Full Version: modelsof1900's Get off yer duff Challenge (Part III)
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Today I would like to start a thirt part of the contest - digitalizing of my N&W class M 4-8-0 with this picture how the model looked in August 2016 before the first movement was done.

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I think that this is a nice model imported by Sunset models and now around 18 years in my shocase. Really, it was time to digitalize it and to add some motive power for my 1930 trains. The prototype was built a first time in 1906 already however they were coupled with 6-axle tenders not before 1930/35 so that I ought to use it only with my 1930 (+) freight train. However this is the time where I did not have an own digitalized model loco fitting this time - until now. However some more models will follow!
First modifications of model are ...

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... a too wide distance from engine to tender,

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... and a wrong hight of foot board on tender and the missing cab apron, which were to correct!
This is the result, a lowered foot board and a new shoveling bord and an added cab apron.

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Or seen from the side.

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This picture shows a good realized solution on the model. The wheels are relatively softly sprung so the wheels follow also heavy track unevennesses without problems!

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Adding a working front coupler without the large Kadee coupler box where I glued a very thin phosphor-bronce wire into a pre-drilled hole of shaft.

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However the end of spring wire must be fixed in a hole or a slot where it is freely movababely!

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To be continued.
Now a few preparations for power pick-up. The tender is a simple thing.

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This is the ordinary way on tender trucks with power feeders on the insulated wheels and additional two bolts to avoid the 360 degree rotation of trucks. I modified additionally the axle bearings on the trucks in order to reduce the friction by the axial pressure of power feeders and I could see with some rolling tests that this change helped for a better rolling of trucks.

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(I'm sure that I have shown this solution in forum here however I did not find this post.)
Because I love to use not visible power feeders I have had to made some small changes on the wheel sets; they had a too wide lateral play in the frame. So I added some thin metal rings as for reducing the lateral play. However how were they to install without to pull the wheels from the axles? I made some open metal rings, ...

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flattened them to the wished thickness, ...

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I spread these and pressed them back to a flat ring with the bearings. The result is absolutely satisfying ...

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and you see also the only wheelset with the original lateral play. However this will not be a problem after first running tests. All other wheelsets have a well reduced axial play and this is that what I needed for the additional electrical power contacts which will glide on inside of insulated wheel rims.

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Next step to install the additional power feeders on the loco was to insert insulated metal bushings into this side wall of frame with the insulated wheels.

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Making of small contact pins and contact springs, ...

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which also were to mount insolated against the frame and where I fixed a power line for the the connection to the decoder.

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Again an additionally positive result, the loco can run now also without the tender because both sides of wheels can be connected with the motor and where the new contacts are not visible from outside or from underside of frame. Sorry, I hate power feeders mounted under the bottom plate of frame which are looking like spider legs!

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To be continued.
Last changes before digitalizing yet. Shorten a too long fixing screw on excenters.

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Repairs where I have had a too fast grasp ...

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... and shorten of a too long combination lever which was going over the rails near to zero.

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And now the digitalizing with problems which I never have surmised and which I not could picture with all its consequence!
First I searched the best speaker which I could set with some modifications into the smoke box because my locos must generate their sound like the prototypes at smokestack!

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The speaker is clamped into the smokebox and to see already the wiring behind the skokebox front for frontlamp and classification lamps.

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And all components were working with my TCS WOW-sound decoders - motor, sound, lighting!
This is a picture how I built up my test installation on a cleaned work table. This picture was also a proof for TCS that all the parts of this digitalizing project did well and correctly work. Then after that the problems did came!

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I tested that again using different speakers - and switches it off on evening. Please watch also that TCS offers als a docoder version with a kee-alive unit that you see on picture in center connected with two wires only. All was ok at this moment on evening.

However how do you start this installation on next morning? Power switch on at command station - and the decoder was burnt!

What was the reason for that? I checked all components, no shorts - and starting with my second decoder again with a step by step activation and - all is working like wished! I switched off and on, I tested speakers again - and all were working like before. Power off in evening.
Power on in the morning - and the second decoder was burnt!

Honestly I ought to write that two decoders where burnt before this moments where I worked with modified speakers and where I guessed that I have set reasons for burning of decoders. Because I check especially my digitalizing very extensively with tests of components and by measurings against shorts I'm sure that I not fave give a reason for these burnt decoders. I replaced the first modified speaker by a new one which I rebuilt also and it worked. My LED lighting worked, the motor rotated and drove the engine on the roll test stand - all worked correctly while single tests and including also in combination - and each time the decoders burnt with the first pwer on on next morning! Did set the fix connected keep-alive unit a reason after a full discharging over night?
Believe me, I was desperate!

A friend suggested to replace all parts and components of this work and to make a new start from zero by use of an old test decoder where a loss would not be a large failure. And so I did it!

To be continued.
Sorry, not written for a long time and there is not a progress with my N&W class M.
I see all the progress on your models and I'm not sure if I can finish this loco.
Really, after some heavy mistakes with decoders I was sure that the problem was solved. Because not so good running of loco I replaced the motor and now the gear with large tooths sounds louder then before and the loco does not run many better - until today where I new decode problem stopped all activities. For a long time I did not found a non-fixed short in the system until I removed all additional power feeders on the loco and removed all the not used wiring again.
However I see that the running performance of the model is not that what this decoder should do. There are speed changes in acceleration and more yet while deceleration and that also with two different decoders.
What could be the reason for this untypical performance? Now I'm working since four weeks with this model and I'm not one step closer to finishing as before.
Maybe that I start tomorrow with a simple basic wiring - two wires from rail to decoder and two more from the decoder to motor, without lights, without sound. And maybe that I will start with a 100 percent new wiring hoping that I can eliminate possiblely undetected shorts or creeping current between lights, sound and motor powering. This is the first time that I did not found a reason for a problem in spite of tests over tests and attempts with different parts in this digitalizing project.
In moment I'm not very lucky with this model. But here the last picture of last mechanical modification at this model, a new motor with a divided power line from motor to gear. This works well, smoothly and gently.

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