Desktop Manufacturing Part 3: 3D-Printed Tooling for Injection Molding

[Ace-Garageguy]

Some time back, in a "kit review" thread that had a bad habit of running off the rails into "the kit manufacturers should do this and do that" (but with little grounding in the economic and technical realities of the model-kit-manufacturing industry as it exists), I posted several links to videos that illustrate pretty well what some of today's low-volume manufacturing options are, how they work, and a little about what they can do in the not-too-distant future.

I don't think the majority here saw most of this info, so I'm going to post a 3-part series of links to what can be done TODAY in LOW-VOLUME DESKTOP MANUFACTURING. The technologies are game changers, can conceivably keep the scale-model hobby alive and well for decades to come, and take a capital-intensive industrial business model and put it within reach of a middle-class guy working on his own.

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PART 3: One of the reasons so often cited for the high cost of producing injection-molded plastic model kits is the need to machine the dies necessary from solid blocks of metal. This cost can't readily be justified with runs of product that have limited appeal, and won't sell enough units to make the investment back and go on to generate a profit. True enough, but with the advent of "soft tooling" that can be printed directly, or made from high-performance composite materials and developed from high-quality 3D printed masters (as shown in the first video of this series), or even from masters produced using traditional methods, short-run injection-molded products become quite possible, while maintaining the ability to make a business-sustaining profit margin.

Combine the ideas presented in these three videos, and you'll see what's entirely possible if a "yeah, we can do that" attitude replaces the "can't be done" that's so prevalent everywhere.

 

 

 

Edited January 11, 2019 by Ace-Garageguy

[Dave Van]

More interesting.......

I knew of epoxy molds and aluminum short use molds. These have been used for a long time in the model rail hobby.

But as a retired bank analyst......I'd still like to see cost analysis to see if this could be the start of the next 'Modelhaus' cottage industry.  

Thanks

[Ace-Garageguy]

17 minutes ago, Dave Van said:

...But as a retired bank analyst......I'd still like to see cost analysis to see if this could be the start of the next 'Modelhaus' cottage industry....

An in-depth cost analysis would likely cost more to produce than buying all the equipment, modifying some of it, and producing a run of parts.

And it would take somebody with my particular combination of skills and knowledge base to produce anything that was accurate and realistic.

I'm available as a consultant...or will be as soon as I finish the two 1:1 client car projects I'm committed to.   

PS: I will say this. I've researched these processes and materials sufficiently (and have sufficient technical background to understand them completely), and my gut (which is usually right when it comes to seeing what's possible) tells me that a combination of the three technologies presented in the videos could be made to work cost-effectively in either an aftermarket-parts or short-run-kit setting, if the principals had the right skill-sets and knowledge base.

 

Edited December 10, 2018 by Ace-Garageguy

[Spex84]

This is all fascinating stuff, thanks for adding these video links to standalone posts. The 3D printer you mentioned in part 1 is the first printer to really make me sit up and say "wow, this could be the one I actually buy!". Acceptable detail at an acceptable price, perfect!

As for 3D printing molds for a desktop injection molding machine, when I look at the whole process, the bottleneck is the slight texture imparted to the parts by the 3D printed tooling. If they could be printed perfectly smooth, then it wouldn't be an issue.  Metal molds can be polished--witness the complaints that arose when Moebius kit bodies had a slightly pebbly texture, but they allegedly went back and smoothed things out some more (I wouldn't know, I don't have firsthand experience of that issue).  Fix that, and everything becomes possible, including 3D scanning and rapidly producing shoddy ripoffs of production kits, haha.

Exciting to see what the possibilities could be for scale model production in the very near future!

 

 

Edited December 10, 2018 by Spex84

[Dave Van]

If I had enough interest in this I'd do the analysis myself. I headed up the due diligence team on some of the worlds largest bank mergers. 

But I invested a lot in two laser cutting machines to use in the model rail hobby. Thankfully I looked on it as my retirement 'hobby' expenditure. I have never made any money per the books....but lots of fun. Desk top injection looks like it may be the same. 

This was a laser project that I did sell copies of....but at around cost. thx

 

[Ace-Garageguy]

9 minutes ago, Spex84 said:

This is all fascinating stuff...Exciting to see what the possibilities could be for scale model production in the very near future!

Glad you got the point. 

Something I should elaborate on...it is also possible to take the models shown in the first video AFTER they've been primered and are slick, and cast two-part injection molds from from a high-performance catalyzed casting resin...much like silicone molds are made of masters for resin cast replicas.

Hand-made masters can also be used for the basis of injection molding tools.

If the parting lines are handled carefully, current kit-quality is achievable.

[Ace-Garageguy]

6 minutes ago, Dave Van said:

If I had enough interest in this I'd do the analysis myself. I headed up the due diligence team on some of the worlds largest bank mergers. 

But I invested a lot in two laser cutting machines to use in the model rail hobby. Thankfully I looked on it as my retirement 'hobby' expenditure. I have never made any money per the books....but lots of fun. Desk top injection looks like it may be the same. 

This was a laser project that I did sell copies of....but at around cost. thx

Pretty cool !  

Honestly, I've done enough of the costing (back-of-napkin) to have a pretty good idea of what it would take to get going with this, but much depends on the desired direction (full kits or aftermarket only). I know people who have the one necessary skill I have but am not sufficiently proficient in currently (developing 3D models from a wide variety of data), and again, the whole thing is doable.

Starting with aftermarket "parts" would make the most sense, bootstrapping the business to produce limited run kits as income grows.

But like any other manufacturing enterprise, success or failure depends on the final market acceptance of any given product, and many folks who say "yeah, I'd buy that at such-and-such a price" don't actually cough up when the thing becomes available.

I even have someone willing to back me in a venture, but I don't want to retire from what I'm doing now just to go into another full time business with model cars.

I have too many real car projects I want to do in the limited time I have remaining.

But the potential is there for anyone who wants to pick up the ball and run with it.   

[Dave Van]

10 minutes ago, Ace-Garageguy said:

 

I have too many real car projects I want to do in the limited time I have remaining.

But the potential is there for anyone who wants to pick up the ball and run with it.   

About the same here. I am realizing I have more ideas than time!  I'm going to be happy with my laser machines. I had to self teach 100% of that and while I will watch desk top injection.....I will only watch. Thx