Soldering BasicsAugust 6 2006 at 10:24 PM
|TJ Whelan (Login hetzerman)|
from IP address 220.127.116.11
Long time listener...first time caller.
I am beginning to venture into the land of photo etch and I am fine with using CA to attach the parts to plastic and often to itself. But I see many instances where a soldered joint will be much stronger than the CA one.
I have read the many posts here regarding soldering as well as Ed Sweet's excellent article on another modelling web site. The problem is that I have yet to make a decent soldered joint. I would love to have a step-by-step tutorial to see where I am going wrong.
This is what I am working with:
- Eduard Flak 36/37 PE set
- New 30W soldering iron
- Aber liquid flux
- Lead-free fine rosin core solder
This is what I have done.
1) I tried to "tin" the soldering iron tip with flux and solder. All that I got was a big bead of solder on the end of the tip and not a coating of solder as it sounds that I should have.
2) I lightly sanded and then folded a PE box into shape and applied flux along the joint where I want the solder to flow. After picking up a bead of solder on the iron, I touched it to the joint: no go. The solder would not flow.
3) I tried to heat the part by touching the iron to the part for several minutes and then the solder to the joint. The solder would not melt and run in the joint.
4) And now, I can not even get the solder to melt when I touch it to to the tip.
I have never had cause to solder in my life, so please base any replies on that fact, i.e. make it "Soldering for Dummies". I am sure that there are many "do's and don'ts" related to soldering that I am most definitely violating. Any advice here would be greatly appreciated.
there is hope
|August 7 2006, 3:26 AM |
Ok the most important thing in soldering is that EVERYTHING must be clean, (dirt and oil free etc)so lets try to get you going in the right direction here.
first we must tin the soldering iron tip, let the iron get to maximum heat then dip it in your flux, imeadately wipe it with a paper towel dipped in cold water or wipe it on a small sponge full of water. this causes what is called thermal shock and causes dirt and oxidation to come off. now just touch the tip to the flux again and then apply some solder then wipe the tip with a CLEAN dry cloth (no synthetics here as they will just melt and ruin things). if you have done this the tip should now have a nice SHINNEY coat of solder on it. If not, possable problems are the tip is badly corroded clean it up with a file until you see clean shinney metal. It is also possable that some very cheap irons have a cheap alloy core on the tip if you sand or file the original plating off they become almost worthless. assumeing you have a good tin on the tip keep a couple of points in mind tinning burns off quickly even when not soldering. you may very well have to retin the iron multiple times durring a session.
Second the same rules apply to what you are soldering
clean the surfaces to be soldered, then wipe them with a clean cloth or paper towel dipped in alchol to remove any grease or fingerprints etc. Also check the photo etch some makers coat the brass with something to keep it shinney and clean, any coating on the brass must be removed to get a good solder joint. Next apply a small amount of flux where you want to solder put the iron on the part place the solder at the point where the tip and the part meet and the solder should flow onto the part use solder spareingly or there will be massive clean if the solder dosent flow almost imeadatly the part is not hot enough either wait a few seconds more before applying the solder or you might need a Higher wattage iron. I would say 30 watts is ok for most 1/35 or smaller photoetch but large parts might be a problem as the brass sucks away the heat faster then the iron can put it into the part. Another possable problem is the tip may be to small see if the have a larger tip for your iron hope this helps feel free to drop me an email if you have any questions.
The name of the problem
|August 7 2006, 9:37 AM |
is most likely Eduard. Their sets are usually coated with nickel(?) which does not work well with solder. You have to rub the coating away so that the brass becomes visible. Then apply the flux on to the surface to be soldered and touch it with a soldering iron that has some solder in its tip. Then make the bond between the parts.
In my experience Aber flux is not very good but I admit that I have tried it only a couple of times. But if your problems will not go away you should perhaps try an other flux as well.
PS. Also Part and Voyager parts are covered with something that requires removing prior to soldering. Aber and Royal Models can be soldered stright out from the box. Lion Roar can also be soldered without problems if I remember correctly.
Sounds like a heat problem.
|August 7 2006, 1:00 PM |
The fact that you couldn't tin the iron properly and the last thing you posted (#4) make me think its related to heat. Follow Stephen's advice and make sure the iron is completely hot, is clean, etc. If you're still unsuccessful, I'd check the tip and make sure its seated firmly. Many irons have screw in tips and if not tight will tend to conduct heat poorly.
One other thing I'd recommend once you get the solder melting is to not use your rosin core solder and purchase a solid core one instead. The rosin flux in the solder you are using will tend to make it flow all over rather than just where you've brush the flux.
|August 7 2006, 10:02 PM |
A big thanks to these very informative replies. I need to set some time aside to work these issues completely through. I did try Steve's tinning advice and I still end up with non-rosin core flux dripping off of the iron like mercury, so I guess that will be my first challenge.
I will post again with my results and determine as best I can from your advice where I have been going wrong.
|August 8 2006, 6:48 AM |
first make sure your tip is clean and the parts you want to solder are clean too. Then applie some flux to the parts. Cut a very smal amount of tin (almost shave it of) and place it on the flux (not with the iron!). After you've done that all you got to do is heat everything up a but with the iron. Works for mehttp://groups.msn.com/dutchmodelbuilding
Re: other option
|September 3 2006, 2:26 PM |
Eduard PE sets are nickel plated indeed. They won't take solder unless sanded off.
Both Aber and Part sets are etched using photoactive emulsion. Aber cleans the sets off before packaging. Part doesn't, hence the dark appearance of their sets. You can sand the emulsion off using fine sandpaper. However the best way is to bath the set in potassium hydroxide solution poured to the ultrasonic cleaner. Beware, that mixture is highly aggressive. Avoid direct contact and use rubber gloves whenever maniuplating it.
As for soldering try to keep the temperature of your soldering iron above the solder melting point but below the temperature at which the liquid flux evaporates. The electronic solder (60% tin + 40% lead) melts below 200°C (392°F). However you have to warm up brass to higher degree. You can set the iron up to 350°C (662°F) with the liqiud flux still liquid.