okay the key - I find - to mgetting good prints that don't need supports, is to build up at an angle.

so instead oif the end coupling part being a vertical lift from the base, you would have an angle to the edge of the square part.
Obviously this is dependant on whether or not the wagon blocks the chance of an angled support.

And it also depends how well the cad program you use makes this kind of thing.
I just use openscad. and in that the 'hull' command is king.
It automatically wraps a 'skin' around two parts, creating a seamless transition between the two parts - no matter what shapes they are.

Without seeing how they connect to the carriage I don't really know how I'd do that particular model.

The other thing to bear in mind is that you can also print the model at an angle.

Here's an example for an insect catcher I made.
catcher1.JPG

catcher2.JPG


basically it's a pyramid on a stick with a sliding door. You swivel so the door is open, put it over the insect and swuivel so the door slides closed and remove insect to the outside.

The tricky part was the channel the door slid in.
In the end I split the body into 2 parts. That way I could print the main part on an angle so that the channel printed clean and wthout needing any suport.
I then had a cylinder with square foot that pushed through the hole and formed the top cyolinder that the flexible tube pushed onto to link the catcher with it's stick. (literally sticks I curt from a piece of pine shelf).

By printing at an angle you can make shapes that would otherwise not be possible without supports. And removing supports from a 2mm channel is not something I relished.

complete.jpg

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