Soldering to a decoder socket

[unsoundmove]

HI, i need to solder three wires from lighting circuit to a 21 pin DCC socket. It is such a delicate job, with the solder points being less than 1 mm across and my cheap existing fine tip soldering iron doesn't generate enough heat right at the tip to do the job. Grateful for any advice. I am considering buying a temperature controlled soldering station as recommended elsewhere on here.  Thanks...

[peterfgf]

Do get a temperature controlled soldering iron.  They are a worthwhile investment. I bought an Atten AT60 from RS Components and I'm very pleased with it (it replaced an el-cheapo from Maplins, which ably demonstrated the proverb "buy cheap, buy twice"). 

Get small pointed tips for soldering on decoders.

Buy a brass wire de-solder station to wipe excess solder off the iron tip (you don't want too much on the tip).

Clean up/remove oxidation from the contact pads with a fibre glass pen, tin the pads before soldering the wires to the pads.

I use 60%/40% tin/lead solder.  It has much better flow characteristics than the replacement lead- free solders (just don't breath the fumes).

I lay Sellotape (or better still Kapton tape) over the adjacent pad terminals which I'm not soldering - keeps them clean- but still check afterwards that you haven't accidently bridged the pads with solder.

Hope that helps - other people will be much further up the learning curve and give more advice.

Peterfgf,

 

[unsoundmove]

Thank you. What sort of temperature would you set it up for this kind of delicate job ? 

[Roy Langridge]

1 hour ago, unsoundmove said:

Thank you. What sort of temperature would you set it up for this kind of delicate job ? 

It is going to depend on the melting point of the solder you are using. In an ideal world you would use a solder with a slightly lower melting point than was used for the original solder joints, meaning that you remove the risk of affecting the original joints. 
 

Roy

[peterfgf]

2 hours ago, unsoundmove said:

Thank you. What sort of temperature would you set it up for this kind of delicate job ? 

The 60/40 solder I sue has a melting point range of 183-188deg.C. and I set the iron at 380deg.C.  

It always a bit of a compromise but this temperature manages to make quick, well melted and effective joints for me.  Not a lot of heat goes into the parent material if you are quick about it.

Peterfgf