Pre-soldering flex track for curves
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If there is any kind of that track, I have never seen it. I have to remove ties no matter what flex track I've used.
I connect two pieces with flush ends, solder, lay in place, and cut the next end flush and repeat the process. Some like staggered joints, I don't. I want to work both ends side by side. There is not a right or wrong way, it's whatever works for you.
And like Rico said, save those removed ties so you slide them back under the rail. I wish I'd remembered to do that. It's not very noticeable after using a light ballast on concrete sleepers, but a light ballast and wood ties is more noticeable.
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RhB Michael
RhB Lokführer
Are you talking about not using a rail joiner and just soldering the ends together? I don't know anyone who has tried that. Ties usually have to be removed to slide a joiner on the end of the rails, then solder, and then bend into place and secure to the roadbed and sub-roadbed.
If your railroad is in a climate-controlled part of your house I wouldn't worry much about the joint moving about unless the sub-roadbed is not painted or otherwise unsealed, and your house gets unusually dry in winter.
It gets very dry in my home during winter and I have to rig up a makeshift humidifier for one part of my layout to keep the wood from shrinking so much that it buckles the track.
If your railroad is in a climate-controlled part of your house I wouldn't worry much about the joint moving about unless the sub-roadbed is not painted or otherwise unsealed, and your house gets unusually dry in winter.
It gets very dry in my home during winter and I have to rig up a makeshift humidifier for one part of my layout to keep the wood from shrinking so much that it buckles the track.
Toolbelt
Well-Known Member
Yes, using rail joiners. I thought some flex track has modified ends to allow rail joiners without having to remove ties IF installed straight, or has enough rail overhang to fit joiners IF installed straight? My question is more about, in a curve, one rail will shorten or lengthen as it's flexed, but to what degree? Is there a formula based on the radius, as to how many ties to remove? Obviously, the tighter the radius, the greater the slippage of one of the rails.
Rico
BNSF Modeller
If the curve only uses two lengths of flex and the sliding rail is on the inside of the curve the joint should remain pretty much centered. Not all flex has a sliding rail however, like the ME weathered track I used.
In that case I removed one tie from each end and notched a tie to allow the joiner to slide over.
By the way, wherever a tie was removed I sanded a tie so it was thin enough to slide back in place.
In that case I removed one tie from each end and notched a tie to allow the joiner to slide over.
By the way, wherever a tie was removed I sanded a tie so it was thin enough to slide back in place.
santafewillie
Same Ol' Buzzard
Remember to position the sliding rail on the inside radius of the curve. Less ties to remove.
RhB Michael
RhB Lokführer
If there is any kind of that track, I have never seen it. I have to remove ties no matter what flex track I've used.
I connect two pieces with flush ends, solder, lay in place, and cut the next end flush and repeat the process. Some like staggered joints, I don't. I want to work both ends side by side. There is not a right or wrong way, it's whatever works for you.
And like Rico said, save those removed ties so you slide them back under the rail. I wish I'd remembered to do that. It's not very noticeable after using a light ballast on concrete sleepers, but a light ballast and wood ties is more noticeable.
Toolbelt
Well-Known Member
So is a good starting point removing 1-2 ties from each end to be joined? I don't want to remove 2 ties each when I could have gotten away with only 1 removed, or worse, not removing enough and having a joiner snag on a tie.
RhB Michael
RhB Lokführer
You'll have to sort of play it by ear. I don't think I've ever gotten away with removing only one tie. But save the ones you remove so they can be placed under the rails when finished. The joiners and solder will hold the rails in gauge.
Not removing enough is always a problem because the joiner will not allow both pieces to fit together.
Not removing enough is always a problem because the joiner will not allow both pieces to fit together.
santafewillie
Same Ol' Buzzard
Remove one from the two ends that you are joining; then the other end you will have to eyeball.
Michael B
nGuru Train Layouts & Components
I do not remove ties to prevent melting.
Try this...
Flip your track over and remove the webbing between some ties near the joint. Just enough so you can slide them down away from the heat. When you have finished soldering, slide the ties back into position. The joiner will stop you - overcome that by laying your iron on top of the rail just enough to soften the plastic, but not hot enough to unsolder things.
Try this...
Flip your track over and remove the webbing between some ties near the joint. Just enough so you can slide them down away from the heat. When you have finished soldering, slide the ties back into position. The joiner will stop you - overcome that by laying your iron on top of the rail just enough to soften the plastic, but not hot enough to unsolder things.
strobelight
Well-Known Member
I read somewhere about shortening one rail of flex track so that the joints don't line up. Is that a valid thing to do?
diesel
Weedy Liver
Yes, it's called a "staggered join". One flex rail is fixed, the other one slides. If you position the fixed rail of both pieces on the outside and solder those together, you will observe a few things:
1. the position of the outer join is fixed, since both rails are fixed. That also fixes the ties of both track pieces in position.
2. There will be surplus rail on the inside, and since both pieces are sliding, the surplus will appear either:
a) on both ends (if the inside join is exactly in the middle)
b) on one end only (if the inside join is offset from the outside join)
This means you can choose a centered join, or an offset join, and still have sufficient sliding rail on the inside, to reach both ends of the combined piece. It is generally advantageous to use "staggered", or offset joins because there is considerable tension on the rails that wants to make it straighten out. That means, at the join itself, the bending forces don't form a smooth curve. If you use a soldered rail joiner to make the connection, what you really have is an extremely short straight section of rail, that accommodates the bending force of the rails it connects. But the alignment comes from the webbing on the ties, all the forces are constrained by that.
Placing the fixed and sliding joins in the same place, puts the guiding force of the webbing all the the same area of track. So when the track is bent, the discontinuity of the joins will combine. The bending effort exerted by the rails is combined in one area. This increases the effect of the discontinuity of the joins, and places more bending stress on each individual join.
When the fixed and sliding join are offset, it distributes the bending stress to two different areas, thus the stress on each join is cut in half. Secondly, the track to track alignment variation caused by the imperfect bending of the rail at the join, is cut in half since it occurs in two different places. Additionally, it combines the tie section between the two joins, such that it is actually supported by continuous rail sections coming from two different directions. This helps to stabilize the ties.
To make either kind of join, you would make the fixed join, bend the entire assembly inwards to make the target curve, and then align the sliding pieces to where you need them, make any tie cuts that you need, and then make the sliding join. Or, bend it only to confirm the sliding ties will reach both ends, then solder the sliding rail join while the tracks are straight. Then bend and position. Which one of those methods you use, is mostly a matter of personal preference. Soldering while straight has lesser risk of weakening the tie web supports via melting.
You can also place the sliding and fixed rails opposite one another, but it will leave you with missing rail on one end when you bend it.
Related Note: Insulating gaps can be a problem on curves because of the bending tension. Since they can't be soldered, the bending correction force has to be conveyed through the tie webs alone. An insulating joiner usually has very little strength, it's mainly there just to align the track ends. I avoid block section ends on curves.
1. the position of the outer join is fixed, since both rails are fixed. That also fixes the ties of both track pieces in position.
2. There will be surplus rail on the inside, and since both pieces are sliding, the surplus will appear either:
a) on both ends (if the inside join is exactly in the middle)
b) on one end only (if the inside join is offset from the outside join)
This means you can choose a centered join, or an offset join, and still have sufficient sliding rail on the inside, to reach both ends of the combined piece. It is generally advantageous to use "staggered", or offset joins because there is considerable tension on the rails that wants to make it straighten out. That means, at the join itself, the bending forces don't form a smooth curve. If you use a soldered rail joiner to make the connection, what you really have is an extremely short straight section of rail, that accommodates the bending force of the rails it connects. But the alignment comes from the webbing on the ties, all the forces are constrained by that.
Placing the fixed and sliding joins in the same place, puts the guiding force of the webbing all the the same area of track. So when the track is bent, the discontinuity of the joins will combine. The bending effort exerted by the rails is combined in one area. This increases the effect of the discontinuity of the joins, and places more bending stress on each individual join.
When the fixed and sliding join are offset, it distributes the bending stress to two different areas, thus the stress on each join is cut in half. Secondly, the track to track alignment variation caused by the imperfect bending of the rail at the join, is cut in half since it occurs in two different places. Additionally, it combines the tie section between the two joins, such that it is actually supported by continuous rail sections coming from two different directions. This helps to stabilize the ties.
To make either kind of join, you would make the fixed join, bend the entire assembly inwards to make the target curve, and then align the sliding pieces to where you need them, make any tie cuts that you need, and then make the sliding join. Or, bend it only to confirm the sliding ties will reach both ends, then solder the sliding rail join while the tracks are straight. Then bend and position. Which one of those methods you use, is mostly a matter of personal preference. Soldering while straight has lesser risk of weakening the tie web supports via melting.
You can also place the sliding and fixed rails opposite one another, but it will leave you with missing rail on one end when you bend it.
Related Note: Insulating gaps can be a problem on curves because of the bending tension. Since they can't be soldered, the bending correction force has to be conveyed through the tie webs alone. An insulating joiner usually has very little strength, it's mainly there just to align the track ends. I avoid block section ends on curves.
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K&Srwyco
Member
The flex track I'm using PECO 83 has no fixed rail. The ties are grouped in pairs and then alternate between the rails. I guess thst design pretty much eliminates the problem Diesel is describing and providing a solution for. However i could say when working with this track you don't want to fiddle with it to many times (curve and straighten repeatedly) prior to fixing it in place. Otherwise the ties all end up looking like an accordion.
GGNInNScale
Granite Gorge and Northern Again
When joining Atlas flex sections I take a sharp Xacto knife and slice through the little nubs that hold the track to the rails. Cut back two ties from the end of the rails. Then, using the tip of the blade, scrape the top of the first tie under the rail. This gives a bit of relief for the rail joiner to fit without bending the tie down or making a bump. Then, put the rails together with a joiner, a touch of rosin flux, heat the outside of the joiner and rail. Flow a bit of rosin core lead-tin solder from the outside of the joint area. Let it cool, then repeat on the other rail. The soldering also softens the ties, which helps keep everything level. Makes a really solid mechanical and electrical joint.
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