Soldering...for beginners - please keep it simple

[Tim Mackey]

Just the basics please, and relevant to the likely things encountered by beginners when dabbling with electric flight

Edited By Timbo - Moderator on 25/08/2009 22:00:05

[Stephen Grigg]

I quite enjoy soldering especially the bit where a lump of smoldering solder lands on your finger,its such fun trying to get it off. But its the right temperature thats the thing isnt it ?

Edited By Timbo - Moderator on 25/08/2009 23:17:02

[Tim Mackey]

Well yes, heat and cleanliness.

I am linking to a video that Dusty kindly dug out for us

  Its not without fault, but until someone finds me a better one ( preferably not American ) then it will have to do.

 

By way of a summary, my tuppence worth is....

 

1) Use a good hot iron- around 30 Watt is minimum in my opinion - and even more importantlt, ensure it has a good large tip mass - the instant heat "guns" are an example of a tool which although high wattage - is rubbish for most heavy type soldering.The low mass of the tip allows all the heat to transfer away almost immmediately you touch the work. Some users have managed OK with these devices on the smaller type of jobs, but if you wish to properly solder heavy guage cables, and battery tags etc, then they are pretty hopeless IMO.

 

2) Clean the parts first, scrub with wire wool or scotchbrite pads etc, ensure if you do use wirewool no loose wire strands are going to short out you connectors etc!

 

3) "Tin" both the iron tip, and the parts to be soldered first, with a nice shiny thin film of solder.

 

4) Heat the work  - NEVER apply solder to the iron tip and try to "carry" it to the work. Once the work is hot enough, touch the solder to it, and it should "flow" nicely and result in a shiny smooth joint.

 

5) Make up some sort of jig, or use a "helping hands" type device to hold the wires and connectors etc Steady whilst you work on them. Heres a tatty and old well used jig I made up years ago. A scrap of wood, and some old wooden clothes pegs - also has holes drilled to take various connectors / plugs..... You get the idea

 

6) After cooling, give the connection a good firm tug and twist etc, if it lets go, you have failed, and should start again. The finished job should have a nice bright shiny finish, not dull...which could indicate a "dry joint".

 

Edited By Timbo - Moderator on 25/08/2009 17:40:06

[Tim Mackey]

You Tube Link...thanks Dusty

[Nobby159]

It's always a good idea to have a piece of damp natural sponge handy to wipe off the tip and keep it clean, failing that a piece of damp cloth or kitchen towel, but try to avoid foam sponge, as the fumes can be toxic . Once clean touch the tip with fresh solder (this helps with heat transfer).

[Martin Harris - Moderator]

I find my 40 year old Weller 140W "instant heat gun" (in constant use since I was 14) is excellent for the job.  It certainly has no inherent heat capacity but the tip is being almost instantaneously heated constantly and mine is more than up to the job for 4mm and Deans connectors.  Maybe the modern ones are different but they still use the same tips.

 

Edited By Timbo - Moderator on 25/08/2009 23:20:53

[Tim Mackey]

 I guess these guns just about OK for bullet connectors and the like, but once you start getting into making up battery packs etc its useless. I use a 100 watt hammerhead iron for really heavy stuff - but my days of soldering nickel cells end to end, are urrrrr, ended

Edited By Timbo - Moderator on 25/08/2009 23:18:58

[Boots]

IMPORTANT

instant soldering irons produce an intense magnetic field at the soldering tip , this field is strong enough to distroy  semiconductors eg  diodes,transistors, micro processors just what your esc ,receiver  is full of. My choice  would be some thing  like an antex 30/40 w with about 5mm chisel tip, thin tip for small wires and a large flat face for big wires. Check that the iron temperature is suitable for the solder you use.

Some types of solder are unsuitable for iron clad tips. eg weller tcp iron clad tips and savbit solder -there is a reasonably new lead free solder being used and it has different properties and i suspect melting temperatures.

 

Maybe some knows the full story on this

Edited By Timbo - Moderator on 25/08/2009 23:22:08

[Tim Mackey]

Good point there Boots...TY

Most if not all the solder which is readily available these days is going to be lead free - and its not compatible with any previous soldered joints which were made with lead+tin solder.

I have never used lead free, having seen what was planned several years back, I stocked up big time with huge rolls of "regular" 60/40 lead tin stuff - having heard that getting good results with the lead free "green brigade" stuff was difficult.

I also very much like the LMP stuff ( Low Melting Point ) which has a highish silver content. it also has the added bonus of drying very quickly and with little or no "bloom".

However, I am in danger here of straying into too much detail and tech stuff for the purpose of this beginners section.

[Brian Parker]

  May I just add,
 Practice.

 Perfect soldering can only be achieved through practice.

[Former Member]

[This posting has been removed]

[Tim Mackey]

As I say, its not perfect in several ways, but if anyone can link to, or do their own which is better, then please let me know

[Steve Hargreaves - Moderator]

Just another thing to add......lead was banned from commercial solder by the EU not so long ago & this means we now usually buy lead free solder (silver & tin) which has a higher melting point. Soldering irons usually have a fixed temperature (unless you buy an expensive "adjustable" unit) set at the design stage. Older irons will be set to melt 60/40 tin/lead solder & may not get hot enough to melt lead free solder properly. Also the fluxes in lead free solder don't do the old iron clad bits any good & can destroy them in pretty short order.

 

What does all this mean....? If you have an old iron & consistantly struggle to get a good joint it may be that your iron doesn't work too well with the new solder. Solution....buy a new iron or find some 60/40 leaded solder it is still available (& better in my opinion....if you consider that military, aerospace, medical & any "safety critical" equipment is exempt from this ban on leaded solder then what does that tell you.......)

 

Just my 2p worth.....

[Adrian]

When soldering connectors to the battery, we strip just ONE wire, solder it and then insulate it, BEFORE we strip the other. Otherwise a small slip may result in a short circuit.

 

[Tim Mackey]

Excellent point Adrian, and very good advice.

[Chris Bott - Moderator]

I too use LMP solder, exclusively. I've recently bought more from RS Components.

It is similar to 60/40 but has 2% Silver content.

The Lower Melting Point  is useful so as not to heat batteries so much.

It has no "pastey state" i.e. it changes from liquid to solid instantly.

Any movement during the "pastey state"  of 60/40 is one thing that causes a dry joint.

It also seems to "wet" the components during tinning much easier.

I just find it easier to work with.

 

Chris 

 

[John Cooper 1]

Why electric irons? What's wrong with 8oz of copper and gas? "well clean, well hot, well tinned-job well done!

[Nobby159]

I too use Weller gas irons most of the time, very handy, but warning not for confined spaces and watch the exhaust it can ignite balsa and plastic in the blink of an eye

[Tim Mackey]

Because most beginners will be more likely to have access to / own a 21st century electric heating stick

I also use a gas torch and copper tip for really heavy work occcasionally.

 

[Nobby159]

Kept in your flight box Timbo, something akin to the Weller Pyropen with piezo ignition is ideal in an emergency and not just for heavy work. Handy self contained, quick instant heat. Most also come with a sheild to shrink 'heat shrink' insulation, for that quick repair.

[Tim Mackey]

Yes, I have a small catalytic style gas iron in my flight box too Nobby

[Nobby159]

Thats the word I was trying to remember Timbo, good on ya.

Please delete this posting once read if you want

Nobby

[001]

To add to the above, if changing or adding connectors to a battery, do not cut through both wires at the same time or you might lose a few eyebrows. (Obvious, I know).

 

And strip the insulation from one wire at a time keeping the other insulated at all times.

Then strip the other wire and solder the other connector.

 

 Use red heatshrink for the + and black heatshrink for the - rather than one colour.

[Tim Mackey]

All good points Richard - TY

[Chris Channon]

Hi all, if you solder up loose battery packs, use a bit of emery or a dremel sanding drum to clean the battery terminals to get rid of the plating on the terminals.

 

Soldering guns work well enough to solder packs, provided that all the work is  clean, i have been using a German " Blitz " soldering gun for 28 years, only ever replaced the tip as required ( still has the same bulb !! )

 

Maplins do a 40 watt soldering iron with both needle point and large round tips supplied.

 

Regards as always

Chris.