A structural fab shop needed to quote cutting 14 bracket parts from a 24"×36" A36 carbon steel plate at ½" thick using their high-definition plasma table. The estimator used IronKit's CNC Cut Time & Cost Calculator to get a full cycle time breakdown and per-part cost before finalizing the quote. At 80 IPM feed rate and 14 pierces, the plasma table completes all 14 parts in under 3 minutes of total cycle time. The cost breakdown showed piercing adds 7 seconds total — negligible on plasma, which is the right machine for this material and thickness. Waterjet would have been 4× slower and 3× the cost on this job.
Frequently Asked Questions
Why is HD plasma the right process for ½" carbon steel at this volume?
HD plasma cuts ½" A36 at 80 IPM — roughly 8–10× faster than waterjet on the same material. At $72/hr shop rate, you get $0.16/in on plasma vs. $0.55–$0.80/in on waterjet. Fiber laser can match plasma speed on ½" but the capital cost of a laser table is 3–5× more, so the breakeven hourly rate is much higher. Oxy-fuel is cheaper on very thick plate (>2") but slow and imprecise at ½". Plasma wins on all three counts for this job.
What if pierce count is higher — say 28 pierces instead of 14?
On plasma, pierce time is 0.5s × 28 = 14s total — still under 10% of cycle time. Piercing is not the bottleneck on plasma. On waterjet, 28 pierces × 5s = 140s, which is more than the actual cut time — so piercing becomes 44%+ of total cycle. This is why pierce count matters most for waterjet quoting, and less for plasma.
How does IronKit calculate cut time per inch?
Cut time = cut length ÷ feed rate (IPM). Lead-in/out time = (lead-in + lead-out per pierce × pierce count) ÷ feed rate. Pierce time = pierce count × pierce time per pierce. Rapid time = rapid distance ÷ rapid rate. All four phases sum to total cycle time. The calculator auto-suggests feed rates from process + material + thickness using Hypertherm reference tables, but you can override with your machine's actual performance.
What consumable cost rate should I use for plasma?
For HD plasma, electrode and nozzle life of 1–3 arc-hours each at $8–18/set gives $6–18/hr amortized depending on your consumable prices and cutting conditions. The calculator defaults to $12/hr for HD plasma — a reasonable mid-market number. Check your actual electrode cost ÷ life in hours and enter your real number for accurate costing.