Radio Controlled locos, lorries, cranes etc. Electroplating

[Giles]

 

[Giles]

I've completed a prototype of the uncoupling system I had envisaged.  It's 3D printed with an N20 gearmotor driving, and a small microswitch for indexing. It appears to be completely reliable in function, so this is what I will go with when I have the freedom to commence the next layout. The benefit for me is I can retrofit stock and locos easily. 

 

 

 

 

Edited November 16, 2020 by Giles

[Barnaby]

That's very neat and clever Giles.

 

I've been thinking about using magnetic couplings but the uncoupling has always stalled me.   Coupling up is not to difficult to achieve by the swing "Magclics" method which only then require the hand of God to push down on to separate them or just pull them apart. 

Not very attractive or realistic so how to make them auto uncouple? 

 

I beer -matted some ideas, a rod that pushes up to lock the wheels axles when pulling apart, or a degaussing unit that diminishes the magnetic field and allows separation.

Neither will work very well but a combination of those ideas might do it.   So have a rod raise up with a magnet on its end of greater strength than the coupling and grab onto a metal plate fitted under the wagon, then pull the loco away to uncouple the loco to wagon hold.   Sounds plausible but it falls down as it wont allow you to pick a wagon out reliably as wherever the weakest hold is is where it will split.

 

I notice you haven't shown how you make the uncoupling work or I have missed your explanation.   I heard you say you 3D print a part and that there is a gear motor working under the BB but not actually how it performs the uncouple action.

 

Regards

 

 

Thanks

 

[Giles]

Sorry Barnaby - I'll get to that - hours in a day!

[Giles]

So.... here is the Scotch mechanism.

 

A straightforward cam, giving about 7.5mm of lift, indexing at 180 degrees on a microswitch, with an override button.

The motor is any chosen N20 gearmotor of whatever voltage, but you really want about 20rpm out the end of it. This is actually a 12v running off 1.5v.

I shall do another iteration with a second microswitch to detect the UP position for a panel light.

All in all, it is 4 prints in PLA - about 3 1/2 hours worth.

 

Of course the by-product of this is that it could actually operate a number of things - points, signals whatever...

 

 

 

 

 

 

[Giles]

I'd forgotton this.... this is the business end..... a Scotch

 

 

[Barnaby]

I see it's a typically Giles detailed working.  A beautiful engineered mechanism to solve an engineering problem. 

 

Sadly my effort will no doubt be some what cruder. 

Questions -- How critical is the magnetic strength requirement -- do you need to have a magnet on each coupling or just on one end and a non ferrous plate on the other.  Then a like pole magnet under the board would repel the  same pole coupling magnet.  Mnnnnn ideas.

 

Good work Giles your giving me ideas.

 

Best

[Dave John]

A well engineered solution Giles. Like you I can see the potential for operating all sorts of things with it. 

 

Additionally it has the advantage over servos or stall motors of consuming no power at rest. No servo jitter as well. 

 

As a matter of interest I found that converting a cheap sg90 servo to a free running motor/gearbox is very simple. Open it up, remove the servo board , a couple of cuts on the output gear with a scalpel is all that is needed. Could be useful for making a mechanism similar to yours but a tad smaller ? 

[Giles]

52 minutes ago, Barnaby said:

I see it's a typically Giles detailed working.  A beautiful engineered mechanism to solve an engineering problem. 

 

Sadly my effort will no doubt be some what cruder. 

Questions -- How critical is the magnetic strength requirement -- do you need to have a magnet on each coupling or just on one end and a non ferrous plate on the other.  Then a like pole magnet under the board would repel the  same pole coupling magnet.  Mnnnnn ideas.

 

Good work Giles your giving me ideas.

 

Best

 

The magnetic strength does very much affect the performance/attributes,  insofar as a magnet that is too powerful makes for unrealistic coupling, and one not powerful enough won't pull the train - so therefore experimentation was necessary.

These couplings have two magnets per fitting - one facing North and the other facing South - always the same way. This means that you can put the stock on any way round and it will always couple. I think I will use the more powerful 2mm dia magnet couplings for stock that I intend to run in a fixed rake - I've not quite made up my mind!

 

You certainly can go for a single magnet - but then the loco and stock must always face the same way........

 

There's a possibility I could put this stuff up on Shapeways or Thingiverse if people wanted it - although I've never used these companies, do I don't know how it works.  PLA is certainly a good material for the Scotch mechanism,  and it's nice and strong for the couplings, though it lacks resolution, so a different material might be better for them.  The Scotch blade is proportioned for narrow gauge or 4mm standard gauge, but it would be very easy to substitute an 0 gauge standard gauge one.

 

[Giles]

2mm couplings here.... the 1mm type are identical, just with teeny magnets in the same place!

 

 

[Giles]

 

 

[Hal Nail]

On 03/12/2019 at 19:33, Giles said:

 

 

2019-12-03_06-12-45 by giles favell, on Flickr

Giles,

I've got my cab off and drilled out all the rivetted glazing etc but cant for the life of me work out how to release the yellow part of the rear sub frame from the grey chassis, at the very rear. I assume there is a screw under the spare tyre but not sure how to get at it.

 

Can you remember?

 

Thanks! 

Edited November 19, 2020 by Hal Nail

[PhilJ W]

I don't know if this will be of any help but the Cararama trucks had the spare wheel glued over one of the screws. To get to the screw the bond had to be broken .

[Hal Nail]

10 minutes ago, PhilJ W said:

I don't know if this will be of any help but the Cararama trucks had the spare wheel glued over one of the screws. To get to the screw the bond had to be broken .

Thanks, yes turned out to be the case. I don't normally need a second invite to go for brute force but everything else came apart easily so I was dubious. The tyre is still welded to the chassis even now but I've got the back off around it. 

[Giles]

...Absolutely!

[Giles]

 

 

[Giles]

Something else I've been working up...... I should have like it if someone had wanted to produce it - but that doesn't seem likely

 

However , it can be printed at home.....

 

 

 

[34006]

Love both these Giles,especially the walking man! Got to have one of those point machines,got just the place for it.

 

atb

Phil

[otherplanet]

That walking figure is inspired. Oddly, I had been recently contemplating some sort of automata, but nothing that good. 

 

Is the raised hand going to carry a lantern? It looks suitably posed to make a perfect night Watchman.

[Giles]

I confess...... he's the only figure I had in stock!......

[PhilJ W]

I have given a friends 12 year old one of these as a Christmas present:-

 

He's over the moon with it, its great when a present is appreciated. Looking at the video and the actual model it shouldn't be difficult to swap an alternative body on to it.

[Simond]

Pretty, but not a real mini, it’s not front wheel drive

 

Merry Christmas!

Simon

[Giles]

Winding back a bit.......

 

The Peckett I built up recently has one compromise which I couldn't particularly help. The steam dome. It's a very good white-metal casting, which cleans up nicely, and of course should be brass. Now I have made brass domes in the past (some 0 gauge kits are carrying castings from patterns I made long ago) but it is a faff,  and I wanted to use the actual kit on this loco, otherwise I would end up throwing too much of it away, and actually it's a very decent kit as they go..... I therefore painted it, taking trouble to read the paint instructions for a change, and it didn't look too bad...

 

 

 

My Christmas present from Di has been a simple electroplating kit, comprising of a decent power supply, chemicals for copper, silver and gold plating - in small quantities,  leads and copper and graphite anode. This was all a complete surprise may I say!

 

I have another Peckett kit, for which I have already cut frames and rods,  and I thought that the dome might make a suitable experiment for plating!p

 

I cleaned it up and polished it, and set up the kit, and in three minutes had copper plated the dome....

 

 

 

This was it after two minutes of buffing with a kitchen towel (no polish)

 

I then set things up for gold plating (24 carat, no less!) and, zapped in for about five minutes

 

 

 

And hey presto, a 'brass' dome....... and a successful experiment!   

[Giles]

And...... back to the Walking Man for the last time.

 

Grass is probably the best medium for disguise- but make your own mind up..... you need a 4-5mm slot. The only way I've found where you can actually go over the slot is with feathers, which allow the feet to pass through, and will settle back afterwards, like an extremely gentle brush-strip.

 

The slot can be straight or curved, as the Engine and Man is reasonably forgiving.

 

 

[Simond]

That is great!
 

I bet he does a really brilliant Michael Jackson Moonwalk in reverse...