Category:Diecast metal toys
The diecasting process involves injecting molten metal (usually a zinc-based alloy) into a mould made from hardened (usually tool-grade) steel. Diecasting became a significant feature of British toymaking with the introduction of Dinky Toys in the mid-1930s, cast using the recently-developed Mazac zinc alloy.
- High casting pressures allow high detail
- High casting pressures allow the use of "sludgy" metal alloys
Diecasting has certain limitations:
- The use of tool-grade steel makes the dies very expensive, so the process is most suitable for the mass-production if large numbers of identical parts - if making huge numbers of a piece, the initial cost of the die becomes less important. This makes diecasting very much an "industrial" process.
- There is typically a maximum size that can be cast per "shot", which limits the size of parts, and also the number of smaller parts that can be cast per "shot".
- The shapes of parts need to be reasonably simple to make it easy for the cast pieces to detach from the mould
- The process usually results in tiny amount of trapped air inside the final piece ("porosity"), which prevents further heat-treating processes (such as case-hardening) being applied to the parts, as this would encourage the tiny pockets of air to expand and form micro-cracks in the metal.
Some manufacturers had early problems with the disintegration of zinc alloy diecast items ("Zinc pest") caused by additional "foreign" metals ending up in the alloy before casting ... but these were solved by improved quality control.
Diecasting usually involves non-ferrous metals, to limit metal migration between the melt and the tooling.
Diecasting usually involves the use of channels in the die to guide the liquid metal to the cavities for multiple parts, which then energe connected together by "sprues" or "runners" similar to those found in injection-moulded plastic model kits (eg traditional Airfix kits). In a variant called heated-manifold direct-injection die casting, the die has separate heated inlet nozzles for each chamber in the die, which reduces the amount of waste metal.
The properties make diecasting ideal for the production of smallish "chunky" toy vehicle bodies, where the castings don't have to have any particularly demanding properties, other than the ability to hold high levels of detail, to support thinnish window-frame details, to be able to hold springy steel axles, and to be able to be thudded repeatedly into furniture without cracking.
Prior to the appearance of diecasting, British cast metal toy vehicles were typically made from lead. Lead casting was a well-understood process but resulted in soft castings that might have trouble coping with being stood on, and had "weak" detailing – window frames and bumpers were prone to bending and breaking, wheels were prone to bucking and bending. The softness of the body metal meant that special care was needed when designing how wheels attached to springy steel axles, and how the axles attached to the body.
In the United States, some manufacturers of early metal toys in the late C19th and early C20th used cast iron as a material (eg for the bodies of toy railway locomotives).
This was again a known ("low-tech") material, but resulted in toys that were very heavy, somewhat crude and clunky, and had a tendency to break if dropped onto a hard surface, due to the brittleness of the material
For very small production runs, smaller companies might use "white metal" casting. This typically involves using very low melting-point metals and gravity-fed (or centrifugally fed mould made from special vulcanised rubber). White metal casting was typically only used by specialist "one-man" manufacturers producing low production run products such as niche metal kits.
The rubber moulds are far cheaper to make, but have very restricted lifespans: once a "cottage industry"'s products become popular it often becomes worth the company migrating their designs to diecasting (or plastic injection moulding).
Plastic injection moulding
After World War Two, the injection moulding of plastics became popular for lightweight toys where strength wasn't an issue.
The production of small cast lead figures typically migrated from lead to plastic, as the additional strength of diecast alloys wasn't needed. Diecasting is still popular for small robust toy vehicles, and for larger vehicle models where some detailing may be plastic, but the rigid bodyshell uses diecast metal, typically painted to take a high-gloss finish.
Modern diecast toy vehicles typically also incorporate a variety of plastic parts, for windows (where transparency can't be recreated in metal), for seating and upholstery (where the soft appearance of plastic can add realism), and for fine protruding complex details. Moulded windscreen wipers flex when made from plastic where a metal casting would tend to break off at the root, and complex three-dimensional radiator grilles can often be injection-moulded in plastic and successfully extracted from the moulds due to plastic's flexibility, where an attempt to make the same shape in metal would result int the part and its mould ending up locked together.
This category has the following 10 subcategories, out of 10 total.
- ► 100 Years of Southdown (display) (11 P, 13 F)
- ► Corgi Toys (2 C, 26 P, 39 F)
- ► Dinky Toys (26 C, 179 P, 494 F)
- ► Hornby Dublo (16 C, 107 P, 360 F)
- ► Lone Star (4 C, 1 P, 45 F)
- ► The Spot-On Collection (display) (11 P, 7 F)
Pages in category ‘Diecast metal toys’
The following 14 pages are in this category, out of 14 total.
- Bedford oil tanker truck (Spot-On)
- BMW Isetta bubble-car, bright red, LTR 145 (Spot-On 118)
- BMW Isetta bubble-car, dark blue, JPO 113 (Spot-On 118)
- BMW Isetta bubble-car, dark red, LXQ 216 (Spot-On 118)
- BMW Isetta bubble-car, green, JPO 113 (Spot-On 118)
- BMW Isetta bubble-car, light mauve (Spot-On 118)
- BMW Isetta bubble-car, yellow, CMO 118 (Spot-On 118)
Media in category ‘Diecast metal toys’
The following 32 files are in this category, out of 32 total.
- AEC Mammoth Major 8, with flat float with sides, Spot-On Models 110-3 (SpotOn 1959).jpg 2,272 × 1,070; 704 KB
- AEC Mammoth Major 8, with flat float, Spot-On Models 110-2 (SpotOn 1959).jpg 2,207 × 1,017; 571 KB
- Armstrong Siddeley Sapphire 236, Spot-On Models 101 (SpotOn 1959).jpg 2,277 × 1,213; 743 KB
- Aston Martin DB3, Spot-On Models 113 (SpotOn 1959).jpg 2,123 × 1,029; 549 KB
- Austin Healey 100-Six, Spot-On Models 105 (SpotOn 1959).jpg 1,879 × 940; 440 KB
- Bentley Four-Door Sports Saloon, Spot-On Models 102 (SpotOn 1959).jpg 2,506 × 1,191; 857 KB
- BMW Isetta, Spot-On Models 118 (SpotOn 1959).jpg 1,271 × 969; 342 KB
- ERF 68G, with brick load, Spot-On Models 109-2B (SpotOn 1959).jpg 2,211 × 1,001; 751 KB
- ERF 68G, with flat float with sides, Spot-On Models 109-3 (SpotOn 1959).jpg 2,245 × 991; 643 KB
- ERF 68G, with flat float, Spot-On Models 109-2 (SpotOn 1959).jpg 2,264 × 1,019; 545 KB
- Ford Zodiac, Spot-On Models 100 (SpotOn 1959).jpg 2,248 × 1,021; 565 KB
- Garage (Tri-ang Spot-On Models).jpg 800 × 534; 345 KB
- Jaguar XK SS sports car, Spot-On Models 107 (SpotOn 1959).jpg 1,852 × 871; 432 KB
- Lorries (Tri-ang Spot-On Models).jpg 800 × 534; 297 KB
- MGA Sports Car, Spot-On Models 104 (SpotOn 1959).jpg 1,933 × 872; 455 KB
- Only Spot-On models have All these features (SpotOnCat 1stEd).jpg 1,200 × 957; 152 KB
- Ovaltine bus (Tri-ang Spot-On Models).jpg 800 × 534; 274 KB
- Rolls Royce Silver Wraith, Spot-On Models 103 (SpotOn 1959).jpg 2,581 × 1,179; 768 KB
- Royal Occasion with Tommy Spot, Spot-On 806, (SpotOnCat 7thEd).jpg 1,600 × 1,001; 385 KB
- Spot-On Models by Tri-ang, catalogue cover, First Edition (SpotOnCat 1stEd).jpg 1,600 × 1,272; 397 KB
- Spot-On Models, An Introduction (SpotOnCat 1stEd).jpg 862 × 683; 123 KB
- Spot-On Models, catalogue rear cover, First Edition (SpotOnCat 1stEd).jpg 1,200 × 944; 250 KB
- Spot-On models, clear window packaging (SpotOnCat 5thEd).jpg 1,384 × 1,600; 320 KB
- Spot-On, catalogue cover, 7th Edition, ~1967 (SpotOnCat 7thEd).jpg 1,600 × 993; 297 KB
- Spot-On, catalogue cover, rear (SpotOnCat 7thEd).jpg 1,600 × 991; 315 KB
- Triumph TR3 sports car, Spot-On Models 108 (SpotOn 1959).jpg 1,836 × 872; 466 KB