A wax injector makes the wax patterns that every cast piece starts from. A good one gives you the same clean pattern every time. A poor one gives bubbles, short fills and patterns that vary from shot to shot. This guide explains what to look for and which type suits your workshop.
What a wax injector does
The machine melts wax in a heated pot and pushes it into a rubber mould. When the wax cools, you open the mould and take out a wax copy of the design. The patterns then go to stone setting or straight onto a casting tree.
Five things to compare
1. Vacuum
A vacuum injector removes the air from the mould before the wax goes in. For fine jewellery this is essential. Without vacuum, air gets trapped in small details and you get bubbles and missing parts.
2. Temperature control
Look for separate temperature control for the wax pot and the nozzle. The wax should leave the nozzle at the temperature you set, every time.
3. Clamping
Hand clamping changes from one operator to the next. An auto-clamp holds every mould with the same force, which reduces flash and keeps patterns the same.
4. Stored settings
Different moulds need different pressure, vacuum time and hold time. A machine that remembers settings for each mould saves time and stops guesswork.
5. Two-stage injection
The first stage fills the mould. The second pushes in a little more wax as the pattern cools. This reduces shrinkage on thick pieces.
Semsons Tech wax injectors compared
| Model | Main features | Best for |
|---|---|---|
| DVWI-1 | Tabletop, vacuum, auto-clamp, two-stage injection, settings for 10 moulds | Workshops starting with digital injection |
| T4 | Vacuum, auto-clamp, programmable pressure and timers, 3 kg wax tank | Everyday workshop production |
| T4A | 5 litre wax tank, two-stage injection, settings stored for each mould | Longer runs with fewer refills |
| D4 | A chip on each mould loads its settings automatically | Workshops running many different moulds |
| Automatic injector | Automated mould loading, mould identification, recipe for each mould | High-volume factories |
All of them use vacuum and separate pot and nozzle temperature control, run on single-phase power and need a compressed air supply.
How to choose
- A few moulds, small batches: DVWI-1 or T4.
- Long runs, fewer stops to refill: T4A.
- Many different moulds every day: D4.
- Factory volumes with minimal handling: the automatic injector.
Check before you buy
- Is it a vacuum injector, and can you see the vacuum gauge working?
- Are the pot and nozzle temperatures controlled separately?
- Does it have an auto-clamp?
- How many mould settings can it store?
- What compressed air supply does it need?
- Who installs it and trains your operator?
Having trouble with the patterns you make now? Our guide to wax injection defects lists the causes and fixes. Good wax also decides how well an automatic setting machine performs; see why wax quality matters.
Where to see and buy it
These are the Semsons Tech machines for this job. The store links let you book online; the other links open the full specifications or a quotation request.
| Machine and where to buy | Key facts |
|---|---|
| DVWI-1 digital vacuum wax injector Buy or book on our store | Tabletop vacuum injector with auto-clamp Two-stage injection, settings stored for 10 moulds |
| T4 vacuum wax injector Buy or book on our store | Vacuum, auto-clamp, programmable pressure and timers 3 kg wax tank |
| T4A vacuum wax injector Buy or book on our store | 5 litre wax tank for longer runs Two-stage injection, settings stored per mould |
| D4 vacuum wax injector Buy or book on our store | A chip on each mould loads its own settings |
| Automatic robotic wax injection machine Buy or book on our store | Automated mould loading and a recipe for every mould |
See a vacuum injector working before you choose. Book a demonstration or call +91 98216 12340.