Set track points

[MOH]

Apologies as I know this has been done to death but maybe some kind soul/s might condescend to help me out, what are the basics of the plastic shim remedy for the vee gap in set track points?

 

If I am running short wheel-based wagons say or some steam tenders there is what appears to be a tendency for wheels to drop into the gap in that area causing derailments, I recall people fixing that with the shim method but I need the size/type/thickness of plastic and exactly where to place it, also advice on the type of adhesive to use please if possible.

[DCB]

The shim works if you have consistent flange profiles.  The old Hornby Dublo 3 rail points relied on the flange running along the bottom of the V when passing the gap and they ran very well, as long as you used Hornby Dublo wheels.  I shimmed some points myself but had to remove them as when small flange wheels ran nicely and didn't drop in the large flanged ones climbed over. 

Set track points are a common source of derailments, doesn't stop me using them where space is critical but I like to trim them to streamline spacing of 52mm and live frog them. Then again my latest layout in OO has 12" radius curves.

[ITG]

Is this more due to varying wheel profiles, rather than the set track points themselves or the wheel base, as mentioned by op?
i do have a few settrack points and don’t suffer derailments although I did either rewheel or dispose of some older stock I had acquired before I realised the problem.

[MOH]

Thanks,

 

Initially I want to try the shim method so if anyone can let me know just how and where to place the shim (and its size/thickness) that would be great.

[steve22]

Not a shim remedy (and therefore easily discarded), but something I read a great many years ago, possibly in the MRC hints and tips page, was to fill the gap with papier-mâché.  When almost 'set', very gently push through your loco, wagon or whatever with the deepest flange.  This would create a groove below which nothing could fall.  In the intervening half century or so I don't recall ever reading of this idea again but, as Norman Clegg might say, I offer it up for what it's worth.

Steve.

(I suppose if it doesn't work you just dig it out!)

 

[JDW]

Apologies if I'm barking up the wrong tree, but many years ago when I used Hornby small radius points I found that certain locos would derail (but not on similar Peco ones). The solution I used was to put a shim of thin plastic on the check rail on the curved rail opposite the V as the flange gap was too wide, letting the wheel ride up onto the frog as it crossed the V and causing a derailment. A thin shim on the face of the check rail kept the wheel/flange closer to the running rail and pulled it over just far enough that the opposite wheel would take the right route through the gap and not hit the end of the V or try and ride up and over it. 

[Booking Hall]

I've done this mod on a number of Setrack points, to try and reduce the tendency for wagon wheelsets to drop into the large gap. I use some 30 or 40thou microstrip, welded to the point plastic with PlasticMagic solvent, then, when fully hard, I run a parallel file which happens to be 55thou thick up the gap following the track direction as closely as possible to create the slight angle at the crossing V. Then I just take off the sharp edge at the top of the shim. Although the reduction in crossing gap is small, it does make a useful difference.