Pipe Thread Sealant?

[pluikens]

@pluikens is this the Bill Wann video where you got the info about using silicone?

Yes it is!

 

[pluikens]

I think silicone on plumbing is a terrible idea. Just buy the products that are designed for use on plumbing.

Like DAP, GE, and Fuller silicone products designed for plumbing? Except, OP, don't use the bath stuff as it may have mildew resistance chemicals which you don't want.

 

[EdsReefOdyssey]

Yes it is!

I wish BRS would have included the Q&A at the end.

 

[Ocelaris]

What's wrong with teflon tape (the generic kind) on plastic? I've used that for years without issue on the house, on the sprinkler system, boiler piping, aquarium, you name it. Cheap stuff from harbor freight (10 pack) lasts forever. Otherwise if I have something hard to seal I'll pull out the blue monster which will stop anything. But for plastic thread, you shouldn't really have to crank stuff down, I use teflon as a fail safe, but really shouldn't be that big a deal as we're not really dealing with high pressure here. I think the trick is to use egregious amounts of tape if you don't get it to seal. The only problems I've ever had were with non-standard compression seals, like my JBJ chiller or the uniseal bulkheads. If you crank plastic down too much, it becomes impossible to seal. So be careful to not over tighten plastic, as I've cracked more plastic PVC over tightening it than I have had leaks. Metal on the other hand crank it down. Here's some shots of some other plumbing projects, because it's Friday.

 

[pluikens]

I think we have the topic for the least popular BRStv Investigates video. "We made five different threaded PVC connections, are recirculating water via Reeflo pumps, hooked up some LDKs to three different Apex units, and we'll check back in a year to discuss the results!"

But really...

I use Oatey joint compound paste with Teflon...

https://www.amazon.com/Oatey-31230-Joint-Compound-fl-Ounce/dp/B000KKVWL6

I think if you're using two different products for one task, neither is probably the right product.

I think the trick is to use egregious amounts of tape if you don't get it to seal.

I agree with wanting a good seal. Unlike slip fittings where the primer should be able to secure the pieces together and the glue is to fill any and all voids between the pieces, the feature of NPT threads being tapered means that if you tighten it down just enough, friction will keep the pieces from unscrewing on their own. The material used in between them should be to seal any and all voids between the two pieces. I think you'll agree with this based on wanting to use egregious amounts of tape. If we're looking to keep water from seeping between the two pieces of PVC, I don't know of a better product than a bead of silicone sealant around the threads.

 

[Water Dog]

I think if you're using two different products for one task, neither is probably the right product.

Huh!?! As far as I know, my recommendation of Oatey “Great White” pipe joint compound paste with Teflon is one product, not two. I’ve used this for all of my plastic threaded fittings from my calcium reactor to my tank plumbing with much success.

 

[pluikens]

[QUOTE="pluikens, post: 4824331, member: 87781”]
I think if you're using two different products for one task, neither is probably the right product.

Huh!?! As far as I know, my recommendation of Oatey “Great White” pipe joint compound paste with Teflon is one product, not two. I’ve used this for all of my plastic threaded fittings from my calcium reactor to my tank plumbing with much success.

[/QUOTE]My apologies. I did not visit the link and assumed you were using joint compound as well as Teflon tape.

 

[Reef of Fillory]

I use the Oatey pipe joint compound stuff too, never had a leak or an issue

 

[Fin]

I keep seeing where it is stated that teflon tape is not for PVC fittings. Personally, I have used it for more than 30 years with no issue. So, with a little research, I turned up this video from Spears Manufacturing, maker of some of the higher quality PVC valves, etc. Interesting short video, which I would consider to be about as reliable as you can get ...

 

[User1]

I use Oatey joint compound paste with Teflon...

https://www.amazon.com/Oatey-31230-Joint-Compound-fl-Ounce/dp/B000KKVWL6

Both? That is the first time I've heard of that. I used to only use Teflon but one day someone recommended Oatey's and I've never gone back. Messy product but nothing one can't clean up. Zero leaks or drips. Oatey or bust.

 

[Water Dog]

Both? That is the first time I've heard of that. I used to only use Teflon but one day someone recommended Oatey's and I've never gone back. Messy product but nothing one can't clean up. Zero leaks or drips. Oatey or bust.

No, not both. Again, Oatey Great White is a paste with Teflon in it.

 

[EdsReefOdyssey]

I think we have the topic for the least popular BRStv Investigates video. "We made five different threaded PVC connections, are recirculating water via Reeflo pumps, hooked up some LDKs to three different Apex units, and we'll check back in a year to discuss the results!"

I would watch that video!! ;)

 

[EdsReefOdyssey]

Ok, heres a video saying not to use teflon tape on PVC. :confused: I guess its like everything else in this hobby, use whatever works best for you.

 

[Picesduh]

Is the Oatey stuff still allow one to remove the fitting or it is permanent like Solvent is for slip PVC? Part of the reason I chose Threaded fitting at certain locations is bc I can make changes to it later.

Edit: Amazon Q@A answered this question - yes it’s removable (not permanent)

 

[Sleepydoc]

Teflon tape can work, (I’ve seen people make it work without anything, too) but most people (and the majority of manufacturers I’ve seen) recommend non- hardening thread sealant. The Oatey product mentioned above is one. I got a tube of Rectorseal T plus from Home Depot that works well. A small amount on the distal male threads is quick and much more reliable than Teflon tape IME.

Silicone can work, but it makes it harder to remove the fittings and harder to reuse them later on.

Somewhere I read a nice explanation why Sealant is better. I can’t find it now but basically tape tends to bunch up more, increasing the strain on the fitting and making it more prone to cracking. FWIW, Lasco recommends against tape...

 

[Sleepydoc]

Found some references; still couldn't find the site that had nice pictures explaining what happens with tape.

From the spears site (http://www.spearsmfg.com/IP-4/06 Installation.pdf): "Threaded connections require the application of a thread sealant....If PTFE tape must be used, Spears® recommends a thickness of at least.0025..."
Another reference from Spears: http://www.spearsmfg.com/how_to/FG-3B-0105_0706_English.pdf

 

[theMeat]

Silicone does not bond to plastic. Using it seams like a good idea but it’s not.
It goes against the three most important things when working with plastic threads. Don’t over tighten, don’t use something that hardens over time, and don’t over tighten. You don’t use something that acts as a lubricant because you don’t want to over tighten.
Don’t use compounds designed for metal pipe. Such as Teflon tape, Teflon paste, hemp, dope, or putty.
Do use a sealant. One for plastic
Did I mention don’t over tighten?

 

[CreatiVe2]

if I were to use the PLASTO-JOINT STIK for a submersible application in my tank, would it "leach" chemicals?
It would be a very small amount, just to secure two 1" bulkheads.

 

[joec]

I do not think I would use it submerged exposed to tank water. It does not harden so it might leach into water

 

[topjimmy]

They sell pipe dope for potable water @ home depot. Comes in a little yellow tube.