I had no trouble finding thin size rosin core solder at Radio Schack. But, they did not have flux and several places I tried did not, including a hobby shop. At an old type hardware store in town, I did get a tin of “Burnley Soldering Paste” (made in Can) 2 oz … but it says nothing on the can about rosin or not rosin. Of course, the clerk did not know. Can anyone verify if this is or is not ok to use for wiring my RR layout. Thanks!
Hal
Rosin core solder has the flux in the solder. If you clean the rail, the flux in the solder promotes flow, creating a solid solder joint.
Hi Hal,
All you need is rosin core solder. You do NOT need seperate paste.
Make sure that the “blend” of the solder is 60/40 ONLY. This is the ratio of tin to lead and 60/40 is the best in terms of flow and connection quality. Also very easy to use. Stay away from other variants (sure there are a few expensive exotics around but they have not worked better for me - 35+ years repairing electronics).
For general information: Never using plumbing solder of 50/50 or 95/5 blends. These are great for water vessels and pipes but not for electronics or electrics. They are also harder to apply and may use an acid flux. Many people say to use a very small wattage iron. I disagree. A too small iron takes too long to heat the rails or other material. An iron of about 35-45 watts is ideal after you get some experience. Heat, apply, remove iron. Best case is a temperature controlled version but no need to spend the extra money for occasional use.
Don’t forget to pre-tin everything before making the connections. It makes life a lot easier.
That Burnley soldering paste doesn’t say rosin, but mine (which I have been using approximately forever) says, “NON-CORROSIVE. CLEANS AS IT FLUXES.” It was originally given to me by an aircraft electrician, and has never caused any problems in some work where it was originally used 26 years ago.
Unlike the other posters above, I firmly believe that there are advantages to fluxing the exact spots where you want solder to adhere. Just a tiny dab on the end of a toothpick is all you need, which is why that little 2-ounce snuff can has lasted me through at least six layouts, mine and club. It’s still over half full.
As for transferring heat to the solder joint, I use a 20 watt iron for electronics, and a 320 watt Weller gun for soldering rail (including soldering feeders and jumpers to rail.
Chuck
Chuck;
What gauge rail are you soldering with a 320 watt iron? This would seem like a lotta watts for N Scale code 80 which is what I am using.
Tom.
I have soldered track and wiring with and without flux coming to the conclusion it is better to go without it. It does make the solder flow real good but I don’t think it is necessary if you use the type of solder listed by others above.
The vapors created by the flux are very unhealthy.
Bob
Thanks for your answers. The solder I got was 60/40 rosin core… and it sounds like using flux paste is in eyes of the user. I’ll probably try it both ways. My Burney tin doesn’t say non-corrosive on it, so I may still hold off using it.
Hal
If you are looking for soldering supplies, allelectronics.com is a good option. They seem to have reasonable prices and a good selection. I bought my iron, solder and flux through them.
Another supply to consider getting it tip tinner/cleaner. It really improves the conductivity of the tip so that heat transfer is quick. This is critical when trying to solder wires to tight spots (like turnout frogs) without melting the ties.
Frys electronics has a great liquid rosin flux in a small jar. check out their selection
I have to agree with you. I learned to solder in the military so it might completely wrong…but we always used flux. The flux core stuff never made sense to me. In my case it was also harder to use. Never seemed to flow right. And I had shaky hands…I can’t keep the iron in one spot very long. 
Just my two cents.
Burnley soldering paste is used primarily to sweat copper and aluminum plumbing together. I see no reason why it can’t be used for rail soldering, unless it it corrosive. I use Dutch Boy solder paste flux mysely. Never have had a problem with it. As for rosin core solder, I could never get it to work well. The joint just didn’t hold up very long. So put me in the use flux line. On the layout I’m currently working on, I have 1 main line and a small branch line. Both are continueus run with spurs. The main line has a 40 ft run and 4 spurs 3 ft +.
The branch line has a 15 ft run and 2 spurs 3 ft +. There are also 2 changeovers to facilitate interchange of rolling stock.
Sorry. Couldn’t resist tooting my own horn. I’ve built 18+ layouts and used a lot of solder and flux over the years. You will on block control. Sometimes the wiring is hard to keep up with, but I manage.
On the subject of whether or not to use a separate flux, go with whatever makes you comfortable. The fumes from the flux don’t do great things to promote health, but neither does the flux contained in rosin core solder, so you’re darned if you do and darned if you don’t. To me, using the separate flux works better. I get a much better joint with it.
Jeffrey Wimberly
Leesville, La
I’m out of my mind, but leave a message anyway.
I also have only had good luck with using flux. Everyone has there own opion, If you are woried about corrosive’s wipe the solder joint off with vineger it will stop the corrosion.
Larry
Medina 1112 and larak are absolutely right.
With rosin cored solder, the flux is in the solder. Just heat the rail, apply the solder and watch it flow. You don’t need any seperate flux. And stay clear of plumbers solder, entirely differnt stuff and game.
Cheers
Barry
A couple of key points that may not have been explicitly stated so far should be pointed out:
There are basically 2 types of flux - acidic and non-acidic. Acidic flux is used for plumbing, and it actually burns away the outer layer of crud on the metal as well as a small amount of the metal itself. Generally, you do not want to use this on MR applications, especially electronics, although I have heard of people using it on rails and feeder wires. You just have to make sure you clean the area good after you fini***he joint so it doesn’t corrode. Non-acidic flux is what you should be able to get from Radio Shack, and is generally used for all electronics and most MR applications.
Whether or not you use flux (but especially if you don’t use flux), it is important to get the contact surfaces clean before soldering them together. I use a wire wheel on a Dremel to clean the rails when joining sections of rail or attaching feeders. If you use rosin-core solder, it contains all the flux you really need to attach feeder wires, but if the surfaces are not clean, the solder will not flow very well. If you’re soldering rails together, you may not need flux, but I choose to put a little dab in the rail joiner because the area in question is a lot larger than the area used for a feeder wire.
Good luck and happy soldering!
I use an acid-free flux from Radio Shack marketed especially for electronics use. It comes in a tube, is thinner than any “paste” flux I have seen, but is somewhat thicker than “liquid” flux. I use it for MR use only, and I use such small amounts that I have had the same tube for several years and it still seems 3/4 full. I do much prefer to use flux, but this may be due in part to the fact that I do not solder on a regular basis. Without flux I can never get the solder to flow correctly. I use 60/40 solder and have great success with this method.
Ron
Rosin Flux and it’s vapors are not really that hazardious. Read the MSDS. http://www.efdsolder.com/PDF/EFD_-_No-Clean_RA_and_RMA_Flux_MSDS.pdf
Anytime you are worried about stuff just google msds XXXX and check it out yourself.
MSDS for water shows it is toxic and hazardious LOL . http://www.hsegroup.com/hse/text/water.htm
I don’t understand how using vinegar, at about 3% acetic acid, can neutralize acid flux paste. All I use is soap and water. If you ever get acid in your eyes, you would not be thankful for a flush bottle with vinegar! You’d be offered distilled water. In fact, an even better neutralizer for acid would be a mild solution of sodium bicarbonate.
Vineger neutralizes acid! Nuff said!
\Jeffrey Wimberly, Leesville, La.
I’m out of my mind, but leave a message anyway.
[soapbox]
A temperature controlled iron (Weller or similar) is well worth the cost if you are planning a fair amount of soldering. They will cope with both wiring and track soldering without generating so much heat that insulation or track are damaged.
In my experience soldering guns may be suitable for heavy electrical work but little else.
For wiring a thin 60/40 good quality rosin cored is all that is needed, no extra flux to get into places where it is not wanted (flux residue is non-conducting so can cause problems).
For trackwork, see: http://www.handlaidtrack.com/index.php where you will find the best advice I have ever seen with regard to the soldering of track
Dave…
Thanks again for responses, you have really made this thread in answer to my question very informative. Your the best!
Hal