Ardenian said:
fall onto different facets (specifically, on my 20 sider) than do my "new" set of metal dice.. why did they change the design, was there a mathmatical reason, or just a different company?
i just found it interesting.
Different companies produced different "patterns" of numbering dice - even d6's where opposing sides didn't add up to 7. There's no mathematical reason for it as such. Some people will tell you they can control the roll of a d20 such that they can control the probabilities. With EXTREMELY rare exceptions I say that's a load of crap. D6's maybe, on short drops/throws, but not d20's.
But it was my experience that the patterns USED to be two sets of 0 through 9 on two halves of a die with the SAME number on opposing faces. Eventually they seemed to realize that two sets of 0-9 meant having to repaint or re-ink one half, or to use TWO dice to actually derive a range of 1-20. They then started just numbering them 1 through 20 as they should have been doing all along. It was probably a decade before the geniuses realized this.
The arrangement of the numbers doesn't have an effect upon the probabilities of any given face coming up more or less frequently. If you want to be anal about it then yes, having a little bit more or less plastic on one side or another as the number is molded into it will alter the weighting, but it's insignificant outside of long-term gambling concerns.
These days RPG dice are much more uniform from company to company. And the plastic is better too. No, really. Early RPG dice were sometimes made with brittle, grainy, low-impact plastic that would rapidly wear down corners and edges of dice being rolled on hard tabletops.
I still keep, and still use some of my earliest game dice for sake of nostalgia. Doesn't change how they roll.
One exception is that some of the first new "cool-factor" kinds of dice were made of clear plastic. They actually sucked because they were so hard to read numbers off them. But, you could see through them - and see the AIR BUBBLES in the plastic inside. Since these were still being numbered 0-9 twice you could set them down on the table with more of the air-bubble on the top half, the top number would then be statistically more likely to come up because there was more plastic on the lower portion of the die, weighting it. You could then ink the dice appropriately. Not that it really changed outcomes so that you could actually SEE the difference during play. It just felt a little like having permission to cheat in a small way. These dice went away fairly soon, both because improved manufacturing removed the air bubbles and because clear plastic dice were hard to read. Between the two factors they fell out of favor quickly.