Soldering iron for rails

[bcammack]

You gonna listen to an electrician or to somebody with their NASA certificate for Military Specification electronic assembly (courtesy of the China Lake Naval Weapons Center)? [(-D] [(-D]

[rexhea]

QUOTE: Originally posted by snowey

I read on the Atlas forum where a guy said he got a proffesional electricion to solder some track for him, and the guy showed him that the joint doesn't have to be 100% clean, or even 50% clean. You can just make a scratch witha a hobby knife, wire brush, etc. and that's enough.

I think I 'll stay out of trouble with this one. But, there is a lot of difference between 120vac+ going through a connection vs. less than 20 -- particularly DCC.

Hope that Electrician wasn't one of my former students.[:D][:D]

REX

[snowey]

I read on the Atlas forum where a guy said he got a proffesional electricion to solder some track for him, and the guy showed him that the joint doesn't have to be 100% clean, or even 50% clean. You can just make a scratch witha a hobby knife, wire brush, etc. and that's enough.

[rexhea]

becammack,

You mentioned probably one of the most important things needed for a good solder joint that I forgot to add "... clean joint...".

freeway3,

It is a must that the metal surfaces be free of paint , glues, varnish, and etc... If it isn't, then more heat will be required (damaging other areas) and the contamination of the joint itself could cause a cold solder joint, i.e., bad conductivity. I always file, sand, or use a hobby knife to scrap away any foreign deposits.

If I see that a joint is going to be stubborn about heating up, I will also dab the tip of my iron with solder to help increase the applied heat (more surface area).

Also, when solding electrical connections, it is for electrical conductivity. I know there are times when we have to use it for mechanical strength., but the mechanical connection should be made before soldering where possible.

[:)]

REX

[bcammack]

I've been thinking about how to describe soldering in a concise, descriptive fashion and this is the best I've come up with so far:

Soldering is all about putting heat into a clean joint faster than it can migrate away from the joint and damage something. This is why I "wet" the contact point between the tip and the joint with just a dab of fresh solder, to precipitate a rapid flow of heat from the iron tip to the material being joined. This is also why having a clean, well-tinned tip is critical. Rapid transfer of heat from the iron to the joint gets the job finished before the rail away from the joint can get hot enough to start melting ties.

Solder should be applied to the side of the joint away from the iron's tip. This takes advantage of the liquid solder's tendency to move towards the heat source via capillary action.

Materials being joined with solder will benefit from being individually pre-tinned with solder before making the final joint. For joining feeder wires to rails, at least pre-tin the feeders. They'll be easier to pre-form to the desired shape and will tend to stay that way during the soldering job.

If you keep a toothpick between your index and forefinger while holding the solder between thumb and index finger, you can quickly let go of the solder and replace it with the toothpick to hold an awkward joint in place while you remove the iron from it.

If you practice, you can solder feeders on code 80 N scale track with a 30-watt iron and never melt a tie. [:)]

[cwclark]

I like the weller gun to solder my track..but as stated above it is all in technique...a dab of solder paste is a must, diameter of the solder is an added bonus ,(I use relatively thin to medium diameter solder)...and a quick, even, heat up and solder flow technique does the trick...practice your soldering technique on an old rail until you get good at it before moving onto your layout...soldering is easy once you've learned how to do it....Chuck

[ClinchValleySD40]

I use a 100watt gun for attaching drop feeders and soldering rail together. Works super fast, get on and get off real quick. No damage to anything.

[snowey]

QUOTE: Originally posted by freeway3

What wattage iron have you had success with soldering rails - HO, code 83? I have a 30 watt iron for smaller stuff, I suspect this is too small.

I don't want to invest in resistance equipment, although I know that's probably the best for this application. I just want to get the best iron (or gun?) for rails.

Thanks for your input!

Ed

as you can see, everyone has their own preference, and there's no "right" answer. I have a 35 watt pencil tip iron, and have used it succesfully on HO code 100 rail, and HO code 70, and N scale code 80. But, I've also had good results using an 80 watt iron, with a chisel tip. I find however, that with the 35 watt one, I don't melt many ties.
Like someone else said, it just takes practice to learn what's right for you. I've heard of people who like a 100 watt, chisel-tip iron.

[rexhea]

I use a 35 watt type soldering iron with a very narrow chisel tip. This allows you to get to the joint between the rail and the connector and stay away from the ties. If I might add, when you apply your iron, you can look closely at the joint and see a heat "ripple" start to spread (only a couple of seconds). Apply your solder then and only to the metal and not the tip of the iron to prevent a cold solder joint. If the metal is hot enough it will accept the solder and flow throughout the joint . Remove the iron at this point. If you do have a tie curl up on you, just form it back down while its hot.[:D]

Soldering, like welding, takes practice.

REX

[bcammack]

I think I read about it on trainboard. Only problem is that there is no temperature regulation with those. The longer it's on the hotter it gets, so you can burn things up. Might be handy for soldering splices and such.

A good soldering iron or soldering station can be a lifetime investment. My iron is over 20 years old now. I recommend a soldering station because it has an adjustable temperature range, a dedicated, stable holder for the iron, and a place for your tip cleaning sponge.

[JCasey]

Hi All,

Has anyone seen the ad on TV lately for the battery powered soldering pencil called ColdHeat for $19.95 + S&H. It seems too good to be true, and we all know what they say about that. Think it would work for soldering rail?

Thanks, John

[bcammack]

I use a 25 watt Weller on my Code 80 N scale rail. It's not the iron or it's wattage, it's mostly technique and practice. You have to wet the joint with a dab of solder as the iron hits it so the heat will flow quickly into the rails. The quicker the heat flows into the rails, the quicker you can melt the solder into the joint and withdraw the iron. This keeps you from melting the ties. [:)]

BTW - use a chisel tip, not a pointed tip.

[Javern]

I have a Radio Shack dual heat 200/260 watt gun, it has built in work lights. It heats very quickly and solders track like a breeze. I have been using it for years and years on most anything and have a good technique down, I don't even use the low watt pencil type units anymore.

[freeway3]

What wattage iron have you had success with soldering rails - HO, code 83? I have a 30 watt iron for smaller stuff, I suspect this is too small.

I don't want to invest in resistance equipment, although I know that's probably the best for this application. I just want to get the best iron (or gun?) for rails.

Thanks for your input!

Ed