Thanks for the update Rual!
Looking forward to hearing how the "odd-odd" chainring-cog combination works out for you. Idworx, for example, champions the odd-odd mix as promoting extended drivetrain life through better distribution of wear. They offer 104BCD stainless tool-steel chainrings in 35, 39, and 43 teeth but none in 37.
A few suggestions on chainrings for you and others seeking 37T in a variety of BCDs:
• Blackspire makes a Mono Veloce 104BCD in 37. e.thirteen (E13) also offer and 37 in 104BCD, which won't help you, but might be useful to others who are running 4-arm Shimano Deore cranks on OBBs.
• Warhawk (
http://www.warhawkindustries.com/chainrings/5-bolt-110mm-bcd-chainring.html ) make 104BCD and 110BCD chainrings in 37t in 7075 T-6 aluminum, 316 stainless, and 6Al-4v titanium in standard-tooth configurations. Even-numbered 'rings are also available in narrow-wide, which allows drive engagement on both inner and outer chain links. Irrelevant to Rohloff use, narrow-wide chainrings also aid chain retention without the need for a front guide or derailleur when used with 1x drivetrains. They work especially well with clutch-type rear derailleurs that maintain even chain tension by eliminating rear mech bounce on rough terrain.
• Sinz BMX chainrings are sometimes available in 110BCD 37t versions made from forged aluminum, which has then been milled. Best chance for off sizes is in silver, as color-anodized versions tend to favor even sizes.
• Praxisworks and Chop Saw (via BMX supplier PorkChopUSA) each make a 104BCDx37t 'ring.
• American cycling manufacturer Ted Durant's RONA manufacturing (Heron bicycles) in Milwaukee, WI produced chainrings under the Willow label (Triplizer, Willow). Chainrings are available in 110BCDx37t. These may also have been marketed by QBP as Engagement chainrings and by Salsa. None seem to be currently supplied any longer, but a quick search shows many available as NOS at bargain prices. David Banzer at Treetop Cycles bought a huge lot from Ted, and some of those are still available from Treetop Cycles:
http://treetop.bigcartel.com/ Specifically:
http://treetop.bigcartel.com/product/willow-chainring-110-bcd-34t-39t-optionsHopefully helpful,
Dan.