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kljucd1
20-11-2007, 09:04 AM
Hi,

I have a soldering iron, and everytime I try to solder anything all I get is little solder balls that won't stick to anything.

What am I doing wrong and can anyone point me in the direction of a good soldering guide, I looked for one but I haven't found any that explain why problems occur.

Anyway thanks for any help. :)

Daniel...

bird
20-11-2007, 09:08 AM
Daniel, you need a flux in your solder - this is a compound that maks it flow and not just stick to itself. Buy some resin-cored solder from a local dick smith or jaycar (ask them about this) and they'll sort you out.

There are several types of solder, make sure you get the one suitable for electronics work (I assume that's what you're doing?).

cheers, Bird

kljucd1
20-11-2007, 09:13 AM
Hi,

Thanks Bird, you are right, it is for electronics. I will go to Dicksmith on the weekend and see what they can do for me.

One other thing, my soldering iron has temperature controls. What is the practical difference between low/medium/high temperatures? Is there a setting that is more appropriate for electronics?

Thanks again.

Daniel...

Lee
20-11-2007, 09:17 AM
This happens to me if the component you are soldering isn't hot enough - when I solder to a plug or something, I always hold the iron to the plugs tag first for a few seconds at least, then bring in the wire, then the solder - if you bring all three together straight away the tag doesn't get hot enough and the solder doesn't adhere to it well.....
At least I think that's what is happening!

I don't think the temp setting is THAT important - what is important is that you use heatsink clips for heat sensitive components, and take care to not overeat things by not holding heat on for too long.....

kljucd1
20-11-2007, 09:56 AM
Hi,

Thanks Lee, I usually just use a medium temperature anyway.

"There are 10 types of people in the world, those who understand binary, and those who don't" :lol:

Daniel...

Dujon
20-11-2007, 10:33 AM
Daniel: Bird and Lee are correct.

There's an old saying 'heat the job not the solder'.

Using excess heat will cause solder blobs just as will not properly heating the surfaces to be joined and adds the risk, when soldering circuit boards, of detaching the tracks from the base. Only use enough heat to melt the solder neatly without producing clouds of smoke off the tip of the iron. Always clean the tip of the iron and then 'tin' it prior to use. 'Tinning' is merely touching the solder on the tip and allowing the solder to form a thin film over it. You can shake off any excess, or wipe it on a wet sponge (there are solder sponges readily available at electronic shops - these are heat resistant and don't burn if too much heat is applied, unlike a common variety kitchen sponge. They normally have small slits in them in order to catch the solder). I usually wipe the tip after the completion of each joint.

While it depends on the job you are doing, if you can run the iron around the joint as you apply the solder then so much the better. As a general rule it is not necessary to swamp the job with the solder. Least is best, provided that the final joint is clean and properly done.

You will find that rosin cored solder is the norm in electronic shops. Reels do though come in different diameters. I usually keep three different width reels on hand. You will have to experiment to find out which suit your purpose. For most people a reel of solder will last a long time, so the investment is well worth it.

*edit*

Forgot: As well as tinning the tip of the iron; if you can, also tin the components.
I hope that all makes sense.

Outbackmanyep
20-11-2007, 11:55 AM
Sometimes to help clean the iron tip i usually use a wire brush or wire toothbrush thingy, you need a little amount of solder on the tip before applying it to the job, try not to make a ball of solder rather coat the tip in fresh solder to help heat transfer to the job, if you then apply solder to the part of the tip that touches the job you'll see it flow, once it flows remove the iron.
I guess theres many ways to solder but me using soldering irons almost every working day for the past 10 years you get used to watching how solder flows. Temperature is important, if its too low you get the joint too hot because you leave it on there too long, you need to find a good temp where the solder will react instantly, i'd practice on a few bits of scrap pieces you have around to get used to the process.....
Cheers!

PS...resin cored solder is best, you have to have very good clean joints!

erick
20-11-2007, 12:14 PM
Most things you are soldering will perform OK - wire, components, tags, plugs - but sometimes you are trying to solder something to which solder doesn't really "take". A classic problem are "chromed" type surfaces. One example is the earth connection in some cigarette lighter plugs. It doubles as the spring to hold the plug in place and examples I have had have been difficult. If, even after following the guidance below, the solder stills continue to "ball" on these, you may need to get in with a file and break through that surface to expose some bare metal that will take solder.

ps. I concur re getting enough solder on the iron before you touch the job. Heat transfer to the job is much improved if a good area of liquid solder is in contact with the job.

pps. don't solder with a fan or air conditioner blowing on the job, unintentionally or otherwise - they cool it too fast.

kljucd1
20-11-2007, 01:15 PM
Hi,

Some great advice guys and much appreciated. Once I get some better solder. I think I will get something to practise on because it seems to me that it would be a very skill to have.

Daniel...

erick
20-11-2007, 01:31 PM
and...........try to avoid breathing the smoke in. But that is difficult since we normally work with our head above the job!

Come up with ways to hold one of the items you are soldering - since you run out of hands very quickly! I find that a hefty pair of pliers with a rubber band around the handles makes a fairly solid "vice".

Lee
20-11-2007, 04:24 PM
And the item being soldered gets real hot real quick.... :eyepop:

erick
20-11-2007, 04:33 PM
That's just the special thermal-feedback indicator to take the soldering iron away and start blowing - frantically! :D

kljucd1
20-11-2007, 05:42 PM
Yes I found I needed three the other night :P, thats probably why it didn't work out.

Daniel...

Glenhuon
20-11-2007, 06:23 PM
Soldering is a bit of an "Art". Takes some practice, but once you have the knack its pretty easy. The main thing is to make sure all the parts to be soldered are clean and showing shiny metal. Anything thats plated (chrome, tin or nickel) needs a rub with a fine file or emery cloth as the plating has an oxide skin on it that prevents the solder from sticking. Once you have seen it flow a couple of times you'll get the hang of it.
One of those "Helping Hands" (Dick Smith or Jaycar) gadgets make it much easier when soldering small objects.


Cheers
Bill

KG8
20-11-2007, 07:26 PM
Just in case it hasn't been mentioned' The trick is to get solder onto each part first, the wire and the component seperately. Then you can bring them together and join them easily. I often use a file or a bit of sandpaper to clean the surfaces of older components too as this helps the solder adhear easier.

kljucd1
20-11-2007, 09:25 PM
Hi,

Lovin the ideas that are flowing here guys, thanks again. I have just found an old reel of resin core solder in the shed and will give it a go.

Daniel...

erick
20-11-2007, 11:49 PM
Here's another trick (but can be a bit dangerous!). Get plenty of solder on the two halves you want to solder together. Balance or hook the iron where you can reach the tip. Hold the two halves of the job together, one in each hand, and touch them to the tip until the solder melts and combines, then carefully remove from the tip and allow solder to set. Have to be careful not to upset the iron and have a hot iron falling or swinging around. :scared:

KG8
21-11-2007, 05:56 AM
I don't know if they still on special but I just bought an excellent little 80Watt gas powered iron on sale at Dicksmith for $50. It can solder, has a hot air blower tip for heat shrink, a hot knife for cutting plastics and a nozzel that can deliver an intense flame which is excellent for heating and soldering large lugs etc which are almost impossible to solder with a conventional iron. here it is at full price.http://www.dse.co.nz/cgi-bin/dse.storefront/en/product/T1105?id=stechp

wasyoungonce
21-11-2007, 10:43 AM
Daniel.

Make sure your equipment is clean. electronic solder is lead/tin (60/40 ratios) (with flux in the core) and thus oxidises. Clean old solder by wiping/scraping off oxidation.

Keep your Iron tip clean. DSE sells a tip cleaner copper/brass swarth cup that is excellent. After cleaning, "tin" the tip by applying solder, melt it across all of the tip and re-clean the tip. It is now ready for use. If necessary do this often when soldering.

Set Iron temp to 320 to 340 degrees C..if it has a temp setting. Turn your iron down when not in use.

Keep your work clean, the items you want to solder. Clean the component legs, pads wire ends etc of oxidation.

Try to be quick, heat the job leads and component pads equally, let it heat then apply solder to the tip, pad and lead junctions at the same time. This should take no more than 3 to 5 seconds.

Don't apply too much, more is not better. Try to get a concave fillet of solder between items to be joined.

Use liquid flux on the joints before you solder. This helps flow. Clean flux off when your finished with a flux remover.

Inspect your work with an eyepiece. You would be surprised how bad a good job can look under magnification. But don't be too pedantic, re-doing a job many times can damage components/melt insulation and make the job look worse.

Use de-solder wick (of appropriate size) to remove old solder. Be sure you use some flux on the wick and it'll suck up solder like a cat cleans a milk bowl. Usually you'll need a slightly higher Iron temp to perform de-soldering with a wick. Place the wick on the job and the iron on top, let it heat and apply solder to flow the heat and the wick will do it's work.

Here are 2 online links. Notice that in both they use a "spade" or "chisel" iron tip. This is not the tip to use on a general component cct board work. It is too narrow a wedge shape and cannot apply heat to the pad and lead evenly. You want the "land" area of the iron tip to be flat against the pad and the tip to be against the component lead.

http://www.robotstore.com/download/How_to_solder_1.pdf

http://www.epemag.com/solderfaq/pictures.htm

You need a wedge shaped tip for cct boards. Something like the Weller MT10, MTG20...depending upon the work.

http://www.arcade-electronics.com/weller%20soldering%20iron%20tips.as px

or you could go all out an train to NASA standards:

http://www.hq.nasa.gov/office/codeq/solder.htm

Best thing for you to to is to practice! Avoid breathing solder fumes!

Have fun:)

[1ponders]
21-11-2007, 11:18 AM
Maybe some of you boffins can get together and do up a "10 easy steps to soldering" or something similar for Mike to post in the Project/Articles section of the site. Maybe even include a couple of short mpegs of the critical points.

I certainly need all the help I can get. :ashamed:

wasyoungonce
21-11-2007, 11:31 AM
Good idea. I have time and can do it after years as an Avionics Tech I should be able to write a quick precises about soldering.

All I need to do is learn how to knock up a .pdf.

Anyone know of a free pdf writer that I can use.

edit:

under control, pdfforge

http://www.pdfforge.org/products/pdfcreator/download

[1ponders]
21-11-2007, 12:36 PM
Can you throw in an Mpeg or two :D

wasyoungonce
21-11-2007, 12:50 PM
I can but I think my camera resolution and lack of macro will be limiting factors.

P.S.

I'm still after a free PDF editor

erick
21-11-2007, 01:07 PM
http://www.pdf995.com/

kljucd1
21-11-2007, 08:56 PM
Hi,

Thanks for the links wasyoungonce, looks like I got me some reading to do!!




That is a good idea, can't wait to read what you have wasyoungonce. I can convert to pdf if you send me a file.

Thanks again :D

Daniel...

wasyoungonce
21-11-2007, 09:52 PM
yep no problems. I'm about 1/4 way thru it already but I'll need time to try mpegs etc.

I found a few proggies to convert pdf's but I wanted to extract some data from on line pdfs to use..alas this is quite difficult in that not all are created equally, so, it's try from scratch.

I'm also trying to figure out how to do macro pics from my camera.:lol:

Inmykombi
27-11-2007, 07:08 PM
Hi to all.
I have seen a calculation method and also a spreadsheet that works out the cals for you with regard to making dew heaters.
If anyone can tell me where it is in the IIS world, I would greatly appreciate it.

:help:

Lee
27-11-2007, 07:44 PM
Try here (http://www.iceinspace.com.au/index.php?id=63,292,0,0,1,0)
:D

Inmykombi
27-11-2007, 09:04 PM
Thanks heaps Lee.
Its Greatly appreciated.
I need to move quick to make one for my new scope before the Christmas Party at Mangrove Mtn. on the Coast here.

Cheers.

Lee
27-11-2007, 09:42 PM
I made two up using info from the link - but used nichrome wire instead - work really well, no more dew....

Inmykombi
27-11-2007, 10:23 PM
I tried to make one with nicrome wire, but got it all tangled and into a big mess with multiple turns of wire around the scope.
What a mess.
resistance was too small when I finished..aaaaahhhhhhhhhhhhhh....
Anyway.
So I gave up on the wire and hence my call for help.

Geoff

Lee
27-11-2007, 10:39 PM
2m wire = approx 27 ohm
12V source gives about 400mA at 5W or so.....
For my 100mm scopes needs about 6 turns around the dew shield - you do need to wind carefully though!

sailormoon
05-12-2007, 02:20 PM
It always help if you use gravity to slush the metal into place