Replace the terminals on a Piko Point Motor

[JimmyB]

This is how I replaced the terminal block on a Piko Point Motor, I am NOT a professional electronics person, so any (constructive) criticism is welcome. I used the terminal block as supplied by RC Trains for use on LGB point motors, it seems to fit perfectly.

Remove the SIX screws securing the top.


This is what the inside looks like, similar to an LGB point motor, but this has a rubber seal.


The driven rack is fitted into the seal so these are removed as a single item, note there are two (one each side) retaining spacers.


The motor unit is now removed, the two side plates will almost certainly fall off, also note that the drive pinion has a small "stop" that is on the underside.


On assembly the side plates slot into the drive with the long ends at the pinion end. You can just see the "stop" on the pinion, this limits the movement "back and forth", position is vital on assembly.


Carefully desolder the winding connections, I did a resistance test (2.3 ohm), this is to ensure that reconnected a similar value is achieved before re-assembly.


TBC!!

 

[JimmyB]

Part Two!

With the winding de-soldered, I filed down the top of the lugs so the old terminal block came out.


The new block is inserted, and the windings ends soldered in position, at this stage I checked the resistance, at the terminal block, and was almost identical, so I was content a good connection was made. I then removed the excess from the terminal block lugs.


The motor assembly is dropped in to place (just like that ). Points (puns ) to watch out for:

a) If the motor does not sit flat, do not force it, the two side plates and the pinion have to be in the correct position, with the stop against one side.
b) The two spacers mentioned earlier, ensure they are up against the seal, other wise the top will not fit correctly.
c) If the pinion "stop" one side, the arrow on the rack should be at the other side.


If you are brave, you could apply power now to test it, but chances are the rack will jump out of position. So fully assemble, tighten all six screws and test - good luck.

Though I have never changed the block on an LGB point motor, I have stripped them right down, and they are very similar, so most of this can be applied to an LGB motor.

 

[Paul M]

Very useful, thanks for the advice

 

[PhilP]

And you know where to get the terminals...

Exeter Garden Railway show tomorrow, at the Matford Centre, or ping me a message..

Open bank holiday Mondays, book early for Chr*stm*s!

PhilP.

 

[dunnyrail]

Interesting to see the Piko one pulled apart JimmyB , could almost be an LGB one so similar are they except for the rubber seal. That seal a good step up on the design. Having restored a few LGB ones I can certainly confirm these instructions will work for both makes.