On Sun, 30 Jul 2006 23:45:07 -0700, The Radio Amateur Formerly Known As
G4KFK wrote:


Steve wrote:
I thought it was the other way round - leaded solder is ok with all
component types but lead free solder shouldn't be used with components
where the leads have lead in the plating. All the manufacturers I've
checked with say leaded solder is ok with RoHS compliant parts.

From a compliance point of view, you can't mix either type, either way
around. If you use leaded solder to assemble (or repair) an RoHS
compliant device, it won't be RoHS compliant.

Yes - I meant my comment only about the metallurgy of the joint. As I
understand it, private individuals aren't expected to abide by RoHS and it
won't be applied to personal (as opposed to business) sales.

Steve

Wel,, it depends on which Pb-Free alloy is chosen. There is no
industry-agreed standard composition.

In general there are two competing systems:

Tin-Silver (Sn-Ag) and Tin-Bismith (Sn-Bi).

If Sn-Ag is used, then mixing standard Lead-Tin (Pb-Sn)with it is OK.
If Sn-Bi is used, however, there is a low-melting ternary Pb-Sn-Bi compound
that can cause you problems. Not all electronic component manufacturers
have decided against Sn-Bi (it costs less than Sn-Ag).

So the key is determining you have Sn-Ag solder on your Pb-Free component
(or in some cases, no solder on the component).

Roger


"Steve" wrote in message
news
On Sun, 30 Jul 2006 23:45:07 -0700, The Radio Amateur Formerly Known As
G4KFK wrote:


Steve wrote:
I thought it was the other way round - leaded solder is ok with all
component types but lead free solder shouldn't be used with components
where the leads have lead in the plating. All the manufacturers I've
checked with say leaded solder is ok with RoHS compliant parts.

From a compliance point of view, you can't mix either type, either way
around. If you use leaded solder to assemble (or repair) an RoHS
compliant device, it won't be RoHS compliant.

Yes - I meant my comment only about the metallurgy of the joint. As I
understand it, private individuals aren't expected to abide by RoHS and it
won't be applied to personal (as opposed to business) sales.

Steve

On Mon, 31 Jul 2006 07:34:50 -0500, Roger wrote:

Wel,, it depends on which Pb-Free alloy is chosen. There is no
industry-agreed standard composition.

In general there are two competing systems:

Tin-Silver (Sn-Ag) and Tin-Bismith (Sn-Bi).

If Sn-Ag is used, then mixing standard Lead-Tin (Pb-Sn)with it is OK.
If Sn-Bi is used, however, there is a low-melting ternary Pb-Sn-Bi compound
that can cause you problems. Not all electronic component manufacturers
have decided against Sn-Bi (it costs less than Sn-Ag).

So the key is determining you have Sn-Ag solder on your Pb-Free component
(or in some cases, no solder on the component).
Thanks for that - I haven't encountered anything with Bismuth yet. Plain
tin plating seems most common amongst what I handle.

Steve