Rock-tumbling in reduced gravity?

  • #1
Nik_2213
1,182
459
Protagonists need to 'improve' many ~10mm OD 'mini-musket-ball' spheroids' sphericity.

They've been made by chopping 10mm steel rod stock to 2/3 cm lengths, zapping to molten with eddy-current coil in inert atmosphere, the now-round blobs allowed to cool along a low-g drift-line.

But they're not quite 'even' enough. ( Note: NOT intended as ball-bearings... )

So, partially-immersed 'Rock tumbling' with grit would seem the way to go.

Space-station environment ranges from near-axis tidal / micro-gravity to approx 1/3 g (spun), but the latter, habitation area would not be happy with the noise...

Best I can think of is akin to a fun-fair ride, akin to a 'Waltzer', where a pair of drums ride between ends of two rotating arms, are belt-driven so they rotate at similar RPM to the arms, on parallel axes....

Any better ??
 
Physics news on Phys.org
  • #2
I would say that you could put the tumbling/milling operation on an extension from the station for higher G-forces. How advanced of a space faring society are we talking? Relatively near-term, or something more akin to The Expanse?
 
  • Like
Likes Nik_2213
  • #3
  • #4
So, making a deployable structure to carry the tumbler units out to a high gravity area is not going to be an issue. I’d say use a fairly standard tumbler design and just… basically put it down in a 1-G zone on an arm extending from the station? You can put them on vibration isolation mounts to mitigate the noise.

If you’ve ever played Elite: Dangerous, there’s a few stations with setups like that, sticking out well away from the rest of the spin station. Long-time players call them “noob hammers” because new players either don’t know they are present and can destroy their ships, or they think you can dock with them and then get smacked.
 
  • #5
Nik_2213 said:
They've been made by chopping 10mm steel rod stock to 2/3 cm lengths, zapping to molten with eddy-current coil in inert atmosphere, the now-round blobs allowed to cool along a low-g drift-line.
I understand the necessity of a really cool manufacturing scene, but in real life any sane engineer would just go with forging. Lot less trouble: time, space, energy.

 
  • Informative
Likes Nik_2213
  • #6
Thanks, Rive !!

How you'd contrive that real-neat forging 'mill' pair is an interesting problem:
Could it be done using eg the big mill/drill & lathe tooling of a WW2 'Battleship' work-shop ??
 
  • #7
??

Old style workshops were fine for (relative) small work (everyday maintenance, repair) only. Not tooled for bigger works or for complete machinery builds. But for 10mm sized balls, I think even those workshops would be able to produce something temporary, low production rate machinery.

But in a SciFi setup these days, at least a decent sized metal 3D printer would be included and that would solve most of the problem.

BTW1: if you only have a low tech workshop, then where does the raw material (rods - well, rather: wires) coming from? How/where is that manufactured?

BTW2: that mill is not really 'neat': for anything precise (ball bearings) it's just the very first step. It just fits the description of 'spheroid' :wink:
 

Hot Threads

Recent Insights

Back
Top