Screw and functional cap moulds
A screw closure seals on a thread that somebody else already cut - the neck of the bottle or jar you are already filling. So the tooling starts from that neck, not from a standard, and the sealing lip is cut to sit on it.
- ProcessInjection
- Lead time40–60 days
- CavitiesQuoted to your output
- ThreadCut to the neck you already run
Closures that seal and stay on
Our cap tools at tryout: a 28/410 screw cap above; here, two snap-on overcaps, 40 mm and 45 mm.
See every cap mould we cut, from flip tops and two colour caps to tear-off closures.
Large overcaps
The big screw-on overcaps that go on jerry cans and detergent containers, moulded at eight cavities.
A large overcap has a long thread and a lot of material, so it cools slowly and it warps if the wall and the cooling are not right. It is also the part the customer grips hardest. The one in the drawing is HDPE at Ø59.8 mm, 65.65 mm tall, and it runs eight cavities.
Small screw caps
The small screw caps that close cosmetic, pharmaceutical and food bottles, where cavitation is what decides the price.
Small caps are cheap parts made in enormous numbers, so the whole job is cavity count and cycle. Tell us the neck finish and the caps per hour and the tool is planned around that number, not around a catalogue.
Seven questions about the tool itself
The seven that decide whether you order, answered for this tooling. Where a figure is on the drawing we print it; where it depends on your part we say which numbers we will ask you for.
Hot runner or cold runner?
A standard neck cap in a small tool is usually cold runner; a high cavitation tool for a 28/410 style closure normally goes hot so that every cavity fills alike. The decision is on your part weight and cavity count and is in the quotation.
Cycle time and output
Worked from the cap weight, the wall and the cooling on your machine. Tell us the caps per hour you need and the cavity count and cycle are calculated to it.
How the part is ejected
Screw caps are stripped off the core if the thread can be jumped, and unscrewed if it cannot. Which one your cap needs depends on the thread depth and the material, and the layout is approved with the drawing.
Tryout report and acceptance
The tool is tried here and the caps ship with it. Thread gauge, torque and weight are the points customers usually put on the acceptance list; tell us yours.
Spare parts
Cavities, cores and stripper rings are cut from the original drawings whenever you need them. Tell us the spare sets to pack with the mould.
Warranty
The warranty for that tool is written into its quotation.
Will it fit your machine?
Send the make, model and tonnage. Platen size, tie-bar spacing and ejector layout are checked before the mould is designed.
What we will ask you for: the neck standard or the cap drawing, the cap weight, the material, the output, and the machine.
How many caps an hour do you need?
With screw caps the output also decides how the thread comes off the core — unscrewing or stripping — so it is the first number we ask for.
Tell us your output targetOther closures we cut
Need finished caps instead? Screw caps
Frequently asked questions
More from the same workshop: See all cap moulds · eye dropper outer cap moulds · measuring cup moulds.
Tell us your neck finish
If you know the code — 28/410, 38/400, PCO 1881 — that alone is enough to start. Otherwise measure the outside diameter of the cap and attach a photo.
- ✓The neck finish code, or the outside diameter of the cap
- ✓A drawing, a 3D file, or clear photos of the closure
- ✓Material, and whether it needs a liner or a sealing lip
- ✓Cavities you want, or the machine tonnage, or caps per hour