Hope, I think part of your problem is the base on which you are
soldering. An iron plate seems to me like a terrible heat sink (that
is, it will suck away a lot of heat and/or cause the piece you’re
soldering to be unevenly heated. You should be able to buy (by
mail), not too expensively, one of those soldering boards and/or one
of those fluffy firebricks (see your catalogs). Or, go to a builder’s
supply place and ask for a few fire bricks (I last paid 75 cents
apiece for some). They are not fluffy and can be heat sinks, too, but
I think once they’re heated up, they also disperse heat more evenly.
Eeek – from a didactic point of view, your class sounds awful,
although I agree that one must go with what one has. I used nothing
but a propane hardware store torch for years. Now I use
acetylene-air (easier to handle than the propane tank, also hotter,
but I don’t use my oxy-acetylene unless casting).
someone did say NOT to use base metals as practice ad I wondered why.
There are people who simply do not like base metals as jewelry
metals. I love them and so do my customers. But we all have our
"attitudes"-- I do not care for aluminum or pewter,and refuse to use
plated metals of any kind. C’est la vie!
As for stick solder versus paillons of solder, it depends on what
you’re making. Learn to use both.