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Re: RWLR - Robin Wood Light Railway

Posted: Sat Aug 11, 2018 9:03 am
by ge_rik
tom_tom_go wrote: Fri Aug 10, 2018 4:39 pm PVA is what I used indoors with OO scale but I wouldn't use it outside!
Glad you are learning from my mistakes.
I tried external PVA in my early experiments with ballast - it lasted about two years. So far, SBR seems to be holding out far better.

All thanks to Peter B for alerting us all to this marvellous stuff.

Rik

Re:

Posted: Sun Aug 12, 2018 4:16 pm
by philipy
Tom,
Sorry for raising the dead, but back in 2016 you inserted this little throw away line in one of your magnetic un-coupling posts:
tom_tom_go wrote: Mon May 30, 2016 5:18 pm With the addition of ball bearings attached to the modified choppers
Ummm... just how do you attach the ball bearing? In my experience they are just about un-drillable and I wouldn't have though glue would be enough to attach a ball to the end of a wire for more than a few seconds?

Re: RWLR - Robin Wood Light Railway

Posted: Sun Aug 12, 2018 6:04 pm
by tom_tom_go
Hi Phil,

I don't use ball bearings anymore as I have found using metal wire or cut down paper clips is sufficient if using neodymium magnets attached to the track (use these if you are going to play about with this type of uncoupling, normal magnets are not strong enough). I now glue plastic beads to the ends of the wire to mimic a counter weight.

However, if you want to use bearings then clamp one in a vice and file one side so it creates a flat surface. Apply solder to the flat side of the bearing then solder your piece of wire to it.

Re: RWLR - Robin Wood Light Railway

Posted: Sun Aug 12, 2018 6:08 pm
by philipy
Cheers Tom.
I notice that you use 75mm long magnets, do they really need to be that long, I'd have thought 50 or 60mm would be long enough?

Re: RWLR - Robin Wood Light Railway

Posted: Sun Aug 12, 2018 6:18 pm
by tom_tom_go
The length of the magnet gives you some margin to stop the loco in the right spot. The first magnets I used were 25mm long and it was a right pain in the back end to uncouple successfully each time without going back and forth.

I guess if you are going to be using electric mice then you have the control so a shorter magnet may work but if using a live steamer (particularly one without an inertia device) then it will become frustrating.

What are your intentions?

Re: RWLR - Robin Wood Light Railway

Posted: Sun Aug 12, 2018 6:49 pm
by philipy
Not really sure where I'm going to end up with this. I'm experimenting with a version of Rik's coupling and throwing around thoughts of adding your magnetics into the mix! If it looks promising I'll try putting loops on a loco and full hook and loop on the ends of a rake of coaches, and magnets on the platform road of Lower Bench, so that I can run round without a big hand from the sky. However it all depends on how reliable I can get it all, because if its not 100% there isn't much point in doing anything.

Re: RWLR - Robin Wood Light Railway

Posted: Sun Aug 12, 2018 6:57 pm
by tom_tom_go
The modified choppers I use are 99.99% reliable :thumbup:

Re: Re:

Posted: Mon Aug 13, 2018 11:59 am
by GTB
philipy wrote: Sun Aug 12, 2018 4:16 pm Ummm... just how do you attach the ball bearing? In my experience they are just about un-drillable and I wouldn't have though glue would be enough to attach a ball to the end of a wire for more than a few seconds?
Ball bearings can be annealed by heating them to red heat and cooling them slowly. They can then be drilled easily enough. Holding them for drilling then becomes the trick.........

For magnetically operating the type of coupler Rik has designed, it would be easier to make the hook out of piano wire and if you need more magnetic mass for it to operate reliably, solder a slice of steel nail to the hook. From memory this is much the same way that Alex Jackson couplings are made to operate magnetically in the smaller scales.

Regards,
Graeme

Re: Re:

Posted: Mon Aug 13, 2018 1:53 pm
by philipy
GTB wrote: Mon Aug 13, 2018 11:59 am From memory this is much the same way that Alex Jackson couplings are made to operate magnetically in the smaller scales.
Thanks Graeme.
For Alex Jackson droppers in P4, I used to fold over the end of a piece of paperclip to make a small hook and then solder that to the 11thou guitar string hook. Worked perfectly. I'm hoping to do something similar with this, but using a couple of iron/steel chain links as droppers. A quick lash up seems to work but I'm waiting for the postman to deliver proper magnets and P/B wire so that I can set it up properly.

Re: RWLR - Robin Wood Light Railway

Posted: Mon Aug 13, 2018 6:51 pm
by ge_rik
Be interested in any progress you make with magnetic uncoupling, Philip. I did consider it, but wanted some way of delaying the uncouple - achievable with AJs but can't figure a way of doing it with hook and loops.

Rik
PS Sorry to hijack your thread, Tom

Re: RWLR - Robin Wood Light Railway

Posted: Mon Aug 13, 2018 6:56 pm
by tom_tom_go
I likes an automatic uncoupler so I would be interested in this as well.

Re: RWLR - Robin Wood Light Railway

Posted: Fri Aug 17, 2018 1:48 pm
by tom_tom_go
Got back today and the SBR is still white so I am going to start again:

20180817_134422-02.jpeg
20180817_134422-02.jpeg (350.58 KiB) Viewed 3629 times

Also, when I touch the ballast I can feel it give way underneath so it has not set hard.

Re: RWLR - Robin Wood Light Railway

Posted: Fri Aug 17, 2018 5:12 pm
by ge_rik
tom_tom_go wrote: Fri Aug 17, 2018 1:48 pm Got back today and the SBR is still white so I am going to start again:
20180817_134422-02.jpeg
Also, when I touch the ballast I can feel it give way underneath so it has not set hard.
That does seem strange. I've not that happen. It can sometimes take a couple or three days to harden off fully, but never had it take longer. Mind you, I usually use concrete to bring the 'ground' up to sleeper or rail height, and then have thin layers of dressing on top fixed down with SBR. Not tried having a deep layer of ballast fixed with SBR. I use a potting grit and cement mix for ballasting track in non station areas.

I think Peter fixes his ballast in both station and non station areas with SBR, so maybe my suggestion of watering it in afterwards is a problem for deeper ballast??

Rik

Re: RWLR - Robin Wood Light Railway

Posted: Fri Aug 17, 2018 5:40 pm
by philipy
Something does seem a bit odd, I was quite expecting Tom to say it was fine when he got back.

I did an entire station just at the end of the hot weather. It had a day or so before the rain came down and even though I covered it before the rain started it was so heavy and coming sideways that it got under the polythene and next time I looked everything had gone white! However I gently prodded and all seemed firm. Left it uncovered for a few hours of no rain and it dried out and the white disappeared. Covered it up but the next rain got under again, and again it went white but only on the sleepers and rails. This happened a 2 or three times and each time it was a bit better but yesterday morning it was all fine and no more white.
So, I think the white is a symptom of a thick layer, because where it went white on the rail head I could actually peel it off in a long thin strip, and the same on top of the Peco buffer stop and some of the sleepers.

Re: RWLR - Robin Wood Light Railway

Posted: Fri Aug 17, 2018 5:58 pm
by Peter Butler
Tom, while you were away you had the opportunity to keep it covered, which I hope you did, this would have given sufficient time for the SBR to dry had it not been diluted with water. The white will eventually disappear in time and when the soft feel of the subsurface sets it would be good to give another application of NEAT SBR and COVER it again.

Re: RWLR - Robin Wood Light Railway

Posted: Sat Aug 18, 2018 8:51 am
by tom_tom_go
My base is gravel boards covered with roofing felt then 10mm pea shingle. Finally, a layer of smaller fish gravel is poured on top.

I think most of you are using a solid base such as concrete or wood with a thin layer of ballast on top so this may be why SBR is working out for you.

Peter, this test section was covered when I went away as advised.

I might try a different area this time using no water to prep the area and covering it up after applying SBR (to note though the first time I tried this on the siding area I didn't use any water).

Re: RWLR - Robin Wood Light Railway

Posted: Sat Aug 18, 2018 10:36 am
by philipy
I have roofing felt on timber with the track screwed down to that and then ballast up to sleeper top.

Re: RWLR - Robin Wood Light Railway

Posted: Sat Aug 18, 2018 11:55 am
by Peter Butler
Gravel boards with roofing felt is used throughout my entire railway and is well suited as a base for the fine grain stone I use as ballast as well as crushed oyster shell which I use as alongside as ground cover. I also use fine (N scale) 'sand' in the harbour scene. All of these materials are stuck down with SBR and remain solid once allowed sufficient time to set.
Picture shows ballast and ground cover as described......
IMG_4429.JPG
IMG_4429.JPG (197.64 KiB) Viewed 4129 times

As you can see there is no sheen on the surface.

Re: RWLR - Robin Wood Light Railway

Posted: Sat Aug 18, 2018 12:15 pm
by tom_tom_go
What brand of SBR is everyone using please just as a comparison.

Re: RWLR - Robin Wood Light Railway

Posted: Sat Aug 18, 2018 12:35 pm
by Peter Butler
Tom, I use Everbuild 503 SBR from ebay, currently available at £14.98 freepost.