A different type of helix

GAP

GAP

G Scale Model Trains, 1:1 Sugar Cane Trains
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I am thinking of building a helix to make the indoor part my new layout double level and am wondering if the diameters of each level of the helix have to be the same or could I tighten the radii of each level eg start out at 900mm (approx. 3ft) radius and finish with 750mm (approx. 2.5ft) at the top.
The idea is to make scenery of a train climbing the side of mountain (1:20.3 Shay and Connie mostly) which has a slope. It will then run across the back of the shed and down on similar helix on the other side. For the run across the back I want to do scenery between the two levels and really want to have some depth perspective.
Thoughts and suggestions most welcome.
 
GAP said:
I am thinking of building a helix to make the indoor part my new layout double level and am wondering if the diameters of each level of the helix have to be the same or could I tighten the radii of each level eg start out at 900mm (approx. 3ft) radius and finish with 750mm (approx. 2.5ft) at the top.
The idea is to make scenery of a train climbing the side of mountain (1:20.3 Shay and Connie mostly) which has a slope. It will then run across the back of the shed and down on similar helix on the other side. For the run across the back I want to do scenery between the two levels and really want to have some depth perspective.
Thoughts and suggestions most welcome.
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The idea of a smaller diameter at the top seems OK - this would allow you to ease the gradients. As I see it, combined curves and gradients put more strain on the train so anything you can do ameliorate that strain would be a great help. Shorter train would help too.
 
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Have a look at this Vid Gap, will give you some kind of idea about the size you need to climb just enough to get over 1 track.


The inner Radius of this are all R1 the outer at the Top and Bottom Level is at the far end is R2. This took a lot of planning to get right and from memory the Shed it is in is roughly 12 x 8 feet. Boards are secured to make the Gradients using Threaded Bolts Nuts and Washers. This gives you infinate abilities to get the gradients correct. Not sure what gradients were used for this setup, probably in the order of 1:40-50.

Sorry do not do % for Gradients in UK. Totally do not understand % for gradients even though all of our Road Signs have been altered! I just now go very slow whenever I see a Hill Road sign!
 
That's a nice video find there. Not sure how the owner gets into that shed!

Percentage gradients are easy to convert to ratios if you have a better feel for those. Just divide the grade by 100, so 50% grade is 50/100 = 1/2 or 1 in 2 as you would say, 20% is 20/100 = 1/5 or 1 in 5, etc. If you remember your school geometry, they are both ways of expressing the tangent of the angle, opposite (rise) over adjacent (run), ref https://en.wikipedia.org/wiki/Grade_(slope)
 
750mm sounds a bit tight - the principle sounds fine as Mick says, but can you start a bit wider so that you end up at 1200mm radius at the top.

I can't see the Connie doing 750mm :mm::mm::mm::mm: (I don't do anything less than 1200mm radius on my railroad) I may be wrong, but as Mike found out with his puddings, you also get the drawstring effect (and I'm not talking about his wallet :eek::eek: ) on the following rolling stock.
 
Rhinochugger said:
750mm sounds a bit tight - the principle sounds fine as Mick says, but can you start a bit wider so that you end up at 1200mm radius at the top.

I can't see the Connie doing 750mm :mm::mm::mm::mm: (I don't do anything less than 1200mm radius on my railroad) I may be wrong, but as Mike found out with his puddings, you also get the drawstring effect (and I'm not talking about his wallet :eek::eek: ) on the following rolling stock.
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Totally agree about 750mm and Connie I just measured the tightest curve on my current layout and it is 750mm and Connie will not go round it she will go round the 900mm curves OK but I think 1000mm would be the minimum I should be aiming for.

All the others do including my Shay so maybe Connie will be restricted to the outside part of the layout where large curves can be made.

I think I am going to have to build some sort of mock up of this using good old garden stakes and string.
 
GAP said:
Totally agree about 750mm and Connie I just measured the tightest curve on my current layout and it is 750mm and Connie will not go round it she will go round the 900mm curves OK but I think 1000mm would be the minimum I should be aiming for.

All the others do including my Shay so maybe Connie will be restricted to the outside part of the layout where large curves can be made.

I think I am going to have to build some sort of mock up of this using good old garden stakes and string.
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good luck!
 
idlemarvel said:
That's a nice video find there. Not sure how the owner gets into that shed!
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I made the Vid on a visit to the line shortly after the Shed was fitted out with Track. I built the Shed as well for him. The Cross Piece at an Angle is on a short removable section. Track joined by Bridge Track Clamps, one of my better ideas. The door has door hinges with two lifting bridges, held in place when up with magnetic clamps. Track is just again locked into place again with Bridge Clamps.
 
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You are a naughty, naughty lot!!! I should really be very very cross wiv you. You has given me a idea wot I can't even contemplate propper 'til I gets 'ome an' has a measure up! If it were to work out, it could transform the T.V.B.L. and considerably increase it's running length and fun quotient.

Why I had not fort of dis before is a major mystery (p'raps not, I not always clever!). :shake::confused::nod::confused:

AND, If it doesn't work out I could be exceedingly disappointed. :cry::cry::cry:
 
GAP said:
This is a sketch of what I have in mind
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If I am interpreting this correctly, your diagram is all inside a 13 ft deep by 19 ft wide shed?
G-force1 said:
You are a naughty, naughty lot!!! I should really be very very cross wiv you. You has given me a idea wot I can't even contemplate propper 'til I gets 'ome an' has a measure up! If it where to work out, it could transform the T.V.B.L. and considerably increase it's running length and fun quotient.

Why I had not fort of dis before is a major mystery (p'raps not, I not always clever!). :shake::confused::nod::confused:

AND, If it doesn't work out I could be exceedingly disappointed. :cry::cry::cry:
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Yes it's all a cunning conspiracy to get you to spend even more time and money on your hobby :-)
 
'Tis the serious frustration of not being able, from here, to do anything, but visualise, something which is probably impossible/impracticle. :banghead::banghead::banghead::banghead::banghead::banghead::banghead::banghead:
 
G-force1 said:
'Tis the serious frustration of not being able, from here, to do anything, but visualise, something which is probably impossible/impracticle. :banghead::banghead::banghead::banghead::banghead::banghead::banghead::banghead:
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Now come on!

Nothing is impossible.. Given enough time, money, and a big enough hammer!!
:rofl::rofl::rofl:
 
PhilP said:
Now come on!

Nothing is impossible.. Given enough time, money, and a big enough hammer!!
:rofl::rofl::rofl:
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Yer still need enough room t' swing the bugger!

Room is what I have little of.
 
I had a patch of the garden that was just a straggly bush with a dead tree and other 'dead space' behind. I had wanted to get a trestle and a bridge into a part of the line so I had an idea...
I cleared the bush and surveyed the space to get in a 'spiral'.
There was not as much room as I thought. In fact it was going to have to be R1 and maybe a couple of R2 curves.
It would have to take locos like Bachmann Annies, LGB Sumpter Mallet, Bach and Accy climax and shays so the clearance under the bridge would have to be nigh on 10".
I raised the incline approach track that used to actually slope down and dug down to let the spiral fall enough to go under the bridge.
The difficult part was getting the gradient on the curve section to follow a smooth degree of incline.

The curve together with the incline needs extra effort from the locos especially if they are hauling anything. As it is the meandering 'local' line I did not expect to have long heavy trains so I was not too worried.

The Sumpter valley mallet hauls three to four freight cars or two Bachmann/LGB passenger cars.
The Annie will haul one flat car and one Passenger car (a nice local shorty train)
The Climaxes and Shays can haul a few log cars or coal hoppers.
Single things like Geese or other 'rail motors' are fine of course

So the spiral is there and it operates even if the radius is a wee bit cramped making the climb a little harder.

Here are the posts of the spiral build:

https://www.gscalecentral.net/threa...finds-the-lost-land-and-gets-a-spiral.298716/

https://www.gscalecentral.net/threa...d-and-gets-a-spiral.298716/page-2#post-323891

https://www.gscalecentral.net/threa...igh-line-section-is-finally-completed.301551/
 
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