TV, I'm sure you have...
And now you are here, giving suggestions...
Yes, an open air resistor, with no heat sink, will get hot enough to melt the solder, but when the resistor is in contact with the heat sink of a proper size, in a proper body, as in this design, the heat is kept below the temperatures needed to melt the solder we use.
So what's your point? Since you are not building a Pandora (you say so) and this happened to
you in
your design. We know nothing about you or your ability, but you come here... with what purpose? Sew the seeds for your new business? Here we go again.
If your suggestion, that the resistor would melt the solder, as it is used in this design, were a fact (it is not), then failures would be very common (they are not, the solder is intact in units I have pulled apart).
I wondered how long it would take you to pop up, TV. And now you are here making unfounded claims about our design.
Do you have a name and website or is this just an anonymous posting? C'mon out of the shadows, Trav.
So folks , if you are building a Pandora, just follow the manufacturers instructions. This fellow is well, you know...
This design (resistor and heat sink) and the use of this resistor has been around since 1978. If they were melting we would have known by now...
BTW drops of solder are reflective and stick to the wooden cavity during assembly. Has happened to me, more than once. Hard to see and they can get closed in and later fall free. I've shaved the leather off a few units and drilled a small hole to let the BB drop out, then glued leather back on. Now that I can see again and now that I have had this happen a few times, I inspect the cavity very well before glue-ing the bottom on.
And unrelated, the fuse blowing above seems car related not a Pandora issue as the unit is working fine and does not blow fuses during operation. A short will blow a fuse. This is blowing fuses when the ignition is switched off. Yet the unit works fine in the car and the house. Further troubleshooting with another car will tell us more.