On 1 Nov, 11:40, Fred wrote:
Hi,

I am trying to replace a couple of sub-c nicads. Something that should
be so simple is not going smoothly!

Is there a trick to soldering the tags of two cells together? It has
taken me ages and the result looks untidy. What trick am I missing?

I now find that the remaining tags are too wide for the spade
terminals, so I was going to change the terminals for wider ones. I've
not crimped before so I am unsure what size spade terminals to buy.

In tool station they describe them as 1.5, 2.5, and 6mm. I presume
this means they take 1.5mm^2, 2.5mm^2, 6mm^2 cable rather than being
the actual size of the terminal?

In cpc they list the spades as being IIRC 2.8mm and 4mm. I think the
ones I have are 3mm (2.8?) and the ones I need are 4mm. So far so
good, but they then say something about being 0.8mm. Is this the
thickness? Why don't they mention the length or are all spade
terminals a standard length?

TIA

Obviously I can't see your soldering from here, but the essentials are
suitable materials (e.g. copper and tinned surfaces take solder well,
steel doesn't), clean surfaces (no oxides), clean soldering iron
(scrape off any blackened flux & when hot - wipe the iron frequently
on a damp sponge), HOT iron and BIG ENOUGH FOR THE JOB (a little hobby
iron for component soldering may struggle), and suitably sized solder
for the job (which should contain flux). Technique, get the iron hot -
solder should melt onto it in less than a second, get a little melted
surface onto the iron to act as the contact point, firmly make contact
with what you want to solder until you have wet solder on the surface
- then add what solder you need for the job.

Overall a slightly overpowered soldering iron is better than an
underpowered one - which may tend to cook everything whilst you wait
and wait for the joint to get hot enough.

1.5, 2.5, and 6mm is probably the wire size (x-sectional area), as you
suspected.

Can't help you with the terminal size. Try swinging by a halfords
(where they'll charge you quids for a pack of 3 or summat) - but at
least you can compare what you need with what they have.