Soldering Iron. How Many Watts ?!

[backtomyroots]

Hi all,

Today I purchased a soldering iron and attempted to solder the new traxxas battery connectors to my new intellect packs. Completely unsuccessful. I bought a 40 watt electric soldering iron because it was well priced. Well, now I know that was a BIG mistake as it didn't get hot enough to fully heat the wire & solder. So, what do I need ? Would a 60 watt be sufficient ? I don't want to spend a ton of money either as I only need it to change all the connectors on my new battery packs and charger. . Cheers.

[TWINSET]

Hi all,

Today I purchased a soldering iron and attempted to solder the new traxxas battery connectors to my new intellect packs. Completely unsuccessful. I bought a 40 watt electric soldering iron because it was well priced. Well, now I know that was a BIG mistake as it didn't get hot enough to fully heat the wire & solder. So, what do I need ? Would a 60 watt be sufficient ? I don't want to spend a ton of money either as I only need it to change all the connectors on my new battery packs and charger. . Cheers.

I was recommended an 80w one, but also, the size of the tip makes a huge difference too - The big, fat wet-noodle wire makes a great heatsink - not good when you're tring to warm it up

Try to get one with a wide flat tip (like a screwdriver), not a conical/pointed one.

[backtomyroots]

Try to get one with a wide flat tip (like a screwdriver), not a conical/pointed one.

Oops, I got a skinny pointed one . Thanks mate - I'll try and exchange the iron tomorrow for some more wattage and a differrent end and get soldering !

[Mud-Plugger]

40 Watt is perfect for soldering motor and battery terminals etc. For smaller stuff I use around 20 Watts. I think everything I've bought secondhand has had abysmal soldering on it so I get the feeling that the majority of people just don't know how to solder.

If you haven't soldered before here's the routine.

1) Clean both items you wish to solder together with some sort of spirit or alcohol (IPA).

2) Next tin both items you wish to solder together. This is done by waiting until your soldering iron is up to the correct temperature (about 10 mins for a 40 Watt). Then wet your iron with some solder (This is essential to make thermal contact with the item you are going to tin) and then place it on the item to raise it to a temperature with which it will melt solder. Solder is then applied to a point on the item furthest away on it, so that the solder flows towards the iron across the item you are tinning.

3) Now place the two items together, wet your soldering iron (after you've wiped it on a sponge) and add some more solder to the joint again away from the iron. This guarantees that the whole joint is up to temperature. When you see the whole area covered with molten solder, remove the soldering iron and allow to cool (no more than a few seconds).

Note. If you move the wire before the joint has cooled, the surface of the solder may appear frosty. This is called a "dry joint" and will have bad electrical and mechanical properties and should be re-heated and allowed to cool again.

Additionally, before you take the iron to make a joint, always wipe it off on a wet sponge. This ensures that you only ever apply fresh solder to the joint which will have the correct amount of flux in its cores (to clean the joint), otherwise you will be adding solder to the joint where all the flux within the solder will have been previously burnt off.

Hope this helps.

Mud.

[backtomyroots]

Wow - that's a great reply Mud. I let the iron warm up well over ten minutes and tinned the tip. But, it just wouldn't heat up the battery wire enough to melt the solder properly. I did manage to solder the wire to one traxxas connector but it was poor and popped off. I'll jack up the wattage maybe to a 60 or 80 then practice, practice, practice !

[Mud-Plugger]

...as others have mentioned though, you really want a flat tip to get all that heat onto the joint. You must be aware though, there is science in it, and too much heat will vaporise your flux before it is able to burn off the oxides during the heating of the workpiece.

I was thinking of doing a little video sometime, but here's a nice link: http://radiojove.gsfc.nasa.gov/telescope/soldering.htm

Mud.

[taliesin]

depends a bit on the quality of the iron too. i had an 80 watt ace hardware model that was total poo and a 40 watt weller that would practically weld. 40 watts for a good iron should be plenty, but as everybody has pointed out the clean / correct tips make a huge difference.

one other tip: if you don't get the solder joint in under 5 seconds you are doing something very wrong. 5 seconds will melt most deans plugs and may damage electronics so that is a dead maximum time limit. if all is well it should be more like 2-3 seconds and done.

[Singapore_959]

depends a bit on the quality of the iron too. i had an 80 watt ace hardware model that was total poo and a 40 watt weller that would practically weld. 40 watts for a good iron should be plenty, but as everybody has pointed out the clean / correct tips make a huge difference.

one other tip: if you don't get the solder joint in under 5 seconds you are doing something very wrong. 5 seconds will melt most deans plugs and may damage electronics so that is a dead maximum time limit. if all is well it should be more like 2-3 seconds and done.

Get a weller. It will last you for life. 80W will heat up faster. At the races we use adjustable wellers, set to 450 deg. Obviously the less time it is heating the battery the better.

But look for low heat rated solder, so that it will melt quicker onto the batt. that is easier than looking for the 'right' kind of solering iron tool, and will make the job easier no matter what Watt rated tool you have.

[Stonemole]

Plus one vote for weller , i liberated a 80w one from a skip and its good for everything bar heavy duty 90 degree guitar leads (lots of metal ) and its the make of choice for were i work.

let the iron get nice and hot is the key , and be patient.

im suprised Blacque jacque has not stuck a post up as he is the soldering master.

[Mud-Plugger]

one other tip: if you don't get the solder joint in under 5 seconds you are doing something very wrong. 5 seconds will melt most deans plugs and may damage electronics so that is a dead maximum time limit. if all is well it should be more like 2-3 seconds and done.

Trying NOT to be a Nit Picker, but my detailed instructions state, apply the solder away from the iron, if the solder doesn't melt, then the workpiece is NOT hot, and consequently, no damage can occur to plastic etc, again this is a common problem misunderstood by "soldering novices" where the belief is that you are trying to add solder to a joint via the iron, the whole principle of soldering is to bring the workpiece up to temperature using the iron, and then melt solder onto the joint.

Mud.

[WillyChang]

yeah the iron is not the 'trowel' for your solder 'cement'... some ppl trying to revive the ancient art of "leading"

But look for low heat rated solder, so that it will melt quicker onto the batt. that is easier than looking for the 'right' kind of solering iron tool, and will make the job easier no matter what Watt rated tool you have.

that's the trouble with ROHS today... all the lead-free solders need hotter to melt

i hate rewiring new Novak ESCs today, takes forever to melt the solder and their PCBs

are such good heatsinks all the FETs get toasty hot by the time the wires are done.

Getting to the point where i'm removing the plastic case & clamping the ESC in the (mini)vice

to keep the heat down.

rewire with vintage solder = no hassles

[Singapore_959]

yeah .... im removing the plastic case & clamping the ESC in the (mini)vice

to keep the heat down.

rewire with vintage solder = no hassles

CUE lots of new ebay search traffic under the words "Vintage old stock solder" :D

[highflyer]

The Weller kit I have is all I need, fully adjustable heat dial and it comes with 3 assorted tips..

[backtomyroots]

Hey fellas - thanks for the replies - at the risk of sounding like a moron I solved the problem. How you ask ? Took the electronics over to the future father in law ! When he was done laughing hysterically at me he soldered them up in a few minutes . My soldering adventure came to a quick end when the new iron ended up in the garbage due to a "misadventure" or was that my "impatience". I'll try again when the temper cools down . Cheers for the help mates !