Accurascale Deltic's via Rails of Shefield

Not yet, as unfortunately Accurascale have mangled this model by going for the bad old compromise of significantly underscale diameter wheels; and the bogie frames may not be right either, as the axlebox moulding centres are below the underscale wheel centres. It's a classic in the 'spoil the ship for a ha'porth of tar' tradition.

I was on this issue very early after announcement in 2018 to see if Accurascale might consider a solution which offered options of 'no compromise but you need 30" minimum radius in OO and more like five feet in P4', and the necessary compromises for R2 capability: underscale wheels to clear under the body work, and a (user removeable) packing piece to adjust body ride height to correct buffer height with underscale wheels. (For sure the axle box centres would then have been above the underscale wheel axle centres, about the same amount that the model has them below the axle centre, so clearly enough acceptable by Accurascale's standards.) I would have envisaged the model sold in R2 capable form, with an option to buy the correct diameter wheels as spares for DIY installation by the nutters who wanted it right.

I am now waiting for their EE type 3 to see if that has potential for retrofit bogies with scale diameter wheels and correct frames, should these be made available as spares.

boxbrownie said:

...I've got an AS Deltic, it is Nimbus, unfortunately it has gone back for some rectification on a kinematic coupling mechanism which keeps sticking and causes the occasional derailment...

Click to expand...

The fundamental problem is the tension lock coupler that is 'standard' for RTR OO product. It simply doesn't have the capability to work these cammed swinging linkages: what is required is a coupler system that links the NEM pockets as a rigid bar; that then 'works' the mechanisms correctly so that they recentre immediately as the vehicles exit curves. (I have been using the Roco pattern within sets of Bachmann and Hornby coaches with complete satisfaction for over 15 years, and plan to trial magnetic types.)

Of the Hornby diesels which exhibited the same problem - back in the day there were many threads on the subject - I have been able to test both the 30/31 and 50: substituting a Roco pattern coupler for the tension lock produced a reliable result with the coaches buffered up to the loco on straight track, and moved apart proportionally to the curve radius to prevent bufferlocking. I would expect the same to apply to the Accurascale implementation. It will be Accurascale's call whether they suggest a more suitable coupler; that would be the winning plan in my opinion.

boxbrownie said:

...The detail is excellent, but I have had quite a few bits drop off (some during delivery) since receiving it whilst it trundles around. I think AS are on a steep learning curve with detail vs robustness, which I read they have acknowledged...

Click to expand...

It has always been the case that the more refined the detail fit becomes - both in quantity of the really small parts represented, and adherence to scale dimensions - the greater the risk of detached parts. (Only once have I seen a small applied detail piece actually 'in the act' of falling off an OO model, generally they 'disappear' unseen.) This I feel we have to live with, if we want to operate the models. (Current champion, the NRM/Rapido Stirling single, nothing has fallen off - but then it is an occasional runner, and not daily 'belted along' on a heavy load - such as a Doncaster pacific or this diesel replacement would be, on 'my ECML' running timetable services.)

boxbrownie said:

...It looks like a very much better designed tension lock type, nice and neat.

Click to expand...

Certainly looks good, definitely going on my 'one to try out' list.

Although the lifting hook principle is the same, significantly the hook will not lock when engaged and in tension because there is no undercut; essential if the couplers are to 'make' as a rigid connection but still be able to release freely on an uncoupler that lifts the hook. So any installed track uncoupler can only lift when the target couplings are overhead, otherwise the whole train will uncouple. (Note for GWR types, potentially ideal for a slip coach uncoupler, just have to actuate the uncoupler at the right moment!)

What particularly caught my eye was the angled guide on the nearside of the illustration, which should act to correctly align the two coupler heads as they approach, compensating for any small off-centre positioning by the mechanisms. That's pretty essential to make it a reliable autocoupler, something of a deficiency of the Roco type.

Unless I have missed some aspect of this new coupler design, it won't be able to do the Kadee trick of remaining uncoupled while being propelled off the uncoupler. But a simple hand held 'flat paddle on a stick', of the sort long used for both tension lock and hook and loop uncoupling, will work fine when the vehicle to be uncoupled is in the required location.

Babz said:

... the bogies derailing and he also had a fix ...

Click to expand...

The fixes are exactly as for all the many existing models with kinematic coupling cams:
Remove the tension lock coupler; it is totally unsuited to these mechanisms
Either use a HO coupler designed to link the mechanisms by forming a rigid bar. Simple and effective.
Or, modify the cam profile to a smooth curve instead of the peak to make recentering easier. Some loss of the close coupling on straight track, but will work with a good autocoupler such as Kadee which doesn't form a rigid bar.

And always likely with small moulded plastic parts, some may have a little roughness preventing free movement as received. 'Exercise them' before going into service to check they work freely, I bung in a little graphite powder for insurance. My oldest Bachmann and Hornby coaches with these mechanisms are still working perfectly after getting on twenty years in service, initially with Bachmann's 'pipes' rigid link (reformed to proper length) or Keen couplers, now all with the Roco pattern coupler.

Greyvoices said:

...I do like to link my models back to the prototype railway as it adds much to the enjoyment of the hobby...

Click to expand...

And on these coaches each Pullman gangway faceplate has a nicely 'buffed' section at the bottom from repeated contact, just where the centre buffer element of the Pullman faceplate is on the prototype. Is this by design or a happy accident? Looks good whatever.