Great Chesterford Junction Part Two

I`ve got a bag full of them now.
Gormo

 

Gormo

 

Thanks Jim,
It starts to become a short story with sound effects.....
Gormo

 

G`day Folks,
Here at home over the last twelve months we have been experiencing what we refer to as appliance failure.
Those appliances that you naturally take for granted gradually succumb to their manufactured use by date.
Well this time it was the turn of my main PC......the one with enough grunt to do my video editing and just about anything else I could think of.
I am writing this on my old laptop ,which unfortunately, does not have enough resources to cope with the demands of my video editing software, however it is fine to search the web for a replacement PC.
I have been looking and researching for a few days now and I think I have found a suitable PC.
It will be a step up in terms of computing power so I hope to be back in the saddle as such, in a few days time.
Gormo

 

G`day Folks,
I had to do a little repair on my Hornby Schools Class yesterday.
It`s the Hornby R132 4-4-0 " Cranleigh " 936




A beautiful engine from a long way back and it had a problem with the pinion.
The pinion was slipping on the motor shaft when I first purchased the loco and I fixed it then with some Loctite which worked quite well for a couple of years now.
However yesterday it started slipping again to the point where it would move to the front / end of the motor shaft and disengage with the gears.
Some years ago I bought a pack of various gears and pinions and shafts from our friends in China and I`ve used them for some of my projects.
I took care to order both 8 tooth and 10 tooth pinions which hopefully would be a good match for my Lima and Hornby locos respectively.
You can see from the pic below there is a considerable difference in the thickness of the two parts.....Hornby on the right.



The only problem with my replacement gears is that they are to suit a 2mm shaft whereas the Hornby standard is thicker at around 2.4mm I think.?
So the replacement had to be drilled out to suit the Hornby shaft and then we were away.
Fortunately there is plenty of clearance inside the tender , so the pinion could be simply pushed straight on.



I just gave it a drop of Inox on the gears and then off we went.
The noise factor has decreased and the slow running is better now.......video below



Gormo

 

I now have a Lima tender drive that needs attention......probably a heart transplant, so stay tuned for this one.....I will deliver notes and pics on the operation.
Gormo

 

G`day Folks,
Well back to the Lima tender drive.
A bit of history here.....I bought this drive mechanism some years ago to enable me to convert a Mainline Jubilee locomotive over to tender drive rather than relying on the old inadequate Mainline motor and split axle system.
The motor was removed from the Mainline locomotive thereby turning it into a dummy / rolling chassis.
Jumper wires were added to the split chassis and fed through to the tender to take advantage of the extra pick ups available from the loco wheels.
The Lima chassis is self driving because it has pick ups on all four driving wheels, however the more pick ups the better.
The extra pick ups on the geared wheels are shown below. There are also pick ups that go underneath and pick up current from the axles....or the other set of wheels.
So...essentially the tender can drive without a locomotive attached.......a good design in my opinion.
Unfortunately.....I have an issue with either the Lima armature or it`s magnet.........it is very reluctant to turn under power.
The gear train moves freely when not connected to the motor, so the choice is to persevere with the Lima parts or just do a simple transplant with a new CD motor.



OK we are broken down into parts here.
All parts being made redundant will be kept as spares, especially motor brushes and springs and the armature and magnet.



Below is a test fit for the CD motor.
The motor will be secured initially with a small amount of Super Glue just to hold it in place.
Then the cavity between the motor and the original Lima motor housing, will be filled with hot glue.



My replacement pinion ( 8 teeth ) from our friends in China, has to be shortened.
To make a neat, clean cut ,I push the pinion all the way onto the wrong end of a 2mm drill bit.



Then lock the drill bit into my Dremel, mounted in it`s drill press in the horizontal position



I then start the Dremel and then bring my battery mini drill, also running, to the pinion and eyeball the preferred position to cut.
With both mini drills running at good speed, you will get a very clean cut as opposed to trying to cut through with a knife or snips.
Snips will also cause some compression and distortion of the pinion, so are not really a viable option.



The next stage will be to test the spacing of the pinion between the motor shaft and the Lima housing.
More as it happens
Gormo

 

G`day Ron,
I think the guys that produce the 3D printed motor brackets for CD motors have already got that sewn up mate.
Gormo

 

Carrying on with the procedure, The pinion has been set far enough back on the shaft so that it will not rub on the outer part of the housing.



Not a very good picture, but you can see that the pinion has just enough clearance between itself and the outer housing.



You can see the motor shaft does not make it all the way through the outer bearing, but the bearing is not required for the CD motor




This is the pick up from under the axles.......I thought I would tease out one end of it which appeared to be stuck in the main body of the metal and it released quite easily and I was able to put some tension back into it......more about this pick up later.



The motor is now fitted and just tacked in place with some drops of Super Glue on the inside of the opposite face of the housing.
I have taken advantage of the hole in the top of the housing to feed the wires through.



The gears were loose fitted to check for free movement and they passed with flying colours...
A note about the gears......each gear wheel had it`s teeth cleaned by dipping a stiff nylon brush into Methylated Spirits and brushing across the teeth to remove any gunk
Best to get everything back to square one before putting it back together



The gears were then removed and I filled the cavity surrounding the motor with hot glue.
It ain`t pretty folks, but it works...



When the hot glue had cooled, I refitted the gears and added the retaining clip
Extra feed wires have also been added



Now we have arrived at the point where the motor chassis can be fitted into the tender chassis.
This presented a slight problem.
The central wheels that fit into the tender chassis and free wheel and are purely for looks, are actually too thick for the back of the motor side of the chassis.
One wheel just slightly rubs on the metal motor housing and won`t let the motor chassis seat properly into the tender chassis.
So I rummaged through the parts bin and found a couple of thinner wheels of the same diameter, however their centers had to be drilled out to suit the stub axles.



Before putting the lid on the tender and mating it back up with the loco, I checked the feeder wires from the loco with a multi meter to make sure I had live feeds from the wheels on each side of the loco chassis........nope ....... one wire had broken......probably with all the handling the loco has had in the last couple of days.



So eventually the tender and loco were reunited and ready for a run.
One interesting thing that came out of my electrical testing, was the fact that the pick ups that work off the axles have no effect at all on my configuration......simply because all the wheels on the tender are insulated. The pick ups on the axles would have received a feed through the draw bar from one side of the original Lima loco that had been paired with the tender.
As I am matching with a completely different loco electrical set up........basically it does not work......eventually the penny dropped.......
In a nutshell, my system picks up current from one side of the tender and both sides of the loco, which works well.
So I think I can safely say that when you start to modify things you sometimes create another problem by fixing one problem, which ultimately may lead to even more modification and fixes...... but that`s the challenge......to get all the mods to work and make the damn thing run again.
Speaking of running........a short video below



Gormo

 

Ah yes Phil,
The trusty old hammer......
Gormo