Quartering

[Ian F]

Having completed one 57xx (2mm etch) and got it running (OK ish) with the quartering tool jig I did struggle a little with the jig. Recently building another and wondered if there is an alternative way without using the jig? I have had some advice about marking the wheels with a sharpie so I can see when all in line but I was thinking about how to 'compress' the wheel set into the muffs evenly without using the jig. The obvious one that springs to mind is the small vice - any replies comments would be welcome on how people quarter their 2mm models.

Thanks

Ian 

[Richard Hall]

Maun parallel jaw pliers are one of my favourite all round tools.  I don't currently have one which will do wheel fitting but I have been meaning to buy a suitable set for ages. You will also need the little slotted shims so you don't squeeze the frame bush between the muff and the wheel back and lock everything solid, but the same applies with the quartering tool.

 

https://www.maunindustries.com/parallel-pliers/smooth-jaw-parallel-pliers/

 

Richard

[Caley Jim]

In the December/2006 issue of the Magazine I had an article entitled 'Coupled Chassis Mechanics' in which I discussed how quartering works and described how I achieve this without any jigs or tools.  My method has worked successfully on 10 chassis so far,  (the 11th is a 2-2-2WT).  If you don't have the Magazine back number archive (why not I ask!) I can PM you the article.

 

Jim

[Ian F]

Hi Jim,

I have that article - thanks. I will try this method now, my only question is if the muffs are opened slightly enabling the wheels to be moved individually will there be any wheel slip? My guess is - "not if the connecting rods are fitted correctly to correctly quartered wheels"? 

[CF MRC]

Not sure what is in Jim’s article, but I am a firm believer in wheels being a very tight fit in their muffs. I have found that adding super glue down a central hole was not invariably successful at holding the wheels. However, it is useful to have an ‘easy’ set of spare muffs that can be used to check that the wheels and coupling rods will work together. How to adjust the coupling rod holes has been written up many times, but one given is that the coupling rod holes on the gear-driven wheel must never be opened out other than for a good running fit on the crank pin. Once the wheels and rods are OK then I record wheel and rod positions, L & R and position (front to back) with identifying scratches on the backside of the tyres (e.g. I, II, III, etc). That way the whole assembly should go back together OK. 
 

The definitive muffs need to have a slight countersink on the opening and the axle ends must be smooth, so that they align easily. The wheels are then squeezed into place a small distance using an accurate vice, with only the wheel centres located on the jaws at one end.  The position of the cranks is set (most companies had RH lead - but not the LNWR). with the wheels running at, say,  6’ gauge.  With the wheels quartered, the rods should still work as before, as the chassis is pushed along the bench. As the wheels are squeezed together to the correct back to back, there will need to be removable C shims inserted behind the wheels, next to the frames, to get the clearances equidistant.  Little bits of electrical insulation are useful as temporary coupling rod fixings, to allow the rods to be removed and replaced frequently during setting up.

 

The significant force used to squeeze up the wheels means that they will not change either quarter of back to back once set. Admittedly, I do tend to make CF locos a bit bomb-proof in this regard, but with high mileages and sometimes frequent wheel cleaning it saves a lot of grief down the line. 
 

Tim
 

 

Edited December 11, 2022 by CF MRC

[Caley Jim]

Running a 1.5mm drill through by hand (drill in one pin vice, muff in another) doesn't open the holes out too much, but makes inserting the axle easier and once you put the gear on the driven axle I find that tightens the grip on the axle..  I actually only use Association muffs on the driven wheels, using some 2.5mm od. styrene tubing (evergreen I think) for the others.  Once you get everything running smoothly I've found cyano is OK.  That's one of the reasons I file a slight chamfered flat on the end of the stub axle, to give a wee bit of a key.  I would agree with Tim that slightly countersinking the opening of the muffs helps in inserting the axle.

 

Jim