VIETNAM GLOBAL HEALTH - VISIT TO AN INJECTION MOLDER

We started our first day in Hanoi with a trip to a local mold maker & an injection molding contractor. The goal was to investigate their facilities and estimate the likely cost of manufacturing our plastic user interface housing for the Otter newborn warmer. The photo below shows the team attaching the white, plastic user interface to our warming bassinet.

How many engineers does it take to drill a hole? Answer: Chloe Nguyen (MTTS), Hoa Dang Thanh (MTTS), Maire Keene (ADE) and Liani Lye (ADE).

There are many options for how to make a plastic part. As the quantities increase, injection molding can become a cost-effective way to make many identical parts with complex geometries. Design that Matters’ manufacturing collaborator, MTTS, suggested a vendor nearby in Hanoi might be able to make our part for an affordable cost.

At the mold-making shop, we spoke with Lai Duc Khoa who reviewed our CAD model and the 3D-printed part we made. We learned about the importance of working with manufacturing vendors close to MTTS in Hanoi to better ensure quality and keep costs like importation fees low leading to lower part costs.

Chloe Nguyen (MTTS Engineering Fellow) translates our questions for Mr. Khoa, a potential plastic injection mold-making vendor.

Duc (MTTS) and Maire Keene (ADE) standing near the CNC machines that make injection molding tools.

The mold maker uses CNC (computer numeric control) machines to create the mold; negative impressions of the inside and outside of a plastic part. The mold for our part would likely be made from steel. This vendor would then give the mold to a subcontractor. To create a plastic part, the subcontractor would fit the mold inside a press that holds the two pieces together while hot, liquid plastic is injected into the cavity formed by the two pieces. We visited one of the sub-contractors who was using one of the molds to create a Mickey Mouse toy.

The negative and positive sides of an injection mold for a mickey mouse toy!

Extra pieces of plastic such as the gate are trimmed from the toy by hand.

It looks like these vendors could be a good option for molding our part. The price estimates are a little higher than we planned, but would only add a few dollars to the price tag of our medical device.

Many thanks to Nguyen Duc Viet, MTTS Mechanical Engineer and Chloe Nguyen, MTTS Engineering Fellow, for setting up this visit, providing insight on how to select a vendor, and for bridging the language gap.

Author: Maire Keene