Finney7 - 4200G Group Std Tender Build - Scale7

[adrian]

I picked up some of this as a trial to replace vac hoses.
Course Simulated Conduit 1.9mm Silver Colour (45cm) | Prime-Miniatures
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I do recommend adding an inner copper wire core as it can kink quite easily.

Interesting - thanks for posting. I've been looking at using guitar strings - which look extremely similar. The larger sizes have a nickel wire wrapping and have a spring steel core so not very flexible but once bent into shape it holds it's shape very well. Still cheap and easy to purchase ( ~£1 a string from any music shop) so always worth having a variety of sizes in stock.

I have tried sleeving it with heat shrink tubing to give it that rubber hose finish but unfortunately the heat shrink wall thickness is too great and you loose all the corrugation. So still work in progress.

 

[chigley]

following you build with interest Adrian, im building the low front version. regarding the hoses i bought a pack of mamod drive springs on that well known site. Ken

 

[Scale7JB]

Looking great, Adrian.

Makes me want to start my pair.

JB.

 

[Renovater]

For the bearings and the electrical current passing through, you need to use electrical grease otherwise it just won't work. There may well be current passing in a new bearing but that won't last long. I've tried this myself, you have to have the right grease.

 

[adrian]

Just to tie up a few loose ends. I managed to strip the tender down and clean it for painting. I decided to apply a grey etch primer before it tarnished again, but this will be then put in the cabinet whilst I build the loco before it gets a top coat.

 

[simond]

For the bearings and the electrical current passing through, you need to use electrical grease otherwise it just won't work. There may well be current passing in a new bearing but that won't last long. I've tried this myself, you have to have the right grease.

This observation surprises me. I built a 28xx some years back, with split frames / axles for the tender. Pickup is from the axle bearings which are tight 2-3 turn spirals of n/s wire, integral with the springing. The bearings are lubricated with Wahl clipper oil, which is easily available in convenient containers. I’ve had no issues with pickup.

Standard “electrical grease” (eg “electrolube”) is not conductive (30kV/mm), conductive grease tends to be carbon loaded, with quoted point to point resistance of around 400 ohm, which is still pretty high by our standards.

what grease are you using?

Atb
Simon

 

[Scale7JB]

This observation surprises me. I built a 28xx some years back, with split frames / axles for the tender. Pickup is from the axle bearings which are tight 2-3 turn spirals of n/s wire, integral with the springing. The bearings are lubricated with Wahl clipper oil, which is easily available in convenient containers. I’ve had no issues with pickup.

Standard “electrical grease” (eg “electrolube”) is not conductive (30kV/mm), conductive grease tends to be carbon loaded, with quoted point to point resistance of around 400 ohm, which is still pretty high by our standards.

what grease are you using?

Atb
Simon

I have to admit, I have quite a few locos with split axle, using standard gear oil, and the pickup is beyond fine.

JB.

 

[Scale7JB]

Lovely work on the Tender by the way Adrian.

Must not start mine yet, must not start mine yet….!

JB.