I'm having trouble posting a more detailed reply, but found you won't have any problem with four pairs of teams sharing facilities if you can select pairs of teams on the "ribbon" where the team with the higher pairing number is leading the way around the ribbon. For example (16 7) or (13 4) or (17 8) or (11 2) should all work.

If you look at my table (in the link), look at the order of 20's opponents to get suggested pairings (1st column) . You can observe how paired pairing numbers interact with no 20 by looking at the first two columns in consecutive rounds.

--------------------------------------------- The following is what I tried to post earlier-------------

After some more thinking on this, I think I have a better solution. To see how a round robin works, visit

here. To make it applicable to team events, substitute

**team** for

**player**,

**White** and

**Black** become

**Home** and

**Away**. Substitute

Week for

Round. The "Board Number" shows where players, er, teams, meet other teams a given number of positions ahead or behind them on a "ribbon", except on "Board 1" where the team with the highest even number does not move and and other teams come "there" on the model.

I have shown the first two rounds (weeks) and just the first two boards on all other rounds. Outside of the first and last week, the teams in the 2nd column (Board 2) have just met team 20 or will meet that team next week. The order of players on the ribbon is the same as the order as 20's opponents. When not playing 20, no adjacent teams on the ribbon can both be home or away the same week; it is only when they meet 20 is there a potential problem. The full table is

here, choose Porter, Board Order, and 20, perhaps checking Double Round Robin as well.

In this table, the first named team is Home and Teams 1-10 will be home against 20 while 11-19 will be away against 20. To make this work,

**the team with the higher pairing number must be in the lead**, e.g., 13 and 4. In week 6, 13 plays at 20 while 4 hosts team 3. In week 7, 4 hosts team 20 while 13 plays at 14. Other pairs which would work are 15:6 or 17:8 or 19:10. Hope this helps!

19 or 20 players

Rd Pairings

** 1:** 1-20 11-10 19-2 12-9 18-3 13-8 17-4 14-7 16-5 15-6

** 2:** 20-11 2-1 10-12 3-19 9-13 4-18 8-14 5-17 7-15 6-16

** 3:** 2-20 12-11

** 4:** 20-12 3-2

** 5:** 3-20 13-12

** 6:** 20-13 4-3

** 7:** 4-20 14-13

** 8:** 20-14 5-4

** 9:** 5-20 15-14

**10:** 20-15 6-5

**11:** 6-20 16-15

**12:** 20-16 7-6

**13:** 7-20 17-16

**14:** 20-17 8-7

**15:** 8-20 18-17

**16:** 20-18 9-8

**17:** 9-20 19-18

**18:** 20-19 10-9

**19:** 10-20 1-19