More Aristocraft track geometry

[Eeyore.Boater]

Still no railway, but busy planning.
I was thinking of a double track circuit using Aristocraft 9' and 10' diameter tracks, and needed a double junction. The hope was that with some careful planning that the whole railway could be laid with minimal cutting of track. It seemed sensible to assume that the track centres would be 6" based on the two diameters; but that as usual doesn't seem to be the case.
The first picture shows two 10' dia left hand turnouts and a 19.5 deg diamond in the desired layout. The track centres in this layout are 6 1/2" for both the main and diverging routes, with the two turnouts being offset by about 3/4"

The second picture shows the turnouts in a crossover layout; this time the track centres are 6 13/16"

I realy would like the track centre to remain constant through the junction; so it looks like I'll be investing in some new cutting discs
Has anyone else come across this with Aristocraft track
Steve (Eeyore)

 

[Gizzy]

I've no experience of ART track Steve, but most track makes have geometery issues.

You noted the offset of 3/4 inch with the diamond configuration, and I guess this offset is different with the cross over.

If you could trim the 3/4 inch off the straight road of the diamond, this will correct the offset. But then you will need to trim enough from the diagonal road to get your proposed 6" centres, then re trim the straight road again. You could check this by laying the point over the crossing and lining up both points before you cut the crossing. I reckon you will have to use this crossing as your 'reference'.

All a bit fiddly though....

 

[Eeyore.Boater]

I've no experience of ART track Steve, but most track makes have geometery issues.

You noted the offset of 3/4 inch with the diamond configuration, and I guess this offset is different with the cross over.

If you could trim the 3/4 inch off the straight road of the diamond, this will correct the offset. But then you will need to trim enough from the diagonal road to get your proposed 6" centres, then re trim the straight road again. You could check this by laying the point over the crossing and lining up both points before you cut the crossing. I reckon you will have to use this crossing as your 'reference'.

All a bit fiddly though....

Hi Gizzy
Thanks for that.
Something that I recently discovered is that Aristo straight track is in fact supplied in metric lengths, i.e. "6 inch" is actually 150mm, and so on up the range.
It would be logical for the curves to be metric as well, so perhaps the spacing between the nominal 9 and 10 foot diameter curves is really 165mm (6 1/2"), which would make everything sort of ok.
I still have the issue of the lower turnout in picture one being offset to the right, but it looks ok to trim about 3/4" from the 2" available between the ends of the blades and the fish plates. (Of course a custom built 9 foot dia turnout would also cure it. :thumbdown: )
A interesting point for anyone thinking of buying the 19.5 deg diamond crossing - the lack of metal across the centre makes them quite "floppy". In fact Steve at Back 2 Bay 6 thought it was broken when he opened the box in the shop. Fortunately all was well, it just needs a firm base to mount on.
Steve (Eeyore)

 

[Gizzy]

I've no experience of ART track Steve, but most track makes have geometery issues.

You noted the offset of 3/4 inch with the diamond configuration, and I guess this offset is different with the cross over.

If you could trim the 3/4 inch off the straight road of the diamond, this will correct the offset. But then you will need to trim enough from the diagonal road to get your proposed 6" centres, then re trim the straight road again. You could check this by laying the point over the crossing and lining up both points before you cut the crossing. I reckon you will have to use this crossing as your 'reference'.

All a bit fiddly though....

Hi Gizzy
Thanks for that.
Something that I recently discovered is that Aristo straight track is in fact supplied in metric lengths, i.e. "6 inch" is actually 150mm, and so on up the range.
It would be logical for the curves to be metric as well, so perhaps the spacing between the nominal 9 and 10 foot diameter curves is really 165mm (6 1/2"), which would make everything sort of ok.
I still have the issue of the lower turnout in picture one being offset to the right, but it looks ok to trim about 3/4" from the 2" available between the ends of the blades and the fish plates. (Of course a custom built 9 foot dia turnout would also cure it. :thumbdown: )
A interesting point for anyone thinking of buying the 19.5 deg diamond crossing - the lack of metal across the centre makes them quite "floppy". In fact Steve at Back 2 Bay 6 thought it was broken when he opened the box in the shop. Fortunately all was well, it just needs a firm base to mount on.
Steve (Eeyore)

As ART is mainly made for the US market, I guess they quote 'Imperial' measurements as the Yanks have never gone Metric, where as just about every other country in the world (includes Canada) has. Even the UK is sort of halfway there!

I have an LGB 13000 diamond crossing on my layout, on which I had to trim the longer (diagonal) road so it would fit. The LGB 13000 R1 30 deg is (left) handed, so to use in a right hand configuration doesn't work unless you either cut it down or add in (fiddly/expensive) small pieces of track.

I've also had to cut down the odd straight to fit in gaps. One of the shortest is only just longer than a single sleeper....