Afternoon!
Slight reworking of the high mass core (HMC)!
Found a 30mm washer with a wider inner diameter to go on top, that fits neatly with the star washer underneath. Results in a much more open airflow.
Reworked an oak body for this, as I had to put the thinner walled bodies I made at first to some use yet. Came out a bit on the short side (~8cm hight), as I cut off some millimeters from the bottom, to get rid of the oversized 'mouse hole' opening for the cord
But can always add a bottom cap.
This HMC unit is resistor powered, BTW.
Eager to try one in a smaller 25mm bore, though this seems to work out pretty well so far. The core proper is insulated from the wood by a 5mm air gap all around, only the top and bottom washers touching the wood itself, so the body doesn't get warmer to the touch, than the standard core (SC) bodies
Also... I can't reproduce the top washer combo with smaller diameter washers. Would need a 25mm/15mm one for that first.
So maybe more convenient, to stay with the 30mm bore for HMC units (and reserve the smaller 25mm bore for the SC units) and when we've got additional 45-50mm diameter bodies, the walls will be thicker anyway for these HMC units.
Heavy Metal Core and Standard Core