True but the main problem with cartos is when they begin to dry up and people keep using them they get so hot they melt the batting material. I have pulled enough apart to see that the batting is a giant black hole next to the coil. I do understand the carbonizing, that is where burn offs help, but with a carto you will melt the batting material, unless it is made of fire wick
Exibit A:
A step by step on making a carto from scratch out of a pill fob.
First drill 1/4" holes in both the top and bottom as such:
Now you can insert you choice of blank cart in the top one:
Next measure out your 36ga nichrome, solder the ends, and take 4 strands of silica fire wick and wrap your coil, I use a needle and medical clamps to hold it.
Now get an old carto connector and solder the ends to it, then push on a silicon tube and leave 1/8" clearance from the coil. In this picture I wrapped the coil with silica wick as a test to see if it keeps the batting from melting.
Insert new coil assembly into the bottom of the pill fob and press connector into place.
I used an old 801 atty to sheild the coil assy from the batting I was inserting:
Now I actually used silica fire wick material to see how this hols up, it is the loose strand kind, defeated the purpose of wraping the coil (I Know

)
Trim:
And tuck the remainder in:
Now remove the 801 atty and lightly position the surrounding material down and close to the coil assy:
Fill.... (This held 5ml of liquid!) and put the top on:
Connect the battery:
Vape your heart out!
Well I hope this inspires some folks to try somthing different. Will report back on the taste of this, and how the silica material holds up.
Dan