Colin Parks wrote:Thanks for your replies Andrew, Julian and Howard.
This also means that I cannot use Howard's, method of having loose-heeled switches.
Just before I consult my solicitor to pursue a case of liable, can I just correct a couple of misrepresentations please?
Firstly, I don't use "loose heel switches" - except where the prototype demands!! For my bullhead track, my switches are a replica of the prototype - there is a fishplated joint to the closure rails, and the switches are anchored to the stock rails by mean of Switch Anchors.
(This happens to be an A switch trap point - hence the rail is not fully cut through on the far side where the fishplate is not yet fitted)
... which is a normal B switch.
I hope the evidence is there to prove that these are FLEXIBLE switches and NOT loose heel switches and, should anyone allege otherwise I there will be writ!!!
Further, I hereby give notice that anyone claiming that they notice a kink in my switch / closure rail joints will be asked to provide photographic evidence. My Silk will be briefed should these not be forthcoming.
Perhaps linked to this, it seems that persons hereabouts are contemplating using fishplates to locate the heel-end of their switches, and whilst they are perfectly free to do so, when the whole thing turns out to be a disaster, should those individuals allege that they did so "because Howard Bolton does it", I will again be suing for damages.
If I could also add a piece of advice to any such individuals - use a track rivet as a pivot if you wish - but it will not last 10 minutes. I suspect that it has not be tried more than a half a million times in the past 50 years...
Meanwhile, just on your FB switches Colin, I think you are likely to run into a very serious problem due to the stiffness of the rail. Although you *might* succeed in getting a decent opening at the extreme tip of the switches, because the tips are so much more flexible than the rest of the rail, you will never get a proper flangeway through the minimum gap and derailment is the inevitable result. I think for this reason, in FB even more than in BH, designing in some flexibility is essential. My suggestion would be to not use such heavy bonding strips but to use wire - although the real thing does not use switch anchors, it should be possible to use a straight piece of 0.8mm N/S wire to link the switch to the stock rail at one of the positions where the prototype employs a spacer block - preferably the first one inside of the fishplate. The subterfuge can then be hidden under a plastic representation of the spacer block. Needless to say, I would cut the rail fully at the fishplated joint. It might be that the stiffness of the rail does cause a slight kink in the open switch in FB (but remember that they are longer than the BH equivalents) but that is much preferable to a derailment risk. Just in case anyone should suggest that this make it a loose heel switch, I give notice that my Solicitor is already speaking to my Barrister on the matter.
If I cannot persuade you that would work, then an alternative would be move the bonding strip to beyond the fishplate (though there is no prototype reason for one there) and then at least partly cut through the rail at the fishplate - I use this method where the prototype uses a loose heel switch but where there is insufficient space to engineer a pivot - thus:-
Must go - phone ringing, must be my Brief...
Very Best Wishes,