Soldering steel wire to brass

[cctransuk]

As part of my proposed wire-in-tube turnout actuation system, I shall need to join 0.5mm. dia. steel wire to 3.5mm. dia. brass rod.

 

The brass rod has been axially drilled 0.5mm. to a depth of 5.0mm., and I need to be able to solder the steel wire into the axial holes in the brass rod.

 

I seem to recall reading that soldering steel can be problematic - will there be problems with what I intend doing, if I use phosphoric acid or paste flux?

 

Any advice will be gratefully received.

 

John Isherwood.

[decauville1126]

I've used Powerflow  ok with mild steel.

[bécasse]

You may well find it quite difficult (if not impossible) to get 0,5mm ø wire into a hole drilled 0,5mm ø. I would recommend opening the hole out slightly using, say, a 0,6mm ø drill which shouldn't be difficult. It will also give the solder somewhere to go.

If the steel wire will in fact go into the hole you have drilled, you could use Loctite 603 to fix it, just apply the tiniest drop (I use a pin to apply it) to the end of the steel wire and push it right home in the brass.

[cctransuk]

3 hours ago, decauville1126 said:

I've used Powerflow  ok with mild steel.

 

The steel wire in question is spring steel / piano wire.

 

John Isherwood.

[cctransuk]

1 hour ago, bécasse said:

You may well find it quite difficult (if not impossible) to get 0,5mm ø wire into a hole drilled 0,5mm ø.

 

The wire does, in fact, enter the hole - albeit snugly.

 

Loctite 603 was going to be my fall-back option - with drilling, tapping and a grub screw as a measure of last resort!

 

John Isherwood.

[decauville1126]

Have you thought about just crimping it? Or Loctite and crimping maybe. Possibly worth a practical test.

[cctransuk]

1 minute ago, decauville1126 said:

Have you thought about just crimping it? Or Loctite and crimping maybe. Possibly worth a practical test.

 

3.5mm. dia. brass rod with an axial 0.5mm. dia. hole is a bit 'beefy' to crimp, I'd think.

 

The load on this joint will be axial, push / pull, with a movement of 2 - 3mm. I'd be worried that the available movement would be compromised if there was any 'slippage' within the crimping.

 

John Isherwood.

[Dagworth]

Does the thinner wire need to be piano wire? Guitar string is much easier to solder.

 

Andi

[cctransuk]

15 hours ago, Dagworth said:

Does the thinner wire need to be piano wire? Guitar string is much easier to solder.

 

Andi

 

This is the wire in question - https://www.rapidonline.com/reely-high-quality-steel-spring-wire-0-5mm-x-1000mm-51-1577

 

I wanted wire that would be dead straight, not coiled.

 

John Isherwood.

[Dave John]

I have managed to solder spring steel wire effectively using bakers fluid and a proper 60/40 solder. 

 

The wire needs to be well cleaned with emery then some ipa or similar since the surface tends to be  bit oily when new. 

[cctransuk]

2 minutes ago, Dave John said:

I have managed to solder spring steel wire effectively using bakers fluid and a proper 60/40 solder. 

 

The wire needs to be well cleaned with emery then some ipa or similar since the surface tends to be  bit oily when new. 

 

Thanks for that - very helpful.

 

Regards,

John Isherwood.