I would not agree to the statement that it won't work with lead free solder.
You should use a soldering station anyhow for the multilayer boards and with a good alloy there is no problem.
I'm using Stannol HS10 Sn95,5Ag3,8Cu0,7 which is so far the best lead free solder I used and I tried quite a few.
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If you use a low cost alloy without silver it makes things more complicated.
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KR
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Dirk
Dirk