[sdiy] Solder stops flowing all of a sudden?

[cheater00 .]

On Wed, Jan 22, 2014 at 8:01 AM, Elby Designs
<elby_designs at ozemail.com.au> wrote:
> If you are using lead-free solder then you need lead-free soldering tips.
> They ARE different to lead tips and neither work well with the other i.e.
> lead-free tip and lead-solder or lead-tip and lead-free solder do not work
> well together.
>
> Also, lead-free tips need to run hotter than their lead counterparts.
>
> Cleaning and maintenance of the tips is completely different as well

This has not been my experience at all. What issues have you noticed?
What is the technical difference between the tips that you have come
across?

Cheers,
D.