Changing a bronze model without new tooling

Most changes buyers ask for do not need a new mould. A different patina, your lettering on the base, a motif left off, a plain lid instead of a pierced one — those run on the model we already have. Scaling a piece to a new height, changing the silhouette or thickening the wall starts new tooling. Which side your change falls on decides whether you are three weeks from a lot or starting from a model.

Which changes cost nothing and which need a new mould?

Lost wax works in two stages. A master model gives us wax copies, and every wax is dressed by hand before investment. Anything done in the wax, or on the metal afterwards, rides on the master we hold. Anything that changes the form means a new master, because a wax cannot be stretched, thickened or re-profiled.

That line is the whole decision. Removing a decorative band is wax work; making the same piece 10 cm taller is a new model.

Can a size be scaled, or does each size need its own model?

Each size is its own model. A wax does not scale, and wall and weight do not grow at the same rate as height.

A Vietnamese altar set is also a ladder: cranes stand 5–7 cm taller than the incense burner, candlesticks sit 12–15 cm below it, and the incense bowl is about one third of the burner's height. Change one piece and the set stops reading correctly, so ask for a size rather than a percentage. Nominal names are not measurements either — our "60" burner stands about 57 cm under a tape. The whole ladder is in reading a Vietnamese altar set.

Can lettering, a logo or a motif change on a model we already have?

Yes, and it is the change buyers ask for most. It is worked into the wax before investment, so the piece carries it as cast rather than engraved afterwards — which is why it costs no tooling and why it must be right before the wax is finished.

Send typed text rather than a photograph of handwriting, with Vietnamese diacritics in a file we can copy, and name one person who approves the proof. Hand work varies, so letter placement moves slightly within a lot. What a usable artwork file looks like is set out in how to send a drawing for a bronze casting quote, and the script itself in casting Vietnamese and Chinese text in bronze.

What about the base, the lid and the handles?

Base height moves a few centimetres in the wax; a different footprint does not. A pierced lid can usually be closed up, but a lid of another shape is a new part. Handles are the useful case: a different handle is its own small model rather than a new master for the body, so ask about the handle on its own.

Wall thickness needs care. We cast at 5 mm, and 8 mm where a piece takes load — handles, feet, the lid knob. A heavier wall means a new model and a heavier piece: a size 65 five-piece set already runs about 36 kg, which reaches your crates before it reaches your shelf.

How do I ask so the answer comes back in one round?

Put all of it in one message:

1. The model you are starting from — our item name, or a photo from custom and OEM casting.
2. A photo marked up with every change, one note per change.
3. The finished dimension that must hold, and where it is measured from.
4. Text or artwork in final form, not a draft.
5. Quantity now, and the quantity you expect to reorder.
6. Whether all sizes in the order must match each other in tone.
7. Who approves the proof on your side.

We answer a complete request within two working days and say which changes ride on the existing model and which need a new one. We do not publish mould time or cost: both depend on the piece, and we only give numbers the floor has confirmed. Casting runs 21–30 days from an approved sample, and a change made in the wax does not lengthen it; a new model is quoted separately. More on model work is on OEM and tooling.

What do I get to keep when I pay for a change?

Whatever is written down. If you pay for a new model, settle in the order who holds it, whether we may cast it for others, and what happens if you stop ordering. Those answers differ between foundries — ours are set out in who owns the mould.

Two limits worth stating. We have no ISO or BSCI file, so an agreement about a model is a written agreement, not a certified process. And repeat lots off one model still vary: 1–3 cm is normal on hand casting, over 5 cm is a fault we put right at our cost — see tolerances in hand casting. If your buying agent is in Vietnam, the model can be seen in the hand; we keep showrooms in Nam Dinh, Hanoi and Hai Phong.

Questions buyers ask

Does changing the size mean a new model?

Yes, apart from a few centimetres of base height. Each size is cast from its own master, so a new height is a new model even when the shape is unchanged.

Can you add my logo to a piece you already make?

In most cases, worked into the wax. Send a vector outline and say which face it sits on; very fine lines may need simplifying, and we show you that before the wax is finished.

If you change a model for me, can another buyer order it?

That depends on what the order says. Ask in writing either way — exclusivity on a model you paid for is a normal request, better agreed at the start.

How fast do I know whether a change needs tooling?

Within two working days of a complete request. A marked-up photo and one fixed dimension are usually enough for a straight answer.

Will a changed piece match a lot I ordered before?

In form, yes, if the change was made in the wax off the same master. In tone, only if the finish was recorded — ask for it by name when you reorder, and expect 1–3 cm of normal variation.