PlasmaCNC: verschil tussen versies

Uit MakerSpace Leiden
Ga naar: navigatie, zoeken
(→‎Specs)
(→‎Specs)
Regel 63: Regel 63:
 
** air seems G1/8 inner thread
 
** air seems G1/8 inner thread
 
** second brown wires goes to tip -- HF/pilot starter?
 
** second brown wires goes to tip -- HF/pilot starter?
 +
* Should get away with 2.5 mm^2 copper wiring: 10m 2.5 qmm Cu is 0,07 ohm -> 2,5V verlies bij 40A according to Aart. May be a bit more if we need to add a connector.
  
 
= Notes, links =
 
= Notes, links =

Versie van 6 mrt 2019 om 20:05

Notes on re-working the existing Grote_CNC_freestafel into a Plasma CNC cutter with our new PlasmaCutter

Rough Plan

  • Find a proper 8x5 flex-tube to Euro2 pneumatics coupler for the main box.
  • Wire up Aart his [plasma torch 'pen' style using one of the spare mounting plates for the CNC machine.
    • It seems to have an extra pilot wire/HF capability.
    • It has a spacer ring.
    • We have no spares yet.
  • Re-use the existing pneumatics
    • Current is 6mm OD v.s. cutters 8mm OD -- so we need to check the flow. And otherwise increase diameter for all
  • Make it easier to swap heads (wood v.s. plasma).
    • We have nice quick release plates - but the bold is a bit hard to get to
    • We currently do not have easy connectors for the earth-wire; alighnment lasers and the air.
    • The power connectors are a bit of a mess
    • We have several unused wire runs in the flex-chain.
  • The current emergency stop buttons pick up interference from the plasma cutting - which upsets the FGPA/embedded CPU and the keyboard of the PC.

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).
    • Around 150 Liter/minuut air usage: implies 5mm tube inner diameter is fairly minimal
  • 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?
  • Should get away with 2.5 mm^2 copper wiring: 10m 2.5 qmm Cu is 0,07 ohm -> 2,5V verlies bij 40A according to Aart. May be a bit more if we need to add a connector.

Notes, links

Ordering

Overgenomen van "https://wiki.makerspaceleiden.nl/mediawiki/index.php?title=PlasmaCNC&oldid=5090"