Well, there was a great deal of attention paid to converting THCA to plain old THC, with heat. This process occurs over time all by itself BTW. Not completely, but continuously through the life of the harvested weed.
I've made tinctures where I did heat the weed up before putting it in the Everclear for a soak. I have also tried it without heating it at all, and I have to tell you, that it works way better, at least for me and my MS, when I ingest as much THCA as I can - meaning don't heat the bud.
I do all the "usual " things, grind whole bud (no leaf, no keif) in a blender, mix with Everclear, put in freezer for a week and shake a few times a day.
Then I strain it using a regular kitchen strainer, and press the hell out of the wet wad of weed, to squeeze out the last drop. After that, I strain it through a coffee filter, held by a kitchen strainer, and again squeeze it to death. I usually lose a couple of cc's to evaporation and the wad of weed. Some people save the wad, wrap it in a cloth, put in a sealed jar, and rub it on sore muscles. Haven't tried that, but I know if you get too much of the solution on your hands, you will get a buzz, so it probably works.
I pour the mixture into a glass measuring cup, and note how many cc's I have. Put the open container in a safe, dark, airy place until it is reduced by at least half - more if you have the time and patience. Now during this time period, some of the THCA is being converted to THC, but a good deal of it, is staying THCA, which is thought to have pain-relieving, neuro-protective and anti-inflammatory effects. I then pour it into a dark colored glass bottle with a dropper (available online) and store it in the fridge.
I usually don't get more than a bit buzzed, but move incredibly better and hurt a whole lot less. Which is exactly what I'm after. I have learned that buzzed doesn't always equal feeling better. I can vape the exact same weed as I've made tincture with, and some things actually hurt MORE, than when I use the tincture. I'm buzzed, but having weird aches where I don't even hurt on a regular day! Weird.
I've never been able to reduce the volume of tincture enough to have a concentration that I could put drops under my tongue. It's too gross, by the time you get it strong enough. That's why I put it in coffee. Still tastes yucky, but not impossible to ingest.
This method uses a whole lot more bud than vaping, but works better for me from a medical standpoint, without the bother of being impaired. It is easier to dose consistently, and more discrete. I just put 1.5cc's ( which I have calculated to have about 0.5 gram of bud in it) into my coffee and either have toast with butter (for the fat) or 2 cookies to carry it around my body.
It last 3-4 hours and then it's time for more coffee!
If anyone wants the "recipe" from start to finish, let me know.
Carry on buds!