In my experience, “heat” in general is not a good factor for the purity (whiteness) of the final product, it may be something obvious for experienced extractors, but as a newbie i would like to describe my processes in learning.
Some people like it, some don't.
For me, it's more of a new acquaintance.

For both extractions i used a strain-cleaner, which contains mostly hexane along with a buch of other compounds.

Those are my experiences with heat and DMT extractions (Cyb's Hybrid ATB and Max Ion tek), hope to help somebody out, or to be helped by somebody, i will describe only the critical steps:

...added lye and let it dissolve, then immediately added room temperature solvent and closed the jar.

As soon as i started rolling the jar in my hands, i heard a loud fissing noise, probably due to the expansion of the solvent fumes (caused by the heat of the basic solution).

As the lid was opened to release the fumes, i got hit by drops of solvent and hot solution, good thing i was protected with glasses, gloves and lab coat.

Closed the lid and managed to proceed with my pulls:

The first pull was fluorescently yellow and incredibly saturated.

The colour of the solvent went less yellow as i performed the other pulls.

Evapped, freezed, results: super yellow goo, impossible to re-x, could have tried a mini A/B.

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On another extraction:

...managet to let the lye solution to drop about room temperature, and tried to extract with hot solvent.

Placed the solvent in a hot water bath and heated until 40 °C, then poured into solution and mixed well as usual.

This time, i wanted to try to evaporate the solvent instead of reducing volume and then freezing, or straight freezing.

So i grabbed my fan and waited.

As i went back, the solvent was evapped, leaving on the glass dish a thin white/transparent film (gooey/sticky, incredibly difficult to scrape off) and some crystals.

Tried to re-x the crystals and film, and then proceed to a freezing phase of about 24 hours.

The results where the same:

Even if freezed, the sticky-white goo returned, along with crystals, mini A/B necessary?

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So, theese are my experiences with heat and extractions, think i can hazard some simple hypotesis, based also on the readings i did on the Nexus:

1) Heat will draw more product, along with impurities.

2) Heat can be applied to solvent or solution with the same effects just mentioned.

3) Excessive heating the solution will cause solvent to expand (potentially dangerous) and to draw a lot of impurities, so many to probably require a further A/B step.

There could (and probably there are) many other factors that would need a further analysis, for example:

1) How much heat is too much?
2) What was the sticky film/goo?
3) Different solvents, different results?
4) Much more complex question who i can't think of due to lack of chemistry knowledge?

I think i may be able to help you out here.

Too much heat does pull a gunky product, as you have already learned. The remedy here is to add your lye solution slowly in small increments while stirring so the basic soup does not get hot too rapidly. 10-20ml every 10min works well for me.

Allow time for your jar to cool before adding solvent, heat bath the whole container until the glass feels warm to the touch. I like mine just as the point the bottom of the container starts to give that bite to the hand from heat. It is still not too hot to handle with ungloved hands at that point.

The clear film is always there for me. Or at least i have not been able to extract without it occuring yet. It seems usually to be very active, but using less heat along with precip in a pyrex dish vs a mason jar seems to minimize how much there is per pull. When using a baking dish for precip it allows you room to easily scrape the crystals from the clear gel without picking any up if you are delicate when scraping the crystal.

The gel/goo i am working on figuring out if is somthing that is normal or it happens from something i do during extraction. It seems that without it the crystal formations may not even stick to the tray. What i am doing is after scraping all the crystal i can, dissolving the remnants in my dish in vinegar & using that to wash solvent after pulls & then later collecting a the vinegar wash & using that to extract from to recover more DMT. I want to try & see if all that clear gel maybe forms actual crystals if the precipitation process is slowed down. 24hr room temp precip, followed by 24hr fridge precip & 24hr freeze. I believe it to be mostly DMT based on potency, it seems like maybe it just precips so quickly in sudden temperature change that it traps impurities & does not get the oppertunity to form a good crystal lattice, obviously it being under rather than on the crystals, the gel has precipped first.

I really don't get this part:

You have some residues in your dish, take the vinegar, dissolve them, store the vinegar + dissolved resiude somewhere.

Proceed to pulls, repeat the process of resiude + vinegar for every pull.

Once extraction is conclude, just pour all the vinegar you got into the solvent, let freeze, collect remainings?

It is simple. You are just using the vinegar to dissolve your goo, washing the solvent you collect after freeze precip with vinegar water, & then drawing off the solvent & proceeding with the remaining vinegar water if it was the acid boils from a new extraction. Much less lye is needed to base the second time around. It works out better to add the solvent wash vinegar solution with the tray wash so they both get worked on simeltaneously.

I have found 50C to be the point of diminishing returns for naphtha pulls*. Any hotter just creates more risk and makes for dirty pulls. I do this in a water bath (electric heat only) with the lid neither loose or tight but snug to avoid building pressure, and leaving at least an inch empty at the top so that only air and fumes are exhausted, just tighten enough to build maybe 0.1PSI relative/800Torr. And always put a couple layers of dish cloths down under your solution jars, or direct contact between the glass jars and metal/Teflon pan can cause them to break. I have had this happen before and it's a noxious cleanup that can damage cabinet finishes and all flooring surfaces barring tile.

When temperature is reached, I'll tighten the lid (for canning jars; rubber side down; and agitate. Loosen lids and return to water bath for a couple more cycles before removing the naptha. For canning jars, remove the lid, wipe down the rubber/coated side and replace metal side down. You want a good seal for the agitation, but leave the rubber/coated side in contact with solution for a minimum time.

I'll usually hold them at 50C for a minute or two to ensure heat penetration. Using this method, only a slight and brief puff of air and solvent vapor is released when opening the lids. There's nothing too dangerous, but still wear safety gear and loosen at arms length. If using canning jars, you can just install the rubber gasket upwards so that the "seal" is glass to metal. Just make sure you scrub down the top of your lid with the solvent being used so that any ink or varnish doesn't make it's way into the solution. This is a wise practice also in that the combination of NP solvent and 11+ pH can destroy both the rubber seal and the inner coating of the lid, introducing potentially harmful compounds into your spice. With stronger bases like lye, this degradation occurs very rapidly.

A more efficient and safe method to pull faster is to use more pervasive NP solvents likes xylene or DCM, evaporate and then clean up using smaller amounts of naphtha to re-x. Then the safety issue is venting the toxic fumes. In this case there is no need to apply heat except for in small amounts to accelerate evaporation.

Some day, when I have a proper glassware set up, I plan to drip DCM (more dense than water) through the basic solution into a heated triple neck RBF at 40-45C. The DCM fumes will travel up a column and a condenser for a continuous drip through the separatory funnel at 25-30C containing the basic solution. The third neck of the RBF will be for the thermometor and a p-trap air lock (3-4" H2O) will be at the top of the column. Once the pull is complete, the separatory funnel could be replaced with a collection flask and the third neck could be plugged to remove the DCM from the RBF and recycle into the collection flask.

I digress, but yes 50C seems to be the magic number (naphtha and probably heptane/hexane as well) for being both clean and efficient and not significantly more dangerous*. Compared to room temperature (23C), naptha seems to pull 25-35% more at 50C.

*It's kind of beating a dead horse, but never use any kind of flame or ignition source to heat flamable solvents such as any of the above mentioned. It could put many more lives than just your own at risk and possibly getting locked up on top of having your house burn down and the insurance company refusing to cover it. Even when using electric, make certain that there is no flammable material near the burner as this could auto ignite and cause catastrophe. I once had a close call trying to boil down acetone over a natural gas range. Luckily, I had been through some basic fire fighting training about a year and a half earlier and there was a wet rag handy that I could throw over the pan of flaming acetone. Even if using electric, I would highly advise having a couple large drenched towels nearby just in case as well as a large fire extinguisher (read the instructions).

If you've got the financial, you'll want to be looking at liquid-liquid extraction equipment. Works with heavier-than-water solvents as well as lighter-than-water.

I didn't read anybodys posts on this thread because well i really dont care lol. But if you want white dmt i think its best to avoid heat unless youre going to do a mini a/b. If you use heat your going to get yellow dmt and by the time youre done cleaning it you'll have the same amount of dmt as if you never used heat. Just my opinion...