C(r)ooks instructions:
Add concentrated HCl to freebase with stirring until pH = or <3. Take your time. This gets hot. If pH paper or meter impaired just add until color changes and doesn’t change back then add a dash more.
Add at least 9x that volume of toluene.
Distill off toluene and water until the still head temp is that of pure toluene or just boil until the flask clears then remove from heat. Decant into another vessel to facilitate crystal removal if you want.
Filter beautiful crystals after cooling.

Big kid’s department:
This method really is as easy as it reads. The only thing to keep in mind is that you need a lot of toluene because first you need it to azeotropically distill off the water(80:20) and second you need a sufficient volume to keep your crystals swimming after formation so you can recover them with sufficient solvent to hold impurities. With gassing one can stop when needed to filter and/or add solvent. With this it all comes at once so you better have enough. If you make a puck it will trap what you don't want.
Even with more sensitive freebase, one could add dilute HCl till the proper pH or without equipment add dilute HCl to freebase until you only have one layer plus a dash more then distill from there, possibly needing to sep funnel your distillate and add your toluene back to the pot to get all the water.
This can also be run under vacuum if lower temps are needed.
This whole tech could be run without a single thermometer, test strip or piece of glass if you were paying attention to visual clues. Disposable stirbar loves the lazy man's way, especially when it is the right way.
Unpleasant gassing rigs are now a thing of the past.

Someone take a swing at this and see. Super low effort home run every time.

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Bees make honey.
Popcorn says fuck you.

This works because of the toluene(or benzene, but who uses benzene?) water azeotrope drys this without any hassle or prep. UTFGoogle for "Dean Stark Toluene" and check out how amazing it is.

Gassing rigs and the use of alcohols require precautions to be taken against moisture. Drying agents for the solvents involved, fiddly dangerous bits for anhydrous HCl generation and/or gas drying. This requires none of that. It drys itself. It tells you when it's done. It is super simple and hard to mess up. Pretty much the only issue is knowing that solvents and their vapor are flammable and that you shouldn't breathe tol, unless you are a gasoline huffer, then do whatever.

pH 3 is for c(r)ooks. It is also because boiling anhydrous toluene doesn't seem to hold HCl very well or with the solvent volumes involved it seems to be very tolerant. One ends up with beautiful crystals. People who have successfully made substituted amphetamine or methamphetamine should know how far to go for their flavor and don't need me making a list. 3 gets it done for (MD)A&(MD)MA.

Should you recrystallize? Of course you should, but if you aren't going to do it anyway it might as well start off cleaner.

Garbage in, garbage out is a rule with all of these things. Distilled freebase and solvents make everything nicer.

If one titrates base you are cooking down and end up with a concentrated mess of whatever you started with, usually requiring tricks, drying agents and difficult to recycle solvent mixtures to get to crystallize.

Did I mention solvent recycling? In these days of battling for every ingredient it is nice to be using toluene. It evaporates comparatively slowly so you filter it more then you evaporate it. Toluene once washed a time or two with dH2O and fractionally distilled is good as new as long as you didn't do something stupid like mixing solvents.

The only faults I find with toluene are that it floats on water and sometimes with heavier oils and large reaction mixtures you want a "bottom puller" and also that it has a higher BP so it isn't as quick or low temp to strip from work-ups if need be.

This azeotropic drying really is pimp shit. Know all that careful ketone or freebase drying before distillation to eliminate water bumping? Standard neutralizing wash, saturated salt wash, drying agent, distill? If you are using tol as your solvent and distilling it off before distilling your product it does the drying for you, greatly simplifying the procedure and eliminating mechanical losses.

Try it. You'll like it.

EDIT->I forgot to mention that I will be putting this over at WetDreams Reloaded. I wanted to get the questions answered before throwing it to the peanut gallery

EDIT2->"Are there any benefits to titrating the freebase before it is in a solvent?" Yes, aqueous layers are where you read pH.

"Aren't crystals hard to achieve because mdx is a racemic mixture?" Hard to achieve with this tec or any of them with careful(dry) procedures? No. Hard to achieve big crystals? That depends on which salt you are making. This will not make shards from stuff that wont shard. If yours does form bigger crystals, then don't agitate/vibrate/torment it while cooling and enjoy the show.

You did see Quantum Dudes post regarding a similar technique?
http://127.0.0.1/talk/index.php/topic,713.0.html

Wow, this is really easy.  Great write up disposable!

The pants do not make you look fat.

Xylene can be swapped for Tolulene in this application. Pick your smell. 

The sudden appearance of the crystals in the solvent when the moisture is almost all gone is amazing. Continue distilling a little after the appearance of the crystals if you don't have the thermometer in your still head to assure you have all the moisture out of the solvent. The crystals will crash out before total dryness, but not that far from it.

I suggested this same thing a couple year ago over at WD. Yes its perfect. My suggestion was to gass then mist the Ether under heat until all your salt dissolves. Allow it to SLOWLY evaporate and it takes the H2O with it yeilding Glitter. Perfect freeform crystals.

"I swear to you all that I am not posting to fuck you up. "

I never had the idea that you were. I'm was just interested in having the discussion since your understanding doesn't agree completely with mine and I'd like to understand why. That's not at all to say that I don't believe you.

"Toluene(and benzene and xylene) are PFM! They do not hold any appreciable amount of water but carry a bunch in vapor."

It's been my understanding that toluene forms an azeotrope with water at some substantial percentage (10-20%?), where xylene forms one of only about 1%. However, I've seen MA boil out of xylene in amounts that seem too great to have been held by that little bit of water. I've never had a good explanation for that, but the idea of a solvent immiscible with water holding a significant amount in vapor is a new one on me. Or is that what's sometimes referred to as entrained water?

The procedure I'm familiar with is to steam distill the based post reaction mix into xylene, then use gas generated with CaCl and HCl, which I recognize is not as dry as might be desirable, then boil away the water/xylene azeotrope to claim the residual. It's probably not a fair comparison, but what comes out of the xylene is never as clean as what comes directly from gassing.

The technique sounds interesting, I admit. Would there be any reason that you couldn't add xylene before adding the acid? Since MA FB is rather volatile I'm thinking that to avoid losses it would be better not to handle it in the pure form. In the sub-tonnage ranges I'm thinking about, (significantly sub-kilo as well), I'd rather not put a drop of it on PH paper!

The need to separate isomers is yet only a dream.

Cheers,
PP

then boil away the water/xylene azeotrope to claim the residual.

No where do I say anything about going to dryness like that. I meant the solvent gets dry, as in no more water, not dry as in no more liquid. If a sufficient quantity of xylene was used to completely dry the salt and still have a little extra so you don't make a solid puck, then the crystals, salt in xylene, should be similar to gassing, the only difference being that the azeotroped ones should be more dry which should lead to an exclusion of some impurities, giving you cleaner dope.

This being an optimization thread and everything being a work in progress, I am continuing my reduction in required acid. The product comes out beautiful.

To take the pH of your base in xylene would be a real PITA. I have done it(with toluene) and it works, but you must dropper a bit from the bottom aq. layer. I tried turbo stirring in hopes that there would be enough microdropplets to effect a good test, but not so. That was the time I verified that one can just dump acid in wholesale and the thing will still work.

Is just dumping it in without testing pH the right or best way? No.

I am leaning toward the 6-5 range as being the guaranteed winner, even though the pH of aq MA salt is neutral to slightly acidic, the impurities present might mess with that. Perhaps the 7-6 is where you want to really be, but like hell if using 10,000 test strips and a million drops of HCl is fun. Get it close. MA is tough.

Dry acetone is almost required afterward because tol just doesn't want to go away and the smell sucks.

PP, those 'upper layer' / 'lower layer' designations relate to relate to the organic phase and the aqueous phase after the azeotropic distillate has separated. Xylene is a good solvent for getting rid of water; that's why all those patents use it to break the ethanol/water azeotrope.

And my handle is Enkidu - get it right 

2 silly question...
-to make the distillation of the toulene ,we need to add a stirbar to the flask,boiling stones,...or better without anything and let the toulene and water comes slowly?
-we have to see the crystalls formed on the flask ,or we have to transfer the toluene to a beaker when the soultion it´s clear and we are sure that water it´s all out (reading the still head temperature),and then  wait for crystal growing by slow cooling?