Gravity Die Casting Services | Leesh Holdings
Leesh Holdings provides gravity die casting services for buyers who need dependable aluminum castings – cast, machined, inspected and documented in one plant. Send a 3D model or a 2D print, and our engineers take the part from tooling design to serial production under one roof, with as-cast accuracy controlled to ISO 8062 CT4-CT6.
One Gravity Die Casting Process, Controlled End to End
Our gravity die casting process uses steel permanent molds on tilting machines: molten aluminum fills the die under gravity alone – there is no high-pressure injection – so castings solidify with a fine, dense grain structure and very low porosity. Resin sand cores set inside the die create internal channels that plain permanent molds cannot form. Where the drawing calls for it, parts are heat treated to T5 or T6 and then finished on our own CNC lines.
The Route from Drawing to Delivery
- Tooling design and casting simulation for feeding and solidification
- Die coating and preheating to control the cooling rate
- Melting and degassing – melt chemistry checked before every pour
- Tilting gravity die casting, with resin sand cores where the design needs internal channels
- Trimming, flash and burr removal, and heat treatment (T5 / T6)
- CNC machining, cleaning and final inspection
Inside Our Die Casting Foundry
Four stations decide most of the casting quality – melting, core assembly, trimming and machining. Ours sit on one production line, so nothing that affects your gravity cast aluminum parts is outsourced.




Quality Control, Measured Not Claimed
Casting tolerances follow ISO 8062, VDG P690 and GB/T 6414 – this part family is controlled to CT4-CT6 as cast. Inside defects are screened by X-ray, dimensions by CMM, and contours and surface roughness on dedicated measuring machines. Material, dimension, performance, inside-defect and balance test records travel with the shipment on request.


Alloys and Standards We Pour
Typical gravity casting alloys include the AlSi7Mg family (A356.0 / EN AC-42100 / ZL101A), AlSi10Mg (ZL104), eutectic AlSi12 (LM6 / ZL102) and the Al-Si-Cu grades (355.0 / 319.0 / ZL105A), poured against ASTM, DIN, JIS, ISO and GB standards as the order requires. The final alloy and temper are always specified per customer requirements – send the standard you work to and the castings arrive certified to it.
Capabilities at a Glance
| Item | Capability |
|---|---|
| Processing | Casting + machining |
| Material | Aluminum (alloy per drawing) |
| Weight | According to the part drawing |
| Tolerance | Controlled by ISO 8062 CT4-CT6 |
| Design support | Pro-E, UG, SolidWorks, AutoCAD, PDF |
| Quality control | Material, dimension, performance, inside defects, balance test |
| Standard | ASTM, DIN, JIS, ISO, GB standards |
A Look at Our Gravity Cast Products




Why Buyers Choose Leesh Holdings
- One plant, full route – melting, casting, trimming, heat treatment, machining and inspection under one roof
- Design support – Pro-E, UG, SolidWorks, AutoCAD and PDF drawings reviewed for castability before tooling
- Verified quality – X-ray for inside defects, CMM for dimensions, balance test for rotating parts, documents on request
- Standards coverage – ASTM, DIN, JIS, ISO and GB tolerance and material standards
- Volume flexibility – permanent mold tooling carries prototypes, pilot lots and annual programs on the same route











