Hypertherm powermax 85

Etkoehn wrote:

How thin of material do you think I will be able to cut with no issues?

Hard to say exactly as there are several factors to consider, but in general for thin plates piercing is the main issue, and that depends on plasma source solely, some use the same air pressure for pilot and cut, some have 2 valves where the lower pressure is used for pilot and higher for cutting, some have built in delays of 0.2 to 0.3 seconds, etc etc.
Again in general, lower pressure and no delay gives better chances of successful cutting of thin materials. If plasma has pre-flow that also helps a bit on plasma's with only one valve.
Another thing, cutting pressure is usually 5 BAR for normal plasma sources, but they all work down to 4 bar, so lowering this also helps.

Weaving pattern on the cuts, do not worry to much about it, setting microstepping to 1/16 will do just fine, 1/32 will be hard to see even when looking hard.
Do some test at different speeds while jogging, find the speed where the resonances start, make a note and try to avoid those speeds. when cutting.

Again, do not worry, build the machine, do some tests, see how it behaves, then you can decide if there is anything to improve/de-rate/speedup/tune etc.
Resonances are not instant, takes a bit of time for them to start and affect the machine, hence the above about avoiding it, otherwise while cutting usually the machine will pass over those resonant speeds so quickly you wont even notice. So while speeding up and down mostly they are not noticed at all.
All machines will have several resonant frequencies, from motors, friction, ball bearings, carriages, belts, rack/pinion, etc etc.
The good thing with steppers is they vibrate the most at low speeds, and with a bit of reduction are easily avoided.
Example, my machines (build logs on this forum) will resonate on Y axis moving at 150-250mm/m, i never cut at those speeds so i never notice, i found this out during testing and tuning.