Converting Hornby Collett Non Corridor Stock to P4

david.themulveys
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Joined: Tue Oct 01, 2013 11:44 am

Converting Hornby Collett Non Corridor Stock to P4

Postby david.themulveys » Sun Jan 19, 2020 8:35 pm

Hi everyone! I’ve recently been having a go at converting a number of Hornby Collett Non Corridor coaches to P4 and I thought I’d share my experiences for discussion and comment. I’ve given a blow by blow description in case that’s useful to anyone, old forum hands may wish to skim every other page… Much of what I’ve written should apply to any recent Hornby coach not just GWR as they all seem to have a similar approach to bogie mountings. As it would make rather a large posting I plan to cover the bogies in this post then couplings and vacuum/steam pipes in a second (thrilling) instalment. Thanks as ever to fellow members of the Farnham MRC P4 group for their encouragement.

First step was to read everything on the Forum about the similar Collett corridor stock (see especially “Hornby Collet Coaches” and “New Hornby Collet Coaches”). One point made by Philip Hall and “Re6/6” is that you may well not need to make any special arrangements at all for suspension in terms of compensation or springing, and instead just rely on the slack built into the bogie pivots by Hornby. I found that this was fine for reasonable trackwork, but in our club the P4 test track has one or two dodgy bits (ideal as a test in fact!) which led to derailments.

001_HornbyGWR7ft_bogie.JPG
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So, the options were either (a) to replace the bogies with one of the various excellent sprung or compensated bogie kits which use cosmetic sideframes or (b) attempt to devise an alternative method. Option (a) is a matter of following the instructions and should result in a good ride, with the slight disadvantage that this approach inevitably increases the width of the bogie slightly. The Hornby GWR 7ft bogies looked so enticing, however, that I decided to try and find a method which would have minimal impact on their appearance while improving the track holding.

The aim is to provide a semi-compensated P4 chassis with a reasonable amount of work, using methods that can readily be scaled up to a rake of four coaches or more. One bogie is fitted with a rocker device allowing the bogie to pivot on a transverse axis so that one wheelset can rise higher than the other eg when encountering a stepped baseboard joint. Fitting both bogies with a rocker, however, would mean that the complete chassis would not perform well on track with a twist (one rail higher than the other). How do I know this – a previous experiment with a Bachmann class 25 (which has two rockers) failed and was only resolved by fitting the loco with a Penbits sprung chassis. Back to coaches - I tried fitting the other bogie with a rocker aligned at 90 degrees to the first one ie along the coach but I rapidly found that although the complete chassis was good on twist, this bogie failed the stepped baseboard joint test in the case where there was an equal step in both rails. So, after some head scratching, it was decided to fit this bogie with a ball joint, allowing it to pivot in any horizontal axis.

002_Ball_and_socket.JPG
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This gives a kind of “three point suspension” by decoupling this bogie from roll of the carriage body but using the rocker at the other end to prevent the body wobbling.

The 00 wheelsets are directly replaced by P4 ones (from Alan Gibson); brass pin point bearings are not fitted on the basis that the coaches are not expected to cover a high mileage but could be added if desired (to drill out the sideframes appropriately one would presumably have to get hold of a “Bob Payne’s Wagon Drill” somehow and try that or else make up one’s own tool – any ideas, what do people usually do about this?).

The steps required for the conversion are as follows:
1. Remove the body (push back the glazing lugs at each corner of the vehicle and ease the body away from the chassis, beware of slight resistance from a couple of what appear to be internal clips in the middle)
2. Squeeze together the clips holding each bogie in place and remove the bogie from the chassis
3. The following steps (4-12) apply to both bogies
4. Carefully take out the OO wheelsets and donate them to your local OO group
5. On each bogie, gently but firmly ease out one end of the wire bracing (linking the W irons on each side of the bogie) from the W-iron

003_Bogie_less_wheelsets.JPG
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6. We can now take out the cross member representing the bolsters by gently inserting a screwdriver underneath
7. In turn, this enables us to remove the brake assembly
8. Remove the clips used to hold the bogie to the body eg by “nibbling” and filing. Clean up to give a hole about 6mm in diameter in the centre of the bogie

004_Bogie_components.JPG
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9. Cut the brake assembly in half longitudinally as per the photo below

005_Split_brake_assembly.JPG
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10. File the brake shoes at 45 degrees to minimise the likelihood of contact with the P4 wheels
11. Glue the half brake assemblies back in (with eg Evostik) so the brake shoes are hard up against the bogie sideframes. Insert the P4 wheelsets and check they rotate freely.
12. Drill the cross member 3mm in the centre and countersink both sides. Glue it back in on top of the brake assemblies. Reinstate the wire bracing.
13. Depending on the choice of coupling (see below), you may wish to fill in the gap at the end of the bogie which Hornby use to accommodate the tension lock coupling and curve adjustment mechanism – pieces of Evergreen 15 x 60 and 40 x 60 can do the trick. Felt no need to fill in complete gap as invisible once bogie is under the coach

006_Reassembled_bogie.JPG
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14. For the bogie at the rocker end, make up a suitable rocker as in the picture below - piece of 8 thou brass 10mm by 10 mm, drill 3mm (eg by starting smaller and enlarging the hole) then solder on eg 0.4mm bearing wires. Glue on top of bogie as shown. Glue an M3 nut into the existing pivot hole at one end of the chassis and secure the bogie with a 3mm countersunk head screw done up loosely (this will allow the bogie to rotate around the rocker as well as pivoting in the usual way on curves).

007_Rocking_plate.JPG
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008_bogie_underside_rocking_end.JPG
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15. For the bogie with the ball joint, obtain a 5mm delrin ball bearing (eg http://www.simplybearings.co.uk or try “loose delrin ball bearings UK” as a search term). Drill it 0.9mm or 1mm, insert 0.9mm or 1mm nickel silver wire and glue in.
16. Add a retaining ring to the bogie frame, cut from a 3mm length of Plastruct 6.4mm outside diameter tube. The ball fits into this and is supported by the countersunk hole we drilled in the chassis cross member.
17. Make up a retaining clip for the ball joint from 8thou brass 10mm by 10mm with phosphor bronze wire eg 28 SWG soldered on, and glue on top of the bogie. You need a small joggle in each leg of the clip to keep it parallel to the horizontal at the ball joint

009_Ball_socket_ and_retaining_clip.JPG
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010_ball_socket_with_ball_unit.JPG
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011_Complete_bogie_ball_end.JPG
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18. Make up a locating bush, to fit into the existing pivot hole at one end of the chassis, to be used to hold the ball in a fixed position a short distance below the chassis. One approach is to mass produce several of these from a bundle of Evergreen strips, with a gap in the middle into which the wire holding the ball fits snugly. Apply MekPak to hold the bundle together and when it’s hardened off, file it to a circular cross section then cut it (recommend use of a mitre block) into a series of 3mm slices to form the bushes. Push the ball unit into the locating bush and glue the bush into the pivot hole on the chassis.

013_Ball_in_place_on_chassis.JPG
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012_Bogie_ball_end_with_SandW_coupling.JPG
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19. You can now clip this bogie in place. Check the whole chassis runs freely including on curved track.
So that’s it for Part 1 – over to you for comment! In Part 2 I’ll cover the vacuum/steam pipes and the couplings.

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Noel
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Noel » Mon Jan 20, 2020 12:41 pm

david.themulveys wrote:The 00 wheelsets are directly replaced by P4 ones (from Alan Gibson); brass pin point bearings are not fitted on the basis that the coaches are not expected to cover a high mileage but could be added if desired (to drill out the sideframes appropriately one would presumably have to get hold of a “Bob Payne’s Wagon Drill” somehow and try that or else make up one’s own tool – any ideas, what do people usually do about this?).


I've never understood the concern that r-t-r manufacturers would use materials likely to wear out in normal use. They can't control how their products are going to be used, which should therefore imply a substantial margin in a design which is in any event intended to use pin-point axles. I don't know, but would not be altogether surprised to be told that the plastics used are less prone to wear than brass would be.
Regards
Noel

Philip Hall
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Philip Hall » Mon Jan 20, 2020 6:29 pm

My feeling is that if carriages happily stay on the track around the layout, and if they only derail on deliberately imperfect test trackwork, there is no need to take on a lot of extra work. After all, trains will be running on a layout where presumably efforts will have been made to correct any really dodgy bits.

I have had converted Hornby carriages running on a big P4 layout, as have friends, and the only modification (on some) has been bearing pads at one end of the vehicle to prevent it rolling from side to side with the other end free to roll around. This is the ‘three point’ system used at Pendon. On the associated test track (which does have some humps and bumps) there were no problems and little to choose between modified and unmodified carriages.

My trains run buffer to buffer with lightly sprung buffers, but I always insist on plenty of weight (minimum of 180 grams) to keep them on the deck and resist buffing and gangway forces.

Philip

david.themulveys
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby david.themulveys » Tue Jan 21, 2020 9:08 am

Noel/Phil

This is very interesting and raises the very practical question of exactly what can we get away with in P4 to save ourselves work.

Our P4 test track is a “roundy-roundy” on baseboards shared with our OO group and consists of ten sections which have to be assembled for each session. The track has been carefully laid with no deliberately introduced “features” but with ten joints there are inevitably issues (which vary from session to session!). In this particular situation improving the ride has been worth it but totally agree, if we can save work that’s the way to go. Interestingly some locomotives are more tolerant of the test track conditions than others; from a somewhat limited sample the Bachmann class 25 was fussy about twist but equally Heljan Hymeks and Bachmann panniers seem to run OK.

If the best view, though, is that given reasonable track the recent Hornby coaches can be converted simply by moving the brakes, adding bearing pads at one end, changing the wheelsets and adding the recommended weight then this is surely very good news which deserves to be more well known especially for beginners. In other words, get yourself some Collett coaches plus a Heljan Hymek or a Bachmann pannier then you’re free to concentrate on track building! [Does this apply to other recent Hornby coaches eg Maunsells, period 3 LMS vehicles, Gresleys? What about slightly older Hornby coaches such as Hawkesworths?].

This of course raises the question of what “reasonable” means. Ideally one would go for something quantitative which could be verified by simple measurements on the baseboard to allow tweaking.

May I suggest the following (I’m assuming that all the P4 standards are fully met in terms of gauge and turnout clearances). At rail joints the maximum step up or down should be x mm, subject to a requirement that the difference in rail height on either side should be no more than x mm. So concretely if x is 0.4 mm then you could have a step up of 0.4mm in both rails or if one had a step down of 0.2mm the other could have a step up of up to 0.2mm. A step up or down of 0.4mm in both rails would mean that as a bogie moved across the joint one wheelset would move up or down relative to the coach chassis by a maximum of 0.4mm (and at the point where the rail joint was in the middle of the bogie one wheelset would be up by 0.2mm and the other down by 0.2mm).

Away from rail joints any dips in the track (caused by eg waves in the baseboard top) or deliberate changes of gradient should be no more than would cause a relative movement of no more than +/- x/2 mm in the wheelsets relative to the solebar on say a 57 foot coach. So one wheelset could move up by this amount with the axle still parallel to the underside of the coach and the other down by the same amount. With a bit of geometry and a little judgement it should be possible to work out the maximum dip (high point to low point) in mm, to make it easier to measure.

Similarly the maximum twist over the same coach length would give a maximum difference in rail height at the coach corners of +/- x mm (so at one end one rail could be up x/2 mm relative to the other, and at the other end the same rail could be down x/2 mm relative to the other).

Most of these could be verified using a flat plate and a bit of brass as a “go-no go” gauge.

Does this seem sensible and if so what should x be for good running with Hornby coaches (and as a supplementary question how large can x get such that sprung bogies can still cope??).

Philip Hall
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Philip Hall » Tue Jan 21, 2020 1:36 pm

David, what you suggest sounds interesting, but I couldn’t comment on precise specifications, because I have never gone to the lengths of measuring track defects, I go by eye. If things don’t look clean and level, then I would rectify it. Of course to put things right entails using a straight edge and square, to see if there is undue cant or the like, but dips and humps I can spot. It would take me far too long to evaluate what defects might cause problems and to what extent that might be. I’m not saying it’s not a useful idea if you feel so inclined, but I don’t feel that way as what I do seems to work. I don’t think I have the time now if I want a working railway of a fair size in a reasonable time frame. I just want to get on with it. Finding the time for that is difficult enough!

I am fortunate in that my railway boards are solidly built and screwed firmly to the walls, so there are no baseboard joints, the surfaces are to all intents and purposes dead level and true, although friends have persuaded me to introduce some slight gradients! The layout I referred to was the Epsom Club’s ‘Wadhurst’ and the club’s test track, a multi gauge affair much like you describe. So all these have baseboard joints, mostly OK but I guess there is the odd one. Yet on none of these have I ever had cause to worry about Hornby coaches with merely the wheels changed. I’ve had a locomotive front bogie catch on a point blade, that sort of thing, but many of my conversions seem to glide along without problems.

So although it’s nice to be able to set some parameters, possibly more so in the context of a club layout where you might want to set limits on what is acceptable, I don’t think it’s essential. The P4 standards should cover most things of course, but suspension is one of those grey areas; you either want to do it or you don’t. Or need to do it or you don’t. And for me, there’s that clock on the wall ticking away.

As for Hornby carriages, they all seem to be built the same way apart from the Railroad range, which are a bit more basic, but even there the same suspension arrangements will apply. The Hawksworth carriages are the same as the Collets you have; highly detailed bogies etc., and the same goes for any of the carriages with very detailed bogies. That’s most of them these days.

Philip

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Noel
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Noel » Tue Jan 21, 2020 3:42 pm

I'm afraid I can't help much, as my main interest is goods traffic. I currently only have two bogie passenger vehicles, a Lima LMS bogie CCT, which came with BR mark 1 bogies :shock:, now on rigid Comet bogies, and an Airfix autocoach on its original bogies. I do have 3 bogie rail wagons [Cambrian kits, rigid bogies] and a Weltrol [Bachmann r-t-r with its original bogies currently - it will get more accurate Rumney sprung bogies one day, but runs OK as is]. I do have several 4-wheel r-t-r vehicles with wheelsets changed but no other non-cosmetic alterations.

My view is try the simplest option first, if it works acceptably well [a very personal judgement] do no more, otherwise look at more complex options.

david.themulveys wrote:Ideally one would go for something quantitative which could be verified by simple measurements on the baseboard to allow tweaking.


How practical this approach is, I'm not sure; I suspect it may be a bit limited. Firstly, as Philip implies, it could be very time consuming, secondly you might well get different answers every time the weather changes. This is not meant facetiously - temperature and humidity changes can easily change what you are measuring in 4mm. In any event, my view would be that your starting point has to be the very best track that you can produce; hopefully then you won't need to quantify track flaws because nothing will fall off :D.
Regards
Noel

davebradwell
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby davebradwell » Tue Jan 21, 2020 6:04 pm

I think you're walking into a conundrum here in that if you can measure your track defects accurately in order to declare it's all in spec then you are probably quite able to lay decent track in the first place.

Track should be as good as you can get it and if you find a step then why not fix it. It's just not as simple as you suggest - some locos have side control, coaches have gangways and need considering with their neighbours, etc. You could be starting on a journey to the bottom with excessive clearances required to cope with larger than life problems. It'll be EM wheels next.

DaveB

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Tim V
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Tim V » Tue Jan 21, 2020 8:47 pm

Of course some of us were using coaches with the wheels changed and no other modifications - and getting reliable running!

On my retired Clutton layout, I just changed the wheels. But I chose to put top quality wheels on, not your ordinary P4 wheelsets. It was that, I am convinced, that resulted in reliable running. I could take an unreliable set of coaches, change the wheels for the better ones - and instantly get better running.

I see that you are using ordinary P4 wheelsets, get hold of some of the top quality ones - and see the difference.
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Philip Hall
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Philip Hall » Tue Jan 21, 2020 9:26 pm

I couldn’t agree more with Tim’s comments about wheels. Truly concentric and wobble free wheels are the first port of call on a voyage to decent running. So often I see vehicles wobbling along when they should be gliding, whether they are suspended or not. People may well be trying to cure a problem with the track when often it’s the wheels.

David, it seems you might live in the South, so if you are able to get to the Southampton show next weekend I will have a few converted coaches with me on my demo table if you’d like to see them.

Philip

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Will L
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Will L » Tue Jan 21, 2020 10:17 pm

The key factor here is always the "rate of change in cant". Where Cant is the difference, at any one point, in the hight of the rail top between our two rails, and the rate of change is expressed as the ratio between the change in cant and the distance over which it occurs. You may get change of cant because of unwanted twist or because of a step in one rail only, but it can also occur naturally if you want to model super elevation or just a change of gradient on a curve.

In the past, when I've been pontificating about the design of sprung suspensions, it has been suggested to me, with some justice, that we should design/build our stock (sprung or not) so they can accommodate a given maximum rate of change in cant. A ratio of 1 in 300 was suggested and I believe the real thing specifies something similar. To ensure vehicles comply, it should not be too difficult to construct a bit of test track with a 1 in 300 slope on one rail only, preferably on a curve. This would show if a vehicle can sit on it with all wheels in contact. To ensure the track complies, it is also possible to construct a 4 wheeled vehicle which is able to measure this ratio and there is such a thing in the Masokits range (item 11:15). I have, of course, done neither, but if one gets serious about this sort of thing...

david.themulveys
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby david.themulveys » Wed Jan 22, 2020 8:20 am

Don't want to interrupt the discussion but yes Phil thanks very much we exhibited there a couple of years ago can't be definite till the day but will aim to be there Sat am

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JackBlack
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby JackBlack » Wed Jan 22, 2020 9:04 am

Tim V wrote:I see that you are using ordinary P4 wheelsets, get hold of some of the top quality ones - and see the difference.


Given that there are limited suppliers of P4 wheels, from whom do I purchase top quality wheels?

davebradwell
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby davebradwell » Wed Jan 22, 2020 9:13 am

1 in 300 is 0.13mm (5 thou') out of flat on a 10ft w/b vehicle; a bogie coach should cope with 0.6 tilt between bogies - so a 10ft vehicle should just about be able to bump over a typical piece of half etched brass. That seems rather too easy but I suspect the test track in question demands significantly more so I suggest your baseboard joints are probably an unreasonable challenge in P4. The 1 in 300 is certainly a number to bring us down to earth. Stock looks awful bumping over steps, anyway - a bit like riding in an Azuma feels.

DaveB

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Tim V
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Tim V » Wed Jan 22, 2020 3:06 pm

JackBlack wrote:
Tim V wrote:I see that you are using ordinary P4 wheelsets, get hold of some of the top quality ones - and see the difference.


Given that there are limited suppliers of P4 wheels, from whom do I purchase top quality wheels?

It used to be Branchlines, but I think it's now moved to another supplier.

They were turned nickel silver wheels, very solid, very round.
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Re6/6
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Re6/6 » Wed Jan 22, 2020 3:35 pm

Brian Osborne at Branchlines still has a supply of 'Black Beetle' wheels from the Australian manufacturer as far as I know.

They're now supplied in stainless steel. As Tim says they're very solid and very round!
John

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Tim V
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Tim V » Wed Jan 22, 2020 3:39 pm

Well that's good to know.

They cost a lot more than ordinary wheels, but the reject rate (I found) was zero, whereas I was lucky to get 50% success rate for the other wheels.
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Re6/6
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Re6/6 » Wed Jan 22, 2020 3:44 pm

Yes they are dearer (£3.80 per axle IIRC) but without 'error' and well worth the extra IMHO.

Also they're now double insulated.

20200122_153901.jpg
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John

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Tim V
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Tim V » Wed Jan 22, 2020 4:05 pm

Re6/6 wrote:Yes they are dearer (£3.80 per axle IIRC) but without 'error' and well worth the extra IMHO.

Also they're now double insulated.

Worth every penny. Pity they are double insulated, the original ones could be used for pickups - for coach lighting for example.

I do remember with the single insulated ones - you had to ensure the wheels were the right way round - otherwise mysterious shorts!
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Re6/6
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Re6/6 » Wed Jan 22, 2020 5:24 pm

Tim V wrote: Worth every penny. Pity they are double insulated, the original ones could be used for pickups - for coach lighting for example.

I do remember with the single insulated ones - you had to ensure the wheels were the right way round - otherwise mysterious shorts!


Indeed Tim, many a cross moment with mystery shorts!
John

Philip Hall
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Philip Hall » Wed Jan 22, 2020 6:00 pm

Last time I bought some I noticed the axles were brass, something to do with Kadee coupling magnet attraction. Just have to be a little more careful with them. They are also just 14mm diameter, which nicely matches the size of Hornby ones.

I am also fond of Ultrascale wheels, having acquired a goodly number a while ago. They are slightly bigger, a scale 3ft 7 1/2 ins, so this means being careful with the brakes, which Hornby mould very close to the treads.

Philip

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Re6/6
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby Re6/6 » Wed Jan 22, 2020 8:45 pm

For information, the disc wheels are additionally available in 8mm, 9.6mm, 10.5mm and 12mm.
John

david.themulveys
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Re: Converting Hornby Collett Non Corridor Stock to P4

Postby david.themulveys » Thu Jan 23, 2020 9:54 pm

Thanks very much for those points everyone nothing like the forum for getting useful tips on how to do things (especially achieving good results with less work!).
As promised earlier, here is Part 2 on Couplings, Vacuum and Steam Pipes

20. Since our club uses Sprat and Winkle (S&W) couplings I opted to use these at the ends (see below) but decided to go for screw couplings within the rake. As these are non-corridor coaches I felt it would be nice to have representations of the vacuum and steam pipes as coupled up (maybe need to get out more?).

21. So, firstly to build the vacuum and steam pipe assemblies. Prototype photos show the vacuum pipe on the left of the coupling and the steam pipe on the right, with the vacuum pipe slightly higher than the underneath of the headstock and the steam pipe slightly lower. To represent this, cut a strip of 100 x 8 thou brass to length (say 24mm) and solder on two lengths of tube (I used Albion Alloys 0.8mm OD 0.6mm ID), one on each side of the strip, each at 4mm from the centre of the strip. File a notch in the underside of the buffer beam to accommodate the vacuum pipe tube and glue the strip in place underneath the buffer beam as shown in the picture below (steam pipe tube can be seen, vacuum pipe tube is underneath on the left).

014_pipe_bracket_unit.JPG
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22. For the pipes I used the tried and tested elastic cord method. Very tempted by the Jim Smith Wright approach using two 1mm neodymium magnets per pipe (see “Working Brake Pipes” MRJ164 p.21) but he reports a concern about how easy it might be to couple up two pairs of pipes and more fundamentally doesn’t recommend it for steel track so in the end opted for a purely mechanical approach. Searching the Web with “1mm elastic cord” aka “1mm bungee cord” yielded a very nice braided tube with elastic inside – several yards long! Other people have suggested “shirring elastic” and Jim suggests jewellers “gimp” wire (any views/experiences?? Have people found “gimp” wire to be flexible enough?).

23. First step is to cut the cord into lengths of about 40mm and carefully remove the elastic to leave just the flexible tube. Having done this, cut the resulting tube into 28mm lengths and superglue 0.4mm brass rod into each end. I also wrapped two turns of 0.2mm tinned copper wire (from low voltage electrical flex) around the pipe to represent the pipe coupling flanges. One of the rods is kept short so it can be lightly glued with Evostik into the relevant mounting bracket, with the other left fairly long so it can be pushed into the opposite mounting bracket and removed again when uncoupling. I found it necessary to insert the pipes with the coaches on their side so the extra length at the free end of the pipe makes it much easier to turn the coaches over and finally push the pipes in after coupling up the screw couplings.

015_vacuum_steam_pipe.JPG
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24. For the screw couplings I used the Masokits version but found it slightly hard to couple these up to the Hornby hook, so for the active coupling I substituted one of the links with a home-made version bent up from 0.4mm copper wire. The other link is the Masokits long type and is located into the slot on the Hornby hook. The inactive coupling can be made up according to the Masokits instructions (I used the short link for both links).

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016_coaches_coupled_together.JPG (16.45 KiB) Viewed 1139 times


25. You now have to decide what couplings you would like at the outer end of the set. Screw couplings - no problem, just clip another couple of couplings off the already depleted Masokits fret. If you would like to use S&W couplings, however, you have a challenge. In the standard form (even using the 3mm version), both the pivot and the paddle would obstruct the bogie preventing it from rotating freely so a modified design is required. The starting point was the same 100 x 8 thou brass strip as used at the inner ends of the set for the vacuum and steam pipes. Cut a 24mm length of this and solder the normal S&W coupling loop (0.4mm brass wire) to it in the usual way.

26. Next cut the paddle off the hook and a drill a new 0.4 mm pivot hole in the hook, with the end rounded off to allow the hook to rotate. Form a suitable right angle bracket from 100 x 8 strip, with another 0.4mm hole to accommodate a pivot pin, and then solder it to the base strip. A Duchesse pin can be used to hold the coupling hook to the bracket – this needs to be soldered into the bracket in such a way as to allow the hook to rotate but as far as possible limit any side movement (time to break out the Rizla papers).

27. The paddle is then trimmed and attached to the coupling hook with a piece of 0.4mm wire bent to allow the paddle to sit between the wheels but not hit anything when the coupling is lowered.

017_Bogie_ball_end_with_SandW_coupling.JPG
017_Bogie_ball_end_with_SandW_coupling.JPG (34.59 KiB) Viewed 1139 times


28. The standard Sprat and Winkle coupling uses three links formed of soft iron wire to form the actuation mechanism. From experience, however, fellow club members have suggested that it may be better to just use one iron link and form the rest from another soft material such as copper. For a coach as opposed to a wagon, however, although this whole arrangement is non prototypical your artistic conscience may suggest use of a representation of a screw coupling rather than using three links. I used a Masokits screw coupling centre/tommy bar with the upper link formed from 0.4mm copper wire and the lower link from 0.4mm iron wire (as supplied for use with the S&W couplings). This arrangement wouldn’t blacken very well but I’ve found Daler’s acrylic ink can give reasonable coverage while being thin enough not to gum up the works.

29. Remove the Hornby tension lock coupling mechanism after unscrewing the retaining bracket. Glue the baseplate of the new coupling onto the lower side of the headstock as shown.

30. Repeat the necessary steps from Part 1 and Part 2 on the other coach(es) in the rake.

31. Form up the full rake, back on a suitable loco, carry out a brake test, set back into the platform, and the next stopping service is ready for boarding!

018_2car_rake.JPG
018_2car_rake.JPG (25.63 KiB) Viewed 1139 times


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