Garden Railway Forum

This week's project has been getting this little rake of 3D printed and laser cut Ffestiniog coaches ready to run. They are based on the Thingiverse design, but with more laser cut elements, including sides and ends. Couplings are magnetic choppers, based upon the supplied couplers, but with a smaller buffer and embedded 6mm magnet. They work very well, holding the train together, but being easy to split when required.

You will notice the headless train in the videos. This is my dynamic control van for MSS and other uncontrolled steam locos, but it has enough power by itself to drag some stock around. Perhaps it's a runaway train...

Interesting, thanks for sharing.
Those couplings look very neat.

BTW, there is a better way of posting Youtube video's to the forum. Take a look at the "How to" section and specifically, https://gardenrails.org/forum/viewtopic.php?f=62&t=9208

Thanks for the heads up on the video.

I had not used the Share link. Corrected now.

Wow, some really sharp models! I've been doing a lot of 3d printing lately but I'm starting to think I really could use a laser cutter. I usually end up batching up the flat stuff and running out to the bandsaw to cut it out.

It's certainly quicker using the laser cutter, but you do need suitable space to run it. They produce a lot of smoke and burnt particles, so good ventilation is a must. They need to be watched while cutting, in case they set fire to the work piece and finding the right materials at the right price is a never ending challenge.

All that being said, I would estimate 30% of my model making is now done on the laser cutter, with the resin and fdm printers seeing about an equal share. I've just started to play with cutting out chassis from aluminium using a mini CNC cutter, and the first attempts are promising.

What mini CNC are you using?

Phil.P

drewzero1 wrote: ↑Tue May 30, 2023 5:10 am Wow, some really sharp models! I've been doing a lot of 3d printing lately but I'm starting to think I really could use a laser cutter. I usually end up batching up the flat stuff and running out to the bandsaw to cut it out.

https://all3dp.com/2/convert-3d-printer ... raver-mod/

Rik

Tidy work, love the couplings.

I love the headless train.. and the Alien in the first photo is also scary..
Seriously I think you have done a brilliant job with your builds, although for me a laser cutter would be out of the question, far too much technical stuff like rewiring and stuff.

I too like the couplers, I have some magnets somewhere in our house or shed but trying to find them is just a nightmare

Thank you.
The laser cutter is a standalone unit, so no rewiring or anything. Main issues are safety - not setting anything on fire, fume extraction and exposure to the laser beam itself.

I use a floor tile underneath the laser to give a heat proof, non reflective base, wear glasses that reduce the danger of exposure to the beam, and run the thing in my summer house, with fans, extraction and the doors open. I only cut wood and card, as plastics can be dangerous if you get the wrong stuff.

I get the magnets for my couplings from an old science construction toy the kids used to play with. Each component contains 2 magnets, so perfect for a pair of couplings. You can also buy about 50 magnets from Amazon for less than £10 delivered, so they are a very cheap method of creating robust, good looking couplings.

What size are your magnets - thickness and diam? I have some small round magnets so I might give this a try, but I'm wondering whether what I have are too small and therefore not strong enough. Presumably you just glue them in?

Mine are 6mm x 2mm. If you have smaller ones, they could be mounted side by side, one north, one south, so that the coupler becomes omnidirectional.

And yes, an interference fit and dab of super glue.

Thanks. I'll have to have a play, I think. The ones I have are 9x3 and 3x2. I suspect that the bigger ones are too fierce and I'm sure the smaller ones are too weak!

My files are here: https://www.thingiverse.com/thing:6090339

Cheers. That should save an hour or two of drawing.

philipy wrote: ↑Thu Jun 22, 2023 1:44 pm Cheers. That should save an hour or two of drawing.

More like 5-6 hrs for me Philip ..

Just printing some off now to see how they go ..

If there's enough interest, I'll redraw them to take a pair of 3mm magnets, so that they become bidirectional.

Strength wise, I can pick up the 4 coach train and dangle it from the couplings. That's about 1Kg, so more holding force than I'll ever need on my little railway.

I like the concept of magnetic couplings. - I did try something similar for power connections between vehicles.

For actual couplings, I have not found a way to uncouple automatically, without an enormous electromagnet. - I may be looking at the problem from the wrong angle (as it were)?

Phil.P

To release the magnets, a bending force works better than directly pulling them apart. Perhaps that's a better starting point for an uncoupler - a device to rotate the coupler 45 degrees or so?