After http://www.soliforum.com/topic/2350/abs-glue/ discussion about MEK and acetone,
I was wondering if model cement(MEK) is better at melting ABS or acetone.
I went out to homedepot to purchase MEK(substitute) and Acetone, and I throw in lacquer into this test just for fun.
I use lacquer thinner quiet often to clean sticker's glue from any object, metal glass or plastic, it melts plastic but not in an alarming rate... and the test have interesting result.

MEKhttp://en.wikipedia.org/wiki/Methyl_ethyl_ketone( aka model cement or butanone) melts abs, it does not melt plastic nail brush, so its very similar to acetone. MEK substitue is the only version of MEK they sell at homedepot labeled "similar to MEK". it is suppose to be less toxic... good to know (it's two dollars more than acetone)

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RESULT!
Acetone will melt ABS, to something really fine... if you let it sit, it will seperate from acetone and sink to the bottom.( I am using octave filament.) *it melts faster than MEK

MEK substitute melts ABS very well! it's slower than acetone but it still melts pretty fast, and very even. it doesn't sink to the bottom after melting.  if you ever build a model kit using model cement, you know it melts the plastic and welt the join, so.. overhand fell off? don't worry, just glue it back.  it's sooo much better than using acetoen glue to glue.  However it's not ideal for heat bed.  Acetone will evaporate on heated bed. MEK's reaction to heat is not that extreme, so it takes some time to "dry", about a min or 2 to dry.

Lacquer... after sitting in that bottle for 3 weeks, finally shows sign of melting, didn't know lacquer can melt ABS... at snail pace.