Which material to use on Tank Mod's outer shell/tube?

[Snowball]

I've looked around but couldn't find anything definitive on the subject. I've built a few mods and am now looking into building a rebuildable tank/atty combo, something a little more "sophisticated" than the Big Daddy tanks (don't like how you need to use a carto -- never liked them, don't want to build a tank around them) -- you know, along the lines of Scubabatdan's tanks, Genesis/Zenesis, etc.

I want to be able to use some sort of transparent material but looking around on ECF (or Big Daddy Vapor's page on the tanks) there seems to be some concern regarding the use of polycarbonate with (some) e-liquids. Well, at least to the point where people feel the need to put up disclaimers, which is never a good sign.

So, polycarbonate seems to be off the list. Browsing mcmaster.com I found several polymers that seem to do the same job as polycarbonate (there's even a thread here where someone used a short length of polypropylene tubing) and yet are reported to be safe to use with water (for drinking purposes) and food -- though this doesn't necessarily clears them for e-liquids (even Tupperware uses polycarbonate for some products).

To make it short: one of the designs I was considering would have me tool threads into the polymer tube so I can screw the tube to the end caps (compressing an o-ring in the process for added water-tightness -- an idea I got from my PC's watercooling reservoir) so I started thinking about acrylic (more likely extruded acrylic) since it seems it would do the trick just nicely -- though I still need to look into the whole alcohol on acrylics thing (need to make sure my e-liquids are alcohol free).

Anyway, does anyone have any thoughts on this? Any info or tips from any of you pros would be appreciated.

 

[Sicarius]

Depends on the size of tubing. My favorite tank mod (use it every day) is made from 'vinyl' tubing. The kind you would use on say liquid cooling in a PC. Pic below.



Another material I used is the inner of one of those flexible stainless steel water pipes. Real tough stuff and reasonably rigid. Diameter might be a problem though.

 

[Snowball]

Thanks for the reply, Sicarius.. I'm very familiar with the kind of vinyl tubing you mention, but they are by no means rigid enough for the tank mod I'd like to build -- not to mention that you'd have a real hard time trying to drill/tool threads onto vinyl. They can be rigid on shorter lengths, and there's different types of vinyl tubing out there, some softer, some a bit more robust (ie, harder to bend) but I'd rather go with a material that's really sturdy.. Basically, something very close to polycarbonate but without the nuisance of the possibility of leeching that polycarbonate apparently has.

Thanks again for the reply and please feel free to share any other tip you might have.

 

[johnlacie]

Have you considered using a syringe tube?

 

[donnah]

I bought polycarbonate tuding on amazon and cut it to length with a band saw.

 

[alex3x]

Vynil tubing is a good idea for what I want to do...

But do you have a idea of wich material disponible in a hardware that I can use for the two endcap of the vynil tube?

tanks

Alex

 

[my4jewels]

I'm not a pro, but I have heard that acrylic was what was used before polycarbonate. It was discontinued because it was so fragile and brittle. I'm the one who used the polypropylene tubing with the liquinator endcaps. I am comfortable vaping with this material, and it is working out phenomemonally well.

 

[srolesen]

i'm not sure there's a clearcut answer. all polymers are sensitive to pressure, acrylic and nylon cracks when under pressure and exposed to acid, polycarbonate when under pressure and exposed to bases. and then there's the whole durability thing, if your plastic is too soft the endcaps wont be a snug fit for long, and it'll scuff easily, if it's too hard it becomes brittle, and more prone to stress cracking.

i figured the right strategy might be to not put it under pressure, or atleast minimizing the pressure and thereby solve the liquid compatibility problem from a design angle, instead of a materials one
i have a feeling that a good deal of polycarbonate cracks are actually not polycarbonate tanks, but acrylic ones, and then there may be polycarbonate tanks cracking from endplugs expanding instead of the polycarbonate itself actually cracking from incompatibility to the eliquid. so i made this test with acrylic->
http://www.e-cigarette-forum.com/forum/tank-mods/267503-welded-acrylic-tank.html
the idea was that acrylic was the most vulnerable material to stress cracking so i did eliquid test on it, strong coke flavour cracked the end towards the battery in about 10 minutes, even tho there was about 10mm of materiel the grommet had to pressure through to make crack propagate, the other end where there was no grommet is perfectly fine here 5 day's after i made test.
so i'm thinking welded polycarbonate tanks might be compatible with everything, if ends are made with weld instead of grommet, sorry if this doesnt answer original question

 

[notsmoking]

What did you use to weld the material to itself? I like the looks and if it works.... I would like to try it. Thanks

 

[srolesen]

i reply in thread about acrylic (or polycarbonate) welding so as to not hijack this one for plastic welding

 

[donnah]

I'm looking into syringes for the syringe tanks. I've heard good things about them, actually I've not read anything bad. Someone sent me a couple and they look pretty sturdy. I haven't tried them yet because I'm waiting for the screws that I ordered to come in. I like fill holes in my tanks.
I found a pretty great deal on what looks like the type of syringe (and plunger) that is needed for making the syringe mod. The 20 cc syringe is .55 each and free shipping. First I'm going to check out my local tractor supply to see what they have.

Just thought I'd pass this along.