Vacuum Casting

November 24, 2020

How to manage cost & leadtime for my first batch??

Should I go for Mould ?

Will there by any Design change after first batch from market?

How to manage the mould if there is a design change?

My Market launch quantity is less than 1000 numbers, why should I invest huge amount in mould?

These are all the typical questions which will arise in every New Product Development team’s mind when they plan for first batch production. Obviously Injection moulding will give best quality what we can dream for… But it comes with huge upfront mould cost and refraining us with any Design change.

So…. Is there any solution for producing small quantities like 20 to 100 with flexibility of changing the design or colour after every batch and not paying huge upfront mould cost?

Vacuum Casting can give solutions for all the above queries…

Vacuum Casting is gravity casting process in which Liquid PolyUrathene resin is poured inside a silicon Rubber Mould (Which has the component cavity)  in a vacuumised chamber.

The overall Process included 3 steps:

  1. Master Pattern preparation using 3D Printing
  2. Silicon Mould making
  3. Component production
  4. Master Pattern using 3D Printing

CAD data is the Primary input to this process. CAD data is fed into the Printing software and printability is ensured by providing proper support to the main CAD Model. The Print file generated form the printing software will be sent to the 3D Printing machine. Based on the print file,  Part will be built layer by layer in the 3D Printing machine. Once part is printed, it will be taken out of the machine, Support will be removed and cleaned using cleaning solvents. Subsequently, sanding operation is done to remove the support and make the surface smooth. Finally the surface quality of the part is further enhanced by putting primer and then painting. In this process, CAD data is converted to a Master pattern for mould.

  1. Silicon Mould making

Master pattern is the input to this process. Moulder will plan for the parting line based on the features of the component and functional requirements. Master pattern is prepared for mould making by providing risers, gates, parting line and mould box. Required level of Liquid silicon will be taken, stirring done to get a homogeneous mix and will be kept inside the vacuum casting machine. Then the silicon rubber will be poured inside the mould box to get uniform distribution of silicon in the complex surfaces of the part. Then mould is cured for 14 hours to get a solid mould. Pattern will be taken out from the Silicon mould and the mould is ready with cavity.

  1. Component production

Mould and PU resin is the main input to this process. Mould is preheated before starting the moulding process. Required level of PU resin is taken and kept inside the vacuum casting machine at -1 bar pressure. Then this PU resin poured into the Silicon mould. Then part is taken out and finished and painted.

Written by NextGEN3DTech trusted partner in product development