I partake for discovery's sake but..
The DMT smoke is not entirely pleasant. Analogous to melted plastic.
Harsh to the nth degree, and makes me cough like non other.
Can't really see it becoming an acquired taste.

I use standard glass vap pipe, and obtain via STB extract tek with a defat + freeze precip.
Could it be an issue of purity?
Any suggestions on easing the intake?
Anything I could add?
Would Water vapor or various herb additions help?
or a different smoking receptacle?

Stop burning it, that should help.

If you are smoking just the DMT crystals, then you are burning it; hence the harsh smoke. I'm also assuming that by "standard glass vap pipe" you mean a glass stem with a bowl at the end. "Crack pipe." If I am correct in that assumption, you should really find a new way to ingest DMT.

Try putting it on a bed of caapi leaf in a water pipe.
The Glass Vapor Genie is very popular around here.
The machine is a cheap alternative.
There are numerous alternatives if you search the Wiki.

That may be it..
so is the harshness simply due to the fact that its to hot, or does the overheating/burning change the dmt in some way?

Burning destroys it and the crack/meth pipes suck imo

TOOL AND TEMPERATURE. Nothing beats the GVG + copper mesh + torch lighter combo so far, the vapor is very smooth at right temperature.

I am tired of people and even wikipedia mentioning how the vapor is harsh, it's all simply due to applying too much heat with a wrong vaporizing tool... Oh well whatever at least many nexians get it right

I appreciate the clearing of my ignorance on this subject. Thought I was doing something wrong
Definitely will try the machine/steel wool/ bottle method.

But also as a random somewhat unnecessary side thought..to utterly avoid said burning... suppose I heated DMT with a variable control hot plate to say 10 or 20 deg C (maybe more?) above the Boiling Point (would have to do some analysis do get an estimate for particular sample), in some sort container (glass test tube or low profile covered dish), then inhaled through connecting tube. feasible or superfluous?

One word : Mullein

What he said. Even in the GVG, I find the DMT freebase vapor to be harsh. I infuse some mullein with freebase and load it into my GVG. It's the magic of mullein. I had honestly lost hope until I purchased mullein. I was gagging on the vapor and on top of that I couldn't keep it down.

In my opinion the vapor is very smooth(and easy to keep down) from the GVG and I'm not a smoker. So maybe you just have more sensitive lungs, slightly impure spice or you apply too much heat when vaping(it doesn't require much heat to vaporize(I use torch lighter's tip at about 1-3 cm above bowl)). I would try mullein if I'd see it necessary but to me I see it as only more vapor entering my lungs which isn't a good thing IMO.

okey dokey i got a lil trick for reducing harshness, its called the mouth bong, you sip some water before smoke leave a comfortable amount in your mouth and as you inhale the water in your mouth will cool the smoke significantly making it smoother, this tecnique is prefered for spice as you dont want to cool the smoke too early or it will recrystalize in your bong/vape device, but this way it has no oppurtunity to recrystalise, its just nice ans smooth for sensitive lungs...if its harsh your probaly making it too hot anyways....but the mouth bong will help nonetheless

Any recommendations for a solid online Mullein source?

I don't think that temperature is the whole story. I used to, but I really don't think that's the case so much because when I vape harmalas out of the GVG, I can apply more heat and take bigger hits than with DMT and its still ridiculously smoother. DMT heated up to temperatures much less is incredibly more harsh. I think there most certainly is a factor about DMT that makes it harsh. I think harshness is also partially subjective so perhaps your throat/lungs/nervous system just tolerates it more easily than others as it is regardless of temperature.

Sure it's maybe harsher than other substances, but this is talking about correct vaporizing temperature.
Of course if one adds more heat even with the GVG the vapor will become noticeably harsher, anyone who's kept the flame too close knows it(me included), while when I keep the flame at proper distance I can barely feel the vapor, but if I add too much heat I won't be able to keep it down at all. So obviously temperature and tool are the keys to minimize the harshness. If some people feel it's still harsh even at correct temperature, that's another story...
I have also noticed how completely white DMT is slightly smoother than orange or deep yellow DMT.

Phat Platypus, you should also look into the Inspirator MKII from amorfati since it uses similar convection-based heating with buffer like a GVG, it might be a good way to vaporize DMT and you can make yourself for quite cheap.

Personally I have the GVG and like tele I highly recommend it, but you need to have some money for the purchase (it's certainly worth it though! ). If I didnt, I would probably go for inspirator mkII.

As for hot plate and DMT, yes in theory you could make something, but maybe you'll find your design is not effective, so that's one thing. The other, is that for some reason DMT's boiling point isnt really known, as funny as it sounds... Some places in literature mention 60-80c but that is certainly wrong, as even shulgin commented. But he didnt say which are the right values, and neither did anybody else publish the BP values in normal atmospheric pressure AFAIK. Benz mentioned it was calculated to be 320c I think, which sounds quite high but could be... One thing different experiments in the Nexus seemed to show, is that it's over 100c for sure.

i agree with mullein, even in gvg pure dmt can get little harsh with big rips, and mullein smooths over the edges very nicely, theres hundreds of places u can buy online like ebay, but u can also prob find at ur local natural health store