Usually Many End up in Loss while choosing in between 3d printing & Plastic Injection Molding to use for their Product Manufacturing.

Plastic material generally used are ABS, PP, PS, PC, HDPE, LDPE, Acrylic. For respective applications, matching plastic materials will be used. Its better to go with Plastic Injection Molding for quantities more than 100. If the quantity is less than 100, better to go with 3D Printing. But 3D printing finishing is not promising as the finishing of injection molded product. So if the finishing is not matter and less time of Days & Low Quantities, Best to go for 3D Printing.

If You want fine smooth finish, and Have good timeframe like 30 days for any quantity, Best to go for Plastic Injection Molding. There are Mold Cost and Production Cost per unit separately in case of plastic Injection Molding. because there might be 500% difference in cost between 3d printed production cost to plastic injection molding production cost.

So If you have Low Quantity, Money is not matter, Less time, Finishing is not required, Best to go for 3D Printing.

If You have Batch or Bulk Quantities, Plenty of time at least 30 days, good Finishing is required, Best to go for Plastic Injection Molding.