Inadvertent copyright or patent infringement is still infringement

I decided to make an Ogauge [Lionel ] scale Block
signal with my F2.
.I gathered as many photos of real train signals I could find to use them as a design basis
One of the photos was from a company that made, actually used to make , 1/4" scale signals. Using the photos I made a 3D model in my modelling program.
I posted my progress on a toy train website to which I posted other models of interest to this hobby.
I also attach a copy of the modeling file for use by others as I claim no interest in a copyright.
I was about to attach a copy of the block signal design as well until I realized that I infringed on a copyright.
Because a 3D printer makes it so easy to make stuff you should consider what you make.

I’m pretty sure you’re not infringing on a copyright when you create an artistic interpretation of a real-world object. It doesn’t matter if someone else has done the same thing and yours looks similar, or even if you borrowed ideas from that someone else’s design of the same real-world object. It’s called “Fair Use”. You’re only infringing if you used their original source material without modification and/or if you represent your creation to be the same thing as someone else’s, and then tried to sell the thing. Otherwise, whoever else made the similar thing first might be upset with you for copying their idea, but you’re not doing anything that they can sue you over and win.

you can copy for self usage but circulation is infringing. Perhaps it is legal to give stuff away for free, maybe there is someone who can point to an article which explains this in terms simple folk understand.

All models are copies. So if there really were to be any chance that copyright was being infringed then the whole model industry would grind to a halt. Having said that it is not a good idea to copy other models, as you don’t know what compromises the other modeller has made. You are likely to get a much more accurate model if you base it on original documentation, i.e. either works drawings, photographs or both.

I am fairly certain that Copyright and Patent, at least in the USA, refer to different things. Copyright, if I remember correctly, has to do with written material. Patents (there are different sub-types) have to do with physical objects.
I could be wrong, but that’s the just of those terms in the USA.

Copyright in this context refers to the model file, which is “text”, like source code.

If I understood correctly, the OP didn’t start with someone else’s model. He made his own of the same object, and incorporated similar features found in that other model in to his design. There’s no copyright infringement there.

I think that if he took the other model file in its entirety and modified it, that potentially falls under “fair use”. Provided the changes he made are “significant enough” that his model is clearly not the same model, there should be no copyright infringement there, either.

A generic part as long as it doesn’t have a companies name on it should be safe. You can check and see if there are patents or any copy protection on that through the patent office
Some of the RR companies are sticklers for that sort of thing especially if it has names on them. Some may extend permissions and you can always ask them.

If they designed the real object and you made a 3D model of it then that would be infringing. That’s like making a print from something in a movie.
In most things there’s some company that owns the design, so for example making a vehicle can infringe pretty easily.

Only if the object is one that is ‘artistic’. There is no copyright on practical objects, such as most railway equipment, though there are some grey areas where, for instance loco and rolling stock have been ‘styled’. There can be some problems copying logos and liveries, but in general they are dealt with under legislation that covers branding and trade marks rather than copyright, if only because infringement is easier to prove.

An idea is not copyrightable. You cannot claim a copyright for the idea of a trackside signal. However, you can claim a copyright for your “unique interpretation of the idea” of a trackside signal.
Here I copied and 3D printed someone else’s interpretation of a trackside signal as an Ogauge signal. That’s infringement.

One of the tests of infringement asks did you make your interpretation with a picture of the copyrighted item on the room. NOT ONLY did I have pictures I had a scale signal that I calipered for dimensions.

The point is that as paper printers made infringing photos and documents real easy, a 3D printer makes infringing objects easy too.