Homebrew PCBs

Hi all .. just some generic questions .. 
If they have been asked already .. apologies.

I use the iron on method for now.
Flat on the workpiece for a couple minutes followed by 4 - 5
minutes of "roller heat" . Where I roll the board
on a dowel using the iron .. 

1.   Heat and pressure is the method of course.
I am assuming I would have to change the time
for different thickness boards ? I have some .031
boards .. very tough to get to work. Which is why
I am asking mostly.

2.  When rubbing the paper off .. is it better to
soak the board in warm soapy water versus cold water?
I was thinking that  perhaps the soap would be a
wetting / release agent to some small degree and 
warm water a catalyst ?

3.  Effects of too much heat ?  does it actually
do something to the toner such that it in this
state causes it to not stick as well ?? 
So .. there can be too little OR too much heat that
can cause similar issues?

Thanks .. 

Randy - N2CUA

Most boards are coming out fine ..
Just fine tuning .. :)