Plasma Tables & Torch Height Control

Plasma cutting on a hobby table is a different software world from milling: the consumables-and-pierce dynamics need a CAM that understands kerf and lead-ins (SheetCAM), a torch-height controller that holds standoff in real time, and a controller stack that can run THC adjustments asynchronously to the program. See Machine Types for the table options (Langmuir, PlasmaCAM, DIY), Touch Probes for ohmic probing, and Dust & Coolant for water tables and downdraft.

Plasma CAM software

• ★ SheetCAM TNG — closed source, paid (~$140 hobby / ~$540 commercial); the hobby plasma standard. Tab/lead-in/lead-out generation, kerf compensation, hole-cutting strategies (small-hole pierces, slow-down moves), nesting (Pro version). Pairs with Mach3/4, LinuxCNC, FireControl, UCCNC. The "actually buy this" tool for any serious plasma work.
• Fusion 360 plasma post + manual lead-ins — works but lacks plasma-specific features (auto kerf comp, pierce delay handling). Rare to see used in production.
• Vectric VCarve plasma post — works for simple sign-cutting plasma jobs; not plasma-aware.
• FreeCAD CAM + plasma post — works in theory; rare in practice.
• Plasmacam Design — closed, vendor-specific to PlasmaCAM tables; nesting + post combined.

Torch Height Controllers (the THC box)

• ★ Proma Compact THC — paid (~$250); the hobby-default external THC. Reads arc voltage, raises/lowers Z to maintain standoff. Works with any controller stack that exposes Z input (Mach3, LinuxCNC, FireControl-not-needed). Polish-made, reliable.
• ★ Proma Sensor THC SD — paid (~$400); higher-end Proma; ohmic probing built in.
• Hypertherm Sensor THC — paid (~$2k+); the OEM industrial THC; ships on factory plasma tables. Excellent but rarely seen at hobby price.
• EZ THC (Tindie / various) — paid, cheap (~$130); DIY-friendly; community-supported.
• Forester PT-200 — paid, cheap; Chinese-made; many users.
• FlashCut THC — bundled with FlashCut control system; closed.

Plasma controller stacks (the whole-build options)

• ★ Langmuir FireControl + Langmuir CrossFire / PRO / MR-1 — closed source binary, free for Langmuir owners. Linux-based controller derived from LinuxCNC; THC built in; ohmic probing built in; only runs on Langmuir hardware (Crossfire / Pro / MR-1 control box). The "I just bought a CrossFire and want it to work" path. Very polished; firmware updates active in 2025–2026.
• Mach3 + plasma plugins — paid (~$175 Mach3 + plugin); historic king of DIY plasma. Pair with Proma THC and a USB/Ethernet motion controller (UC100, ESS Smoothstepper). Many plasma tutorials assume this stack.
• Mach4 + plasma plugin — paid (~$200 Mach4 + plugin); the modern Mach answer; cleaner, supported. Default on Avid PRO plasma builds.
• LinuxCNC + plasma config (plasmac / qtplasmac) — open source (GPL); the FOSS path; QtPlasmaC is the polished UI. Built-in THC handling, ohmic probe, hole-cut velocity scaling. Excellent and free, but expects you to build a LinuxCNC PC. The DIY plasma builder's gold standard.
• FluidNC plasma builds — emerging; community plugins for THC simulation; not yet polished.
• UCCNC + UC400ETH — paid; Hungarian; popular European alternative to Mach.

Pierce / hole / cut-quality tools

• Pierce delay tuning — controller-specific dwell after fire-up before motion; critical for clean entry holes. Documented per material thickness in Hypertherm's pierce charts.
• Hole-cut speed scaling — small holes need slow feed and lower THC influence to stay round. SheetCAM, FireControl, and QtPlasmaC handle this with rules.
• Lead-ins / lead-outs — angled or radial entries to keep pierce dross away from the part. SheetCAM defaults are excellent.
• Hypertherm's cut charts — free PDF; pierce time, cut speed, and standoff for each Powermax model and material. The de-facto reference; anyone running Hypertherm has it bookmarked.

Consumables / torches (hardware mention)

• Hypertherm Powermax 30/45/65/85/105 — the gold-standard plasma torch family. Machine torches (45XP, 65/85/105 XR series) are CNC-mountable.
• Razorweld / Cut45/65 — paid, cheap; budget Hypertherm-compatible torches; common on Langmuir bundles.
• Everlast / PrimeWeld / Hobart — mid-tier; users report mixed reliability.

Nesting / sheet-stock layout

• SheetCAM Pro nesting — bundled in the Pro version.
• Deepnest (deepnest.io) — open source; standalone nesting tool; free and surprisingly capable. Outputs DXF/SVG.
• MyNesting / NestFab / SigmaNEST — paid; industrial; mentioned only.

Pick this if…

• You bought a Langmuir CrossFire: FireControl + SheetCAM, done.
• DIY plasma table, FOSS path: LinuxCNC with QtPlasmaC + Proma Compact THC + SheetCAM.
• DIY plasma table, easy path: Mach3 or Mach4 + plasma plugin + Proma + SheetCAM.
• Production plasma shop: keep your existing Hypertherm + Sensor THC; nest in SheetCAM Pro.
• Budget THC: Proma Compact (best price/performance) or EZ THC.
• Just need to nest some parts: Deepnest, free.