If you try to make a seal by pressing glass or sapphire into hard metal it is going to crack. The solution is to plate the hard metal with a soft metal. Gold is ideal here. You can buy pen type electroplating machines. This may look ugly if you are sloppy. I don’t care but we should research soft metals that are silver. Gold is also a good solution if you want electrical contacts. Kodak electroplated some of their batteries some of which rubbed off on the electrical contacts. Gold can be mechanically plated. The cost is minimal since we are talking about .001 inch layers. When amorphous diamond becomes cheep we can then discus the gaskets used in diamond anvils. Because who doesn’t want a light that works at the bottom of the Mariana trench.
O rings often used as gaskets between the bezel and glass, any reason to complicate things using gold?
I presume there’s some engineering/science which determines the size of hole you can seal Vs the ductility of a material, I’d assume rubber/viton/silicone is squishy enough to seal almost all gaps?
As for seals:
O-rings are going to be much more forgiving with irregularities on the 2 surfaces. Easier to disassemble and reassemble. Much more forgiving with bumps in the night. Likely better at pressure and temperature swings. For flashlights I don’t think we need to reinvent the wheel or the seal.
Some early cars and trucks basically used a giant rubber o-ring on a wheel as a tire.
And now with those ridiculous low-profile tires “tuners” slap on, we’ve come full-circle.
Except to some degree it does improve performance. I find the skinniest tyres in general are with people slapping 25 inch chrome rims on a car, or on lifted trucks, while people who seriously build cars for performance may use lower profile than stock, but not “rubber band wrapped around giant rims” level. There’s a reason most racing cars use lower profile than road cars.
My ancient Cavalier came with 80-series balloons, and rode like it. I slapped on some Z-24 rims and 60-series tires, and it stuck to the road like it had claws. Yeah, stiffer KYB struts/shocks all around, but I never lost confidence in the way it handled.
Now, my older car has stock 60s and newer one stock 50s, and they still ride great. Stock all around.
A bud slapped on some… I think they were 25-series rubber on oversized rims, and it rides like shiite. Not only do you feel every bump, but the damned thing bounces around like a superball. There’s no “give” for the tire itself (first line of defense against road irregularities, after all) to be able to absorb any bumps or jolts. And hit a pothole, say goodbye to the rim.
Oh, and the tracks the modders ride on are usually glass-smooth, not like normal streets which more resemble a lunar landscape around here. For me, 50-60 is about the best tire profile.
You do not need gold plating, you need o-rings. when things get hot, materials expand, at different rate, even with gold it will most likely crack.
Sidewall height is a ratio, so 50 on 185 tires will be very different than 50 on 225 tires.
Okay… and?
It’s a way more convenient measurement than absolute lengths.
(And yeah, I always thought it was mental to have width in mm and diameter in inches. But at least they got aspect-ratio right.)