Hornby Ringfield Type 7 Problem

[wensleydaledownunder]

Help!

 

I have a collection of 00 gauge locos and no layout. Every xmas I run a 2nd radius circle around the xmas tree and run a train on it. Last year was a Hornby duchess with tender drive. After a couple of weeks, the motor started to spin with no progress. I assumed some tree debris had clogged up the mechanism and packed it away to service at a later date. This year, I ran my old Hornby 60103 tender drive A3. Serviced it first an the same thing occurred. Pulled the tender apart and found the little white nylon gear on the motor shaft was not gripping the shaft. How can I secure this?

 

Interestingly, an even older Hornby Evening Star bought second hand over 20 years ago and never used has been brought in as substitute and after a quick service runs faultlessly! The difference appears to be a brass gear instead of the nylon one.

 

Thanks in anticipation

[Titan]

I would expect that after a thorough cleaning a tiny drop of loctite or similar will secure it.  What oil are you using? If it is not plastic friendly then the oil could be attacking the gear and causing it to loosen.  Best bet is buying model specific oil, Gaugemaster do some and although per cc it is expensive, it comes in small amounts and it will last a while. Any good model shop should be able to supply you some, including the RC specialists etc.

[JeremyC]

I suggest you examine the gear closely. A loss of fit with a plastic gear suggests it may have split. Look for a crack between a tooth root and the bore. If this is the case then you'd have to track down a spare.

 

Jeremy

Edited December 8, 2014 by JeremyC

[bob hughes60]

I would defintely replace the gear don't use loctite!

You do not say if the tender drive motor has a 3pole or 5pole armature.  The replacement brass gears are different sizes for each type.

S2290 is the 11 tooth brass spur/pivot gear for 3 pole and S2635 is the brass 10 tooth spur/pivot gear for 5 poles.

There is an 11 tooth diecast gear for 3 pole armatures do not touch these with the proverbial bargepole.

I am intrigued by a "nylon" gear I know of no Hornby nylon gear in a tender drive.

Remove the brass gear retainers and black/grey gears.

You can remove the tender wheels by gently levering with a screwdriver.

On the opposite side unscrew the brush retaining arm screws one at atime.

Take care to lift the brush retaining arm off the brush spring slowly so the spring doesn't ping off onto the carpet.

Tap/tip up motor block to get carbon brush out.

Put the motor block over a small vice and tighten the vice around the shaft side of the armature that went though the cover plate.

You now, by gently tapping drift on the new brass gear onto the armature shaft.

One side is tight and one side is a looser fit as the bore is tapered to fit. Put it on loose side first.

I use a no 4 spanner to drive it home as far as I want.

I check it spins freely by spinning with a finger.

If the gear is too tight to the motor block tap end of the shaft downwards.

I always put a SMALL amount of oil on the gear and shaft.

Reassemble but before putting coverplate and brushes etc on I touch the armature face with two DC terminals from the transformer to make sure it spins ok.

Sounds comilcated but isn't.

If you need service sheets  http://www.hornbyguide.com/default.asp or Lendons site have them

I have used loctite 648 but wouldn't again as it sets damn quick (before you get gear along shaft) and in one case it failed so the gear kept spinning around the shaft not driving it.

Cheers

Bob hughes

 

 

The old nylon gear can be levered off (fine bladed screwdriver) and the new brass gear is drifted onto the armature shaft whilst gripping the other end in a small vice.

Edited December 12, 2014 by bob hughes60

[wensleydaledownunder]

Thanks for the replies and advice. I've had a closer look and yes, the white nylon or plastic gear is split. I can actually slide it off the armature with my fingers it is that loose. Answers the question as to why. It has 11 teeth, so looks like I can order a brass replacement, which sounds like the best solution.

[john new]

Having got it out after many years of storage just found same problem on my Flying Scotsman, motor spins fine but does not grip the small gear wheel. Does anyone do this repair? 

[rue_d_etropal]

Hornby used to use that dreadful material for the gear. They always got loose in the end. When I was running shop, I replaced quite few. I think there was a brass replacement. Worth contacting Peters Spares as they are now the main place for spares.

[john new]

Most Hornby tender drive motors were made with the brass gear so I would say that it is still available to use as a replacement.

 

I have done a repair myself on these motors before now when tgese brass gears become loose.

 

The way I did it was to use a philips screwdriver that is just the right size to sit over the gear, tap it a few times with a hammer ( not too hard ) so that some of the brass is pushed towards the middle.

 

This probably sounds crazy to some of you but trust me, it works.

 

Once the 1st taps with the screwdriver and hammer have been done, try it for a fit on the armature shaft, if its not tight enough remove the gear again and turn it just enough to put a 2nd set of tappings into the middle like the 1st time so that you have 8 bits of brass pushed into the centre.

 

Then push the gear back onto the armature shaft, it should now be tight enough.

 

My next step is to set it up on the end of a pair of pliers just enough for the shaft to come out through the gear.  Tap it gently on the other end of the shaft where the armature segments will be make sure you leave a small enough gap on the gear side so that it can be oiled and will turn freely.

 

Once this is done, reassemble the remaining gears and the retainer onto the motor block and then reassemble the rest of the motor if the brushes and springs were removed during the repair then once the motor brushes and springs are refitted, test the motor under power.

 

The gears should now all turn together and turn the wheels.

 

Hope this helps.

This one is white so I don't think it is brass. (Loco not to hand at present to recheck).

[Pandora]

The loose gear issue on the Ringfield shaft  is an old  problem  resurfaced. The Class 86 

was also affected,  I was warned of this by the owner of an exhibition layout, he sent his large fleet of class 86 locos back to Hornby to have a the gear replaced on each loco.

I am struggling to recall the details, but I think  the 5-pole Ringfield motors were mentioned,  3-pole Ringfields  being "safe". 

Edited August 21, 2018 by Pandora

[hallmodelspares]

As a slight mod in 1990's Hornby fitted type 6 and 7 ringfields both steam and diesels with a grey spur main gear which is not plastic it is in fact alloy cast similar to actual metal on Hornby chassis etc. The problem is it expands easily loosing grip and will fall off the shaft. This was resolved after the update from 2000 onwards with the introduction of pickups on the motors and brass gears being fitted as standard then. The 5 pole had quality issues with the wheels as they redesigned the wheels to interchange gears between 3 and 5 pole units but they more often failed due to plastic quality and very often fell apart with little use.