Hi there.

So... i am finally in a stage of planning where i got most things sorted out.

Still got one big and four minor questions where i just need some experience, and build diaries are either telling different stories or nothing about it at all:

1. (big one)
My Weapon will be in a somewhat beater-style, just two of them on one axis, with a 8cm "gap" of only axis between them and a bit asymmetric to give it a better bite, but yeah. At least roughly. but i am really struggling what material, thickness, and how wide the "spokes" should be.
Dimensions will be (roughly) 30cm long (along the axis) and about 25cm diameter when rotating (those would be really hard to change if i had to).
not sure about that yet (some parts still have to arrive), but i think i will have 4, maybe even 5kg to put into that. Somewhere in that range.
But would like to know the "minimum safe solution" for the thickness, so i can try to do the actual designing on my own and just know when i am trying to do something too likely to blow up.

2. Pulley/belt to drive the weapon. What diameter etc. do you guys use in your featherweights? When reading build diaries i get the feeling of "anything is possible", but long-term experiences are rarer in those. So... would like some advice on what actually worked for a featherweight vertical spinner for quiet a time. Else i'd just have to try, but since i can't make my pulleys myself and changing something on them would be some work... planning to get different diameters in case my spin-up-speed isn't what i imagined anyway, but to ask a friend for that, and a bit lter ask him to do it again just a little bit thinner/wider wouldn't be nice

3. Top Armor sheet metal (most likely 3 or 4mm titanium), side armor 20mm HDPE.
Now i want to screw both together.
Considering i might have to get the top off quiet often (for charging, repairs and whatever), hwat would be a reasonable solution here?
i've so far seen/read/heard of
"just take some wood screws und punch them in there",
"drill holes, cut threads in them, and use M5 (or M6, or M7, or... seems everybody got a favourite size) screws in those" and
"drill holes, put inserts in, and then use Mx screws."
Now... the last one seems to be the most professional one, but also the heaviest and most expensive (and possibly most time consuming) option. But also everybody seems to have different distances between those screw, and use different screws (regarding length and thickness), or even give such helpful remarks as "a lot" or "a bunch". I just can't see a pattern there, when you should use what and why and how much/long/wide the screws...
Guess i could somehow put that together, but i am feeling likely to either not make it strong enough or putting so much metal in my HDPE, i could have taken Hardox right from the start. So would be great to have some experience like "i take 5 screws m5 for every 10cm HDPE and (don't) use inserts" or stuff like that, and if you ever had any problems with it.

4.Now this was just an idea... do you know of any bushings coming as two halves? So i could put them on an axis without an "open" end? Would in this case be used to mount my beater to three bushings, two in the ends and one (almost) in the middle. So let's say take a bulkhead, cut it in half, screw it together again, drill a hole where the cut is, screws out again, put both halves of the bushing around the axis, screws in again, and got one mount in the middle of the axis.
Would think that would give it a bit extra stability, but should also work without... at least i hope so.


Now that's quiet a wall of text, hope someone takes the effort to read that stuff and possibly even answer. If you read this: thanks already