re-wheeling a 14xx Hornby

"piemanlarger" wrote

Be careful Simon, I rewheeled one some time ago to avoid traction tyres and the thing would barely pull itself along afterwards.

John.

I am surprised, mine has not traction tyres now and it seems ok with the two auto coaches which is the most work it will have to do.

What wheels did you use for the converstion John?

If it does what you want it to, I'd leave it as is. I removed the tyres from my Fowler 2-6-4T and it runs with less of a wobble, better pickup and adequate traction for 3 suburban coaches.

"MartinS" wrote

The latest Fowler 2-6-4T is streets ahead of the old model and is no longer fitted with traction tyres, but it does need a tad extra weighting to allow it to run really smoothly and pull a reasonable train.

Very much recommended! :-)

John.

I'm sure it is, John, but I'll have to make do with what I've got! I have the new Black 5, but it slips a little with 14 wagons.

In message , MartinS writes

??? What sort of wagons are you putting behind it? How flat is your layout?

I'm most surprised that the Black 5 slips with only 14 wagons behind it. My Bachmann 56XX 0-6-2T locos will pull 45 wagons up a 1 in 78 incline with no problems, and I would expect the Black 5 to perform similarly.

An assortment of Hornby, Bachmann, Airfix, Mainline 4-wheelers, but all with new wheels. It's OK once it's up to speed; my layout is flat, but has 2nd and 3rd radius curves. It runs slower on the curves (using a basic MRC280 controller). A bit of slip on starting is prototypical!

I also managed to clean up my old Hornby tender-drive Black 5 and get it running, but it needs an awful lot of juice to run at even a moderate speed. I couldn't double head them!

=>An assortment of Hornby, Bachmann, Airfix, Mainline 4-wheelers, but all =>with new wheels.

How well do those wheels spin? Will the wagons roll down a 1 in 100 incline (better: 1 in 200) on their own? If not, the bearings and axle ends need some work. Use a coned reamer to bring each bearing to a 60 deg. cone. All axle ends should be pointed and polished. I've noticed that many wheel sets offered in the UK have squared off axle ends. These may look prototypical, but they don't roll very well. The axles should also have just enough end-play to notice, not enough to let the wgaon slide side to side. Lubricate with a dry lubricant, such as graphite or Teflon powder. Also weight the wagons to a consistent weight. The NMRA recommended practice is a good place to start: 1 oz plus 1/2oz for every inch of length. (Metric version: 30 + 1/2

• length in mm). NEM also has a rec. weighting practice. However consistency is more important than some standard.

Also, the loco may not be well balanced. Weight may actually work against you if it's badly distributed. The centre of gravity should be as close to the centre of the driving-wheel base as possible. It's worth shifting weight around inside the boiler to achieve that end. Weakening or removing the spring that holds the pony truck down onto the track helps, too. Some experiments published in MR about 25 years ago showed that CG on the last driver cut the pulling power of a 2-8-0 in half. Significant, that. :-)

Wolf Kirchmeir ................................. If you didn't want to go to Chicago, why did you get on this train? (Garrison Keillor)

A GWR 14xx doesn't have a pony truck. The rear axle is a radial one. If you reduce the weight carried by this axle you will make the loco very unstable. If the Hornby model is anything like the original Airfix version then there is simply no way of reducing the weight carried by the radial axle as the chassis is constructed as if it's a rigid 0-6-0. The rear coupled wheels may not even touch the rails, so that the loco is more like an 0-2-2!

The optimum method of achieving maximum tractive affort on a 14xx is to compensate the radial axle with the rear coupled axle using a central beam with its pivot point at about 25/75 along the beam (nearer to the couple axle). That way you maintain control over the position of the rear buffer beam both vertically and horizontally while keeping as much weight as possible on the driven axles.

Wolf Kirchmeir wrote:

snip

=>A GWR 14xx doesn't have a pony truck. The rear axle is a radial one. If =>you reduce the weight carried by this axle you will make the loco very =>unstable. If the Hornby model is anything like the original Airfix =>version then there is simply no way of reducing the weight carried by =>the radial axle as the chassis is constructed as if it's a rigid 0-6-0. =>The rear coupled wheels may not even touch the rails, so that the loco =>is more like an 0-2-2!

Well, if that's the case, the CG isn't in the right place, is it? The aim is to get the weight of the loco distributed among the driving axles as evenly as possible. I referred to the pony truck 'cuz my advice was generic, not limited to 0-6-0s.

I concur with your advice to compensate/equalise/etc - that's the best way to keep the weight on the drivers. But the weight should carried by all drivers equally. That's all I intended, really, and if my post confused anybody, sorry about that.

Wolf Kirchmeir ................................. If you didn't want to go to Chicago, why did you get on this train? (Garrison Keillor)

If the chassis is rigid and the middle axle - which happens to be the rear coupled one on a 14xx - is higher than the outer two, no amount of messing about with the CoG will get the middle wheels to touch the rails!

Wolf Kirchmeir wrote:

=>If the chassis is rigid and the middle axle - which happens to be the =>rear coupled one on a 14xx - is higher than the outer two, no amount of =>messing about with the CoG will get the middle wheels to touch the =>rails!

Yeah, sure, so?

Wolf Kirchmeir ................................. If you didn't want to go to Chicago, why did you get on this train? (Garrison Keillor)

Only one pair of wheels doing the driving!!

The original problem that started this thread was that of the loco not being able to pull a reasonable train.

Wolf Kirchmeir wrote:

No it wasn't, I asked how to re-wheel a 14xx as I dont want traction tyres on it. I hauls two auto coaches ok, just sits like an easy rider due to the grooves in the wheels for the tyres!

"piemanlarger" wrote

Another option Simon. Fit new traction tyres (available from Hornby) after thoroughly degreasing the grooves and the tyres. Then, when properly fitted, secure in place at around 45º intervals around the wheel with the tiniest spot of thin superglue. This should stop the loco from shedding the tyres.

John.

=3D>

=3D>"piemanlarger" wrote =3D>

=3D>> No it wasn't, I asked how to re-wheel a 14xx as I dont want tracti= on tyres =3D>> on it. I hauls two auto coaches ok, just sits like an easy rider d= ue to =3D>the =3D>> grooves in the wheels for the tyres! =3D>

=3D>Another option Simon. Fit new traction tyres (available from Hornby= ) after =3D>thoroughly degreasing the grooves and the tyres. Then, when properl= y =3D>fitted, secure in place at around 45=BA intervals around the wheel w= ith the =3D>tiniest spot of thin superglue. This should stop the loco from shed= ding the =3D>tyres. =3D>

=3D>John.

A third option: degrease as above, then fill the tire (tyre) grooves wit= h epoxy. When cured, file smooth.

Wolf Kirchmeir ................................. If you didn't want to go to Chicago, why did you get on this train? (Garrison Keillor)

That's hardly going to improve current collection!

Greg,

I was more worried about how round the resulting wheels would be. :-)

Jim.

Errr, not particularly well. ;-) The original problem was lack of pulling power(?) Current collection plays a small part in this, intermittent collection from having only four wheels collecting is going to reduce pulling power considerably!

Fair point.