Mixing ratio – Wirovest plus
(printed patterns / CAD frameworks)

Lab area: casting bench
Version: v1.0
Last reviewed: 12/02/2026
Next review: 12/08/2026

What this is for

To correctly mix Wirovest Plus investment for printed patterns and CAD frameworks.
Accurate ratios and temperature control ensure correct expansion, strength, and fit of the casting.

You need

Materials

• Wirovest Plus powder (Bego)

• Begosol liquid

• Distilled water

Equipment

• Clean rubber mixing bowl

• Graduated measuring cylinder (mL)

• Digital scale (grams)

• Vacuum mixer [confirm: model used at vNL]

• Timer

• Thermometer (for liquid temperature)

PPE

• Safety glasses

• P2 mask (powder handling)

• Gloves

• Lab coat or apron

Before you start (setup)

• Clean and dry all mixing equipment.

• Check powder bag is unopened and within expiry.

• Bring liquids to 20–22 °C.

• Check vacuum mixer is clean and functioning.

• Confirm number of bags required (1 or 2).

Steps

For 1 bag (400 g powder)

1. Weigh 400 g Wirovest Plus powder.

2. Measure 33 mL Begosol.

3. Measure 27 mL distilled water.

4. Combine liquids to total 60 mL.

5. Confirm liquid temperature is 20–22 °C.

6. Add liquid into mixing bowl first.

7. Add powder to liquid evenly.

8. Mix under vacuum for [confirm: mix time].

9. Release vacuum slowly.

10. Pour investment carefully into ring.

11. Allow to bench set undisturbed for [confirm: bench set time].

For 2 bags (800 g powder)

1. Weigh 800 g Wirovest Plus powder.

2. Measure 66 mL Begosol.

3. Measure 54 mL distilled water.

4. Combine liquids to total 120 mL.

5. Confirm liquid temperature is 20–22 °C.

6. Add liquid into mixing bowl first.

7. Add powder evenly.

8. Mix under vacuum for [confirm: mix time].

9. Release vacuum slowly.

10. Pour investment carefully into ring.

11. Allow to bench set undisturbed for [confirm: bench set time].

Liquid-to-powder ratio

15 mL liquid per 100 g powder

Control liquid precisely.
Warmer liquid → faster set, less working time.
Cold liquid → longer set, slightly higher expansion.

Quality checkpoints (what “good” looks like)

• Smooth, creamy consistency (not runny, not thick).

• No visible bubbles after vacuum mix.

• Ring fills smoothly without trapping air.

• Surface sets firm and uniform.

• No early cracking during set.

• Working time matches expected behaviour at 20–22 °C.

If mix thickens too fast → check liquid temperature immediately.
If surface is chalky or weak → review ratio and mixing accuracy.

Common mistakes + fixes

Liquid measured by eye → expansion errors → always use cylinder.
Wrong temperature liquid → fast or slow set → confirm 20–22 °C before mixing.
Adding powder too quickly → lumps → add gradually and evenly.
Over-mixing → reduced expansion control → stop at confirmed mix time.
Under-vacuuming → porosity → check vacuum seal and duration.
Contaminated bowl → inconsistent set → clean and dry fully before use.

Clean-down + reset

• Discard unused set investment safely.

• Wash bowl and tools immediately before material hardens.

• Wipe down vacuum mixer and bench.

• Return materials to sealed storage.

• Leave station ready for next person.

Escalation

Technical issue (mix inconsistency, vacuum failure) → Carly → Golboo → Garth
Clinical fit concern related to expansion → Garth
System/workflow issue → Eloise or Golboo → Georgie

Record keeping

• Log number of bags used.

• Record liquid volumes used.

• Note liquid temperature if outside 20–22 °C.

• Log any mix variation or issue in ticketing system.

• Record rework linked to expansion or investment behaviour.

Footer:
Version 1.0. Date 12/02/2026. If you change a setting, update this poster and log the change.