Auto couplings, inexpensive and work.

[bertiedog]

 

For un-coupling, could not be simpler, a rising disk will do it under either dropper. the disk could be brass or plastic.

It is on a rod through the board, with spacing washers under the head to space it as per the original instruction sheet.

The rod could be one eighth steel or brass, Any mechanism can be coupled to it, solenoid. motor or hand. A round head would be best as it needs no alignment, about 1 cm diameter.

Stephen 

 

[robert17649]

This is really interesting. I currently use three link but hands and eyes are making that silly.

 

There is a small but please excuse my ignorance but where on the wagon is the coupling fixed, I get midline but do not quite see where in the front to back orientation,does it go over axles ? Ie between axle and floor and so on ?

 

Thanks

[bertiedog]

The wire is best over the axle, and fixed to the middle. The plate shown was the original way, allowing the tip to be moved backwards and forward a bit to allow for layouts with tight curves, but it can just as easily be a vertical hole in the floor and a wire glued in and bent at right angles to do this.

 

Each piece of stock has to be assessed anyway to find out how long the wire is, so a gauge is best made that slip over the buffers to set the hook at the chosen distant, and then you can find out where to bend the wire and drill the hole, I would say for a bit of strength the glue should be epoxy or thick super glue, with the wire a tight fit.

 

For locos it is easy, just find somewhere underneath the drill the hole and then bend till the spear head is in the correct position. The Peckett took about 5 minutes to do, I have since done a Beattie well tank, and a Midland 1F tank, also a LBSCR 062.

At the least you can just drill into the buffer beam or the underside and bend the wire to get it to your chosen level.

 

Remember the Loco head does not have to move at all.

 

There is no indication of what height the head should be above the track, but I would suggest about 5 mm below the buffer centreline, and no lower than a wagon axle height, I will make some experiments to find the best height. For your own layout it does not matter, just make them the same height.

 

At my suggested height, the top pin acts as a hook for wagons three links to engage on the bottom link or the middle for closer coupling.

 

It is a bit of trial and error to fit them, but easier than a hinged Jackson for instance.

 

Stephen

Edited March 4, 2017 by bertiedog

[bertiedog]

On the wire I have blown the "cheap at all costs budget" and bought a pack of .45mm nickel silver on ebay, 300 mm long x 25.....but that should make about 100 + couplings, 50 wagons etc. for about a fiver. The nickel can be used straight from the pack, and is springier than brass, even after the twisting process.

 

I can think of no way of making the original mount easily, it would need stamping, or etching to make it, or a lot of work on a milling machine. However it could be done on a CNC mill easily, one at a time off a roll of brass strip. This is merely mentioned in passing, in my opinion the wire should just be glued into a hole.

 

The only other thing that you will need is some .5 or near brass sheet , it ca be thinner , to make the little area of filled in brass in the middle of the half spear head. The triangle can be snipped with tin shears from a pre cut strip, or flat sheet.

I would make it bigger on the back edge and file to an exact finish to match a test gauge to ensure that they are all the same. If the metal is thicker tan the wire, just file or grind it thinner, with a good fine file or a motor tool disk ( Dremel type)

 

Has anybody actually used the Sayer Chaplin Couplings, not other related types as I am interested in why they have been disregarded for so long, is there a fatal flaw that I have overlooked? I am discounting bad handling or drops or bending etc., as this could affect any couplings.

 

Previously I thought that over all a Peco Dublo had few flaws, except awkward mounting on other makes etc. but this one seems to ring all the bells.

 

I had wondered if a standard unit would fit the NEM pocket, but they do not flex in the up and down way enough, only sideways. It might be possible to fill the NEM pocket with silicon compound and set the wire into it, the Silicon providing the flex, but this is gilding the lily when less complex ways work fine. Also despite what they say all NEM sockets are standard in height or finish, there's a lot of variation across the makes, like the sagging ones on older Dapol wagons for instance.

 

I should add again this all assumes the wagon are ballasted to a reasonable degree, as there is a side force and an up force as they engage, which must be resisted by the wagon's mass, For instance a Airfix cattle truck is too light, but took about 20 gram of weight to make it work perfectly. Most RTR is heavy enough for instant conversion.

 

Stephen

[robert17649]

The wire is best over the axle, and fixed to the middle. The plate shown was the original way, allowing the tip to be moved backwards and forward a bit to allow for layouts with tight curves, but it can just as easily be a vertil hole in the floor and a wire glued in and bent at right angles to do this.

 

Each piece of stock has to be assessed anyway to find out how long the wire is, so a gauge is best made that slip over the buffers to set the hook at the chosen distant, and then you can find out where to bend the wire and drill the hole, I would say for a bit of strength the glue should be epoxy or thick super glue, with the wire a tight fit.

 

For locos it is easy, just find somewhere underneath the drill the hole and then bend till the spear head is in the correct position. The Peckett took about 5 minutes to do, I have since done a Beattie well tank, and a Midland 1F tank, also a LBSCR 062.

At least you can just drill into the buffer beam or the underside and bend the wire to get it to your chosen level.

 

Remember the Loco head does not have to move at all.

 

There is no indication of what height the head should be above the track, but I would suggest about 5 mm below the buffer centreline, and no lower than a wagon axle height, I will make some experiments to find the best height. For your own layout it does not matter, just make them the same height.

 

At my suggested height, the top pin acts as a hook for wagons three links to engage on the bottom link or the middle for closer coupling.

 

It is a bit of trial and error to fit them, but easier than a hinged Jackson for instance.

 

Stephen

Thanks that's clear and now to the building and testing. I did have one more question but you covered it in your next post.

[Izzy]

Really interesting these couplings, the basic design being applicable for any scale. I am just wondering about trying them in 2mm with the spear heads set downwards and used with magnets for un-coupling.

 

As to height I wonder if setting at coach bogie level would be best, so they could be used with all stock? One aspect I am not certain about though, wouldn't they be slightly offset from the centre line? Otherwise with the heads set at an angle they will pass each other, or am I missing something. The original Sayer etches seem to have the wire offset.

 

A few experiments seem to be the next step, with the gauge of the wire being I think a crucial aspect. Wagon weight will also be key it seems. I'll give it a try anyway.

 

Thanks for starting the thread on them Stephen.

 

Izzy

[bertiedog]

The view shows the end and they are a bit off line by about 2.5 mm or so, not at all critical, they would only fail if bent the other way.

The drawing is not to scale but assumes usual 14m height  buffers.

Yes..... these should work in any gauge, but it would need fine steel wire for the 2mm versions.

 

Those original parts are not etches, Sayers stamped them in a fly press in those days. The rest is wire and the brass insert in the head.

 

Trouble with magnetic operation is both sides are pulled at once, so no uncoupling occurs they remain firmly locked. Any magnet repel or attract would have to be on the single dropper arm, with the half spear heads reversed, and losing the ability to take three link as well. Might be worth researching later on.

 

[bertiedog]

On reflection the dropper wire could be steel to attract with the reversed heads, or a tiny 1mm neodymium magnet could be glued to the brass or nickel dropper, in a tiny loop with epoxy to hold it, and repelled upwards by the solenoid or magnet. They would be far enough apart not to influence each other. Remember only one dropper must rise to get uncoupling, if both rise, they remain firmly locked.

But the massive advantage is that upon slackening the pull, any wagon may be simply picked upwards to release it, the tips move apart. Try that with Hornby!! Even the Jackson will not lift out without a twist.

 

Stephen

[bertiedog]

Coming together with a bit of testing, failures can occur if the stock is too light, the upward pressure of the dropper wire can lift some lighter wagons.

• Plain Airfix wagons and Cambrian kits are too light without ballasting, but this is true for any decent running.
• Most RTR is heavy enough, but benefit from extra ballast weight.
• The ballast needs to be about half an ounce at minimum, more will make things easier.
• I now do not recommend using the brass wire, too stiff unless .4mm at most, nickel or steel is best, you could go down to .2mm with steel.

The front face dimension I have chosen is 4.5mm but less or more will work, it is not critical, but less makes for less reliable auto operation.

The uncoupler works fine, just make sure at rest it is below rail head height, and can rise at least 6mm. Any mechanism moving it is best fitted with limit stops to suit your operation requirements.

 

So a revival by complete accident of a very nice vintage coupling system,, how it got lost is beyond me. I make no claims to have designed or invented this coupling, if it was ever patented by Sayer Chaplin it would have lapsed by now any way.

[bertiedog]

The attachment to the wagon can be as simple as a couple of holes with the ends of the wire bent at right angles and glued in, or the ends made into an eyelet and secured under a single screw, or two screws, use a washer to spread the pressure.

Any method must allow adjustment, or be made to suit the wagon by measurement.

 

 

As you can see the wire is slightly off centre and allows the three link chains to be left in place if you want.

The same applies on the fixed Loco mounting, the screw link can remain in place.

 

Stephen

Edited March 4, 2017 by bertiedog

[bertiedog]

Well, all the basic stock for the layout has been converted, I found enough nickel wire in store to proceed, couple of more awkward locos to fit with the units.

 

First general shunting works well, no issues, although I am using a shunting pole with a wedge to press upwards on the dropper to release. The locos pick up on curves down to my minimum on the industrial line of about 14 inches. I had one miss on such a curve, but reversed off and tried again and it picked up correctly.

 

No stock comes uncoupled on the track however hard you try, the tips remain locked. I have a 10foot long test roller coaster track in 00 and p4 with bumps, hollows, and gauge changes, dating from experiments in the 1970's, and the Sayer remains fully locked without pulling stock off the track etc., as it runs along the test track. The same can be said for most rivals, the Jackson is as good, the main failure over it is the Kadee, which hates uneven track, but this track is grossly uneven! The knuckles can ride up and disconnect over the bumps. The bumps and twists are enough to derail stock with modern Hornby couplers, as they cannot take much twist, they do no uncouple but pull the other stock over enough to derail.

 

Next job is the uncoupler and it is an easy type to build, just a few bits to make it operate within limits. I will spring it downwards s that a pull upwards operates it, the pull from a stainless steel cord will do via a pulley on the underside of the layout.

[bertiedog]

Uncoupler plan, fairly straightforward, pull with cord or steel cable as needed or a point motor or a solenoid.The lot is screwed to a wood backing and screwed and glued to the underside of the boards.

A small pulley can be added to guide the cord, or take it through a bent tube for the same effective operation.

 

 

Stephen

[bertiedog]

The diameter of the top should be about 1cm max it could be smaller down to 5mm or less on straight track, but about 7mm seems a good figure. All that's then visible is a rusty disk in the middle of the track, hardly obtrusive.

 

Stephen

[bertiedog]

I am going to try a reduced size version for 009, it should work OK, but will need the finest steel wire to allow the spear point to deflect. Locos can again remain rigid mounting. It is a question of whether the wire will bend enough if on short runs from a bogie or bogie pivot point that is of concern. Rigid 4 wheelers are not to bad, but the wire might have to be longer to reach the far end underside for securing to the chassis.

Stepping up to 7mm scale would pose no issues, there is space and the heads can remain relatively small.

 

Stephen

[bertiedog]

Finally heard from a user of these Sayer Chaplin couplers, a few years or more older than me! and a bit of the back ground. In the late 1940's there were two of three couplings developed to do away with three link and provide auto pickup of the stock, and auto release, the main one was Peco, in the form Hornby used under license from Mr Pritchard.

 

The Sayer design came from Hamblings, but never made by them, and when Sayer went out of business the coupling stopped being made and vanished. The Jackson was a development of the same ideas, but gained more publicity than the earlier Sayer version. He says there were limited mentions of the Sayer Automatic coupling in the Model Railway news at the time, but little advertising.

 

The big increase in the market after the wartime austerities stopped was RTR, and Sayer seemed to confine the interest to their kit locos and kits for wagons etc.

 

The coupling was supported by Stewart Reidpath ltd, and some of the photos of his locos show the type fitted.

 

Now there were some comments and complaints made about the couplings, but read on..........

 

They were too fragile, but this was against the Peco type, which is near indestructible due to the thick metal stamping.

 

If the Loco had a working one, it tended to vibrate as the loco moved, and might not engage, but the modern locos are better slow runners and controllable when the loco approaches the wagons.

 

If the Loco coupling is mounted stiff this stops the problem, but restricts the auto pickup to much bigger curves or straight track. But this is true of most auto couplers, they do not really like curves.

 

The other complaint was the coupling was a bit expensive and this is entirely relative to the prices then.

 

The other main comment was that stock should not be too light, it must be ballasted, but this has come out already, and is easy to do, albeit at a loss of max haulage capacity. The same applies to three link anyway.

 

I have made a reduced version for 009, but the mountings for the wagons are a bit if a nightmare on bogied stock, but not impossible. 2mm is more practical, just a reduction for the 00 version, but the wire used must be the finest possible to get it to spring. I think the ballasting of the wagons would have to be increased to stop the risk of de-railing as the couplers engage.

 

I am working on converting some Dapol 00 wagons that date from the sagging NEM pocket period of production, and require drastic alteration anyway! The whole NEM pocket is removed with force! and leaves a nice clear underside to mount the wires on to.

I have made a gauge to check the buffer height, that sits on the track, and also sets the coupling the correct minimum distance out from the buffer beam, the bend to make the mount is marked with pan, and simply bent at right angles into pre drilled holes in the centre of the wagon floor, glued in with epoxy glue in tight fitting holes. ( .45mm in .4 holes).

 

I did wonder if the infill in the spear head was needed at all, but if the whole shape is made in wire the tip bumps twice over the wires and risks getting caught and locked in place. If no rear wire is fitted the they couple up. but pull apart too much under tension, looking very slackly coupled. The key part is the metal infill inside the head and the inside face.

 

Back to the workshop to make and fit more couplings today.

 

Stephen

[bertiedog]

The various wires have arrived, and the best seems to be .45mm nickel silver, the brass .4 mm works but needs twisting to harden it and make it springy enough.

 

The only issue in making them is getting a nice sharp arrow head point, the wire has to be folded back leaving a sharp point, or at least as sharp as possible. The wire is best bent around a brake, an edge of metal at lees angle than required, the edge will form the bend if pressed with round tipped pliers on each face as it bends. Once bent to shape the infill brass or nickel plate is soldered into place and the whole thing filed over to remove excess solder.

 

The release dropper has its end formed in a loop and soldered on to the wire. The bottom of the wire should be smoothed over with fine emery paper to remove any trace of burrs.

 

Once fitted the end can be twisted to exactly 45 degrees, and bent to bias it way from exact centre or from missing altogether the other coupling face.

 

That's about it then, more tests to do to see how well they work, but so far no problems at all.

 

Stephen

[bertiedog]

Right, further tests show the limits of the couplers and it hardly affects goods wagons, as 30 where tried without a problem of straining the coupling, ( nickel silver version).

 

However I would not sat these are 100% on passenger stock run at speed with 12 coaches, the load is far more, and the jerks and gradient changes might upset the couplings mountings on the bogies. They do not bend outwards etc., but do pull a bit out of line under the max loading.

 

For a branch line or industrial with small loading and frequent shunting they work fine, but main line at speed might damage them, especially if older heavier coaches to pull.

 

The heavy coach issue could be cured with a doubled up wire on the bottom run of wire, this would strengthen it up a lot, or using a heavier gauge wire, say 0.5mm or 0.6mm.

 

 

Modern Hornby are quite free running and relatively light, so they work, but I tried some Exleys and the coupling bent slightly under full load.

 

So, no problem with wagons, except the usual pushing problems with three link, which might be aided with buffers connected by wires, but this is a bit unsightly. Just pays to shunt lighter loads generally, with more care!!

 

Stephen

[Junctionmad]

I've been very happy with Dinghams autocouplers - they're cheap (£12 for enough to equip 20 vehicles), they're pretty unobtrusive and they fit on the bufferbeam just like the prototype. Auto uncoupling with suitable magnets though they'r also easy to uncouple manually. Only downsides are that they're a little bit fiddly to make and they're single handed.

 

DT

I like the Dinghams. But I do find the loop pivot has a lot of slop and over time this causes issues. It really needs a better bearing face , crimping the pivot tends to cause the loop to bind up.

 

Also I have issues with them on bogies , very hard handle reverse curves, in 00 also there is s lot of slop in the back to back which doesn't help things at all ( at least I'm in 00-SF )

[5050]

Very interesting Stephen.  Could be the answer to my prayers!  I have also bought a Dingham etch which I was going to use on stock for my now aborted Forest of Dean layout on which stock would not have been reversed, the single-endedness therefore not being a problem.  The SC coupling does away with the single-ended situation and, once a jig or two has been made, manufacture would seem to be very simple and rapid.  I may have a go soon and try it out!

[Killian keane]

There was an interesting type of coupling compatible with tension locks, invented by Jonathan Duffett in the June 2005 railway modeller involving bent wire, the drawing is a little incomprehensible though

Edited March 12, 2017 by Killian keane

[bertiedog]

There must be a dozen or so auto couplers around made from wire or etchings, the Sayer just is interesting as it is so simple to make and use.... and very inexpensive indeed.

 

 I tried it on 2mm, and good luck! the wire required would be too fine in my opinion, the 00 one uses .4mm so .2mm would be needed or even thinner in steel. Just about the limit of practicality, it would work with Narrow gauge 009, as the stock is heavier, and TT and related narrow gauge, 00/HO, and any larger size.

The limit with 2mm is the light weight can be lifted by the coupling action. So lots of ballast would be the order of the day.

 

The Pecketts W4 040 are all fitted out now with the fixed versions, and all the brewery layout stock has the auto version. The shunting is easy, but is done at the moment with a pole and a wedge to release the couplings, till a bit more planning of where to add the un-couplers.

 

I have thought of a possible reason they had issues with them in the 1940's and that is third rail, there is no way the un-couplers would work with the rail in the middle, and any deflection downwards as they engage would risk shorting out the wagon to the third rail, via the dropper wire. So they were confined to two rail, I think, or outside third, which was still widely used back then.

 

Peco's coupling for Hornby was specifically designed with three rail use in mind, and Tri-ang did no matter as the wheels and most of the rest of the wagon was plastic, and they used two rail only.

 

Stephen

[bertiedog]

Further version on the Dapol 08 scaled up for 7mm use, shows just about a perfect semi auto coupler for O gauge, so small that it barely shows. The wire thickness issues vanishes, about .5mm in steel works, bends under the contact and the stock is heavy enough to resist lifting etc. The screw links can be left in place as well, the clearances are better than 00.

Same as the three rail in 00, if three rail is used, then the dropper release wire must clear the third rail at all times.

Being so much larger it is easy to just use a slide in wedge to release the couplings, although a slightly beefed up solenoid could of course be used for fixed position uncoupling.

 

Stephen.

[bertiedog]

The couplings are moving into use on a new layout, should be easy as no small radius points or track, so buffer lock should not be troublesome. The stock is being equipped at the moment to be ready for testing out the track etc.

 

Ref     http://www.rmweb.co.uk/community/index.php?/topic/122391-middlechurch-marsh-a-small-light-railway-setting/

Edited May 8, 2017 by bertiedog

[AdeMoore]

On reflection the dropper wire could be steel to attract with the reversed heads, or a tiny 1mm neodymium magnet could be glued to the brass or nickel dropper, in a tiny loop with epoxy to hold it, and repelled upwards by the solenoid or magnet. They would be far enough apart not to influence each other. Remember only one dropper must rise to get uncoupling, if both rise, they remain firmly locked.

But the massive advantage is that upon slackening the pull, any wagon may be simply picked upwards to release it, the tips move apart. Try that with Hornby!! Even the Jackson will not lift out without a twist.

 

Stephen

Just found this Stephen,maybe just what I’m looking for l. The above is what interests me rather than the lift uncoupler. I don’t know if you have done any trials? I think I’m going to have a go, with the hook upside down I reckon a hook height wire on the back of the hook would accommodate the 3 links? Anyway I’ll follow your link in the last post and see what you have done.

Cheers

Ade