7mm Dinghams Question

[Jack]

Ladies and Gents,

 

Having sorted out the electrical issues on my Peco Setrack points I have finally given the layout a thorough 'test' (read, play trains for several hours)!

 

The layout runs great and all the stock now traverse the points OK.  However, I have found two issues ...

 

1) I find 3 links, even in 7mm, too fiddly, especially after a lot of use of Kadees in 4mm.

 

2) There is some buffer locking on the tight radius points.

 

I was thus contemplating fitting Dingham couples to solve the first issue.  My question is, will Dinghams be OK on the 40.5" radius of the peco track, or will there still be buffer locking issues?

 

Thanks

[chaz]

1 hour ago, Jack said:

Ladies and Gents,

 

Having sorted out the electrical issues on my Peco Setrack points I have finally given the layout a thorough 'test' (read, play trains for several hours)!

 

The layout runs great and all the stock now traverse the points OK.  However, I have found two issues ...

 

1) I find 3 links, even in 7mm, too fiddly, especially after a lot of use of Kadees in 4mm.

 

2) There is some buffer locking on the tight radius points.

 

I was thus contemplating fitting Dingham couples to solve the first issue.  My question is, will Dinghams be OK on the 40.5" radius of the peco track, or will there still be buffer locking issues?

 

Thanks

 

Dinghams have no buffer action and will not solve the problem of buffer locking if you have one. I have no experience of the Peco Setrack points but I suspect you are going to need a coupling which holds the stock apart - Dinghams will not do this being essentially a loop over a pin.

 

HTH

 

Chaz

[brossard]

After futzing around with Kadees for nigh on 30 years in 4mm/00 I resolved that with my change to 0 gauge I would use prototypical couplings.

 

On my previous, now demolished , layout I had a 4'6" radius curve.  Every wagon I had would traverse this curve being propelled backwards.  It is kind of a minimum requirement.  The exception was my friends 0-4-4T which had buffers locking when propelling around the curve.  The reason for this is the overhanging bunker.

 

Like Chaz I have no experience with Settrack turnouts.

 

As for 3 link being a fiddle, yes they are.  I made a couple of simple tools that I tried at an exhibition and which worked very well indeed:

 

 

A couple of modern high intensity flashlights, with thumbswitch, dowel, steel wire and electrical tape.

 

It does take a bit of practice but makes the job a doddle.

 

There are Kadees for 0 gauge (I have some for coaches that were fitted with buckeyes in life).

 

HTH

 

John

 

 

[MarcD]

We have fitted our stock with dinghams. They just about cope with the set track points. its more about over hang and wheel base  than the couplings. Small 15/16ft long 9ft WB wagons and a loco no bigger than a terrier and you should be fine any thin larger and then your lining up problems. 

 

Marc

[F-UnitMad]

11 minutes ago, Furness Wagon said:

We have fitted our stock with dinghams. They just about cope with the set track points. its more about over hang and wheel base  than the couplings. Small 15/16ft long 9ft WB wagons and a loco no bigger than a terrier and you should be fine any thin larger and then your lining up problems. 

 

Marc

Agree with this. The OP doesn't say exactly what stock he's trying to run through these points, but long locos and stock (longer than 0-6-0 and short 4-wheel) are going to struggle; it's a 'hidden' trap for the unwary, or new-comers to O Scale more used to auto-couplings in the smaller scales.

The 'ideal' minimum radius for most O Scale stuff is 6ft. I don't know if Peco put out any information with their 'set track O' points about this sort of restriction? - but if not, they really ought to.

[Jack]

Thanks all,

 

The 4 wheel wagons (various), 6 wheel milk tank (Dapol) and pill box (Dapol) are all fine.  The problem comes with the locos.

 

I have 3 terriers (sang cheng and Dapol) and they cause the worst problems when running bunker first.  Occasional problems occur with the panniers and jintys.  The Minerva Victory is the biggest loco I have, but that is fine.

 

What I wanted to know was, can the Dinghams be set on the terriers (especially) to prevent the locking when propelling through the points.

[Chris Turnbull]

You could replace the buffer heads with a larger diameter or oval buffers.  This will mean that you have to sacrifice prototype fidelity but is this any worse than fitting automatic couplings?  I am sure I have read that this was a solution used on the prototype to cure a similar problem.

 

Another solution is to solder or glue a length of very thin wire, the finer the better, between the buffer heads and paint it black.  Again not very pretty but it will cure the buffer locking. 

 

Chris Turnbull 

 

[MarcD]

Verdict on running our layout with dinghams. Wish I had not changed from 3 link. Hooks locked when shunting and loops also jammed. Unless they behave tomorrow they will be being removed or modified.

Marc

[Jack]

On 06/10/2019 at 00:01, Furness Wagon said:

Verdict on running our layout with dinghams. Wish I had not changed from 3 link. Hooks locked when shunting and loops also jammed. Unless they behave tomorrow they will be being removed or modified.

Marc

 

The Folkestone show was very interesting, a very good range of 7mm layouts.  I counted 5 using Dinghams and spoke to all the operators ... some thought they were great, others ... err ... didn't!  Everyone seemed to agree they were fiddly to operate.

 

Thanks for all the info everyone.  I'm still undecided, but I'm also in no rush :)

 

[Jack]

On 03/10/2019 at 07:35, Chris Turnbull said:

You could replace the buffer heads with a larger diameter or oval buffers.  This will mean that you have to sacrifice prototype fidelity but is this any worse than fitting automatic couplings?  I am sure I have read that this was a solution used on the prototype to cure a similar problem.

 

Another solution is to solder or glue a length of very thin wire, the finer the better, between the buffer heads and paint it black.  Again not very pretty but it will cure the buffer locking. 

 

Chris Turnbull 

 

 

Thanks Chris.  That thought had crossed my mind, but wouldn't suit some of the 'mainline' style locos, although I did find a picture of a Terrier with enlarged buffers.

 

I have decided to remove the 4 offending crossover Setrack points and replace them with regular 6-footers.  That should deal with the buffer locking.  As for the auto-coupling, I will keep thunking.

[New Haven Neil]

On 02/10/2019 at 23:34, Jack said:

Thanks all,

 

The 4 wheel wagons (various), 6 wheel milk tank (Dapol) and pill box (Dapol) are all fine.  The problem comes with the locos.

 

I have 3 terriers (sang cheng and Dapol) and they cause the worst problems when running bunker first.  Occasional problems occur with the panniers and jintys.  The Minerva Victory is the biggest loco I have, but that is fine.

 

What I wanted to know was, can the Dinghams be set on the terriers (especially) to prevent the locking when propelling through the points.

 

Interesting that your Victory causes issues. I have a Minerva and a Dapol pannier, a Heljan 05 and a Dapol 08, as well, and only the Victory buffer locks on the Setrack points.  Upon investigation I reckon it is due to the length of the overhangs, as compared to the wheelbase.  I fitted Maygib larger headed buffers - fixed.  The much bigger panniers are fine - short overhangs.  

 

I am considering Dinghams, as 3 links are beyond my 60 year old eyes and less than steady hand - trial about to begin.

[Happy Hippo]

I use Dinghams and they are very good, however I would say that this type of coupling is only to automate coupling and uncoupling and is not designed for tight radii.  You only have to look at the head of the loop to realise that any excessive overhang at the end of a vehicle is going to cause problems on a tight curve. 

 

I have found that Dinghams are not keen on lightly sprung buffers as they can cause the couplers to fail to uncouple as the compression allows the loop to ride over the hook when propelling.

 

If you need an auto coupler that will prevent buffer locking, then consider a Spratt and Winkle type which has a bar across the full width of the buffers.  This does prevent buffer locking and due to the greater length of the bar, which is also the 'loop' for the hook on the opposing vehicle does give you a little more leeway on tighter curves. If you do what many modellers do and remove the S&W hook off one end of the vehicle, then that leeway is increased because you do not get the hooks clashing against each other.

 

This then makes the S&W 'handed' like a Dingham so you have to ensure that everything is facing in the correct direction.

 

I think that the best methodology is to by a trial pack of each type and see which suits you best.

 

Apologies for the late input into this, but I am currently in Japan, and have only just picked up on this.

 

Blame my phone for any spelling or grammar errors.

[jcm@gwr]

Another option is Links Autocouplers, I've used these on an Inglenook

that I use for an interactive display at local shows, that the public can

operate (mainly younger modellers), so quite reliable.

[Jack]

Thanks all.

 

next step is to replace some of the setrack points with medium ones, and have another thorough test ... will think more about the couplings then.

[New Haven Neil]

Wouldn't fit in my garage if i did that!

 

Dingham trial pack ordered, and I'll give them a go.

[toplink@()1989))((]

Alex Jackson couplings work well, ask Gorden Gravett. I have used them and they work best if built with a jig and a height setter though they work best with electro magnets.

 

Cheer's, Pete.

[Ray H]

I've just fitted Dingham couplings to a number of wagons that I bought second hand recently.

 

I have yet to use them in anger - the layout's just 9ft long and really a shunting plank.

 

Two of the vans that I purchased have the buffer's centre line about 2mm higher than everything else which makes the couplings a similar amount higher. The solebars of both vans are made of quite thick plastic and don't seem to want to flex enough to extract the wheels with a view to replacing them with something of a slightly smaller diameter.

 

I'm currently thinking of either trying to lengthen the buffer beam slot at the bottom to lower the coupling enough to mate up with the rest of my stock or to cut and re-assemble the coupling so that the hooks (& loop) are 2mm lower than they are now.

 

Other than selling the vans on, does anyone have any other ideas for resolving this issue?

Edited November 8, 2019 by Ray H

[MarcD]

I have got the same problem. So I'm looking at designing so modified hooks.

Marc

[Happy Hippo]

Ray,

 

I'd put those two vans to one side and concentrate on getting the rest of your fleet up and running.

 

The essential thing with fitting the Dinghams is to make sure they are all at the same height and 30 minutes making a height gauge out of plastic card will pay dividends.

 

Once you've sorted out  the main fleet, you can re-address the problem of the buffer heights.

 

Personally if you can't get the wheel sets out, I'd  cut my losses and sell them.

 

 

[Ray H]

1 minute ago, Happy Hippo said:

Ray,

 

Personally if you can't get the wheel sets out, I'd  cut my losses and sell them.

 

 

I am minded that way although I have just told someone that I didn't intend to buy any more stock for the layout! Perhaps I might just do it though if I can find a couple of vans at the right price. On the other hand I might just wait until I've built the half a dozen kits that are as yet unbuilt and see whether I still have room for a couple more vans.

 

That said I'm not totally giving up on the two vans yet. I will try and drop the height of the hoop lower which I'd like to think is all that end requires. I haven't fully thought through the other end but wonder if I could file the top off the hook so that it is low enough for loops on lower wagon to engage with it.

[Happy Hippo]

1 minute ago, Ray H said:

 

I am minded that way although I have just told someone that I didn't intend to buy any more stock for the layout! Perhaps I might just do it though if I can find a couple of vans at the right price. On the other hand I might just wait until I've built the half a dozen kits that are as yet unbuilt and see whether I still have room for a couple more vans.

 

That said I'm not totally giving up on the two vans yet. I will try and drop the height of the hoop lower which I'd like to think is all that end requires. I haven't fully thought through the other end but wonder if I could file the top off the hook so that it is low enough for loops on lower wagon to engage with it.

 

Don't waste your time.

 

The hooks and loops really need to be the same height.

 

I speak with some 'authority' here as I had a couple that didn't quite line up.  this was because I just popped them into the existing coupling hook holes and hoped for the best.

 

The resultant scenes of poor coupling and uncoupling, led me to bent the loops to overcome the height difference as you are suggesting, which again led to more failure.

 

Hence my suggestion about the height gauge, which can also be used to space the hooks the correct distance away from the buffer faces.

 

 

[ossygobbin]

has anybody tried to do this or something similar  in o gauge ?

https://platform1mrc.com/p1mrc/index.php?threads/episode-106-18-the-gormo-3-link-coupling-pt-ii.3057/

 

 

[Ray H]

A colleague called round this morning and mentioned the draw-gear end plates that come with the etch. Nothing ventured, nothing gained.

 

I removed the moulded on end plate from the van end and glued the etched version on in its place such that the bottom of the slot through which the hook passes is now a couple of millimetres lower than it was before.

 

Consequently the plate protruded below the bottom of the van end so rather than leave it like that I added a thin strip of plastic across the full width of the van end. I then painted the lower part of the end - the equivalent of the buffer beam I suppose - plus the added plastic black to disguise the join.

 

 

Unfortunately I didn't have (and still don't have for the unpainted wagon) the matching body colour, hence the black. It isn't perfect, can be seen close-up but I think will solve my problem. Neither van is exceptionally well built so this slight adjustment won't matter (in my view).

 

My colleague also mentioned a home made gauge that he said is in the instructions that come with the couplings when I mentioned the height problem. I can't say that I read every word of the instructions again since he came but the only gauge I saw mentioned was for shaping part of the hooks.

 

However, what I did notice was the comment about rigid fixing the couplings in position rather than using a spring like a ordinary coupling does. I've used springs so far. Life would have been so much easier had I opted to fix the hooks originally. Its certainly something else I shall look at in a bit more detail as I'm hoping to spend a fair bit of time shunting the wagons around over the next few days.

[MarcD]

I have cheated on some of my wagon by fixing a plastic block to the back of the buffer beam. It does level out the couplings on most of the wagons.

Marc

[gerrym]

I have experienced similar problems to all outlined above.  Some of you will have seen my thread ref. Queens Street yard no doubt, when all the stock was first built prior to the layout being constructed I may add! Everything was fitted with three links as I had always done.  However the layout was very compact and with a lighting pelmet and framing it is effectively sitting in a fish tank. To reach in with a hook or probe to fiddle with three links was a step to far so a  search was started for something more "automatic". I settled on Dinghams after talking to various layout operators who were using them but the problem then arose of fitting the magnets etc. I didn't want to start digging up scenics and track to accommodate them so decided to to make them "manual Dinghams" or as I call them Half Dinghams .  I have fitted  a hook without a loop to the front of each item of stock and a hook and loop to the rear of each. this means i have to set each piece of stock on the layout the same way around.  I then uncouple each wagon or loco manually using a probe with a straight length of wire to lift each loop . Back to where I started with three links!!!  It actually works quite well but problems arise with rolling stock of different manufacture with differing buffer beam heights. All my stock is kit built or scratch built and the discrepancies are surprisingly large between makers.  

I have exhibited the layout quite a few times now and seem to have to mess about with the coupling loops with a pair of pliers each time!

 

I am still looking for the ideal coupling system  which as yet does not appear to exist, Dinghams are better than many but are still dependent on being accurately set height wise as are Kadees.

 

Gerrym