the idea isnt bad, but there are some things to consider:
1.) Acetone forms some byproducts when it comes into contact with acids or bases - so you´ve to choose another solvent. I Think IPA would be nice.... also the acetone may react with your methylamine.
2) solvent ans gases must be absolutely dry! dry methylamine-gas with KOH, and HCl with conc. H2SO4.
good luck
please post you results!