3D Printed Mechanical Locking?

[St. Simon]

Hi,

 

I’ve been thinking about getting a small Lever Frame and Mechanical Locking for my new layout.

 

However as Modratec have stopped providing them and, whilst I’m a trained machinist, I haven’t the equipment, I was wandering about 3D printing a frame.

 

The question is, how practical would it be? Would resin have the mechanical strength?

 

Simon

[KeithHC]

I will stick my head over the parapet. I think PLA filament would be better than resin. I presume the locking would not be too scale. It is something I would like to do if I could get my head around locking design and operation.

 

Keith

[Crosland]

How about a combination of 3D printed and more easily fettled metal parts?

[Jeremy Cumberland]

Have you seen the Blockpost/S4 Society offering: https://blockpostsoftware.co.uk/L_frame.html

 

Personally I would have thought 3D printing wouldn't be strong enough for any of the moving parts, whatever material you were using. If you wanted to do your own design, then etching looks to me to be the way to go.

[Nick C]

Have a look at the 'Bexhill West' Youtube Channel - James @makeitminiature is building one using a mixture of techniques.

 

@Echini on here did 3D print one though - although the thread is somewhat stale and the photos all gone:

 

 

I've been looking at various things too as I'd like a properly interlocked frame for mine - I've got a Modratec frame that I'm hoping I'll be able to re-lock for a different layout. It's a shame nothing seems to have happened with his idea of making a "Modratec club" to keep the designs alive - you can't even get the very useful 'sigscribe' software any more.

[Bittern]

For a small frame with simple interlocking you might have more luck using FDM printing or laser-cut plastic to implement a system like the one AMBIS make (made?) based on slotted plates. (Similar designs were used by Hornby Dublo and, briefly, the NER.) A home-made clone was written up in Railway Modeller in the 1990s, along with an explanation of how to implement some locks, but I only have paper back-issues so it will take a while to find.

 

If you're interested I can sketch up the basic elements, and/or try to find the article. The big limitation is that it can't do some types of conditional locking without losing the simplicity and robustness that are its main advantages, if it is possible at all.

[Mike Harvey]

19 hours ago, Bittern said:

For a small frame with simple interlocking you might have more luck using FDM printing or laser-cut plastic to implement a system like the one AMBIS make (made?) based on slotted plates. (Similar designs were used by Hornby Dublo and, briefly, the NER.) A home-made clone was written up in Railway Modeller in the 1990s, along with an explanation of how to implement some locks, but I only have paper back-issues so it will take a while to find.

 

If you're interested I can sketch up the basic elements, and/or try to find the article. The big limitation is that it can't do some types of conditional locking without losing the simplicity and robustness that are its main advantages, if it is possible at all.

There is a detailed article by Mike Cosgrove in the July 1996 Railway Modeller.

[Bittern]

2 hours ago, Mike Harvey said:

There is a detailed article by Mike Cosgrove in the July 1996 Railway Modeller.

That's the one I was thinking of — I thought it was a bit  later, no wonder I couldn't find it.

[e30ftw]

I don’t see why you could not use thick plastic, it’s only going to be operated by your fingers/hand, you shouldn’t be swinging off the lever trying to break the interlocking, it should just stop accidental movements.