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Advice for novice solder-er

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Posted by Anonymous on Saturday, March 6, 2004 1:54 PM
Here are some tips.

1. Move the first two or three ties back from the end of the rail. You have to cut a litle bit of plastic that spaces the ties from the underside of the track. Be carful not to break the tie plates.

2. Shine up the metal that are to be soldered with emory cloth or fine wire bush. That's necessary for brass but nickel silver is usually doesn't need it unless it's dull or dirty. Use a Q-Tip to clean oils off the surfaces with rubbing alcohol.

3. Use a soldering gun (140 / 100 watt). The higher the wattage the faster the metal will heat up in a small area. Anything less will only melt the ties.

4. Use very small diameter (32 AWG) rosin core wire solder. The same stuff you use to solder electrical wire. Smaller diameter solder makes it eaiser to control the amount of solder on the joint. Don't use acid core solder or acid flux.That will only cause corrosion no matter how well you clean it off. If you do want to use a flux, use a rosin flux. I only use flux on rally big things like plumbing or metal that will not need to make electrical contact.

5. Use hemostats for a heat sink. You can find them at tool supply stores. Buy a large enough one so it won't damage the rail. There shouldn't be a lot of pressure to close the clamp. Clamp it between the joint area and the ties to protect the ties fom melting. If you are fast enough at solidering, you might not even need it.

6. Keep the gun tip clean. Wipe excess solider off the tip by swiping it quickly with a damp (not wet) sponge. There only needs to be a thin film of solder on the tip and it must be shinny when hot. If not, the heat will not tranfer well at the point of contact but will cause the parts to heat up enough to melt plastic, not the solder.

7. Tin the parts separately. Tinning means to prepare the part for soldering by applying just a thin coat of solider on the parts. Doing this assures that each part has taken the solder. Only solder the outside of the rail and joiner.
First heat up the soldering gun then touch the tip to the area where you want solder. Touch the solder close to the tip but NOT on it. The instant the solder melts, back off. The important point here is to heat the part to melt the solder, not the tip of the gun. Solider flows towards the heat sorce. That's the trick in solidering.
If you apply too much solider, wipe the melted solider with a damp sponge. Electronic supply stores sell de-solidering wicks and other devices that remove excess molten solider. They are handy but are used mainly for de-solidering PC boards.
Next, connect all the parts. If you can't slip the joiner on the rail, apply heat to rail just long enough to melt the solder as you are slipping the joiner on. Once the two sections are connected (be sure there's no bump), heat the joint in the middle and from the bottom. Add just a DAB of solder. The important thing here is not to move the parts untill they are cooled. I use two pieces of 2"x4" wood to raise the track off the workbench and weights to hold the track down.

Bottom line is clean the parts and the tip of the gun, use high heat and be fast, tin the parts first with as little amount of solder as possible, assemble the parts carefully and use only a dab of solider. If the solder on the joint doesn't melt within a few seconds, stop. Something isn't right. Either the tip of the gun is dirty or it's not getting hot enough. Be sure the nuts that hold the tip on are tight and making good clean contact. Replace the tip when it looks worn down.
Another thing that I use is magnifying goggles and lots of light. It really helps to see what your doing.

G.
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Posted by Anonymous on Friday, March 5, 2004 6:36 PM
Use a small iron, in the 40 watt range. Unless you have a lot of skill already, don't use a gun type iron like clinchvalley does. If you heat for too long, you will melt the ties. If you don't heat for long enough, you won't get a good connection. Do a lot of practicing before wiring your layout.
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Posted by orsonroy on Friday, March 5, 2004 4:42 PM
QUOTE: Originally posted by clinchvalley

I use a 100/140 watt gun and it works great. You say it's too hot and will melt the ties, NOPE. It's so quick that won't happen and you get a hot positive joint every time.

Small wattage irons (25 - 40) should be used on electronic circuit board type work. There is way too much mass in rail for them to heat properly.


I do just fine with a 40 watt pencil iron. I guess it all depends on what you're comfortable with (I saw a guy build a prototype perf board PCB with a MANUAL HEAT iron once! Remember those; you had to heat them up on the STOVE!). Generally, I feel that a soldering gun's tip is too big to do a very tidy job of soldering, especially if you're usinf smaller rail. My mainline is code 75 and some sidings are code 55, so I like the precision I can get using a chisel point pencil iron.

Ray Breyer

Modeling the NKP's Peoria Division, circa 1943

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Posted by ClinchValleySD40 on Friday, March 5, 2004 2:15 PM
I use a 100/140 watt gun and it works great. You say it's too hot and will melt the ties, NOPE. It's so quick that won't happen and you get a hot positive joint every time.

Small wattage irons (25 - 40) should be used on electronic circuit board type work. There is way too much mass in rail for them to heat properly.
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Posted by Anonymous on Friday, March 5, 2004 12:26 PM
remember what you did with the peices of track when you cut off the extra track and ties .
you can use the ties to replace if you happen to melt a few also.
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Posted by Anonymous on Friday, March 5, 2004 11:55 AM

Here's a good link to answer "What is flux?"
http://www.finishing.com/Library/flux.html


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Posted by nfmisso on Friday, March 5, 2004 11:53 AM
QUOTE: Originally posted by jchain
[br} I have flux in the core of the solder itself. Isn't that god enough?

No!! You need both.

Here are some examples
http://www.x-tronix.net/webshop/product_info.php?products_id=79
http://www.action-electronics.com/kester.htm#Flux
http://www.elexp.com/sdr_0720.htm
Nigel N&W in HO scale, 1950 - 1955 (..and some a bit newer too) Now in San Jose, California
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Posted by Anonymous on Friday, March 5, 2004 11:39 AM
OK, thanks for the advice. Certainly a lot more than I got in the tip sheet with my gun.

Many of you have mentioned applying flux to the piece. What is FLUX? I have flux in the core of the solder itself. Isn't that god enough?
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Posted by orsonroy on Friday, March 5, 2004 8:19 AM
You can solder just about anything with a 30-40 watt pencil iron. Anything else is overkill for what most modelers do. The only time you really need to use a soldering gun or torch is when you're scratchbuilding in brass, and need to solder large pieces of metal together.

The point to soldering is to get in, add heat, and get out, as fast as you can. Soldering something like a track feeder wire shouldn't take you more than 5-10 seconds. I just dropped 40 pairs of feeders on my second level, and it took me an hour.

Jchain: try this for soldering.

1) get a 30 or 40 watt pencil iron. The cheap Wenns or Radio Shack versions are just fine. Get one with a chisel point instead of a "pointy" point. The chisel point will add more heat to the area you want soldered faster than the regular tip. Adding heat fast and getting out fast will reduce the chances of you melting ties.

2) Prep the tip. Clean a new tip cold with a little alcohol and a couple swipes with a flat file. Turn the iron on and let it heat up (1-3 minutes). Dip the tip into acid-free paste flux and immediately add a SMALL amount of solder. Wipe the tip off on a wet sponge, and you've got a tip that's ready to go. While you're soldering, wipe the tip off after every use on the sponge (Radio Shack makes a nifty iron holder with a sponge at the base. I highly recommend buying it!)

3) solder a feeder to the rail. Don't bother to pre tin the feeder wire. If it's clean, it'll solder just fine (I work in electronics and we don't pretin ANYTHING that goes onto a PCB). Get a cheap brush and add some flux to the area on the rail you want to solder. Only add a little, or you'll have to clean it up (flux helps heat transfer from the iron to the work, meaning you'll spend even less time at the joint). With one hand, hold the feeder wire alongside the rail. With your second hand, apply the chisel point to both the rail and the wire. The flux will start to boil, which is a good thing. Wait until it's almost burned away, and then with your third hand (!) touch the solder to the rail and wire (after it's heated for 1-2 seconds), but try not to touch the point of the iron (no big deal if you do, but lots of solder on the tip will slow heat transfer). Let the solder flow for no more than a second or so, and then remove the solder and the iron. Wipe the solder joint with a sponge and give it a tug test. If the joint is good, the wire won't go anywhere. Wipe the iron tip off on the sponge and move on to the next feeder.

Remember that you don't need a lot of solder to make a good joint. In fact, less is generally better. To help reduce the need for multiple hands, bend the feeder wire into an L shape that conforms to the rail. I generally try to make them so they sit tight to the rails without me having to touch them at all. For your first feeder witre soldering projects, I'd practice on a scrap piece of track. It's better to practice on scrap than on your real layout! Heatsinks are useful, but not generally necessary for soldering feeders. Add a wet sponge to the tracks near where you're soldering at first; it's a better heatsink than clips.

Anyway, soldering is pretty simple. It took you longer to read this email than it should take to solder two feeders!

Ray Breyer

Modeling the NKP's Peoria Division, circa 1943

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Posted by Anonymous on Friday, March 5, 2004 8:03 AM
I learned by trial and error while pratcing on a scrap rail and wire.
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Posted by nfmisso on Friday, March 5, 2004 7:59 AM
I have no trouble soldering wires to code 100 Atlas flex with a 30W pencil iron.

1. as everyone above says - get things clean.
2. use electronics grade flux, I use the paste type, others like the liquid, apply this to both parts to be joined.
3. keep the iron hot and clean, do NOT use water, use something like this:
http://www.all-spec.com/cgi-bin/fccgi.exe?w3exec=showitem&promoid=&w3site=ALLSPEC&w3path=vend&w3product=599B-02
also see:
http://home.earthlink.net/~n0ss/soldering_iron_tip_cleaner.pdf
4. heat your gun/iron up, clean it as described in the links above, tin the tip with solder.
5. apply the hot tip to the each piece to be soldered, and melt some solder on to each.
6. clamp the two pieces together (alligator clips work well), put a little flux on the joint.
7. heat it up, and a little solder if required. It is important; get the pieces hot quickly. Keep your iron clean.
8. Your finished joint should have the minimal amount of solder possible, and it should be shiny, not dull and cloudy. Dull and cloudy indicates a "cold" joint, meaning the pieces being joined were not hot enough.

USE
1. rosin core electronics solder, thin stuff, like .025" or .031", or smaller.
2. electronics grade rosin flux.


Nigel N&W in HO scale, 1950 - 1955 (..and some a bit newer too) Now in San Jose, California
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Posted by Big_Boy_4005 on Friday, March 5, 2004 7:26 AM
I always used to have trouble using low wattage pencil type irons for doing work on track. I could never seem to get enough heat on the work to do the job. I use a large high wattage gun, and that makes a big difference. Those small pencils are OK for electronics work, but not much else.
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Posted by Eriediamond on Friday, March 5, 2004 7:01 AM
jc, this is kind or hard to explain in a forum in few words but will try. First you must clean the solder gun tip. a small fill can be used. On the cold tip, file the old solder off, taking care not to file away the tip itself. You just want to remove the solder and oxidation from it. Next heat the gun up and coat the tip with solder. While the tips is still hot you can wipe it on a wet sponge to remove access solder. Now the gun should be ready for use. Next you have to "tin" the objects you are soldering. Lets say, feeder wires to track. After removing the insulation from your wire, apply flux to the exposed wire, heat you gun up and apply som solder on the tip, just enough to make it look wet, not a big drop or glob. Hold the hot tip to the wire and you should see the solder flow from the gun to the wire and a nice even coat of solder form on the wire. Sould look like it is painted on. Do the same proceedure to the rail only be careful to apply just enoug heat to flow the solder and not melt the ties. Practice on some scrap track. Now you should have the wire and the track ready for the actual soldering. With the soldering gun tip hot add a bit of solder again to the tip like you did for the tinning operation. With you wire tip bent to lay against the rail, hold it inplace and touch the hot tip of the gun to it. Solder shoud readily flow into the joint. remove the gun as soon as this happens. Should have a nice solder joint. Just practice on some scrap and you will soon master the art. In closing, make sure you are using rosin core solder or non-flux solder for electrical purposes For flux I preffer the liquid over the paste but either can be sued. Good luck, Ken
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Posted by Fergmiester on Friday, March 5, 2004 6:35 AM
My personal experience with solder is as follows:

I use a 40 watt soldering pen, this is good for light to medium work but does not have the heat for heavy and large objects.

Keep your tips clean
Make sure your flux is compatible with your solder
clean and remove all dirt, paint etc before soldering
Pre-solder the individual pieces, you are about to solder together, and wipe clean and apply fresh flux before joining them
I use lead free silver solder for obvious reasons
If you use a heat sinc to disapate heat away from plastic parts you will need lots of localized heat where you are soldering.
And yes I use the tip on the solder
Some metals heat quicker than others

the key is lots of heat to the area being soldered and use alligator clips to disipate the heat away from any plastic or other areas alredy soldered. nothing worse than seing everything crumple when you're on your last seam.

http://www.trainboard.com/railimages/showgallery.php?cat=500&ppuser=5959

If one could roll back the hands of time... They would be waiting for the next train into the future. A. H. Francey 1921-2007  

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Advice for novice solder-er
Posted by Anonymous on Friday, March 5, 2004 6:14 AM
I own a soldering gun, have read the 'tips' sheet and turned on the gun to melt a strand of solder once or twice. Admittedly, I don't really know what I am doing when in comes to soldering.

But, I did try to follow the advice by applying the gun tip to the metal or wire and NOT the solder. I couldn't for the life of me get the rail or the wire hot enough to even BEGIN to get that solder to run. Finally, out of frustration, I touched the solder to the tip of the gun and at least got the solder to drip on to my wire and rail.

Advice please... why isn't the metal heating up? Or any other tips that a novice needs to at least be able to solder a piece of wire and a rail?

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