Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

OKMO  Microcosm JO6A its billed as the World's Smallest Vertical Stirling Engine. 

It's VERY small and just beautifully constructed miniature Stirling Engine.

Those really are amazing little engines!

Also referred to as a "Mini Wiggers", which I can definitely see why, and with the high-speed action being too fast for the camera, you don't even need to go slo-mo to see the wonderful motions of this little gem!

Just a tip that makes running most of these little engines easier for me is that I drill out the burner's vent hole just enough to allow my smallest syringe needle to go in, so I don't have to fiddle with unscrewing and re-screwing the lid for every run!

Thanks guys, this is a really nice little runner and truly screams along!

Enlarging the hole Daniel can be problematic as it can cause a secondary flame igniting and venting out, this burner is the smallest (by far) of Jin's
Honeybee line of Stirling's and its literally no larger than the tip of your little finger.

Yep, I know all that, as I've got one too.

 The hole at the size it arrives can give a venting flame as well and I only have to enlarge the hole to the next size to get my syringe to fit. Kind of wish that the vent hole was actually very close to the wick hole so that when it does vent and flame, it would be right under the heat cap anyway. The vent hole as it arrives here is about 0.018 - 0.019 and my little syringe needle needs a 0.020 hole which is about a #76 drill.

Yes, it does occasionally flame out the vent hole, but does no harm doing so, and it actually occasionally did so before I drilled it as well.

Quote from: Stoker on December 01, 2025, 06:03:24 pm

Quote from: Jim on December 01, 2025, 04:53:50 pm

Thanks guys, this is a really nice little runner and truly screams along!

Enlarging the hole Daniel can be problematic as it can cause a secondary flame igniting and venting out, this burner is the smallest (by far) of Jin's
Honeybee line of Stirling's and its literally no larger than the tip of your little finger.

Yep, I know all that, as I've got one too.

 The hole at the size it arrives can give a venting flame as well and I only have to enlarge the hole to the next size to get my syringe to fit. Kind of wish that the vent hole was actually very close to the wick hole so that when it does vent and flame, it would be right under the heat cap anyway. The vent hole as it arrives here is about 0.018 - 0.019 and my little syringe needle needs a 0.020 hole which is about a #76 drill.

Yes, it does occasionally flame out the vent hole, but does no harm doing so, and it actually occasionally did so before I drilled it as well.

Just ask your Doc (or drop into a Vet) and ask them for either a 25G or 26G syringe needle and no need to have to drill, the vet should have some blunt tip ones as well.

Fine for anyone who needs them, but I already have a batch of the tips that work fine for me, once I drill the hole, which takes all of about 30 seconds and I can't even see any chips being made while doing it as the fit is already that close. However, with my clumsy and deformed hands, screwing that little burner lid off and on is a real PITA of a challenge sometimes, especially when near full of alcohol!

Probably just me having these issues .... but I do.