
Anyway, it turns out that a 70mm Kubb set is pretty hard to get hold of in the UK. These guys sell a great looking set advertised as "World Championship Size" with 70mm Kubbs (yay!) but only 39mm batons (boo!), but I suspect that the shipping from Australia would have killed the deal for me.
So, what does one do? One makes a set one's self.
If only it was as simple as that. The U.S. rules also specify a weight range for the pieces:
Its worth pointing out that the U.S. guys basically looked at all the sets that they already had and then decided that, by definition, they were all within the right range. I like that practicality, and although the weight is only 'recommended' according to the U.S. rules, I want something to aim at.
Just thinking about the Kubb for a moment, we have 7x7x15 cm3, weighing between 300g and 500g. That gives us a density of between 408kg/m3 and 680kg/m3 with a mid point of about 544kg/m3. Working out the density of the batons and the king comes to pretty much the same result. Phew! Sourcing different woods for each component would have been a bit of a pain.
So, we need to find some wood that has a density of .540 (ish). Hmm.
Googling a wood density chart (easy to find) gives a few surprises. Lots of hard woods like oak or beech, that you might have expected to be our friends, are too heavy, and anyway, we are sort of restricted to what we can get hold of at a sensible price. My plan is to make a bunch of these sets, and I am working to a budget.
European Redwood is pretty easy to get in big pieces (remember we really need 90mm x 90mm for the king) is reasonably cheap, and turns out to be about the right density. Result!
In my next article I'll relate my attempts at making a Kubb set equipped with a lot of optimism, almost no wood working skills, and very few tools.
Wish me luck!