1/2 a mm for the full circumference is actually a lot of contact - plenty to support 24 amps, and more, as it does now. The noticeable wear is not something to be concerned about in the near future, since the ground ring is extra thick. I prefer using the electronic lockout. The mechanical lockout is only as good as the anodizing on the threads, which will wear with time and use, and it's not perfect on many Q8's from the factory to begin with.
So you can choose between wear&tear on the switch, or wear&tear on the threads and ground ring. If you do couple/several lockouts per day, then maybe, just maybe it might be an issue within 2-3 years. I personally tested the mechanical lockout on a Q8 about 275 times or so and saw no "significant" wear on the ground ring. Posted bout it earlier somewhere in this thread: https://budgetlightforum.com/t/-/39069/5597,
I was quite concerned at first, particularly as mine started off with very partial contact around one driver screw, hence me taking it apart, sanding, polishing and lubricating.
Now I do have 360 degree contact, but it continues to “bed-in” evidenced by the indexing of my tube continuing to shift.
I hope this settles down soon.
I remember that the copper layer was specified to be heavy on the driver ground ring, for wear resistance, but I also recall that that is maybe not what we have ?
It certainly works well, as you say, the tail springs and screws etc. are clearly the bottleneck.
Just came across a Q8 batch 2, just came in, that had a solder blob on the driver ground ring, but on the inside (component side). Really caused a significant tilt of the driver. Used an Xacto to cut/scrape it off. Though they improved the screws and threaded holes (no more glue/contaminants or burrs on the edge of holes), it's still worth giving the light a good close inspection.
I just measured and ran some calculations, battery tube to driver ring contact is approximately 208 mm^2. Assuming contact around the full perimeter. There will be bedding that happens, and making sure that the driver board is flat should certainly be done, but I agree with Tom, it should last a good long time unless you are mechanically locking out or swapping batteries multiple times per day.
Finally got it!
Getting more “messed up” in my opinion/personal experience with Postnord lately here in Sweden for the final delivery on gods from China.
Anyhow,
Very high finish, extremely happy with functionality and super a value for my money so just very pleased with it.
I would have ordered another right now, but currently out of stock but thanks Tom E for the heads up.
And once again,
BIG Kudoz to all involved with the project, and glad to read there where a few bucks over to some of you.
V1.1 had some life to it, can't recall details, but think it was a temporary release for the GT buck driver. So to avoid any confusion I bumped the rev number.
It's been common practice for me that if a release "leaves the building", then if in doubt, bump it out (up??). Out rhymes though