0.8mm check rail chairs

[Hayfield]

Derek

Hi, I was talking about the check rail chairs

If we take a step back looking at the reasons for Exactoscale producing their own track system. After Exactoscale demerging from the P4 & S4 group and the death of Bernard, Len Newman designed a track work system funded by Andrew Dukes and took over the Exactoscale brand name

Most of the Exactoscale range (especially the special chairs) were designed for P4 track building for use in the P4 Track Company turnout and crossing kits.

Some products were designed exclusively for 00 and or EM gauges, others were able to be used in all 3 gauges

The check rail chairs were only ever made to P4 gauge standards. 0.64 being standard P4 chairs and 0.8mm being gauge widened

The standard EM gauge check rail gap being 1mm. With 00 gauge it depends on which of the many varying standards the builder, the smallest being 1mm (00SF of DOGA fine) and 1.25 perhaps for the track builder most common

Without modifying the Exactoscale checkrail chairs, the gauge will be narrowed, this could cause running issues on smaller radii 00 gauge turnouts and crossings on the curved exits

I have been reliably taught over the years to set the check rail from the Vee using a check rail gauge, not setting the check rail from the stock rail (if using one of those dual use roller gauges or other types)

I have read an interesting article in a Scale 7 mag where the builder only uses a "mint" gauge (no roller or 3 point gauges used). I assume the mint gauge both automatically has the ability to set the check rail (from the Vee) and gauge widen the stock rail, if required where appropriate. But this is my assumption

I do accept 00 gauge is the odd one out where gauge widening is in built to the tolerances of the wheel specification, and a certain amount of fudging can be tolerated. But be warned fudging does not always work. No doubt there will be those who get away using them as are!!

This is not a criticism, but others should be aware of the potential issues of using this item

 

[Derek]

@Hayfield thanks for the details about how these items originated. With regard to Paul's EM model, I thought 0.8mm was the correct gap for EM check rails. Have I got that wrong then? From what I've seen his stock seems to work OK with it.

Thanks
Derek

 

[Martin Wynne]

@Hayfield thanks for the details about how these items originated. With regard to Paul's EM model, I thought 0.8mm was the correct gap for EM check rails. Have I got that wrong then? From what I've seen his stock seems to work OK with it.

@Derek

Hi Derek,

Yes you have got it wrong.

Standard EM uses 1.0mm for the flangeway gap.

There is a finer standard called EM-SF which uses 0.8mm flangeways, but very few modellers are currently using it (or have even heard of it). It runs EMGS and other kit wheels unmodified at existing back-to-backs. But it won't run RTR wheels widened to EM, as you can do with standard EM.

With 0.8mm flangeways it looks closer to P4 than to standard EM, and passes the visual test of having the flangeway gap narrower than the rail head (0.92mm). But at 18.0mm the track gauge is narrower than both of them. In practice the improved flangeway gap is far more noticeable than the reduced track gauge.

More about EM-SF:

https://85a.uk/templot/club/index.php?threads/em-sf-again.459/

https://www.rmweb.co.uk/topic/13558...-em-standards/?do=findComment&comment=4813194

https://www.rmweb.co.uk/topic/13558...-em-standards/?do=findComment&comment=4819313

cheers,

Martin.

 

[Hayfield]

When I asked Len Newman about the 0.8mm check rail chairs, he replied to me they were a mistake. However this was at a time during one of Lens periods of illness. It was suggested to me they were nearer to P4 gauge widened than anything else

These chairs used as they are hold the rails tightly together in the gauge or either 0,64 mm or 0.8mm

On a 5 sleeper check rail I slide 2 CC (centre check chairs) and a CCR, CC & CCL on to the check rail, I then cut through the 5 unused chairs. Using a check rail gauge, I fit the check rails. I then using an appropriate track gauge to fit the stock rails (which can be slightly gauge widened if necessary). As it happens as the check rails are not a tight fit where they are cut in half the joint visually on 1mm check rail gaps (EM & 00SF) are hardly noticeable. For 00 gauge if you look hard enough you will see a small gap but in my mind it still looks far better than 2 standard chairs being cut up

With the Exactoscale special chairs they are designed for P4 gauge, most are fine but use with care. There are 4mm slide chairs for use in EM & 00 gauges. Use gauges all the time

 

[Hayfield]

This is a very interesting history of the P4/S4 societies, especially for me about the formation and History of Exactoscale and its early owners. I became aware of Exactoscale when it was run/owned by Bernard Weller. I was told initially Len Newman was responsible for quite a lot of the technical work for Bernard's designs. I have an idea Len took over Exactoscale after Bernard's death

http://www.clag.org.uk/protofour-chronology.html

Well worth a read for us oldies

 

[Jim Guthrie]

Well worth a read for us oldies

I do remember the aggro in the late 60s/early 70s after the standards were published in the MRC. I think I remember that one problem was that the standards were not dead scale, but included some adjustments to allow for manufacturing tolerances. The MRSG also scaled their 4mm dimensions up and down for the other scales in the UK but members using other scales did not accept them, hence you got Scale7, etc., which were developed separately. The scale standards in S scale were actually developed by Ian Pusey in 1963/4 and they are exact scale.

Another problem was Studiolith's control of the parts production. I remember that is could be quite easy to get on the wrong side of them and they would not supply parts to you. I remember actually buying parts from their stand at the Glasgow exhibition in the early 70s for Protofour modellers who had fallen foul of them.

But it was their demo track on their exhibition stand which sold me on exact scale standards. I think I remember that it was a length of double track with a crossover, and there were one or two coach bogies to run up and down, and through the pointwork. The smooth running through the crossings persuaded me.

I think Len Newman was involved in almost every injection moulded track system in the UK. It was his work which developed the original C&L chairs which, if I remember correctly, came out of his K&L model brickwork system. Then he developed the Exactoscale system. He also developed the chairs for the S scale society and I suspect he probably did work for other societies.

Jim.

 

[Hayfield]

Jim

I think you are spot on about Len designing and or making moulds used by several societies and companies. I think Alan Gibson produced sprues in 4mm scale and sold them within his range. 3 mm society also are made in the same design style. Slaters Plasticard seemingly the only style that differs from the C&L or Exactoscale

Now Phoenix Paints are selling a plastic chair range in 7mm scale under the brand of PermaWay, made by Karlgarin Models, 3 bolt only each sprue contains 16 standard chairs, 2 bridge chairs and 2 slide chairs. Using ABS plastic. Reading the Karlgarin website yet again it states Len Newman was involved (also states in the early days of K&L (forerunner of C&L) Alan Gibson was involved in the early days.

 

[Derek]

I know this is drifting off topic, but given the prevalence of home 3D printing- especially resin- and the amount of chairs and other bits that are already available online to download, either free or for a charge, then not forgetting Martin's incredibly detailed chairs in Templot, are we going to soon see the demise of the plastic chairs from C&L and Exactoscale?

Derek

 

[Daifly]

Unlikely in the short term. The ‘special’ chairs that I have used in 7mm scale are fairly brittle, need to be fixed to wooden sleepers with superglue and are more expensive. Long term, things may be different with, perhaps, more flexible resins and faster printing but that panacea may be some time off.
Dave

 

[Hayfield]

Derek

I think long term you may well be right, however railway modellers are a strange bunch. There is a slow and steady shift to finescale track and in my opinion as folk get used to both the ready to run and British Finescale kits the demand for sizes not produced will grow and scratch and kit building will slowly grow as more either migrate to wider gauges or just want better looking track

Longer term 3D printing I guess is the next step, but until software develops and either 3D printers become as common as paper printers or 3D bespoke printing services pop up (this will come first in my opinion) **

I think the three biggest drawbacks of building trackwork is:-
Tuition
Accessibility (to stock)
Cost

These have to be overcome

** 20 plus years ago my golfing partner was a jeweller, he like many started designing jewellery using cad programs, had the designs printed in wax then cast in which ever precious material was required, he became fed up with the high costs the printers charged.

I remember him buying his own 3D wax printer, cost him over £20.000 and print runs took well over 12 hours to run. He hoped it would pay for itself in 2-3 years. He made it known to his friends that he had space on the printing plate when doing his own printing runs and soon was printing wax masters for his friends. The machine was paid off in under 12 months.

As soon as there is a market someone will fill it

 

[Hayfield]

Unlikely in the short term. The ‘special’ chairs that I have used in 7mm scale are fairly brittle, need to be fixed to wooden sleepers with superglue and are more expensive. Long term, things may be different with, perhaps, more flexible resins and faster printing but that panacea may be some time off.
Dave

Daifly

I have some 3D printed 7mm chairs but at the moment not used them. In 4mm the ABS chairs are very robust, the Check rail chairs are the ones at most risk but in 4mm scale they stand up well, no reason that in 7mm will be the same, perhaps changing from resin to PLA would be better

 

[Daifly]

I have several broken printed checkrail chairs! I would guess that about 15% give up the ghost when threading or adjusting. They are these: https://www.shapeways.com/product/Y...mm-twin-pack?optionId=40817078&li=marketplace

They have a pair of handed flared end chairs plus three intermediate chairs in a 'set'. Threading the five chairs onto the shaped checkrail then requires all 5 chairs to be threaded on to the stock rail together, keeping the flared chairs in position to avoid setting up extra stresses - not always successfully in my case! They look good and even the broken ones can be bodged with superglue when finally in position. Good luck with yours.

Dave

 

[Hayfield]

Dave

What material are you using ?

 

[Daifly]

Material for what? Sleepers are ply or walnut. Chairs are ABS or Shapeways ‘plastic’.

Dave

 

[Hayfield]

Dave

I found the material Shapeways used was a bit brittle, Exactoscale seem more robust

 

[Daifly]

Exactoscale don’t make 7mm checkrail chairs! At least the Shapeways ones are ScaleSeven!