When soldering joints between flex track, do you apply solder to the outside of rail and the inside or just the outside??
I never apply solder to the inside for three good reasons…first,it’s not necessary…second,I try to keep soldering time to minimum to avoid melting the ties…and third,I’m not too crazy about filing when I can avoid it.Having a hot enough iron allows me to simply contact the outside rail and solder spreads on instantly…no mess,no melting and very little filing when so needed.I also don’t solder every single joint (never on turnouts) as I like to leave gaps every three or four feet to allow expansion.My two cents…
If you are going to solder them at all, do it only a little on the outside. I don’t solder if it is straight, only if it is curved.
straight - no solder
curved - tiny solder on outside only.
Personally, I solder most joints, even straight.
I typically take a small brush and try to work flux down into the joiner before I put it on. Then I solder from the outside (definitely not the inside), using only a small amount of solder. This generally results in no solder joint visible… the solder follows the flux, essentially bonding the rails together from the bottom, the best place of all, IMHO.
I prefer to use a large soldering gun rather than “pencil” type iron. I find it heats the rail faster and results in less ‘meltage’ than trying to use a small iron. I any case, make sure the iron is well and truly hot before starting.
As others say above, I generally do not solder turnouts, and usually leave a small gap (1/16" or less) at turnout joints. I find this leaves plenty of expansion space, even with all the other joints soldered.
Forgive me for being dumb and not knowing, but why do you need expansion space at the turnouts for??
Lord_Beelzebub,
The short answer: For expansion.
The longer answer: As the temperture changes in the room the tracks expand and/or contract.
That is, as the temperture drops the track ‘shrinks’. As the temperture rises the track expands. This is all in reference to the temperture in the room when the track was first installed
This shrinking (contracting) and expanding can cause kinks , etc. to appear in the longer sections of track.
Hope this helps…
I personally solder the outside of the rail by using rail joiners and soldering no more than 3 sections of flex track in, with every fourth or so as a “floater” (just rail join, no solder). This seems to work pretty good especially in Phoenix, AZ where we get lots of temperature variation. As well, I don’t solder switches in.
Better reason NOT to solder the turnouts, REPLACEMENT when the break.
My $.02
We solder 100 % in the curves and every other in the straight sections. ALSO from testing using Latex caulk to set track takes care of the expansion since it flexes.
Take Care
I’ve had to cut turnouts out after soldering them in and recommend against it. I also recall an article some years back about iron proofing your track. Basically it required soldering all the joints and cutting the rail for expansion. I tried it on the lower level of one layout. It worked fine but this layout was in it’s own room in the house so the climate was pretty stable. It is a lot of work…
Thanks folks. I know not to solder the inside of rails, only the outside.
Texas Zephr pictures - I noticed the rail joints are staggered. Interesting and makes sense for smoother ride. I will do that where possible.
Now another question, I searched and could not find the thread I saw. Using flextrack for curves, which side does the moving rail go on, the outside rail or the inside rail.
According to Atlas, sliding rail inside:
How To Use Super-Flex Track
Super-Flex Track has one stationary rail and one that slides, allowing it to bend easily. When bending the Flex Track into the desired shape, you must keep in mind that the sliding rail must always be on the inside of the curve (closest to the center of your layout plan).
Once you are sure the sliding rail is facing the right way, tack the track loosely (in case you need to move it later) to your tabletop, then clip the excess rail, making it even with the stationary rail.