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hi, has anyone got a helix in their layout. Any views. I want one 45 cms high, 6 and a half turns. john

 

Have you seen the tread on Model Railway Forum?

My helix is 500mm high and has eight turns in N gauge. Six turns in OO would, I think be higher than you indicate in your post - remember to keep the gradient manageable I.e. 1 in 50

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Not really a DCC question - but don't forget that climbing turns are harder on the loco, making it even more prone to slipping to a stand.

 

1 in 50 would require a banker engine, or very short trains!

 

With only a 45cm rise, you would be lucky to get four turns in!

 

At a quick measure, a loco stands about 9cm above the track bed, add some clearance plus under-structure for the next turn, and you are looking at about 13cm per turn.

DCC sound loco's tend to be slightly lighter than plain DCC, because more of the body-weight is planed away to make room for the bigger chip (and maybe the speaker, in non-tender engines)

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John,

As Steve suggests I don't think you will fit 6 and a half turns in to helix rising 450mm. The maths comes out that you will only have 69mm rise on each turn, that's not enough for the ramp material [say 12mm thick MDF], the track + sleepers [say 5mm] and the clearance for 00 gauge locos/coaches/wagons [say 70mm but please check].

If you take these dimensions each turn rises 87mm. If you want 450mm total rise that works out as 450/87 = 5.2 turns. Now you're not going to want the 0.2, so keeping the half turn the two options are 4.5 turns and 5.5 turns. You can now do the maths backwards and the 70mm clearance becomes 450/4.5 = 100-12-5= 83mm for the 4.5 turns and 450/5.5 = 82-12-5 = 65mm for the 5.5 turns.

Final calc is the diameter; length of track in the helix is pi x dia x no of turns. For a gradient of 1 in 50 you need a track at least 50 x 450 = 22500mm = 22.5 metres! A rough approximation for the value of pi is 22/7.

For 4.5 turns > 22/7 x dia x 4.5 = 22500. This solves as dia = [22500x7]/[22x4.5] = 1590mm

For 5.5 turns > 22/7 x dia x 5.5 = 22500. This solves as dia = [22500x7]/[22x5.5] = 1301mm.

Both pretty big circles. I've rushed the cals so apologies if I've made a mistake, no doubt someone will let us know.

 

2eOdtoeric posted whilst I was typing, he suggests more space needed each turn!

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wtd, yes, they would sound better. john 37 Lover, thank you for that. I want to get from my DCC layout to the shelf that runs the lengh and width of my room, about 4 metres square. To climb to this shelf, i need 45 cms, or 17.5 inches. I emailed theus helix people, and they came back with 6.5 turns. I know zilch about helixes, read steves, great construction on model rail forum. Best price i could get was £222. . What i need to know is diameter of the base, as may have to radically design layout, to get it in. Pity you cant just buy a lift. Were your track calcs for a double track. I dont mind less turns. john
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wtd, yes, they would sound better. john 37 Lover, thank you for that. I want to get from my DCC layout to the shelf that runs the lengh and width of my room, about 4 metres square. To climb to this shelf, i need 45 cms, or 17.5 inches. I emailed theus helix people, and they came back with 6.5 turns. I know zilch about helixes, read steves, great construction on model rail forum. Best price i could get was £222. . What i need to know is diameter of the base, as may have to radically design layout, to get it in. Pity you cant just buy a lift. Were your track calcs for a double track. I dont mind less turns. john

 

Using 2nd/3rd radius curves needs a diameter of about 1100mm while 3rd/4th radius (recommended) would need 1200mm. With a 70mm lift on each turn you'd get, as they said, 6.5 turns but you'd have to use nothing thicker than 6mm MDF or ply.

Oh, and another thing, don't underestimate how much track you will need to fill the helix - it will make your eyes water!

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Steve, 37llover, worked out 22.5 metres, but not sure if thats single or double. Have you a cutting list etc for yours. dont fancy making another one. john

Mmmm, tempted by the challenge. As you know, mine is in N so I have the pattern for that, so if it's in OO I'd have to go back a stage and develop a prototype, work out a materials list and costings - but it's doable if you are serious!

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Steve, 37llover, worked out 22.5 metres, but not sure if thats single or double. Have you a cutting list etc for yours. dont fancy making another one. john

 

22.5m for single track; using Steves figures for 6.5 turns and 1.2m dia I think the single track comes out around 25m. John, if you contacted a specialist manufacturer why don't you ask them the diameter? I would also ask them what headroom above the rail top. Obviously they sell them so the product must be okay, it's just if I was building one I'd want a bit more headroom.

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Steve, 37llover, worked out 22.5 metres, but not sure if thats single or double. Have you a cutting list etc for yours. dont fancy making another one. john

 

 

22.5m for single track; using Steves figures for 6.5 turns and 1.2m dia I think the single track comes out around 25m. John, if you contacted a specialist manufacturer why don't you ask them the diameter? I would also ask them what headroom above the rail top. Obviously they sell them so the product must be okay, it's just if I was building one I'd want a bit more headroom.

 

Increasing the headroom would steepen the gradient. Bear in mind also that a gradient on a curve introduces drag and therefore will limit how much a loco can pull up the grade. The one I built in N has a 50mm rise and I can just get my hand inbetween the levels.

4th radius curves have a track centre diameter of 1156mm by the way.

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Increasing the headroom would steepen the gradient. Bear in mind also that a gradient on a curve introduces drag and therefore will limit how much a loco can pull up the grade. The one I built in N has a 50mm rise and I can just get my hand inbetween the levels. 4th radius curves have a track centre diameter of 1156mm by the way.

Yes, if you kept the same radius but I was thinking more of using a larger diameter with flexi track.

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Increasing the headroom would steepen the gradient. Bear in mind also that a gradient on a curve introduces drag and therefore will limit how much a loco can pull up the grade. The one I built in N has a 50mm rise and I can just get my hand inbetween the levels. 4th radius curves have a track centre diameter of 1156mm by the way.


Yes, if you kept the same radius but I was thinking more of using a larger diameter with flexi track.


That would work but the 'footprint' of the helix would be huge. If you have the space go for it.
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The American modeller Joe Fugate had/has a helix, his original one took up 40% of his total trackage! That is with the large basement so many American modellers are fortunate to have. He re-did it by having a gentle climb on the rest of his layout and ended up with I think from memory a turn and a half.Unless one has a large room a helix will dominate and while a necessary evil for some I would always investigate alternatives such as climb around the room or even some form of lift.

 

Regards, Les

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I have just purchased a helix from Model Railway Solutions. Theirs rise 70mm per turn with a 2% gradient. I have the smaller of the 2, twin-track 2nd and 3rd radius. It is 1100mm in diameter.

 

I am going to build a lower shelf under my layout to extend the running loops and for more storage of trains.

 

I also have some n-gauge running alongside my main tracks and am going to put an n-gauge helix inside the OO gauge one.

 

When it is built and running I will post some photos.

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I have just purchased a helix from Model Railway Solutions. Theirs rise 70mm per turn with a 2% gradient. I have the smaller of the 2, twin-track 2nd and 3rd radius. It is 1100mm in diameter.

 

I am going to build a lower shelf under my layout to extend the running loops and for more storage of trains.

 

I also have some n-gauge running alongside my main tracks and am going to put an n-gauge helix inside the OO gauge one.

 

When it is built and running I will post some photos.

Access may be an issue.

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I have just purchased a helix from Model Railway Solutions. Theirs rise 70mm per turn with a 2% gradient. I have the smaller of the 2, twin-track 2nd and 3rd radius. It is 1100mm in diameter.

 

I am going to build a lower shelf under my layout to extend the running loops and for more storage of trains.

 

I also have some n-gauge running alongside my main tracks and am going to put an n-gauge helix inside the OO gauge one.

 

When it is built and running I will post some photos.

 

Access may be an issue.

No problem, the N lines will come in under the OO lines at the base and leave above at the top.

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Hi John

 

I just googled model railway helix pictures and got this

 

http://www.google.com.cy/search?q=building+a+model+railway+helix&nord=1&biw=1248&bih=935&tbm=isch&tbo=u&source=univ&sa=X&ei=oyNjVLi7FsrdaoS7gvgG&ved=0CDQQsAQ

 

One of the diagrams links to here

 

http://model-railroad-hobbyist.com/node/7361

 

Food for thought in amongst that lot.

 

Rob

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I have just purchased a helix from Model Railway Solutions. Theirs rise 70mm per turn with a 2% gradient. I have the smaller of the 2, twin-track 2nd and 3rd radius. It is 1100mm in diameter.

 

I am going to build a lower shelf under my layout to extend the running loops and for more storage of trains.

 

I also have some n-gauge running alongside my main tracks and am going to put an n-gauge helix inside the OO gauge one.

 

When it is built and running I will post some photos.

I have the MRS helix, the 1200mm version, up and running. I found the figures on their website to be slightly different in reality. Here are some pics./media/tinymce_upload/tlwnn18.jpg/media/tinymce_upload/tlwnn32.jpg/media/tinymce_upload/tlwnn44.jpg

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