I know the XL carto, stainless steel is made for use in tanks. Imagine made that comment a while back in another thread and I don't remember which one.
It appears that most folks that buy the XL SS Cartos do so to make APVs. I have played around with a few homemade tanks using the XL SS Cartos with varied success/failures using small lexan tubing. My conclusions are it is cheaper to buy these products than it is to make them although it was a very good learning experience. If you go to the DIY sub Forum under the "Tanks Topic" there are many designs you can make at home using the XL SS cartos with drawings and assembly instructions but I have plenty to do as it is and decided to just stick with my SI Clearos for now.
I watched a video the other day where a guy made a tank out of a 5ml plastic nicotine liquid bottle. No gaskets or seals at all and used nothing more complicated than a hammer to make the hole in the bottom of the bottle and a sheetrock screw to make a hole in the carto. If I had a 5ml bottle around I might give it a try for a laugh, I've got the cartos.
Incidentally, SI cartos are among the very best available so they would probably work out very well in an application like this.
I built three based on one of the drawings from the Modders - Tank Sub Forum, they all worked but call me lazy. I can buy Clearos for less money than the 4 hours of labor I put into the three and I had to go buy o-rings and I wish I had just taken out a Hammer and been done with it. When I first started Vaping I bought 20 of the XL SS Cartos before I watched Mr. Outlaws video on Clearos, so if you want a couple to experiment with I'll be happy to send them your way. 10 of them are still in the boxes.