Constraints not working properly

Hi guys I’ve been doing the tutorials at http://gryllus.net/Blender/3D.html

11A shows how to make a part of a steam engine and animate it. I’m having a problem with the constraints letting the components shift like they shouldnt.

I double checked and I’m doing nothing wrong but I cant get it to work. Even the completed .blend file the tutorial provides does the same thing. How can I get these constraints working.

You will notice the middle linkage moves

steam-engine-1.zip (106 KB)

This seems to work better with an empty to ensure travel distance of the piston rod is better

Attachments

steam-engine-1 2.blend (646 KB)

Thanks a lot. I figured it wouldnt be too complex. Its not like its a complex mechanism.

The tutorial does suggest changing the sizes might solve it but I tried that for hours with no luck. Clearly since the writer never solved it himself he had the same problem.

Thank you for your quick reply.

It’s usually best to have all objects with a scale of 1 (yours aren’t). You should fix this while you can before using any constraints otherwise you end up trying to fix one problem on top of another.

Ok thanks a lot. I’m going to leave it for this tutorial unless it tells me different but I will bear it in mind in scenes I make myself