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Discussion Starter · #1 ·
I have converted a fair few old locomotives ,mainly Fleischmann and Roco
The 70's Fleischmann Locomotives have the motor body electrically connected to the -ve motor terminal
and in most cases to the chassis.The chassis is the conductor for the lighting circuit.
Easy fixed for DCC conversion by the fitting of a replacement motor shield which is insulated (Flm part no 504730)

My question is .

With the Electric Locomotives , that have a working pantograph pick up system , the motor electricals are reversed.The positive motor terminal is electrically connected to the body of the motor , but the motor bogie has no electrical connection to the track. The wheels are insulted from the axles.Power pickups from this bogie are on the +ve side but are connected to the switch for selecting Pantograph power or Track Power.I hope I have described that OK

When converting to DCC -Disconnect any power pickup from the pantograph.Motor isolated from any track power pickup etc.

The questionable bit!

The Orange wire from the Decoder +ve connection of the motor (to save $17 + Frt) not using the insulted motor shield.The motor body is now electrically connected to the Orange wire. I have made sure that any metal component Cannot accidentally contact the motor (insulated the weights etc) The metal chassis is connected to the -ve side of the power pickup to run the lights with the original connections on half wave power.

I have 3 E Loks that have been done this way with no grief - So Far


Should I leave them as they are or should I use the Insulated motor shield?
 

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QUOTE (zmil @ 22 Jun 2008, 11:19) <{POST_SNAPBACK}>I have converted a fair few old locomotives ,mainly Fleischmann and Roco
The 70's Fleischmann Locomotives have the motor body electrically connected to the -ve motor terminal
and in most cases to the chassis.The chassis is the conductor for the lighting circuit.
Easy fixed for DCC conversion by the fitting of a replacement motor shield which is insulated (Flm part no 504730)

My question is .

With the Electric Locomotives , that have a working pantograph pick up system , the motor electricals are reversed.The positive motor terminal is electrically connected to the body of the motor , but the motor bogie has no electrical connection to the track. The wheels are insulted from the axles.Power pickups from this bogie are on the +ve side but are connected to the switch for selecting Pantograph power or Track Power.I hope I have described that OK

When converting to DCC -Disconnect any power pickup from the pantograph.Motor isolated from any track power pickup etc.

The questionable bit!

The Orange wire from the Decoder +ve connection of the motor (to save $17 + Frt) not using the insulted motor shield.The motor body is now electrically connected to the Orange wire. I have made sure that any metal component Cannot accidentally contact the motor (insulated the weights etc) The metal chassis is connected to the -ve side of the power pickup to run the lights with the original connections on half wave power.

I have 3 E Loks that have been done this way with no grief - So Far


Should I leave them as they are or should I use the Insulated motor shield?


***The risk is up to you: I would never do this with a clients locomotive.... or one of my own. Murphys law is too often proven right.

What you are doing is technically correct but practically risky to a degree.... The decision is yours.

A similar catch 22 can exist with older US Brass where pickup is shared by chassis/live wheels one side of the loco and other side of the tender, with an insulated drawbar between them... if two are coupled using metal couplers then a loco to loco short can happen... I've actually seen a Kadee red hot because of this problem!

With your current method it does of course work but you are at a much higher risk of decoder death.... ie:

(1) Any derailment that connects body/chassis to track in any way will possibly damage the decoder (orange touches track power).
(2) Any metal part of one locomotive wired conventionally touches a metal part of a non-conventionally wired locomotive (ie buffer to buffer) and a path will possibly exist from track to orange wire.

Kind regards
Richard
DCCconcepts
 

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Discussion Starter · #3 ·
Yes I can see that could be a problem

In this case the Motor bogie is in a plastic holder ,which is also the detailed side frame of the bogie ,this is the part that pivots in the chassis. The motor is not connected to the chassis (to allow for independent power from the pantograph in the original analog ) and the plastic side frame extends lower than the metal part of the motor frame.It shouldn't touch the track even in a derailment . But like you say Murphy's Law !

I think I will invest in the isolating motor shields!!

Many thanks for the decoders by the way Richard (very quick delivery)

Love that new BEMF

I put 1 in a loco I had previously converted and could not believe the difference in running from the old T1 which I thought I had tweeked quite well

Regards Zmil
 

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QUOTE (zmil @ 22 Jun 2008, 03:19) <{POST_SNAPBACK}>Should I leave them as they are or should I use the Insulated motor shield?

I can only echo Richards comments or you may end up with frying chips !

There is a strong possibility with a derailment that the motor chassis block could come in contact with the running rails. Also, there are a few loco's that have a completely metal chassis, such as the NS OHE.

For the sake of the insulated motor backplate it's not IMHO worth the small cost saving - BTW there are actually about five different types of backplate.

Having said that, although the older three-pole motor, regarded by many as poor actually runs very well with a well set up decent decoder - as long as everything is clean, especially the commutator segment gaps & free running.

Another trick I've found with these older locos is (only if you tend to "pull" in one direction though) is to swop the wheels around on the motor bogie so that the two traction tyres are on the "rear" axel. Make the gear train mesh better & increases the haulage capacity.
 

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Discussion Starter · #5 ·
QUOTE (Brian Considine @ 22 Jun 2008, 14:23) <{POST_SNAPBACK}>I can only echo Richards comments or you may end up with frying chips !

There is a strong possibility with a derailment that the motor chassis block could come in contact with the running rails. Also, there are a few loco's that have a completely metal chassis, such as the NS OHE.

For the sake of the insulated motor backplate it's not IMHO worth the small cost saving - BTW there are actually about five different types of backplate.

Having said that, although the older three-pole motor, regarded by many as poor actually runs very well with a well set up decent decoder - as long as everything is clean, especially the commutator segment gaps & free running.

Another trick I've found with these older locos is (only if you tend to "pull" in one direction though) is to swop the wheels around on the motor bogie so that the two traction tyres are on the "rear" axel. Make the gear train mesh better & increases the haulage capacity.

Hi Brian thanks
I'm looking for a insulated shield for a BR132 Model no.4369 (old 1632) made between 1968-86 it has slightly different mounting points than the conventional motor , that can utilize the 504730 Its difficult without seeing a picture to try and match the insulated motor shield. Do you have pictures of the parts?
Regards Zmil
 

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QUOTE (zmil @ 22 Jun 2008, 08:26) <{POST_SNAPBACK}>Hi Brian thanks
I'm looking for a insulated shield for a BR132 Model no.4369 (old 1632) made between 1968-86 it has slightly different mounting points than the conventional motor , that can utilize the 504730 Its difficult without seeing a picture to try and match the insulated motor shield. Do you have pictures of the parts?
Regards Zmil

Hi - this is the one with the three fixing screws part # 504750.

If you cannot get one locally send me a PM - we have them in stock.
 

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QUOTE (Brian Considine @ 22 Jun 2008, 16:33) <{POST_SNAPBACK}>Hi - this is the one with the three fixing screws part # 504750.

If you cannot get one locally send me a PM - we have them in stock.

Hi Brian
Made a mistake the 504750 is what I have used on most of the conversions but the 4369 loco's motor has different orientation of the 3 screws to fix the motor shield on 1 will line up the second one is close the third is off by about 4 mm
Regards Zmil
 

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Hi again,

It looks like the 4369 & the 4367 are about the only two FLM locos that have this "offset" backplate. We have never converted either of these, although probably done most of the others in the range.

The service sheets seems to suggest that the part number required is 50 4703 but it does not show if it is the insulated one or not (the picture is not too clear). I'll make a couple of call tomorrow & see if I can confirm one way or the other.
 

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Discussion Starter · #9 ·
QUOTE (Brian Considine @ 23 Jun 2008, 01:58) <{POST_SNAPBACK}>Hi again,

It looks like the 4369 & the 4367 are about the only two FLM locos that have this "offset" backplate. We have never converted either of these, although probably done most of the others in the range.

The service sheets seems to suggest that the part number required is 50 4703 but it does not show if it is the insulated one or not (the picture is not too clear). I'll make a couple of call tomorrow & see if I can confirm one way or the other.

Brian I would cut an arm off to get hold of some older Service sheets
per chance do you have any for the 4369 and 4330 in jpg or pdf you could email

Regards zmil
 

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QUOTE (zmil @ 23 Jun 2008, 04:56) <{POST_SNAPBACK}>Brian I would cut an arm off to get hold of some older Service sheets
per chance do you have any for the 4369 and 4330 in jpg or pdf you could email

Regards zmil
No problem - send me a PM with your email address & I will scan & send them to you.
 

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If Brian doesn't want the arm, can I put in a bid since I could do with a third hand for soldering stuff? It would have to be heat resistant though


David
 

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Discussion Starter · #12 ·
QUOTE (dwb @ 24 Jun 2008, 00:58) <{POST_SNAPBACK}>If Brian doesn't want the arm, can I put in a bid since I could do with a third hand for soldering stuff? It would have to be heat resistant though


David

No ! The arm has been saved!

You could use one of those little soldering "helpers"
Not sure what they are really called but they have adjustable alligator clips and even a magnifying glass



I'm kind of attached to my arm


Regards Zmil
 

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QUOTE You could use one of those little soldering "helpers"

I don't know what they are called either but I've seen them on stands at the larger exhibitions I go to.

Glad to hear you and your arm are still attached


David
 

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They're called Helping Hands, £9.99 from Maplins, but I see them in lots of places for about a fiver.
 

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Discussion Starter · #15 ·
QUOTE (poliss @ 25 Jun 2008, 01:09) <{POST_SNAPBACK}>They're called Helping Hands, £9.99 from Maplins, but I see them in lots of places for about a fiver.

This my 3rd one of these They have got a lot cheaper I paid $12.00 from Dick Smith Electronics for the first one

The one you see there I bought from Bunnings ( local Hardware chain set on Australian domination ,probably the world next)
came with a 240v soldering iron ,solder sucker (nice aluminium one) solder in a plastic case for $14.99 (about 7GBP)

Regards Zmil
 
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