small run manufacturing

Skills materials and processes
1

I was thinking about products that are made in small quantities (<1000). I think it’s a cool avenue that’s getting more attention from designers. But I’m wondering how does one take that on? and what kind of prices are they looking at for say a small injection molded product?

2

Depends. Tooling can be as low as $5K and parts under $1.

3

Call these guys: http://www.protomold.com/

4

Depends on part size and complexity. Aluminum tooling runs $3-5K and is usually good for 10k parts. Lead time is about 3-4 weeks. I’ve seen quotes for hardened steel tooling under $5k, but i’m not sure I trust them.

5

And depending on the physical size and shot-weight of your widget, there is always the do-it-yourself approach via micro molding machines; i.e. Morgan Industries.

And depending upon the materials, cycle times and production rates, cast epoxy tooling is even an option.

6

There is a place near Chicago called GPI prototyping that can do injection molding using a rubber mold rather than aluminum or steel. You get about 50 pieces out of a roughly $200 mold. Might be an option for you.

http://gpiprototype.com/Services/rtv-tooling-urethane-casting-prototype-production.html

7

TEK Cast has been building metal spin-casting machines that utilize vulcanized organic rubber molds for a long time; the mold surface is quite hard… 60-80 Shore D.

The metal most often used is antimony, pewter, lead, etc. with process temperatures above 500°F; well above thermoplastic range, and probably would work as “molds” in the Morgan machine as well. Cycle times would be long, and pressures would have to be carefully monitored…

8

I’ve looking to do this. Can you just provide your 3d model and they produce it with a at home user friendly way to use the mold.

Also, I’ve been thinking about making a mold like this at home to make about 50 pieces. I have some experience making molds but I do know the basic principles. Any body have a good reference for making something like this? I’m trying to figure if it’s worth the money to avoid the hassle of making my own molds. Any thought?

9

We are a US company and owns and manufacture in China. We do Plush, Vinyl, Resin, Plastic, and wooden toy.
http://www.patchtogether.com/page/Production
Just write us an email at miller@patchtogether.com
We do very small run of toys
Plash: 300
Resin: 50
Vinyl: 500

10

I second this. It is definitely the path of least resistance. Just upload your CAD file and they will automatically tell you what’s wrong with it, how much the mold will cost, and the piece part cost.


These are not true injection molded parts, they are urethane castings. This is usually good for prototypes that you want to test before going to production, but that’s about it. Urethane casting’s try to emulate thermoplastics, but their chemical resistance, durability, precision (especially precision) aren’t up to snuff.

11
12

one of the big problems with using silicon molds at home is that you probably don’t have a pressure chamber - modelshops use them to squeeze all the air bubbles in the hardening resin into tiny imperceptable bubblets that can’t cause problems.

Other than than, making a home silicone mold is fairly straightforward, just a bit of a learning curve. At a startup position once, we hired a modelshop to train one of our guys in the techniques of RTV silicon molding. From the pics he took, it didn’t look that hard, just a little thought needed to plan how to mold each part. PS - these usually get 20-50 parts per mold.