A cure for insulfrog points?

Any questions about designing a model railway layout or problems with track work.
kebang
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Re: A cure for insulfrog points?

Post by kebang »

Emettman - Will the blade against the relevant stock rail not provide "switched" power, without going to the disruption of providing a separate switching power supply? I'm thinking of points already ballasted & in situ. (As you rightly surmised the dremel cuts are also intended to avoid lifting the points & fitting them with insulated rail joiners)
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Emettman
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Re: A cure for insulfrog points?

Post by Emettman »

kebang wrote:Emettman - Will the blade against the relevant stock rail not provide "switched" power, without going to the disruption of providing a separate switching power supply?
Yes, it's a question of the reliability of the contact.
Mine was an exhibition layout frequently moved and stored, and at an exhibition five minutes trying to fix a balky point feels like and hour!

With DCC I understand that there are one or two extra reasons why relying on blade contact alone is not recommended, but I'll leave that to the experts in the field.

Chris
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Bufferstop
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Re: A cure for insulfrog points?

Post by Bufferstop »

Emettman wrote: On the new "universal" Peco frog, this seems to have little or nothing to do with eliminating dead-frog issues,and everything about removing the need for good electrical contact between the point blade and its stock rail. at the cost of the point no longer providing isolation in the non-selected direction.
In their info they do suggest that users of DC may cut the bond between stock rail and blade to restore isolation of sidings, so they are now making the default state DCC ready. The floating frog can be powered by an auxiliary switch if you run V short locos. I'm sure the bonding of blades and stock rails is to prevent the rail to blade contact, good for around 1amp or so, carrying a just less than tripping current from a more powerful DCC unit. I'm sure a current of 4.9A from a 5A DCC power supply, and a high resistance low contact pressure, junction of blade and stock rail could do a fair impression of resistance soldering. Something Peco would be keen to avoid happening.
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kebang
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Joined: Fri Jun 13, 2008 11:59 am
Location: Bohol, Philippines

Re: A cure for insulfrog points?

Post by kebang »

I did some searches on the forum & realised that we covered this topic pretty well in 2016 'electronics' forum. I had actually contributed but had forgotten :oops: . (In my defence my contributions were by way of using TCS keep alive decoders to solve the problem)
I've ordered some 'Silver Conductive Glue Wire Electrically Paste Paint' to test how effective/resilient this is.
It will take around 3 weeks to arrive. When it does I'll run some tests & report the results here. If this stuff is no good for this job. I'll shop around when I am in the UK (May 2018) for something better - Any suggestions welcomed.
Bufferstop - I can't find the universal points you mentioned, can you direct me? (I'd also like to take a look at them when I'm in the UK)
Emettman - thanks for the clarification on just using the blades as switches
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