Soldering Flex Track for Curves

[richhotrain]

Hmmm, nobody seems to like my idea about using Shinohara curved track sections.

All of the suggestions have been to solder sections of flex track together.  When doing that, how do you approach the task? 

Do you lay two pieces of flex track upside down and solder from the bottom? 

Upright and solder from the sides?

Someone once told me to drill a small hole through each rail about 1/4" from the end on each piece of flex track and use "U" shaped pieces of piano wire to initally hold the pieces of flex track together while soldering.  Is that recommended?

Rich

[wedudler]

Usually I use rail joiners. When soldering the flex rail should be straight. That means one piece is glued down and the second flex rail piece (3' ) are attached straight. I solder the outside from the rail and rail joiner with my 30 Watt soldering iron. Solder fast - long heating will weaken the plastic ties.

Here you see flex track and turnouts soldered together.

 

Wolfgang

[georgev]

I also use rail joiners, the same method as Wolfgang.  But I use a 120 watt soldering gun and I wait till the tip is at full temp before soldering..  I think the high heat transfers faster helps prevent the dreaded Salvador Dali style of crosstie....

I solder from the side - the heat will draw the solder into the joiner so it is barely seen.  If the solder isn't pulled under the joiner the joint is not hot enough.  I use a thin wire 60/40 solder.  The higher tin content makes for easier flow. 

George V.  

[CNJ831]

As with the two posters above, I employ rail joiners to directly connect the pieces of rail before doing the actual soldering (doesn't everyone?). However, I strongly recommend not simply attaching the two pieces of rail directly across from one another. Instead, stagger the soldering point of the two rail joints by about 4 to 6 inches. This may add to the work but almost always absolutely eliminates the possibility of a kink in the track at the jointing point between two pieces of flex. I see more poorly done trackwork on curves than any anywhere else on people's layouts. On several occasions recently folks have posted incidental photos that illustrate their soldering jobs on curves which are so poorly done I wonder just how their trains make it through without derailing!

CNJ831 

[Seamonster]

The advantage of using flex track, of course, is that you get the curve radius you want--you aren't restricted to some fixed radius. Also it's easier to establish the transition with flex track. I join two pieces together with rail joiners. Then I clamp a yardstick to my workbench, align the track against the edge of the yardstick to ensure that it's perfectly straight, then clamp the rail down on either side of where I'm going to solder. I solder the sides of the rail. I put some flux over the rail joiners, then heat it and flow solder into both ends of them.

[Heartland Division CB&Q]

Remove plastic ties at rail joiners. Solder rail joints with rails alligned with no kinks either vertically or horizontally. Ideally, solder before nailing track down. You may hold track down with push pins before soldering with rails aligned properly. As noted before, you may use flux, and you should solder quickly with a good hot iron and with solder on outer side of rails at joints.

Later, you may replace ties, but make sure you sanded them so they are less thick to prevent lifting rails at joint. Otherwise, simply install enough ballast to conceal lack of ties at joints.

The joints can be a good plice to solder wires to tracks. Heat wire first and apply a little solder to wire. Then, press wire against solder on joint with hot iron.

[selector]

I like Seamonster's method, suggestive of having to do this process at a cleared and planar surface where you know there will be no indavertent and unwanted torsions or kinks to make it all a useless undertaking once the rails are in place on the layout.  Use clamps and a straightedge or two, and soldering at staggered joiners is the way to go.  Removing, filing flat, and re-inserting a couple of ties where the inserted staggered sliding rail join is can be some work, but the results are worth it.

-Crandell

[csxns]

Rich ? here where do you get curved Shinohara track from and is it large radius.And ? to the others how many flex tracks can you solder together before bending them.Thanks.

[rrinker]

 You can solder as many together as you need, but I found that 2 three-foot sections of flex track were plenty for a 90 degree 32" radius curve. The smaller the curve radius, the less linear length of rail you will need for a given part of a circle.

 I prefer to not solder EVERY rail joint - just the ones on curves to prevent kinks. Expansion/contraction needs some place to happen, if you solder every single rail joint and your layout isn't in a room with good year-round climate control, expect kinks and bulges. Keep at least a few joints unsoldered.

                             --Randy

 

 

[tomikawaTT]

rrinker

I prefer to not solder EVERY rail joint - just the ones on curves to prevent kinks. Expansion/contraction needs some place to happen, if you solder every single rail joint and your layout isn't in a room with good year-round climate control, expect kinks and bulges. Keep at least a few joints unsoldered.

                             --Randy

I'll go one further and say, solder only the non-sliding rail if only one rail slides easily - and lay that rail to the outside.  Slide the inside rail along, and insert the joiner where it happens to end, which may be a few or a good many inches from the soldered joint.  For both, trim away enough of the top of the ties to prevent 'humping,' which, IMHO, is a major cause of joint-related derailments.

With the joints well staggered, the probability of kinking is considerably reduced - thus dealing with the other major cause of joint-related derailments.

I personally prefer to pre-curve my flex so it will stay where I put it, and hold the radius I want, BEFORE it is anchored with Latex caulk.  This includes using pliers and judicious force to curve the last few inches of rail at the end of each length of flex.  I also de-burr every rail end, and knock off the hard corner at the top inside of the railheads at every joint, whether pre-soldered or left unsoldered and floating.

My objection to pre-curved sectional track is twofold:

1. The manufacturers don't make the oddball radii I need.
2. Nobody has ever manufactured a true spiral easement with sectional track.

 

For my givens and druthers, both are deal-breakers.

Chuck (Modeling Central Japan in September, 1964 - on flex track and hand-laid specialwork)

[IRONROOSTER]

 I cut the rail joiners in half for soldered joints, that way I don't have to remove ties, just slide them back.  And I have a shorter stiff section to curve.  Also makes the joiners less noticable.  I use a Weller 100/140 soldering gun.  I hold the gun on the inside of the joint and the solder on the outside until it flows.

I soldered every joint but one on an 11'x18' oval, the one joint had a gap for expansion.  Big mistake.  All the soldered joints held so all the expansion was at the gap which was not large enough and the rail bent and twisted out of the ties.  In the future I plan to solder on curves only.

Enjoy

Paul

 

[richhotrain]

csxns

Rich ? here where do you get curved Shinohara track from and is it large radius.And ? to the others how many flex tracks can you solder together before bending them.Thanks.

I don't have any Shinohara curved track but I was looking at the Walthers web site and came across it.  It ony comes in Code 100 and Code 70, but not Code 83, and comes in various radius ranging from 18" all the way up to 36", all in 30 degree sections.  If it came in Code 83, I would snap up enough to replace all of my flex track on 32" radius and get better curves out of it.  Or, as suggested here, I had better start soldering flex trackfor this purpose.

[richhotrain]

You guys have convinced me.  I am going to start soldering flex track for curves.  Thanks for all of your help and advice.