Topics

Wiring a Helix for DCC

Brian Eiland
 

You are correct, my is the clear silicon wall sealer and came in a 5 gal can. But the top of the can is rusty and partially open, so I just may not use it. My contractor friend says the PVA latex sealer is what they use on drywall, so best use something like that.

Stephen Lamb
 

That sounds like silicon wall sealer you paint on porous masonry and is normally clearan comes in cans. The PVA/latex mix is milky colour and comes in 5litre plastic containers.

Brian Eiland
 



On Sun, Jun 10, 2018 at 10:20 AM, Stephen Lamb via Groups.Io <stephen489@...> wrote:
I'm out in the Scottish West Highlands. The standing joke is that the precipitation exceeds the evaporation !!!! Our ambient humidity is very high. I decided on natural ventilation because its the fast cycle between the peaks and troughs that cause the warping. I habitually coat everything constructed from ply, thin timber or balsa for buildings and structures with a 50/50 PVA mix to seal surfaces. It also adds a lot of stiffness and provides a good surface to sand. The inner plywood walls  and ceiling of the shed were painted a Sky Blue matt emulsion mixed with PVA. Another good substance is the PVA/latex mix that builders use as a concrete waterproofer additive.

I was going to ask about that type of product as i have a few cans of it,...concrete, masonry sealer . One of them is silconized?
Brian
_._,

Charles Brumbelow
 

And then there is this... Charles


On Jun 10, 2018, at 3:49 PM, Charles Brumbelow via Groups.Io <mrb37211@...> wrote:

Speaking of helixes and their wiring...

https://youtu.be/-hPuNFjRTZA

Charles

Stephen Lamb
 

I'm out in the Scottish West Highlands. The standing joke is that the precipitation exceeds the evaporation !!!! Our ambient humidity is very high. I decided on natural ventilation because its the fast cycle between the peaks and troughs that cause the warping. I habitually coat everything constructed from ply, thin timber or balsa for buildings and structures with a 50/50 PVA mix to seal surfaces. It also adds a lot of stiffness and provides a good surface to sand. The inner plywood walls  and ceiling of the shed were painted a Sky Blue matt emulsion mixed with PVA. Another good substance is the PVA/latex mix that builders use as a concrete waterproofer additive.

Charles Brumbelow
 

Speaking of helixes and their wiring...

https://youtu.be/-hPuNFjRTZA

Charles

Harlan Boyce
 

Just use a latex outside house paint. Get a light to medium color. Put a couple of coats and you will be fine

Boyce's iPhone

On Jun 9, 2018, at 5:20 PM, Charles Brumbelow via Groups.Io <mrb37211=yahoo.com@groups.io> wrote:

Has anyone experimented with sealing the roadbed to reduce expansion and contraction? Shellac might be satisfactory and inexpensive.

Charles


Flash Gordon
 

HI Charles,

Interesting idea, but can you still get Shellac. I think that was made out of bug stuff. Everything is so synthetic now.

Google info:

Shellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes (pictured) and dissolved in ethanol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish.

Ed S


On 6/9/2018 6:20 PM, Charles Brumbelow via Groups.Io wrote:
Has anyone experimented with sealing the roadbed to reduce expansion and contraction? Shellac might be satisfactory and inexpensive. 

Charles


Brian Eiland
 

PVA,....basically wood glues we use so often?

I also found this...
http://www.instructables.com/topics/What-is-the-difference-between-PVA-glue-and-Elmers/

On Sat, Jun 9, 2018 at 6:48 PM, John Cahill <johncahill25@...> wrote:
Guess my next layout will be plywood painted with diluted PVA to seal it! We don’t get extremes in temperature but humidity can go from very dry temperate climate to cold wet, and change can be fast. 

Best Regards,
John

On 9 Jun 2018, at 16:15, Dale Gloer <dale.gloer@...> wrote:

John,  the expansion/contraction issue with any kind of wood is mostly related to the humidity of the environment, not so much on temperature.  Plywood should move a lot less than dimension lumber but is not immune to it.  I live in a semi-desert climate with large differences between summer and winter temperatures and therefore large swings in humidity.  My benchwork is all plywood and I still get issues with seasonal expansion and contraction.

Dale Gloer


John Cahill
 

Guess my next layout will be plywood painted with diluted PVA to seal it! We don’t get extremes in temperature but humidity can go from very dry temperate climate to cold wet, and change can be fast. 

Best Regards,
John

On 9 Jun 2018, at 16:15, Dale Gloer <dale.gloer@...> wrote:

John,  the expansion/contraction issue with any kind of wood is mostly related to the humidity of the environment, not so much on temperature.  Plywood should move a lot less than dimension lumber but is not immune to it.  I live in a semi-desert climate with large differences between summer and winter temperatures and therefore large swings in humidity.  My benchwork is all plywood and I still get issues with seasonal expansion and contraction.

Dale Gloer

Charles Brumbelow
 

Has anyone experimented with sealing the roadbed to reduce expansion and contraction? Shellac might be satisfactory and inexpensive.

Charles

Stephen Lamb
 

I sealed all surfaces and edges of the plywood segments with a 50/50 water/PVA mix.and have not experienced any problems with expansion or contraction although the monitored humidity fluctuates between 45% and 84% with temperatures between +5degC and 24degC. The shed  has automatic frost protection that kicks in at +5degC. The inner walls are lined with plywood to inhibit condensation and are constructed with vapour barrier membrane/50mm polystyrene insulation and 50mm air gap as so are the walls and ceiling. There are adjustable slots in the ceiling to provide ventilation.

Dale Gloer
 

John,  the expansion/contraction issue with any kind of wood is mostly related to the humidity of the environment, not so much on temperature.  Plywood should move a lot less than dimension lumber but is not immune to it.  I live in a semi-desert climate with large differences between summer and winter temperatures and therefore large swings in humidity.  My benchwork is all plywood and I still get issues with seasonal expansion and contraction.

Dale Gloer

Stephen Lamb
 

This is how I constructed my helix:-

https://www.youtube.com/watch?v=PueNBxQd8No

The Bus is clipped to the inner edge of each 9.5mm thk board which are cut out in 120deg arcs using a template which also positition holes for the M12 screwed rod stantions. Each length of rail has a soldered tail running from the bus and completed as each level is added.

Vollrath, Don <don.vollrath@...>
 

A good alternate is to use typical slip-joint type rail joiners with a slight gap in the rails to allow for track-bed movement. Firmly anchor the ties on both sides of each rail joint to help prevent any kinking. Then add an electrical feeder to every section of rail not soldered to another rail with an electrical feeder to the power sub-bus to ensure there will never be any discontinuity.

 

DonV  

 

From: w4dccqa@groups.io [mailto:w4dccqa@groups.io] On Behalf Of John Cahill
Sent: Friday, June 08, 2018 8:33 AM
To: w4dccqa@groups.io
Subject: Re: [w4dccqa] Wiring a Helix for DCC

 

I see where Don is coming from and how that would work. I used plywood and it doesn’t move noticeably even with significant temperature changes. 

Best Regards,

John


On 8 Jun 2018, at 13:28, Timothy Holmes <taholmes160@...> wrote:

Im listening to this discussion closely, as I am about to begin construction of a helix

 

TIM

 

On Fri, Jun 8, 2018 at 7:57 AM Brian Eiland <railandsail@...> wrote:

One nail per helix turn sounds like far to little in a helix spiral? Did you perhaps mean one nail per 36" section of track?? .....Even that sounds questionable.

Brian

*************************************

 

 

On Thu, Jun 7, 2018 at 10:17 PM, Don Vollrath <donevol43@...> wrote:

Yes Brian. It is the roadbed that contracts and expands far more so than the metal rail. When the roadbed shrinks and there is no place like a gap at rail joints for the rail to slide into it can force a kink to occur. If you have neatly nailed down flextrack in multiple places the rials will kink and make wave-like curves between the nails. So in a multi-turn helix one might be better off soldering all rail joints but only securing the track with one nail per helix turn. Now you will not notice the change in roadbed dimension as the track, ties and all, will move ever so slightly.

DonV

 

--

Tim 

San Luis and Rio Grande

John Cahill
 

I see where Don is coming from and how that would work. I used plywood and it doesn’t move noticeably even with significant temperature changes. 

Best Regards,
John

On 8 Jun 2018, at 13:28, Timothy Holmes <taholmes160@...> wrote:

Im listening to this discussion closely, as I am about to begin construction of a helix

TIM

On Fri, Jun 8, 2018 at 7:57 AM Brian Eiland <railandsail@...> wrote:
One nail per helix turn sounds like far to little in a helix spiral? Did you perhaps mean one nail per 36" section of track?? .....Even that sounds questionable.
Brian
*************************************


On Thu, Jun 7, 2018 at 10:17 PM, Don Vollrath <donevol43@...> wrote:
Yes Brian. It is the roadbed that contracts and expands far more so than the metal rail. When the roadbed shrinks and there is no place like a gap at rail joints for the rail to slide into it can force a kink to occur. If you have neatly nailed down flextrack in multiple places the rials will kink and make wave-like curves between the nails. So in a multi-turn helix one might be better off soldering all rail joints but only securing the track with one nail per helix turn. Now you will not notice the change in roadbed dimension as the track, ties and all, will move ever so slightly.

DonV

--

Tim 

San Luis and Rio Grande

Dale Gloer
 
Edited

For what it's worth, on my previous layout I had a 4 turn, 2 track helix in HO with a 27 inch radius.  Each turn was split into 2 parts with detection on each part.  I ran the track feeders down the the track bed supports to terminal blocks that connected to current detectors.  This arrangement was absolutely trouble free.  I used 18 gauge wire for all the track feeders from the terminal blocks.  Don't skimp on wire size.

Dale Gloer

Timothy Holmes
 

Im listening to this discussion closely, as I am about to begin construction of a helix

TIM

On Fri, Jun 8, 2018 at 7:57 AM Brian Eiland <railandsail@...> wrote:
One nail per helix turn sounds like far to little in a helix spiral? Did you perhaps mean one nail per 36" section of track?? .....Even that sounds questionable.
Brian
*************************************


On Thu, Jun 7, 2018 at 10:17 PM, Don Vollrath <donevol43@...> wrote:
Yes Brian. It is the roadbed that contracts and expands far more so than the metal rail. When the roadbed shrinks and there is no place like a gap at rail joints for the rail to slide into it can force a kink to occur. If you have neatly nailed down flextrack in multiple places the rials will kink and make wave-like curves between the nails. So in a multi-turn helix one might be better off soldering all rail joints but only securing the track with one nail per helix turn. Now you will not notice the change in roadbed dimension as the track, ties and all, will move ever so slightly.

DonV

--

Tim 

San Luis and Rio Grande

Brian Eiland
 

One nail per helix turn sounds like far to little in a helix spiral? Did you perhaps mean one nail per 36" section of track?? .....Even that sounds questionable.
Brian
*************************************


On Thu, Jun 7, 2018 at 10:17 PM, Don Vollrath <donevol43@...> wrote:
Yes Brian. It is the roadbed that contracts and expands far more so than the metal rail. When the roadbed shrinks and there is no place like a gap at rail joints for the rail to slide into it can force a kink to occur. If you have neatly nailed down flextrack in multiple places the rials will kink and make wave-like curves between the nails. So in a multi-turn helix one might be better off soldering all rail joints but only securing the track with one nail per helix turn. Now you will not notice the change in roadbed dimension as the track, ties and all, will move ever so slightly.

DonV

Don Vollrath
 

Yes Brian. It is the roadbed that contracts and expands far more so than the metal rail. When the roadbed shrinks and there is no place like a gap at rail joints for the rail to slide into it can force a kink to occur. If you have neatly nailed down flextrack in multiple places the rials will kink and make wave-like curves between the nails. So in a multi-turn helix one might be better off soldering all rail joints but only securing the track with one nail per helix turn. Now you will not notice the change in roadbed dimension as the track, ties and all, will move ever so slightly.

DonV