Best way to clean new PE parts?

PE is generally clean when it leaves the manufacturer.   They have to wash it and rinse all the etching residue off or it would continue to etch in the packet.

The problem is you and your pizza-grease stained fingers ...

I've found that a brief soak in lacquer thinner esaily dissolves finger oils.  After the lacquer thinner allow the piece to air dry on a piece of lint-free material.    It is then ready for painting.    

I have not found it necessary to anneal the PE by heating it to cherry-red over a candle.   I seem to be able to work it without that step -- perhaps on larger armor subjects it may be beneficial.   Anneal first then clean & paint.

I have tried an overnight soak in vinegar.   There was no appreciable difference in paint adherance between the lacquer thinner treatment and the vinegar treatment

EdGrune wrote:

PE is generally clean when it leaves the manufacturer.   They have to wash it and rinse all the etching residue off or it would continue to etch in the packet. The problem is you and your pizza-grease stained fingers ... I've found that a brief soak in lacquer thinner esaily dissolves finger oils.  After the lacquer thinner allow the piece to air dry on a piece of lint-free material.    It is then ready for painting.     I have not found it necessary to anneal the PE by heating it to cherry-red over a candle.   I seem to be able to work it without that step -- perhaps on larger armor subjects it may be beneficial.   Anneal first then clean & paint. I have tried an overnight soak in vinegar.   There was no appreciable difference in paint adherance between the lacquer thinner treatment and the vinegar treatment

The instructions which accompanied some of the White Ensign [and GMM ?] sets would have you heat the PE over a candle or stove flame until the piece was a dull-cherry red.   [Typical personal protection measures apply]  Take care to not heat to burning or melting as you do not damage fine etchings, such as railings or PE gun barrels.  Allow the piece to cool - do not quench the part in water to force cooling.  This process would change the hardness of the metal and allow it to be formed more easily.

I just went & checked some current instructions and I do not find these instructions.  Perhaps the advances in the drafting and etching technologies with respect to relief etching to provide bend lines has made this step no longer necessary.

EdGrune wrote:

Allow the piece to cool - do not quench the part in water to force cooling.  This process would change the hardness of the metal and allow it to be formed more easily.

Actually quenching cuprous alloys does not have a negative effect on annealing. In fact it's a better to quench cuprous alloys in warm water as it gives a more even cooling than air, especially where there are rapid changes in thickness. You're thinking of steels where quenching will harden it.

As for cleaning, I rarely bother with "fresh" PE since both Alclad and Mr. Surfacer adhere well enough. Older PE that has oxizied might get a buff from a microscratch brush or a quick soak in vinegar then a thorough rinse. If I'm worried about finger oil a quick wipre or dip of acetone works well.