Roller Train Tilt Carriage and Some Gear Thoughts!

Hey there, wonderful people!

I guess this is my end-of-month rambling post, but let us start by talking roller trains.  As you've probably already noticed in the photo, we now have a side-tilting carriage, and as usual it's print-in-place and requires no supports.  The wheels and connectors are exactly as in the original carriage, so this one can just join onto the end of any existing train :)

Talking about wheels, though, I'm currently revising how all that works!  There will be a Version 2 of all these train models that will:

* Have less friction in the wheels and turn more readily on less-grippy surfaces

* Fully enclose the bottom of the axle to hold the wheels more securely (but without adding friction)

* Possibly have a thicker axle to reduce twist-derived friction, depending on whether test prints show an overall improvement!

* Possibly have a different connector style that doesn't involve small parts, but that one is tricky.  If the connector changes, though, there will be adaptors to connect both styles together :)

The tilting part uses a nice big hinge-style mechanism anchored to the end slabs, so it works right off the bed, and has the same tolerances that I use with everything (0.5mm)!  

Printing Tips

This thing is designed for straightforward printing - no supports required and no crazy angles.  However, as usual with articulated models you'll want to make sure your bottom layer is nice and neat, and that there aren't any print issues like stringing or overextrusion that might bind moving parts together!

The carriage prints on its side like so:

File Locations

You'll find this one on Dropbox under 788 Roller Train Tilt Carriage

The existing roller train files are nearby, under 789 Roller Train

(Dropbox link post: https://www.patreon.com/posts/dropbox-and-are-31697592 )

Other Thoughts!

There are other roller train parts under way at the moment, but what else have I been exploring in the meantime?  Well, non-circular gears have been a particular thing over the last month, though it's all very much a work in progress, and are still exploratory forms that aren't quite as functional as they need to be to be developed into something more final:

It's interesting to realise sometimes that you've made a fundamental error in a design.  Check out that one at the front -it has two levels of gearing connected together in a rigid way, but it just didn't work.  Eventually it dawned on me that (amongst other errors) I'd overlooked the fact that non-circular gears don't necessarily turn at a constant rate relative to each other.  

Two gears meshed together will move at the same speed at their point of intersection, which means the one that effectively has a shorter radius is moving slower than the one that has a longer one.  The upshot of that is that by binding it to a circular gear that needs a constant rotational speed I'm creating something that can't possibly work :D  There were some other problems, too, but that one was a show-stopper!  Anyway, expect to see some non-circular gears incorporated somewhere, since they're just so cool :)

(and some more train bits, because they're fun)

xoxo

Sven.