Injection molding!

In reply to Keith Tanner :

D'oh!  So much for my idea of cornering the FB door pull cups market.

You could try Decatur mold tool & eng in North Vernon IN. I wored for them a while ago. They do good work. The only problem is back then they were moving towards larger tooling but just before I left they started a molding plant and were making all sizes of parts.

A couple of nuances that I haven't read anyone bring up yet.

1) Desired unit cost.

2) Tolerance requirements.

Protolabs is great at making things quickly but will their unit cost be acceptable for what you are trying to do in the market? Rough rule of thumb: Prototype CNC machine or 3Dprint will have highest unit cost, Protolabs stuff slightly lower, production CNC lower still, injection molding the least cost.

Protolabs (at least on the CNC machining side) has a "you take what we make" policy and their control (or lack thereof) of tolerances may not be what you want. If the part is cosmetic you will be fine. If the part is going in a motor or being used for brain surgery Protolabs will not be your long term solution.

We do not recommend the use of any Flyin' Miata parts in brain surgery :)

My initial question - where is the crossover point between 3D printing and injection molding? - has been answered by Protolabs. For the quality of 3D print we'd require and if we use them, we're right on it. 

Which is good, it means I asked the question at the right time.

Desired unit cost: less than the cost of 3D printing the item. If it's more, then printing is the right solution. If it's less, then we can bring other factors into the equation. In our experience, the printer is less expensive than production CNC. Of course, this varies dramatically based on the design. It's also worth noting that, in my experience, CNC production is one of the most problematic when it comes to surprise outages or quality screwups.

In reply to Gingerbeardman :

I was going to ask if just casting based off of 3d printed molds would be an option. 

There is a cat who posts on Pelican that makes rubber 914 stuff, seal for the bottom of the windshield, rubber doo dads that that hold the targa top in the trunk, random NLA types stuff.  He does it more as a hobby than to make any money off it though.

What is it you are trying to get manufactured?

I'm not willing to share that information at this point.

Toebra said:

What is it you are trying to get manufactured?

You remember those cheap wax mold toys you can get at theme parks or zoos? He wants to make limited edition scale Miatas like that. 

Keith Tanner said:

Thanks, Gingerbeardman. We don't have the in-house capability to manufacture, unfortunately. 
 

There really is no "manufacturing" capacity needed...the second link I provided is a desktop unit, and molds only occupy a space as big as a stack of CD-ROM cases. It's literally a plug 'n' play operation, other than mixing and pouring the 2-part molding component for the mold. 

Just trying to help.

bluej said:

In reply to Gingerbeardman :

I was going to ask if just casting based off of 3d printed molds would be an option. 

It absolutely is! Barrier-to-entry price points are plummeting as technology and the "maker" movement spreads.

I recently purchased an SLA printer for sub-$300 that prints better than a $300K+ printer from the early 2000's. Fine details are amazing and finishing involves nail files and a UV lamp. 

A little bit of knowledge and a decent amount of gumption can really open doors for a micro-business, or even a larger business with a niche product idea.

Oh, I appreciate it. But we are totally strapped for people here and no, we can't just hire more. There is no broom pusher. Mixing/pouring/cleanup/finishing and dedicating someone to doing that for a couple of days - that's manufacturing. The 3D printer farm is about as far as we want to go in that direction, and those are printers that require no finishing work at all (Markforged Onyx One). I know, there's potential money to be made by being a manufacturer but let's just take that as a constraint.

It's been enough of a challenge distracting our R&D guy long enough to put in a quote request with Protolabs.

Keith Tanner said:

Oh, I appreciate it. But we are totally strapped for people here and no, we can't just hire more. There is no broom pusher. Mixing/pouring/cleanup/finishing and dedicating someone to doing that for a couple of days - that's manufacturing. The 3D printer farm is about as far as we want to go in that direction, and those are printers that require no finishing work at all (Markforged Onyx One). I know, there's potential money to be made by being a manufacturer but let's just take that as a constraint.

It's been enough of a challenge distracting our R&D guy long enough to put in a quote request with Protolabs.

Hmmm...what's your budget? No need to answer here, is there a PM function?

There has to be a vendor option that is lower-cost than Protolabs yet is responsive enough to your requirements. JIT manufacturing and supply is something I'm very familiar with, as a lot of companies don't want more inventory than necessary due to taxes in certain states.

Protolabs has served their function of showing that not every mold is a $50k investment. They came in closer to $3k. So that's opened up injection molding as a legitimate option and we'll continue to pursue it.

We don't need JIT in this case, I'm thinking that a full year's worth of this product would add something like 0.25% to our inventory value :) But the speed of 3D printing would actually be a limiting factor, as the printer would have to be producing 24/7 just to meet annual demand so it would have no ability to scale up for a sale or the spring sales surge. 

Keith Tanner said:

Oh, I appreciate it. But we are totally strapped for people here and no, we can't just hire more. There is no broom pusher. Mixing/pouring/cleanup/finishing and dedicating someone to doing that for a couple of days - that's manufacturing. The 3D printer farm is about as far as we want to go in that direction. I know, there's potential money to be made by being a manufacturer but let's just take that as a constraint.

It's been enough of a challenge distracting our R&D guy long enough to put in a quote request with Protolabs.

Sounds like you need interns

Interns aren't free! They think they are, but good lord are they not.

In my experience, $50k would be towards the top of the spectrum for a 1k/year injection molding tool. I'd assume this is a single cavity mold. Depending on complexity, number of slides, plastic material, etc it could be as low as  $ 20-25k for the mold.

I've used Protolabs and also Ash Industries. Both have their place and can make part cost effectively. 
 

The key difference are accuracy, process control, and adjustments to fine tune the dimensions. You'll need to assess what your needs are and what materials you want to use. 

Protolabs is fast and cost effective for quick turn, but definitely some compromises compared to a production type of molder. My experience is that Protolabs typically won't make adjustments to tooling to get into tolerance. 

Ash may not be as fast as Protolabs, but uses steel tooling and will fine tune and tweak tooling (it might cost some money) to get into tolerance rather than make a whole new tool. 

Ash Industries - Supermold