3D printing liability

We do 3D printing at A&A, and we have been really careful in the terms and conditions on this. We sell a service that is renting the use of the 3D printing kit, with staff to run it, and selling the materials. We don't sell the finished item, and we make it clear that the customer is the party that manufactured the item using our services. We even require the customer to indemnify us against any claims.

This may seem somewhat over the top, and I would agree, but the laws on manufacturing are scary!

We, if we were manufacturers, could be liable for all sorts of shit, not least of which revolves around copyright and patent and registered design issues, but also things like CE marking, and toy safety and food product safety. It is mental. No way we want to be involved in any of that. We are not "manufacturers" if we can help it!

We have done a few 3D jobs, and mostly fun things, and even some robot heads for a university project. Nothing that gets close to any liability. Long may it be so... A&A are pretty good at this if you want any 3D printing done.

But today I had an unusual job request, and it was one that made me think of all the possible liability issues, for me and A&A. What was unusual is it was a request from my grandson, age 8, and so not someone A&A could, or would, engage in any contract. This makes it personal!

This was the design brief...

To clarify - that is drawn on some cardboard and cut out. It is a "knife" or "sword" that he wants. Something related to a game or TV show. I know he is in to Assassin's Creed, but this may be related to some show called" Forged in Fire".

So I made a blade and a handle...

The blade is printed in 20% Carbon Fibre PLA, and actually very strong. The handle in wood filled PLA. The end result is quite nice. But to be clear, this is a plastic toy knife!

The problem is that the result is pretty solid and strong. I really do not know if it could cause injury or not. It is a "toy" for him. I "made" it as a toy, or did I let him instruct me such that he "made" it? If, legally, I was responsible in some way, it would be easy to have have him drive the computer and make him the actual manufacturer. Let's assume we did that, for now.

It raises a lot of questions - can a 3D printed "knife" be an effective offensive weapon? Who made it? What next?

Well, he knows to "be careful" with it. I think I have designed it to be "pretty blunt" at the tip to try and ensure it is not actually dangerous. As I say, it is a plastic toy knife.

But what if someone made something that really was dangerous? What then? This is not a simple issue.


  1. I think the Merkin's would call this a shiv

  2. Surely, in this case, as he is underage (as in too young to understand all the implications) he can't be held responsible as he can't hold a legal contract with you to produce the item and thus by allowing him to produce the item, or even drive the machine, himself, you could still be accountable?

    IANAL, just possibly Devil's advocate.

  3. This might be the start of some case law...


  4. Please don't give your eight year old grandson a fucking weapon.

    1. That's not a knife...


    2. Quite, and if his gran and his mum are happy, who am I to argue...

  5. I wondered how long it would be before you were asked to print a liberator

  6. I'd just stay away from anything that looked like a weapon... Easier legally, and then you don't have to worry about the moral responsibility if something does happen.

  7. Don't be ridiculous, it's not bladed anymore than a play pirates set is, therefore CJA isn't relevant.

    As for the PCA, ANYTHING used offensively (as you've outlined RE: brick/wine bottle) is classed as an offensive weapon, but only once it's used in that manner.

    There is no issue with this particular item.


Comments are moderated purely to filter out obvious spam, but it means they may not show immediately.


I am, once again, getting more spam. Someone must have put my email on some mailing list. This is a pain in the arse, takes up my time, and ...