Scratchbuild - Stubby's Mystery Loco is..... The Fell !

[AndyID]

But will this work or will having the g/box's facing different ways cause one end to go forward and the other

to go in reverse , or do the worms work in both directions ?

 

 Yes I know that they do , but that is when you reverse the motor , here we have a common shaft rotation

but g/box's facing two ways .

 

 In other words , are there left and right leading worms or are they all straight ahead ?

 

Or am I just confusing myself . 

 

 It certainly would be a neat and effective solution though .

As long as the worms have the same "hand" and there are the same number of gears in both boxes, the boxes can face in either direction.

[Andy Reichert]

Anyone mentioned Jetex yet?

 

ANdy

[uax6]

 Sorry , but I think that is a bit harsh , Stu has already said he has NO experience of loco building

so he is looking at a simple beginners way , I would and to some extent still do even though I've

built several kits .

It may seem a tad harsh BUT I have only just started to build (well bodge really) kit locos and the odd attempt at modifying rtr to other types, and have found that whereas I was quite happy with the floppy 'toy' style bogies in the past, I have discovered the steering effect that mounting the bogies with some level of side control makes the locos behave in a much more realistic way. Gone is the bogie taking the curve, but the buffer beam going striaght on!

 

It doesn't take that much more effort to do something about it, but the results are well worth it.

 

It doesn't have to be difficult either. Use the loops like Ben Alder uses here on toy bogies http://www.rmweb.co.uk/community/index.php?/blog/62/entry-3478-kyleskus-black-fives/

 

or if you mount a pin on the chassis and put a slot on the top of the bogie, you can control side play with a bit of 0.45mm handrail wire mounted in two holes. Drill one hole on the chassis centre-line as tight against the pivot as you can, and a corresponding hole in the same place on the bogie. The wire should be tight in the top hole, but the bogie hole could be a bit bigger. The bogie will go up and down on the pivot and wire, and will still turn freely. But when the bogie goes into a curve and tries to push out sideways, the wire will act as a spring and will allow the bogie to go over in its slot, but will also be trying to resist this action so always trying to pull the bogie back in line with the chassis centre-line. This will give the steering action.

 

Andy G

[cctransuk]

Hi stubby

 

Having seen John's idea for motorising it as a 4-4+4-4 where he was concerned about the linkage in the fly wheel, how about mounting the second gear box on the thrid axle and doing away with the fly wheel.

 

fell drive 3.png

 

Clive,

 

I did consider this, but felt that a 'brute' such as this needed the inertia provided by a flywheel - and a big one at that !!

 

If the spliced shafts within the flywheel don't run true I might have to consider your arrangement. However, I do have a Unimat lathe so, if necessary, I could turn up a flywheel and ream it to be a precise fit on the two shafts.

 

Of course, I'll not find out until the kit is forthcoming.

 

I can see that this model has at least as much experimental potential as the prototype - so long as it doesn't end up in flames as did the original !!

 

Regards,

John Isherwood.

[Horsetan]

Anyone mentioned Jetex yet?

 

The exhaust back box will be bigger than the model!!

[cctransuk]

Anyone mentioned Jetex yet?

 

ANdy

 

 

Now don't start me on Jetex !

 

Suffice to say that the results, back in the 1960s, when we attached one to a balsa glider, were spectacular to say the least. We never did find it again !!

 

Regards,

John Isherwood.

[PhilJ W]

Now don't start me on Jetex !

 

Suffice to say that the results, back in the 1960s, when we attached one to a balsa glider, were spectacular to say the least. We never did find it again !!

 

Regards,

John Isherwood.

I did a similar thing in my 'yoof', its surprising how flammable balsa/tissue/dope is.

[Horsetan]

If it's going to be a rigid chassis, why not have spur gears linking all axles, Ringfield-style.

It occurs to me that you could also mount the motor transversely with a spur geartrain.

[uax6]

It occurs to me that you could also mount the motor transversely with a spur geartrain.

Which would allow it to be pulled when it fails....... ;-}

 

Andy G

[Stubby47]

Thanks to one and all for suggestions as to how I might motorise this loco.

 

Back in post #47 (spooky, eh) I posted this.

 

 

I've been having a think.....

According to Michael's excellent drawing ( and there seems to be an army of closet Fell admirers going by the high number of downloads !), the centre wheelbase works out at about 25.9mm.

So, if I used a 26mm pre-built motor unit to drive the centre pair of wheels, then the coupling rods would drive the outer wheels and all would be kept in alignment.

The wheels need to be 17.3mm diameter, with extended shafts to drive the cranks and rods.

Does any of that make sense ?

 

 

It still seems to me to be the easiest solution, especially as this is a 'fun' project for the challenge, rather than a (very) serious attempt at an accurate model.

 

So, to elaborate, this is what I think will work.

 

A simple pre-built, powered unit, the correct distance apart, driving both sets of coupled wheels, with the option to add the middle connecting rod.

 

 

 

 

[Clive Mortimore]

Hi Stu

 

Bullant power bogie, they can do a 26mm wheelbase, 16mm wheels (the largest they do) with extended axles. http://www.hollywoodfoundry.com/shopdisplayproducts.asp?id=10&cat=BullAnt+Drive+Mechanisms#

[sp1]

You do realise that once the paint starts to dry on this the H@rnby or B@chmann will announce one, it being a popular topic of discussion on RMWeb.........

[cctransuk]

You do realise that once the paint starts to dry on this the H@rnby or B@chmann will announce one, it being a popular topic of discussion on RMWeb.........

 

No chance - the weird and one-offs are the sole preserve of Heljan !!

 

.... and whilst they're at it - 10800 (though I've already built Dave Alexander's kit version), 11001 (not really - I've got Mike's kit), 18000, 18100 / E1000 / E2001 and 20001-3.

 

Regards,

John Isherwood.

[pete_mcfarlane]

Hi Stu

 

Bullant power bogie, they can do a 26mm wheelbase, 16mm wheels (the largest they do) with extended axles. http://www.hollywoodfoundry.com/shopdisplayproducts.asp?id=10&cat=BullAnt+Drive+Mechanisms#

They do an 8 wheel option as well. 

[Horsetan]

No chance - the weird and one-offs are the sole preserve of Heljan !!....

For now.

 

Although Hornby have produced one or two one-offs in their time....

[Michael Edge]

I've been having a think.....

 

According to Michael's excellent drawing ( and there seems to be an army of closet Fell admirers going by the high number of downloads !), the centre wheelbase works out at about 25.9mm.

 

So, if I used a 26mm pre-built motor unit to drive the centre pair of wheels, then the coupling rods would drive the outer wheels and all would be kept in alignment.

 

The wheels need to be 17.3mm diameter, with extended shafts to drive the cranks and rods.

 

Does any of that make sense ?

Wheelbase is 26mm, wheels are 17mm diameter so all that makes perfect sense

[Michael Edge]

To bring together a few answers, the cranks stayed exactly in sync, no slip was possible, the differentials in the drive were from the four main engines. I was talking to Adrian Ford at the weekend, he worked at Derby at this time although not on the Fell, he thought there wasn't a toilet in this loco.

Any of the suggested arrangements, Stubby's or Clive's will work - it's just two four coupled mechanisms. Eccentric rod arrangements will not work and gear coupling with coupling rods as well causes the same problems in a model as it did in the full size loco - one or the other but not both together.

Bogie swing is no problem - there are no cylinders above these bogies which are as you say standard BR ones. My own model has no sideplay in the driving axles and runs easily round my 28" radius test track.

[AndyID]

I wonder why they originally designed it with gears and coupling rods between the two inner axles? There was probably concern about all that torque ending up at one gear and stripping it. The coupling roads were likely an attempt to ensure that would not happen. Unfortunately, it also created a new set of problems.

 

Despite the fact that the thing was a flop, it's actually a very clever concept.

[Horsetan]

...Despite the fact that the thing was a flop, it's actually a very clever concept.

 

In today's Internet age, they would have called it "The Fail" rather than "The Fell".

[Stubby47]

In today's Internet age, they would have called it "The Fail" rather than "The Fell".

 

It would be a hybrid, using LPG for the auxiliary engines and an electric motor rather than a supercharger.

 

And have an app for twitface....

[Michael Edge]

It wasn't a flop, it worked well for quite a long time but it was a very complicated and expensive way to provide high power in a single unit. It was the most powerful single unit until the first Deltic appeared in 1955.

[chris p bacon]

It wasn't a flop, it worked well for quite a long time but it was a very complicated and expensive way to provide high power in a single unit. It was the most powerful single unit until the first Deltic appeared in 1955.

And when that happened all others became insignificant.

[pete_mcfarlane]

I found this photo of the dreaded Fell whilst looking for something else. Post fire and part dismantled, it's lurking behind 10800 at Derby.

[Neil]

... gear coupling with coupling rods as well causes the same problems in a model as it did in the full size loco - one or the other but not both together.

 

 

 

A good number of n gauge steam engines use a train of spur gears to couple the driven axles which are then dressed up with coupling rods. They seem to perform just as well as those solely rod coupled.

 

[macgeordie]

In the light of the debate around producing a model of 10100, and in the hope that it will stimulate the production of Mike's kit, I reproduce below the drive arrangements that I developed for the A1 Models kit.

 

DRIVE ARRANGEMENTS - MH-1630.JPG

 

The motor is a Mashima 1620 and the gearboxes are High Level.

 

The main flaw in the design, IMHO, is the use of the flywheel as a splice between the motor shaft anf the drive shaft of the RH gearbox. This may well result in the whole caboodle shaking itself to bits - but then that might be prototypical too !!

 

The green outlines are the A1 etchings, and a quick study of the area around the cab windows will indicate why I didn't proceed using that kit !!

 

Regards,

John Isherwood.

Hi John

 

I've just stumbled over this thread, I made one of the A1 models kits about 11 or 12 years ago. I was designed by Rod Neep back in the 1980's and was about the only thing available if you wanted to build one. 

 

The drive arrangement I used was similar to the one you are suggesting.

 

 

It's not brilliant but it works.

 

 

I saw Mike's post and his beautiful drawing, which I assume means he was planning a kit at some stage. Is this still work in progress or has it died a death do you know? In view of the poor take up of many of the Heljan models for the early diesels, they might be reluctant to have a go at this one as the field of operation was relatively small.

 

Ian