One thing to consider is that PTFE makes good seals for many instances, but it does not have much "elastic memory", so under clamping pressure it can slowly "flow", reducing the clamping pressure, so under pressure can eventually allow leaks. Rubber type gaskets that retain their elastic memory will retain the clamping pressure far better, and paper/composite gaskets once compressed also retain the clamping pressures much better. There are some PTFE compounds that have fillers that help a a lot.This is maybe a good spot to insert some miscellaneous items.
My instinct was that gaskets on specific mating surfaces they would be beneficial. Or at least that’s what I usually see present on commercial engines to seal air/gas, fluids or even help with fastener retention under vibration or heat cycles. The plans were a bit vague on this other than the nose case oil bath area.
I did some experimenting with typical squeeze tube type sealant/gasket products with mixed success. There are so many products out there & admittedly I don’t really understand the variations of metal-to-metal vs in conjunction with gaskets. Actually, of the goopy products I liked, the problem was usually they worked too well. Disassembling the engine parts was quite difficult because of their delicate size & cleaning off stuck residue was a chore. I expect to be in & out of the engine often so I wanted something that lent itself to that. I can produce CAD based export formats for a computerized cutter, I don’t have a machine & it seemed excessive to outsource it for the low parts count plus spares. I see there are some interesting cutting machines used by crafters for cutting stickers & such, but I suspect the software/import capability might be another rabbit hole & again hard for me to justify.
So, I went old school & just hand-made ‘acceptable accuracy’ templates from scrap MDF to act as a cutting guide. I laminated my paper shop drawings onto the MDF & cut them out on the scroll saw. The gasket material I found (actually copied from another builder on the forum) was Teflon sheet, I believe also known as PTFE. The nice thing is it comes in very thin sheet thicknesses, starting at 0.001” depending on the supplier. Its impervious to oil & fuel & even used as head gaskets that see significant heat. I sprayed a light mist coat of adhesive onto the material which tacks it into position on the template. Then cut the outline along the template with a sharp Xacto or scalpel on a cutting mat.
I first tried drilling the gasket clearance holes for, in my case, M3 fasteners to pass through but a drill seems to make a raggedy non-circular profile even with backing board behind. So, I made a simple tool from O1 so that I could harden it & preserve the cutting edge. I used a 4mm ball end mill which made a natural edge to the ~3mm shank. It cut the sheet with a slight twisting motion or using cordless drill. I think the slight give of the cutting mat helps & also preserves the cutting edge. A punch style template might make better holes but would involve another mated template. I also think a thinner, harder cutting template like 1mm aluminum or plastic might allow better access for the blade on internal holes, but the MDF will last for what I need it for. To release the finished gasket from the template, it just needs a spritz of acetone or thinner. The spray adhesive dissolves clean & the PTFE is impervious.
Only over 60s are allowed to be this grumpy. It takes that long to develop the mental attitude, based on historical experience, to determine the short-comings of most things in life. (like the $15,000 you have not got).OT
(Blubbering in my water - - - - if only I had the $10 to 15k usd for a copy of solid works (with the options that I think I want) - - - - but then I'd have to run M$ Win and then my mood has to improve.) Fortunate man to have such.
Thanks for sharing - - - - hopefully I'm not too grumpy!!! (LOL)