Lord Nelson Split frame decoder installation
Tools & Equipment
1. Shrink tube
2. Junior hacksaw
3. soldering iron
4. Dremel or similar motor tool
5. Fine Screw drivers
6. Determination
7 . digital Camera
The take down of the chassis is very straight forward. Remove the body it's normally a small screw front and rear, screw the small screws into the body so you don't loose them. Take a photo of the motion both sides so you have a reference for reassembly. Ease off but don't remove the chassis halfs screws. Using a screw driver gently ease off the cylinders, they should come off without too much force, Bachmann sell spares so if you do damage them it's not really a major issue. The motion and wheels are also held to the body by a motion bracket, so unscrew that you'll need a fine screw driver, so you'll quickly realise you should have invested in a good set of precision screw drivers, not those cheap and nasty jewellers screws drivers that are so popular. Put the screws aside in a secure container. Remove the base plate, and then the wheel set and the motion complete, using a piece of tape mark the front of the wheel set, so that when your finished, your assembly can go back the same way. Now remove the chassis screws, knock out the insulation pins and collars, and gently lever the chassis apart. Remove the small plastic base plate tee pieces put them in your safe container. You will now have two chassis half's, remove the motor and put aside don't damage the insulation on the body, remove the gear, and use a rag to remove all the oil and grease from the chassis. Remove and discard the two small springs and felt pads using to transmit power to the motor. Your loco has now been reduced to a pile of bits, so from here on it can only get better !!
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In the chassis body you'll find two blind holes used to retain the springs, use your Dremel and grind this area to give more clearance to the motor terminals.
You'll need this as your going to be fitting shrink tube to the motor terminals and we don't want these trapped and pinched on reassembly as it could lead to a short. Next using the insulation pins only place the two chassis half's together. Determine where your going to mount your decoder. Certain type of decoders are much better than others for this type of installation, I prefer the TCS M1 without a plug, it's tiny, the decoder is insulated, and this decoder has great specifications, especially the new ones with B-EMF, and the cost is right to at around £18.00. With the Lord Nelson you will quickly determine that the decoder will not fit at either end, and the best way of accommodating the decoder is at the top of the chassis.
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These photos were taken 7years ago when the size of decoders were much larger than to day so a larger cut-out was required. In 2001 the smallest decoder was the Digitrax Dn121 things have moved on a bit and the TCS M1 is about 1/3 of this size. Fortunately things have moved on a bit with Digital photography so I sorry for the poor quality of the photo's. Notice too that the wheel set has been removed but the motion is still attached to the body. Back then it was quite common to remove the circlip from the centre driver and remove the wheel set that way. Of course this was quite easy to disassemble but not so easy to reassemble, so avoid this method if you can.
Cut away a section from the top of the chassis with you junior hacksaw, enough for the decoder and some double side tape and wires. If when your sawing you go a bit crooked, reverse your chassis in the vice and you'll straighten out your cut, mark a line before you cut and of course stay away from those all important chassis pin holes. Tidy up you handy work with a file and remove all burrs, use a rose and gentry brake the corners of the holes holding the insulation pins, it makes reassembly much easier.
Installation
Cut two short pieces of shrink tube, I use 1.25mm (short and in this case the shorter the better).Measure it that the shrink tube is no longer than from the terminal to the outside of the chassis. Place them over the grey and orange wires and then solder to the motor terminals. Test your joint and then fit the shrink tube over the joints push right up tight to the motor body and then use heat and shrink in place. Fit the motor in to the body, and then the drive gear, and lubricate with some white grease.
Now fit the tee base plate holders the insulation pins and collars to one side of the chassis (this is the only difficult bit) and then marry the tow half's of the chassis making sure the motor is seated perfectly. Using a knife and a screw driver it's easy to fit the insulation collars if they get misplaced and with practice you can do the same with the tee base plate holders, when your happy that the assembly is good refit the screws to the insulation pins but
do not tighten them. Now is a good time to make sure the wires are not pinched in the chassis, and that the motor gear rotates as it should. If all is well then refit the wheel set, the cylinders, and the motion bracket then secure with the base plate. Check you assembly by turning the fly wheel and making sure the motion works as it should. Check the decoders fit in the chassis, in this installation it's good practice to shorten any unused wires so snip short the yellow white and blue wires your not going to use them, put the wire aside for future use. Cut the blue wire just a little shorter and then encase then all in shrink tube. The festoon of wire has shrink !
The Red and black wires are used to collect current from the chassis half's, I attach them to small piece of printed circuit board and these are forced into the chassis with the copper side touching the half used for current collection. Mount your decoder on double sided tape and test on the programming track, and then remount the body.
Easy isn't it
Now if you don't want to go to that trouble send your Lord Nelson to Stuart Debeer at the model Yard he charges around £40 quid and it might save you a lot of effort
"if you don't want to get your hands dirty" or "your a member of the plug and play society"
