Am I going to get problems with this R3 bend ??

[collectors]

I want to run a 2 x R3 bend in parallel & believe normally a single track should have 1175mm centre of track radius. I want to run two tracks at 1075mm & 1275 giving a 200mm gap in between centres of the track. Can you see a problem or should this work.
The reason for asking is this is all on a raised track & wont have too much tolerance. Thanks

 

[idlemarvel]

Is this for a 180° turn? If I understand you correctly you want to stretch an LGB R3 curve 100 mm (4 inches) inwards for the inner track and 100 mm outwards for the outer track. I'm not in a position to test it but that seems a bit much to me. If it was me I would want to try it first with a "dry run". If it doesn't work as an alternative have you thought about a mix of PIKO R3 (922 mm radius) and LGB? Then you would only have to stretch the inner and outer curves by about 25 mm (1 inch).

 

[JimmyB]

As idlemarvel mentions, it depends on the amount of track you wish to run on this parallel course. One or two pieces of track may be doable, much more than that, I don't think will work. please provide more details, a small track plan

 

[collectors]

Is this for a 180° turn? If I understand you correctly you want to stretch an LGB R3 curve 100 mm (4 inches) inwards for the inner track and 100 mm outwards for the outer track. I'm not in a position to test it but that seems a bit much to me. If it was me I would want to try it first with a "dry run". If it doesn't work as an alternative have you thought about a mix of PIKO R3 (922 mm radius) and LGB? Then you would only have to stretch the inner and outer curves by about 25 mm (1 inch).

Hi, i was looking at a 180deg, but could push the layout to 90deg bends with some straight in-between the bends. So more an oblong in shape. The bends would be more rounded, but my drawing tools are limited. lol

 

[Greg Elmassian]

90 degree bends with a straight instead of a smooth curve is clearly worse.

But you asked if you are going to have problems. Who could tell you? No one since we don't know the cars you are pulling, locomotives, truck or body mount couplers, length of train, grades, etc.

So the normal advice is the smoothest, broadest curves you can manage.

that is the best anyone can give you without knowing more... but your original question seems to be "can I tweak an R3 curve a bit wider and another a bit sharper for parallel tracks in a curve"

Yes, you will want to bend the track a bit, you might have to trim the ends a bit to overcome largest joints, but the big question will be track spacing, and for this, you need some data on the overhang of your cars as they go through a curve.

So again, a little more data will help get a good answer.

Greg

 

[JimmyB]

Assuming all the curves are R3, it could work, but you will end up with track distances between the track that are uneven, especially on the bends. Trails on the ground before building your raised tracks would be an advantage, as you can see what it looks like.

 

[idlemarvel]

I can't really tell on your diagram where this proposed double track curve is, but it looks like you have quite a bit of space to play with. Good general advice in post #5.

Another alternative, if you have a fixed geometry in mind you or fixed objects to manoeuvre around, is to consider using flexitrack rather than bending set track out of shape. Bit more faff laying flexitrack compared to set track but you can get the exact shape you want.

 

[dunnyrail]

One of the problems you may encounter trying to mess with LGB geometry is that trains could strike each other if you have them next to each other on and approaching the curves. This is really someting you need to test out first with your stock, an option is to have some lining paper and the track laid out, run your largest overhanging stock round with a pencil on the extreme end to make a mark on the paper on all the curve. Do the same with the other curve to see if there are any conflicts.

 

[Gizzy]

I'm not quite sure what you are doing here but a Top Tip from Gizzy.

LGB R3 curves and Piko R3 curves are not the same!

However a Piko R3 fits nicely inside a LGB R3 for a nice double track curve formation.

If you intend to re-radius curves (or flexi-track) to fit your requirements of 1075 and 1275mm, then I would invest, or beg/borrow/steal a track bender....

 

[collectors]

Sounds like i might have to wait till the weather gets a bit better in the UK & do some layouts on the grass. I would like to use what track & other bits i already have as i am going for single scaffold poles "48.3mm" in the ground at 3 feet apart with a 50mm plastic sleeve, with 24" in the ground & 24" out. Then each pole will have a scaffold T bar at the top where i want to run 2 X 6x1" composite/plastic decking boards for 2 parallel tracks for a lot of the layout. It seems the most cost effective high level track that will last a lot better than timber.
The reason for the Q&A is the bends i am making a jig up on an 8x4 sheet of OBS to bend 50mm/2" plastic waste pipe for the bends. This is done with hot sand poured in the pipe & bent into the jig, then left to cool. Sounds like a bit of experimenting is needed.

 

[GAP]

Sounds like i might have to wait till the weather gets a bit better in the UK & do some layouts on the grass. I would like to use what track & other bits i already have as i am going for single scaffold poles "48.3mm" in the ground at 3 feet apart with a 50mm plastic sleeve, with 24" in the ground & 24" out. Then each pole will have a scaffold T bar at the top where i want to run 2 X 6x1" composite/plastic decking boards for 2 parallel tracks for a lot of the layout. It seems the most cost effective high level track that will last a lot better than timber.
The reason for the Q&A is the bends i am making a jig up on an 8x4 sheet of OBS to bend 50mm/2" plastic waste pipe for the bends. This is done with hot sand poured in the pipe & bent into the jig, then left to cool. Sounds like a bit of experimenting is needed.

View attachment 309283
View attachment 309284

Just an aside for a moment instead of mucking around with bending PVC pipe consider using galvanised electrical cable tray,
It comes in various widths, is easy to work with (can be cut easily with snips or an angle grinder) and will last for years if painted.
If you turn it with the tray part down you can make a wide base.
Its what I did for one of my layouts

3. 30-October 2021 Cane Farm (Nicko's Farm) Line Construction Begins

The line is a single out and back loop at one end with a 'Y' point that will move as the trains run through it. The other end runs into th...

ringbalin-light-railway.blogspot.com

4. 23 December 2021 Cane Farm Loop and Mill Run Construction Finished

The track loop that forms the Farms end and the Mill Run to the mill precinct of the cane farm line has now been laid and tested. The track...

ringbalin-light-railway.blogspot.com

 

[collectors]

Just an aside for a moment instead of mucking around with bending PVC pipe consider using galvanised electrical cable tray,
It comes in various widths, is easy to work with (can be cut easily with snips or an angle grinder) and will last for years if painted.
If you turn it with the tray part down you can make a wide base.
Its what I did for one of my layouts

3. 30-October 2021 Cane Farm (Nicko's Farm) Line Construction Begins

The line is a single out and back loop at one end with a 'Y' point that will move as the trains run through it. The other end runs into th...

ringbalin-light-railway.blogspot.com

4. 23 December 2021 Cane Farm Loop and Mill Run Construction Finished

The track loop that forms the Farms end and the Mill Run to the mill precinct of the cane farm line has now been laid and tested. The track...

ringbalin-light-railway.blogspot.com

Hi., oddly enough i am an electrician & looked into cable tray, but came out more cost effective with composted decking. The other thing with galv tray is there a two types. Internal galv & the more expensive hot dip external. The problem with having to do so many cuts on corners, its hard to rust proof it. I even looked into getting it powder coated, but plastic decking was more cost effective. The drawing is what i am aiming for.
The other advantage that i liked with cable tray, is it could be lined with a garden weed fabric or fine mesh & track ballast to let water through & give a better look to the track.

 

[Greg Elmassian]

I'd agree, too many cuts would almost negate the help from the galvanizing (we call it "hot dip" here to distinguish from what you call "internal")

Any chance you can use flex track and not worry about the exact curvature of the track, make it match your bends?

 

[collectors]

I'd agree, too many cuts would almost negate the help from the galvanizing (we call it "hot dip" here to distinguish from what you call "internal")

Any chance you can use flex track and not worry about the exact curvature of the track, make it match your bends?

A good suggestion was to use LGB R3 for all the larger internal curves & a flexible one to match it. "I'm trying to use up what i have" I also am not so familiar with flexible track & believe some are not so computable as others. IE: We have the UK Peco track & the US Peko that dont match very well. "So I am told". But you & others have suggested flexible & i think going with 50% flexi will do the trick.
I also fitted some scaffold tube together today & its rock solid, & the platform on a single row of poles should be good & solid.

 

[Greg Elmassian]

Ahh... Peco is not Piko.... a common confusion.... Peco from the UK, Piko from Germany and has US stuff too.

I do have a chart that compares the "R" numbers of code 332 track:

G scale Sectional Track

Greg Elmassian web site on large scale trains and garden railroads, cigars, and computers

elmassian.com

Peco is not there since it is not code 332

You might find TrainLine 45 might make a suitable radius. (In the US it is sold by a company called TrainLi)

Greg

 

[dunnyrail]

A good suggestion was to use LGB R3 for all the larger internal curves & a flexible one to match it. "I'm trying to use up what i have" I also am not so familiar with flexible track & believe some are not so computable as others. IE: We have the UK Peco track & the US Peko that dont match very well. "So I am told". But you & others have suggested flexible & i think going with 50% flexi will do the trick.
I also fitted some scaffold tube together today & its rock solid, & the platform on a single row of poles should be good & solid.

PECO can be joined with Piko, KGB and Aristo with special rail joiners. SL912.

Peco G Peco/LGB Rail Joiners - 6 off | Garden Railway Specialists Tel:01844 345158

www.grsuk.com

 

[collectors]

PECO can be joined with Piko, KGB and Aristo with special rail joiners. SL912.

Peco G Peco/LGB Rail Joiners - 6 off | Garden Railway Specialists Tel:01844 345158

www.grsuk.com

Thanks for that. Oddly enough i was looking at their site a while back for some Tenmille flexi track. But to be honest there website/IT person wants shooting for a very confusing pricing on the second-hand stuff. Plus when i phoned up to sort the order, they wanted £60 p&p ?. I said your site says free with orders over £300.00. He started to say your order is very heavy & i put the phone down & spent £1100.00 at Kent Garden Railway instead.

 

[Paul M]

Thanks for that. Oddly enough i was looking at their site a while back for some Tenmille flexi track. But to be honest there website/IT person wants shooting for a very confusing pricing on the second-hand stuff. Plus when i phoned up to sort the order, they wanted £60 p&p ?. I said your site says free with orders over £300.00. He started to say your order is very heavy & i put the phone down & spent £1100.00 at Kent Garden Railway instead.

I must admit to being a bit surprised, I know GRS aren't what you would call budget retailers, but to add postage after saying its free seems a bit strange

 

[Gizzy]

Tenmille is made in Suffolk.

G SCALE - Tenmille

Manufacturer and Supplier of Gauge 1, O Gauge and G Scale Track, rolling stock and accessories.

www.tenmille.com

They've updated their website recently....

 

[dunnyrail]

I really only linked to show the product, probably better had I linked PECO site.