Every casting
starts with
a split.
Pattern halves separate. Sand packs tight. Molten aluminum fills the cavity you designed this morning. Short-run housings, reverse-engineered brackets, prototype geometries — shipped before your competitor finishes their RFQ.
Five stages. Zero shortcuts.
Descend through the mold — from the pattern shop floor to the shakeout that reveals your part. Each stage is a decision point where sand casting earns its place.
Pattern Shop
The geometry begins here
Your CAD geometry becomes a wood, urethane, or aluminum pattern — split along the parting line. Loose pieces handle undercuts without EDM wire or 5-axis setups. Pattern cost: $400–$2,000 depending on complexity. Reusable for every subsequent run.
Pattern halves — cope side and drag side — are the only tooling investment you make.
Sand Preparation
Silica + binder + compression
Green sand (silica, clay, water) or chemically-bonded no-bake sand packs around the pattern under controlled pressure. Permeability is dialed in: too tight and gas can't escape; too loose and the mold collapses. This is the craft that makes or breaks dimensional stability.
Sand is recycled, reconditioned, and reused — not a disposable cost.
Mold Assembly
Cope meets drag at the parting line
Core boxes produce hollow features impossible to machine economically. Cores are set by hand — calloused fingers placing silica forms into drag impressions with 0.010" clearance. Cope locks down. The cavity is sealed. This takes 12 minutes for a simple housing.
No hydraulics, no clamps, no capital equipment — gravity and sand do the work.
The Pour
CRITICAL STAGE1,300°F aluminum at 45 lbs/sec
Molten aluminum at 1,300°F enters the pouring basin, drops through the sprue, splits at the runner, and fills the cavity in 3–12 seconds depending on part weight. Risers feed shrinkage. Vents release gas. The pour is the shortest step and the most irreversible.
The pour channel is already designed into your gating system — no last-minute improvisation.
Shakeout & Finishing
Sand falls away. Casting revealed.
After solidification, the mold is broken apart — the satisfying crack of a shakeout revealing a clean casting underneath. Gates and risers are cut off. Shot blast removes residual sand. Secondary machining (if specified) brings critical surfaces to print tolerance.
First article inspection report included with every new part number.
Sand isn't the primitive option.
It's the smart option for the right geometry, the right volume, and the right timeline. Select a comparison to see where sand wins — and where it doesn't.
Verdict: Sand casting wins for prototypes, short runs, large parts, and any geometry that might change.
Ready to compare your specific part?
Upload your drawing. We'll tell you exactly where sand wins for your geometry.
What we can pour.
Four alloy families. One process. No volume minimums.
No machine tonnage limit
±0.005" with secondary machining
Pattern + mold + pour + inspection. No 8-week die tool queue.
0.250" for iron and bronze
Ra 63–125 μin with secondary machining
No volume commitment. Order one prototype. Scale when ready.
Engineers who chose sand.
Three problems. Three timelines. One process that delivered.
“We needed a reverse-engineered pump bracket by Thursday — the original OEM part was discontinued in 2008. Foundry had a casting in hand by Wednesday. The CMM report matched our scan data within 0.018".”
“Our housing geometry had three internal passages and a 0.200" minimum wall. Investment casting wanted 8 weeks and $18,000 in tooling. Foundry quoted $1,400 pattern cost and 10 days. We ordered 35 pieces. Perfect.”
“We were prototyping a cast geometry before committing to permanent mold. Three design iterations over six weeks. Sand casting let us change the core geometry between runs for $280 per change. Permanent mold would have locked us in after iteration one.”
Compare your part.
Not a generic RFQ.
Tell us what process you're currently comparing against. That's the question that matters. Our engineers will respond with a direct cost and lead time comparison — not a brochure.
We review your drawing or STEP file — usually within 2 hours during business hours.
We quote pattern cost, per-piece price, and lead time against your named alternative.
You decide. No follow-up calls unless you ask for them.