How does casting yield change the metal cost?

Poured weight is casting weight divided by yield. An 18.5 kg casting at 62 percent yield needs 29.84 kg poured, of which 11.34 kg is gating and risers. Those returns go back into the melt, so with a 100 percent return credit you lose only their melt loss and energy. In the example the metal costs 17.99 per casting poured; at 70 percent yield it would fall to about 17.58.

How are melt loss and melting energy included?

The cost of liquid metal is the charge price divided by one minus the melt loss, plus kWh per kg times the electricity price. Ductile iron at 0.78 per kg with 4 percent melt loss and 0.62 kWh/kg at 0.14 per kWh costs 0.78 / 0.96 + 0.62 x 0.14 = 0.899 per kg of liquid metal.

Why are some process steps timed per mould?

Moulding and pouring work on whole moulds. With two castings per mould, 1.5 minutes of moulding is 0.75 minutes per casting. Shakeout, fettling, heat treatment and inspection are usually timed per casting. The Per column decides which applies to each row.

How is the pattern cost spread?

Purchase plus engineering, less residual value, times the share charged to this part, divided by the accepted castings expected over the pattern's life, as in the Pattern Cost Amortization calculator. In the example (14,500 + 2,200 - 0) x 100 percent / 3,000 castings is 5.57 per casting at every order size.

Why is the price higher for small orders?

Setup is per order: here 0.75 hours on the moulding line for the pattern change and 0.5 hours of core box setup, 162.50 in all. That adds 8.13 per casting on 20 castings but 0.33 on 500. First-pass yield also rounds up: 20 good castings need 22 poured at 94 percent yield.

Does it agree with the Casting Lot Cost calculator?

Yes. The calculator returns (castings started x variable cost per started casting x allocation + setup + rework) / accepted castings. This workbook builds those inputs from the metal, cores, process steps and pattern, and the build checks the result for the example order of 100 against the calculator's engine, along with the calculator's own example (240 started, 228 accepted: 71.37 per accepted casting).

Industry Cost Kits

Casting Cost Estimator Excel Template

Cost a casting from the metal poured for it, melt loss and melting energy, cores, the process steps from moulding to inspection and the pattern, and price five order quantities.

Overview

This casting cost estimator is an Excel quoting tool for jobbing and production foundries and for buyers who want to check a casting price. It ships with a worked example for a fictional foundry, an 18.5 kg sand-cast ductile iron gearbox housing, two to a mould with two cores each, priced at orders of 20 to 500 castings.

Metal is costed the way a foundry melts it. The casting weight divided by casting yield is the poured weight; the difference is gating and risers that go back into the melt. Liquid metal costs the charge price divided by one minus the melt loss, plus melting energy at your electricity price, and the returns are credited at the share of the charge price you set. Cores are a cost per core, and each process step from moulding to inspection is timed per mould or per casting, so the castings per mould share the moulding and pouring time.

Scrapped castings are remelted and repoured through first-pass yield, setup is spread over the order, the pattern is amortised over the castings you expect over its life, and overhead and your target margin on price give a price per casting rounded to your step. The Dashboard shows the order you pick with the price per kg, two charts and the cost build-up. The order cost has the same form as the Casting Lot Cost calculator on this site, and the build checks it, the Casting Yield and the Pattern Cost Amortization calculators against their engines.

What this template includes

Metal block: casting weight in kg or lb and casting yield give poured weight and returns; charge price, melt loss and melting energy give the cost of liquid metal, with a credit for remelted returns
Alloy data and work-centre rates on Setup, with charge prices per kg or per lb
Castings per mould and cores per casting at a cost per core
Process table from moulding and pouring to fettling, heat treatment and inspection, timed per mould or per casting, with setup per order
Pattern and core boxes: purchase plus engineering, less residual value, times the share charged, over the castings expected
Five order quantities with castings to pour for your first-pass yield, every cost line, overhead, margin on price, a rounded price and metal to melt
Dashboard for the quantity you pick: price per casting and per kg, cost, margin against target, poured weight, two charts and the cost build-up
Verify sheet that recomputes poured weight, metal cost, process steps, pattern and the price build-up on fixed inputs against an independent reference

Suggested use case

Use it to quote a new casting, to see what a better casting yield or a lower melt loss is worth per casting, and to check how pattern cost and order size move the price.

How to use it

On Setup, type your company name, currency, electricity price, return credit, overhead, margin, first-pass yield and price step, then alloy data and work-centre rates.
On Casting Estimate, choose the alloy, enter the casting weight and casting yield.
Enter castings per mould and the cores, then list the process steps with minutes per mould or per casting and setup hours.
Enter the pattern cost, engineering, residual value, share charged and expected castings, and type five order quantities.
Read cost, price per casting, margin and metal to melt; on the Dashboard, pick a quantity to see the tiles, charts and cost build-up.

Frequently Asked Questions

How does casting yield change the metal cost?: Poured weight is casting weight divided by yield. An 18.5 kg casting at 62 percent yield needs 29.84 kg poured, of which 11.34 kg is gating and risers. Those returns go back into the melt, so with a 100 percent return credit you lose only their melt loss and energy. In the example the metal costs 17.99 per casting poured; at 70 percent yield it would fall to about 17.58.
How are melt loss and melting energy included?: The cost of liquid metal is the charge price divided by one minus the melt loss, plus kWh per kg times the electricity price. Ductile iron at 0.78 per kg with 4 percent melt loss and 0.62 kWh/kg at 0.14 per kWh costs 0.78 / 0.96 + 0.62 x 0.14 = 0.899 per kg of liquid metal.
Why are some process steps timed per mould?: Moulding and pouring work on whole moulds. With two castings per mould, 1.5 minutes of moulding is 0.75 minutes per casting. Shakeout, fettling, heat treatment and inspection are usually timed per casting. The Per column decides which applies to each row.
How is the pattern cost spread?: Purchase plus engineering, less residual value, times the share charged to this part, divided by the accepted castings expected over the pattern's life, as in the Pattern Cost Amortization calculator. In the example (14,500 + 2,200 - 0) x 100 percent / 3,000 castings is 5.57 per casting at every order size.
Why is the price higher for small orders?: Setup is per order: here 0.75 hours on the moulding line for the pattern change and 0.5 hours of core box setup, 162.50 in all. That adds 8.13 per casting on 20 castings but 0.33 on 500. First-pass yield also rounds up: 20 good castings need 22 poured at 94 percent yield.
Does it agree with the Casting Lot Cost calculator?: Yes. The calculator returns (castings started x variable cost per started casting x allocation + setup + rework) / accepted castings. This workbook builds those inputs from the metal, cores, process steps and pattern, and the build checks the result for the example order of 100 against the calculator's engine, along with the calculator's own example (240 started, 228 accepted: 71.37 per accepted casting).