Project Plasma CNC

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Versie door DirkWillem (overleg | bijdragen) op 6 mrt 2019 om 11:07 (Todo's)
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Notes on re-working the existing Grote_CNC_freestafel into a Plasma CNC cutter with our new PlasmaCutter

Todo's

  • measure the length of the various cable runs
  • confirm exact sizes/threads of the current pneumatics used. Including the HBM ones (in at least one case a 1/8 was sold as a 1/4).
  • understand how hard it would be to build / use the extra HF /pilot arc wiring we have on the plasma pen:

I am a bit confused as to the naming - it seems that the industry now calls the spark-gap starting HF; and the HF pilot arc; and the true pilot arc something like separate pilot arc.

So if we have an expert - or someone enjoys becoming one - yes please !

  • find 20-30 meters of shielded cable & rewire all emergency buttons in a ‘star’ configuration (all to one point as opposed to a loop).
  • ask our resident electronics experts very nicely to make us some `opto’/something separation for these long wire runs with a relatively solid voltage/current through the switches. (Bonus point if you manage to do the entire thing optical; including the buttons themselves!).
  • see if we can get enough flow through the existing 3.2x6mm tubing of the gantry; and if not upgrade that to a 5x8 diameter. Which is not entirely trivial as the current CNC has a solenoid. And it has to be flexible.
  • bit of a tedious (but rewarding) task of removing all the old wires/no-longer-used wires from the energy cable trains and feeding the new ones through.
  • find a handful of small size quick release pneumatic connectors that match above. And while we do that - also connectors for the alignment lasers and the grounding wires.
  • find some flexible wire suitable for 40A / few kWatt / 20m-ish? (and ask our resident electronics / physics experts if it helps if this is shielded).
  • move the current dangling connectors to a small box/plate on the Z-axis so we can swap heads. Do something clever with the suction pipe to make it fast/easy release.

Volunteers

Dirk will be looking at the pneumatics, fittings, gaskets, solenoid and the connectors in the next couple of days.

Specs

  • plasma cutter
    • max 40A, few kWatt ?
    • trigger switch is wired to 'CB mic' style two prong connector (male on unit; female on end of wire).
  • air inlet hose plasma cutter 8x5 (Outer diameter, Inner Diameter) - pressure generally 5 Bar or about there.
  • air hoses on the CNC machine now: ~6mm outer diameter
  • CNC torch
    • Outer diameter around 29.5mm
    • air seems G1/8 inner thread
    • second brown wires goes to tip -- HF/pilot starter?

Notes, links

Ordering

  • Small set of spares for head.
  • CB plug; female, 2 polig
  • 8mm outer, G1/4 outer coupler for 8x5 to Euro insteeknippel
  • Right euro insteeknippel
  • Suitable earth connector (e.g. yellow banana plugs/chassis) 1x female, 3x male)