Do I need food grade plumber's tape?

[Beer Viking]

I'm going to take another crack and assembling my mash tun. Do you know if regular plumbers tape is safe or do you use food grade plumber's tape?

 

[Ki-ri-n]

Do you mean Teflon tape? I've used it with no problems.
Don't even think there's a "food safe" version. But I could be wrong.

 

[Closet Fermenter]

I don’t think it’s an issue. The contact area would be so tiny that I can’t imagine it making that much of a difference. If the threads are machined well, there may not be any contact with the teflon at all! I’m just guessing here; would be open to a more informed opinion.

 

[Brew_Dude41]

PTFE tape is FDA approved, but there are different grades.

If you are using the standard white you should be fine.

Where are these threads located that you are using it on? If it is on the outside of the tun, say on a nippel joining the tun to a valve you are fine.

 

[PCABrewing]

Do you mean Teflon tape? I've used it with no problems.
Don't even think there's a "food safe" version. But I could be wrong.

PTFE tape is FDA approved, but there are different grades.

If you are using the standard white you should be fine.

Where are these threads located that you are using it on? If it is on the outside of the tun, say on a nippel joining the tun to a valve you are fine.

Yeah, it exists, PTFE tape cleared for food processing is 15+ times more than standard grade.
Search for "21 CFR 177.1550" and start reading.

 

[PCABrewing]

The purpose of PTFE tape is to provide lubrication to threads so that the fitting can be tightened enough to create a good mechanical seal.
The common use in the "wild" depends on the "filler" property of the tape to plug small channels but that is not the technical intent.
But with that in mind there is a cheaper option that should provide the required lubrication and is readily available.
I'm talking about Keg Seal lubricant.

If you can get the (NPT) fitting tight enough with that as a lubricant you should be good to go.
Challenge is the threads on stainless fittings are frequently a little rough due to the hardness and it doesn't conform like brass NPT does.
Hence the tendency to use PTFE tape as a "thread sealer".

 

[Deadalus]

I don’t think it’s an issue. The contact area would be so tiny that I can’t imagine it making that much of a difference. If the threads are machined well, there may not be any contact with the teflon at all! I’m just guessing here; would be open to a more informed opinion.

Fittings inside the tun and within the mash column can easily have their teflon tape exposed. The width of the wrap often exceeds the threads that end up inside the fitting, even if you don't move off the beginning of the threads when wrapping. The tape could be trimmed but I don't worry about it.

 

[RAmeeti]

Yeah, it exists, PTFE tape cleared for food processing is 15+ times more than standard grade.
Search for "21 CFR 177.1550" and start reading.

All PTFE tapes are food safe. But then too, they do have different abilities to seal a leak.

White - Single density (Water)
Yellow - Double density (Gas & Fuel)
Blue - Double density (Acids, Alcohol, Compressed Air)
Pink - Triple density (Larger threaded sizes of pipe, typically water)
Green - Oil & Grease free (Oxygen, Hospital)
Silver - High density impregnated with grains of Nickel (Stainless steel threaded end connections)

There are regulations requiring different types as well. Gas stations must typically use the Yellow for fuel lines, Hospitals must use the Green for Oxygen lines, etc.

 

[PCABrewing]

All PTFE tapes are food safe. But then too, they do have different abilities to seal a leak.

...

There are regulations requiring different types as well. Gas stations must typically use the Yellow for fuel lines, Hospitals must use the Green for Oxygen lines, etc.

And, operations that are covered by 21 CFR 177.1550 must use material "cleared" by FDA for that application.
The answer "All PTFE tapes are food safe" will not get you past the inspector. Just a point to be aware of should you ever land a job in food processing and production.
Fortunately most home brewers are not subject to that regulation.

 

[RAmeeti]

And, operations that are covered by 21 CFR 177.1550 must use material "cleared" by FDA for that application.
The answer "All PTFE tapes are food safe" will not get you past the inspector. Just a point to be aware of should you ever land a job in food processing and production.
Fortunately most home brewers are not subject to that regulation.

My point was that you do not have to buy the expensive speciality application colors to meet 21 CFR 177.1550 spec.
ie. https://tfcoinc.com/ makes several versions of the white (thinnest, cheapest color) that meet the spec for the FDA.

 

[Beer Viking]

Good to know guys thanks! Now is all white plumbers tape the same as PTFE tape?

 

[RAmeeti]

Good to know guys thanks! Now is all white plumbers tape the same as PTFE tape?

All PTFE tape is Teflon tape. Beyond that statement, you are on your own. The cheapest tapes on the market may not meet any particular standard regardless of color. It will be on you to determine the quality or spec of the particular tape on the shelf in front of you. Some white plumber's tape is crap, other inexpensive white tape meets the spec and is awesome. Know your supplier and quality that they sell.

 

[Beer Viking]

So I can assume that any PTFE tape is indeed food grade?

 

[Broken Crow]

So I can assume that any PTFE tape is indeed food grade?

Even the cheapest roll in the hardware store discount bin is non-reactive and can take 260°C so contamination is never gonna be an issue for the homebrewer. The absolute worse thing you don't really need to worry about is leaving a shaggy exposed part that may leave a few particles the first time you boil water in it, but even so; the particles will sink to the bottom and never contaminate your beer. It will not degrade or drop any more bits off and you can feel safe leaving it to your grandchildren in your will because it will outlive you and still perform just fine.

 

[PCABrewing]

So here is the funny part.
Depending on the store you walk into, and probably the age of the employee you talk to, if you ask for "Plumbers tape", you might get a roll of metal strapping with holes through it at uniform spacing.
And it isn't worth a darn for sealing threads.

 

[Brew_Dude41]

So here is the funny part.
Depending on the store you walk into, and probably the age of the employee you talk to, if you ask for "Plumbers tape", you might get a roll of metal strapping with holes through it at uniform spacing.
And it isn't worth a darn for sealing threads.

Or a roll of duct tape and a blank stare...

Might be interesting what you get asking for pipe dope.

 

[pcdiver]

I'm going to take another crack and assembling my mash tun. Do you know if regular plumbers tape is safe or do you use food grade plumber's tape?

I use regular white Teflon. I prefer the thicker blue plumbers Teflon but haven’t had access to it for some time.

 

[CascadesBrewer]

I checked the $0.98 per roll Harvey brand tape sold at Home Depot (https://www.homedepot.com/p/Harvey-...-Sealing-PTFE-Plumber-s-Tape-178503/202280370). The FAQ for that produce from the manufacturer says:

Q: Is Oatey White General Purpose thread seal tape safe to use on potable water lines?
A Yes. All Oatey thread sealant tapes are safe to use with potable (drinking) water.

 

[IslandLizard]

The absolute worse thing you don't really need to worry about is leaving a shaggy exposed part that may leave a few particles the first time you boil water in it

The remaining, exposed end of the teflon tape can probably be easily removed with a (small) stainless steel wire brush. I also clean teflon tape off male threads with one of those brushes. Works dandy.

 

[Beer Viking]

Thanks everyone that certainly helps! Also I've tried getting a good seal on my mashtun a couple times now and am still getting a bit of a leak. Should I use some sort of food grade silicone on top of the tape or just do it again with more teflon tape?

 

[Brew_Dude41]

The leak could be from the port it self. How is the mash tun ported? Welded port or a weldless fitting? Weldless can work themselves a bit loose or you can have the silicone seal turned the wrong way. One side is typically flat and should be facing the washer. the other side should be a small cone raised in the center and that should be facing the wall of the tun. Reverse that and you can have a hard time getting a seal.

Too much tape I am told can also cause leaks. 3 times round is what I have told been told in the past.

 

[IslandLizard]

Thanks everyone that certainly helps! Also I've tried getting a good seal on my mashtun a couple times now and am still getting a bit of a leak. Should I use some sort of food grade silicone on top of the tape or just do it again with more teflon tape?

Could you post a picture of that bulkhead area and point us to where you see drips?

My converted cooler mash tun needs a little silicone at the bulkhead area to make a perfect seal.

 

[IslandLizard]

Too much tape I am told can also cause leaks. 3 times round is what I have told been told in the past.

3 times around is just a (minimum) guideline. Most times I've resorted to a few extra windings and/or using thicker (yellow or gray) tape to create a seal. Much depends on the matching and machining of the threads, which isn't always perfect.

 

[Broken Crow]

Like @IslandLizard said: Please post a picture. If this is one of the Mash King cooler tuns that are the most commonly avaiable in Canada, there's a good chance the bulkhead came with flat washers and wants a ton of torque and will likey still leak anyway or seep internally between the inner and outer plastic. I've posted a few times about bulkheads and the need for an oring in a grooved locknut creating the seal on the inside of the vessel.. Here's one with pics: https://www.homebrewtalk.com/thread...system-for-cheap.680992/page-16#post-10364989
It covers teflon tape too.
Yes it's in the Fermonster thread, but the rules for bulkheads apply to pretty much all brewing vessels.

 

[CascadesBrewer]

Speaking of Bulkheads and leaks... @Bobby_M has a video at this page about bulkheads: https://www.brewhardware.com/category_s/1838.htm describing the same issues I had with the common threaded bulkheads. I am very happy with the "True Weldless Bulkhead" I got from him.

 

[Broken Crow]

Speaking of Bulkheads and leaks... @Bobby_M has a video at this page about bulkheads: https://www.brewhardware.com/category_s/1838.htm describing the same issues I had with the common threaded bulkheads. I am very happy with the "True Weldless Bulkhead" I got from him.

Totally agree! I was hoping @Beer Viking would post a picture or tell us more about the full setup so we might be able to recommend a few more parts since this is a new 3V rig being put together (https://www.homebrewtalk.com/thread...-propane-tank-to-it-and-turning-it-on.734397/)
Surprisingly, no-one has yet suggested BIAB as the simplest option for going AG yet.... I love Bobby's True Bulkeads! I've cobbled together so many coupler based ones and his fixed hex fitting alone solves the aggrivation of getting the right depth while simultaneously allowing you to orient your valve or diptube correctly, but there's more: No-one else anywhere has Bobby's false-bottoms for BIAB, (plus he carries the Wilser bags) his 3-way valves are all full-port and his Spin Cycle recirculation parts are better than anything else out there. As the OP is (like me, in Canada), there's a relatively high shipping cost + duty, BUT: As these parts are available no-where else on earth, it's worth the shipping and taxes which can be minimized by placing a large order. I can't recommend buying only the one True Bulkhead (Probably this one: https://www.brewhardware.com/product_p/truebulkheadmale.htm) because it would cost $46 CAD before duty, BUT; add several more items to that order and the shipping only goes up a dollar or two..makes it more efficient on the pocket.

 

[Beer Viking]

Here are the pictures guys. It's a mashtun and it only leaks a bit. Instead of trying to install the valve again I might just use food grade silicone. I'm not sure what to do.

 

[Deadalus]

@Beer Viking What does the back of the hex nut look like? Is it grooved? Is the oring flat or round cross section? The one Broken Crow linked is an excellent bulkhead. The groove holds the oring in place. I like to use a flat oring on some of my older bulkheads without the groove and a sometimes even a metal washer. The washer can help to keep the oring from spinning/twisting. But with the grooved hex nut, the washer isn't need between the hex nut and the oring. Plus round orings can be just fine.

If your sidewall hole is sized right, you shouldn't need silicone. I've got a dozen weldless bulkheads on my 3V system and two jockey boxes with 6 taps and have never had to use silicone. It can be frustrating sometimes to get it just right. I sometimes break my 3 vessels down completely and a couple may need tweaking another time or two to get just right since the hole sizes aren't perfectly small.

One time I did screw up hole placement on a fusti lid and ended up try silicone but it didn't work out. It'll make a mess.

The teflon tape can sometimes plug a leak but the real purpose of the tape is to lubricate the threads so that you can better torque the fitting. NPT threads are tapered and as they enter the fitting the threads tighten together to provide the seal.

 

[Broken Crow]

As has been thoroughly stated above, the purpose of teflon tape is not to seal, but these ad-hoc coupler/o-ring/nut combos many of us cobble together are not genuine bulkheads and we need to carefully practice the 'off-label' use of it to fill the threads where they would come in to contact with the inside of the o-ring to avoid seepage along the threads... Just like trying to orient the parts in the correct position when tightened, there's a bit of trial and error and we need to use a bit more than the typical few turns. Also: Looking closely at the pic, While I see that your ball valve is nicely positioned with the handle right at the top, I'm suspecting that you got it that way by tightening the nut on the inside: This is a no-no (but if you absolutely must, then at least use a bit of keg lube on the o-ring and don't turn it too far). Ideally: You'll put a wrench on that nut and hold it on position without turning it and possibly deforming the o-ring; Tighten the valve on the outside so that the o-ring is simply pulled without rotation against the inside.

 

[Brew_Dude41]

I was about to point out that it looks like the body of the vavle is resting on the nut of the bulkhead. That could be preventing the thread from sealing on the valve. If so, it might be seeping back through the threads to that joint.

2 options in my opinion: add an additional gasket between the valve and bulkhead, or back the nut off on the inside of the tun so you get a few more threads available on the outside to get a good seal on the valve.

Personally, if I can, I am trying to get to one or 2 threads clear of the nut on the inside of the tun and using as much of the rest of the bulkhead to get a solid seal outside of the the cooler.

 

[IslandLizard]

it looks like the body of the vavle is resting on the nut of the bulkhead.

To me it looks that there is no nut on the outside of the bulkhead. The threads in the valve body tighten the bulkhead on the outside of the tun. With short bulkheads like this that's the only way, as there's no extra space for a nut plus the valve.

In this case, I would put a large diameter washer between the tun wall and the valve to distribute the force. That way the tun wall (which only has foam inside) won't be compressed/deformed as much when tightened sufficiently to create a positive seal.

In this case a few extra windings of teflon tape will likely help making the seal without overtightening, as the bulkhead threads aren't tapered. Some silicone may still be needed, as it does on my rectangular cooler. He doesn't want wort seeping into the foam-filled wall.

 

[Broken Crow]

It can be done and without sealant...Here's own similar non-leaking, single inner o-ring Igloo:

I think I've identified the kit as this: https://www.ontariobeerkegs.com/weldless-mash-king-bazooka-kit.html which is the current version with o-rings that replaced the eternally headachey flat washer version. Here it is:

Assembled thusly (as the OP has done):

It does not use a coupler, but a short 1-1/2" nipple...the central ring is small enough, that between the cooler walls and outer washer, it allows the o-ring to be tightened over it making excess teflon tape unnecessary; the inner o-ring will have smooth contact.
The First Rule of building your own gear is: Always Buy Extra Parts! Particularly; nuts, washers, o-rings, various sizes of couplers. Without resorting to a pipe wrench, if you have 2 spare locknuts here's how you begin:

Wrap your few turns of tape on the inside, then turn the o-ring and grooved locknut(1) all the way to the middle so the o-ring is wrapped over the smooth ring. Turn nut 2 most but not all the way on. Turn and tighten nut 3 against nut 2..very tight and then with a wrench on nut 3; tighten nut 1 till it won't go any further, then with a pipe-wrench, tighten the coupler against it while still holding with a wrench on nut 3. Now that the inside bits are as far on as they go and the coupler is tightened against it; put your wrench on nut 2 and turn nut 3 off and then you can remove nut 2 by hand, wrap the outer part with tape, insert into the cooler, put your big washer on and then get your ball-valve as far on by hand as you can and then tighten it by holding the coupler on the inside with a pipe wrench and turning the whole ball-valve and not the inner coupler.
You're not likely to get the ball-valve in the proper upright position on the first try, so don't torque it all the way until you've rotated it enough by trial and error..You can back it off a bit to rotate, and I should have mentioned above: Put a bit of keg lube on the o-ring anyway. Getting threaded fittings such as a valve oriented in the correct position is one of those things you 'get a feel for' with practice and with the plastic cooler walls, the final position can be a bit tricky to hit...If I remember mine correctly; I hand tightened the ball valve as much as I could and when I finally got the right position, it required about 180° turn with a wrench to get the handle at the top and be fully torqued.
Hope this is helpful.

EDIT: I forgot to mention: I didn't have a 1-1/2" nipple on hand, (But that is what is inside my own Igloo MT) I used a 2" coupler just for the pictures, yours will be shorter than seen here.
Also: If you don't have a couple spare nuts, you can use a pipe-wrench..but be very careful as that can damage the threads, hence the preferance for 'nut-on-nut'.

 

[Beer Viking]

Thanks for all the help guys. It honestly does not leak that much. It might leak out half a can on beer or a can over an hour so I'm not too worries about it. I know that there would be left over liquid in my mashtun anyways. I might just try it again from scratch with a washer.

Thanks again everyone!

 

[Broken Crow]

Thanks for all the help guys. It honestly does not leak that much. It might leak out half a can on beer or a can over an hour so I'm not too worries about it. I know that there would be left over liquid in my mashtun anyways. I might just try it again from scratch with a washer.

Thanks again everyone!

That actually is a cause for concern: The cooler has an inner and an outer wall. If the seepage is coming from the inside, you'll likely begin collecting wort with the insulation in between the 2 layers. I got my own Igloo second hand..It came with the old flat-washer/massive torque but still leaky combo... The guy I bought it from had only used it twice but there was a trail on the fittings when I finally pried them apart and cleaning up the sticky inside was a nasty job! What I outlined above is the procedure I did myself once I cleaned it and discarded most of the former assembly.
Just on a side note; As has been mentioned are Bobby's True Bulkheads. If you're fed up with this ad-hoc thing, then you'll see why those of us who use Bobby's True Bulkheads are so in love with them. They have a large hex nut center with a groove for the o-ring and no threads under the o-ring. They provide true isolation of the inside and out. Here's the inside and outside views of one; (Yes, I bought spares):

Do you have more gear yet to build? Have you considered trying BIAB? ...Just sayin: It might be well worth your time and money in the long run, to look over what's on offer at brewhardware.com As I said above; Bobby's designed and made a number of unique products specifically for homebrew gear and you can't get it anywhere else in the world.
Just some food for thought.

 

[Bobby_M]

The liquid is sneaking between the nipple and the locknut. Applying teflon tape there should stop it. Of course, you also need it between the valve and nipple if it's not already there.

 

[MograhmDeadbraid]

I'm going to take another crack and assembling my mash tun. Do you know if regular plumbers tape is safe or do you use food grade plumber's tape?

Working at an Ace Hardware and helping a number of commercial brewers in the area, I have sold plenty of the standard white teflon to the brewery's. I have not heard of any issues personally. Now, that being the case, i have heard plenty of leaks from not wrapping the tape on right. That is another story for another day.