billbedford

You are not right, in fact the designer couldn't really get much more muzak into the space he had to work with

I would check that the worm is not catching on the motor or supports in one direction.

To even have a 'spares box' you can be certain the said author has failed to build a great many kits before he got to the subject of the article. To be honest I find that most constructional articles in magazines, and for that matter much of the content of web forums, have more to do with publicly validating the author's modelling skills than presenting useful instructions for other modellers.

If you had been following this thread, you would have know it was a fairly simple fix to get your loco running. See posts 787 & 791.

There are GAs and frame plans for the class C 0-4-4T and the class D 0-6-4T in the NRM. Let me know if you want the catalogue numbers.

I think you will find that horse shunting was always done from the six foot i.e. the horse was not expected to walk over sleepers. There was a loop or cleat on the solebar of most wagons were the towing line was attached.

Yep. As far as propelling is concerned tension locks and Sprat & Winkles ate effectively very similar. Both use a single smooth point of contact on the wagon's centre line. I disagree. I think the main reason that there are derailments while propelling is that there can be too much friction between buffer faces and that lead them to jamb together and if the track is not perfectly level can leave the wagon 'hanging'. This is probably less of a problem were the buffet are plastic, but steel buffer heads seem to be prone to this. I believe that something similar happened on full-sized stock since I remember that many wagon appeared to have a patch of geese in the centre of each buffer.

Most American, and many European, locos had equalisation beams between springs. They were usually arranged so that there was a three point suspension. As far I know the only (relatively modern) locos that were entirely unsprung were some Aveling and Porters which were based on traction engines.

No great mystery there if you use tension lock couplings.

In this case the cradle holding the leading two driving axles seems to be free floating.

Yep, TINA rules.....

No one needs any sort of model railway. However given that you have underperforming loco, and now a relatively simple solution, you may want to modify this model in the way suggested; as a challenge, because it will teach you new things, or just out of curiosity.

Spring assisted -- as in the early Alan Gibson plastic hornguides.

The trouble with practical experience is that is only as good as a person's understanding. For instance for most people their experience will tell them the best use of a hammer is to knock nails into wood, but some more knowledgeable people will know that hammers are just what is needed to make teapots.

It is easy to see what what is happening. The 'compensation' is transferring weight from the two leading driving axles to the bogie, hence no traction. As of a solution, I would suggest you try something like this: A 'T' shaped beam is put in above the present crossbeam so as to support the centre of the crossbeam. This will produce a three point suspension and should then even up the weights on the driving axles and give much better traction. There are a few thing you should think about with this arrangement. The new beam is going to take 2/3 the adhesive weight of the loco so it may be a good idea to use bolts or pins as well as solder to fix it to the frame. If you were to replace the pointed dropper I've drawn, with a nut and screw you will be able to adjust he height of the crossbeam and the amount of weight it carries. Three point suspensions like this one are sensitive to the position of the centre gravity. If it is too close to the forward suspension point the loco can become unstable. This is likely to be a particular problem with bulleid pacifies as there will be lots of empty inside to fill with lead. Ideally some weight should be in the firebox so that the centre of gravity ends up slightly behind the centre drivers.

That's a bit of a 'how long is a bit of string' question. I can have a good guess at what is wrong, but think I need some more information to be able to suggest solutions, for instance; What exactly do you mean by 'fully-compensated'? I'm guessing it has one fixed driving axle and the other two linked by a compensating beam, but there are other more complicated arrangements which would need different approaches. How heavy is the loco? What are the compensation beam(s) and cross-shaft supporting them made form? Where is the centre of gravity? just a rough idea of this in relation to the centre driver would be good enough.

Slow running is really a test of the friction in the drive train, and by extension how controllable the loco is. There are some people, myself included, who believe that how a model moves, i.e. accelerates and decelerates is at least as important for realism as the colours the locos are painted.

The same is true of the coupled wheels of ta steam loco, either model or full size. Consider the force between the rail and the lightest loaded wheelset. The maximum force that the wheelset can apply to the rail is given by the weight on the wheelset x the coefficient of static friction. If this maximum force on the wheelset is exceeded, the wheelset slips, and the coefficient of friction changes from static to sliding and the force exerted by the wheelset drops. Since the driving force doesn't change, the difference between the maximum and the new sliding force the wheelset can supply is divided between the other wheelsets. If the force transferred from the slipping wheelset brings the next lightest loaded set above the maximum adhesive force, then that wheelset will slip too. And so on until all the axles are slipping.

Not true. For about 15 years before 2001 the Scalefour Society ran a competition which was aimed at improving the performance of locos (the Deputy Chairman's Cup). Part of this competition tested the drawbar pull as a percentage of the adhesive weight. I found the results for 1997 an these show that the drawbar pull varied between lest 10% to over 25% of the adhesive weight.

Not so. if the the axle weights are within about 15% of each other the loco will slip when the lightest loaded axle slips. In effect the maximum traction occurs just before the lightest loaded axle slips and the maximum traction will be a multiple of of the traction supplied by that axle.

There are good practical reasons for moulding in the cab doors. In particular without the doors there is not very much material above the cut out to give the tank/cab-side/bunker any rigidity even in models were the cab roof is moulded in place.

I've just realised there is a spring on the bogie pin. You should, then, be able to cure the rocking by slackening off the screw on the bogie pivot. With luck if both driving axle are actually on the rails you will get a decent amount of traction.

You could try putting a thin washer, start with say 5thou plasticard, between the bogie and the frames.

Maybe, but I would expect very many more locos would suffer from the same problem. Since the video of the assembly shows both wheel sets being mounted in the same press and people who are having trouble report that both wheel sets are out of gauge it is more likely is that the axles have not been full pushed home into the muffs. The answer, then, is to squeeze the axle ends until they are fully home.

There's a photo of a E&WYUR brake van in the first edition of LNER wagons.