Reverse bulkheads?

malx · 03/20/2018, 01:39 PM

Hi, Everyone.

So I'm working on a DIY Sump Build. When doing bulkheads, the general consensus is that the flange side goes on the inside of the tank (since that's the nicer looking side) and the washer needs to go inside the tank as well this way the water does not creep through the little screw pathways and leak out. For my sump build, I need to actually have the flange reversed and have that outside the container with the screw side in. I'd put the washer on the outside so that the water does not sneak under the screw again and out through the flange. Anyone ever do this? Anyone have issues?

Let me know,
Joey

nereefpat · 03/20/2018, 01:53 PM

Gaskets always go on the wet side.

homer1475 · 03/20/2018, 01:56 PM

I did this same thing with my ATS. Just totally reverse the bulkhead(flange and gasket on the dry side), working fine for me, but of course it's not under very much pressure either.

mcgyvr · 03/20/2018, 03:37 PM

Quote:

Originally Posted by nereefpat

Gaskets always go on the wet side.

No.. Gasket always goes under the flange.

Water can/will travel up the threads and the gasket will not stop it..

nereefpat · 03/20/2018, 03:52 PM

That makes sense.

It just goes against my nature to put a gasket on the outside of a container. Before I knew better, I poorly setup a sump once with the flange on the outside and the gasket and threads on the inside. I dealt with the thread leaking issue with lots of Teflon tape (like I said...poor design).

mcgyvr · 03/20/2018, 03:53 PM

And teflon tape is for metallic(metal) threaded connections only and should never be used on PVC or any other plastic threaded fitting

Instead you use a non-hardening thread sealant specifically intended for PVC or whatever plastic it is.. nylon/abs,etc....

nereefpat · 03/20/2018, 04:00 PM

Quote:

Originally Posted by mcgyvr

And teflon tape is for metallic(metal) threaded connections only and should never be used on PVC or any other plastic threaded fitting

Instead you use a non-hardening thread sealant specifically intended for PVC or whatever plastic it is.. nylon/abs,etc....

Agreed. Like I said, before I knew better.

I don't know if the paste would have stayed put underwater in that case. The tape stopped the leaking through the threads...But again, it was a poor design.

malx · 03/20/2018, 04:14 PM

Quote:

Originally Posted by mcgyvr

And teflon tape is for metallic(metal) threaded connections only and should never be used on PVC or any other plastic threaded fitting

Instead you use a non-hardening thread sealant specifically intended for PVC or whatever plastic it is.. nylon/abs,etc....

What happens if you use Teflon tape? I have a few connections with it on my main display. It's been 2 years don't know of any issues yet.

malx · 03/20/2018, 04:15 PM

Quote:

Originally Posted by homer1475

I did this same thing with my ATS. Just totally reverse the bulkhead(flange and gasket on the dry side), working fine for me, but of course it's not under very much pressure either.

Thanks! This won't be under pressure either. I'm using two garbage cans as a sump and need the water to travel from one to the other, it will just trickle over through the 2" PVC hole/pipe.

malx · 03/20/2018, 04:17 PM

Quote:

Originally Posted by mcgyvr

And teflon tape is for metallic(metal) threaded connections only and should never be used on PVC or any other plastic threaded fitting

Instead you use a non-hardening thread sealant specifically intended for PVC or whatever plastic it is.. nylon/abs,etc....

This is what I use on my threaded connections. https://www.amazon.com/Mill-Rose-708..._&dpSrc=detail

It's not Teflon, it's PTFE tape.

windlasher · 03/20/2018, 04:53 PM

Quote:

Originally Posted by mcgyvr

No.. Gasket always goes under the flange.

Water can/will travel up the threads and the gasket will not stop it..

THIS - Under the flange no matter which way you put it.

windlasher · 03/20/2018, 05:02 PM

Quote:

Originally Posted by malx

What happens if you use Teflon tape? I have a few connections with it on my main display. It's been 2 years don't know of any issues yet.

NOTHING: We just went through this.

In short, the reason you don't use Teflon tape on PVC is that it doesn't need it. It's essentially a filler and a lubricant, and most people tend to over tighten it and THAT'S what causes leaks. That and people wrapping the hell out of it and then forcing the screw fitting down which is why it may leak. A few turns will do, i.e, just enough to cover the threads. All it needs is the "filler" part to stop leaks so as long as you don't over tighten it, you will be fine and it will stop leaks.

There are more reefers out there using Teflon tape than not. Yes the non-hardening filler works well, but so does Teflon tape when used correctly

nereefpat · 03/20/2018, 05:04 PM

PTFE and Teflon are the same thing.

PVC fitting threads are tapered, so they don't need it. And the tape can actually cause you to over tighten, cracking the fitting.

mcgyvr · 03/20/2018, 05:06 PM

Quote:

Originally Posted by malx

It's not Teflon, it's PTFE tape.

Teflon is just one of the brand names of Polytetrafluoroethylene (PTFE)..
PTFE = Teflon

Teflon decreases friction can can lead to overtightening of the joint thus causing failure..
Its been used by many people incorrectly for years and many times it doesn't cause any problems and many..many times it does..

Here is an article written by one of the largest manufacturers of PVC fittings..
http://www.lascofittings.com/threads

malx · 03/20/2018, 05:14 PM

Quote:

Originally Posted by mcgyvr

Teflon is just one of the brand names of Polytetrafluoroethylene (PTFE)..
PTFE = Teflon

Teflon decreases friction can can lead to overtightening of the joint thus causing failure..
Its been used by many people incorrectly for years and many times it doesn't cause any problems and many..many times it does..

Here is an article written by one of the largest manufacturers of PVC fittings..
http://www.lascofittings.com/threads

Thanks. I most certainly don't overtighten my joints, I know that could be bad. I am going to use a very small amount of tape with this new build just because that's what I've always done and I don't want to run any risk of leaking. I did just use one layer on my fittings for my main display and no leaks after two years.

windlasher · 03/20/2018, 10:37 PM

Quote:

Originally Posted by nereefpat

PTFE and Teflon are the same thing.

PVC fitting threads are tapered, so they don't need it. And the tape can actually cause you to over tighten, cracking the fitting.

I thought that's what I said but ok. Use it. Don't use too much and don't over tighten. You will be fine.

mcgyvr · 03/21/2018, 04:36 AM

Quote:

Originally Posted by windlasher

I thought that's what I said but ok. Use it. Don't use too much and don't over tighten. You will be fine.

There was only 2 minutes between your post and theirs so I'm quite positive they didn't even see your response.. and nothing wrong with having multiple matching responses..
To me thats the only way I accept any data from the internet.. Never trust a single source..

homer1475 · 03/21/2018, 04:47 AM

All this bickering back and forth about teflon or PTFE tape(FYI they are the same thing), you think someone could actually answer the ops question?

Not a single post in this thread answers the OP's question. He didn't ask where the gasket went or whether to use tape or paste, or what the difference between the 2 is. His specific question was whether he could flip a bulkhead so the flange was on the dry side.

One would think that somewhere in 18 posts someone could have answered the original question.Yes I understand this is a DISCUSSION board, but one would think the original question would get answered.

mcgyvr · 03/21/2018, 06:04 AM

You already addressed his question in your post #3..
So the question was answered by at least one person.. And as you said.. This is a discussion board so discussions occurred...

Obviously you can mount it whichever way you want..
Its just 2 pieces of plastic..
As long as you put the gasket on the correct side all will be just fine..

windlasher · 03/21/2018, 06:12 AM

Quote:

Originally Posted by homer1475

All this bickering back and forth about teflon or PTFE tape(FYI they are the same thing), you think someone could actually answer the ops question?

Not a single post in this thread answers the OP's question. He didn't ask where the gasket went or whether to use tape or paste, or what the difference between the 2 is. His specific question was whether he could flip a bulkhead so the flange was on the dry side.

One would think that somewhere in 18 posts someone could have answered the original question.Yes I understand this is a DISCUSSION board, but one would think the original question would get answered.

By my read... several people answered his first question and then several people answered his second question followed by his third which was about Tape. Who's bickering?

We are discussing various takes on plumbing.

nereefpat · 03/21/2018, 07:26 AM

Quote:

Originally Posted by windlasher

I thought that's what I said but ok. Use it. Don't use too much and don't over tighten. You will be fine.

Quote:

Originally Posted by mcgyvr

There was only 2 minutes between your post and theirs so I'm quite positive they didn't even see your response.. and nothing wrong with having multiple matching responses..
To me thats the only way I accept any data from the internet.. Never trust a single source..

Yep. Windlasher is a faster typer than I.

malx · 03/29/2018, 12:11 PM

Wow lots of debate here. I think I found a non hardening thread sealent. Will this work? How do I know if it’s reef safe?

Sent from my iPhone using Tapatalk

mcgyvr · 03/29/2018, 12:15 PM

yep.. Thats fine to use..

malx · 03/29/2018, 01:05 PM

Quote:

Originally Posted by mcgyvr

yep.. Thats fine to use..

Sweet! I didn't think I would have time to find some but I ended up finding it at this hardware store near me called McFadden-Dale. Weird name, but they have lots of cool stuff!

mcgyvr · 03/29/2018, 05:07 PM

Just wanted to post this here..
Perfect example what happens when you use teflon tape/overtighten a joint..
http://www.reefcentral.com/forums/sh....php?t=2672229

03/20/2018, 01:39 PM	#1
malx Registered Member Join Date: Aug 2003 Location: Las Vegas Posts: 1,324	Reverse bulkheads? Hi, Everyone. So I'm working on a DIY Sump Build. When doing bulkheads, the general consensus is that the flange side goes on the inside of the tank (since that's the nicer looking side) and the washer needs to go inside the tank as well this way the water does not creep through the little screw pathways and leak out. For my sump build, I need to actually have the flange reversed and have that outside the container with the screw side in. I'd put the washer on the outside so that the water does not sneak under the screw again and out through the flange. Anyone ever do this? Anyone have issues? Let me know, Joey

03/20/2018, 01:53 PM	#2
nereefpat Registered Member Join Date: Apr 2016 Location: Central Nebraska Posts: 3,190	Gaskets always go on the wet side. __________________ Pat Current Tank Info: 125 in-wall , 40b sump. 6 bulb T5. ASM G2 skimmer. LPS and leathers

03/20/2018, 03:52 PM	#5
nereefpat Registered Member Join Date: Apr 2016 Location: Central Nebraska Posts: 3,190	That makes sense. It just goes against my nature to put a gasket on the outside of a container. Before I knew better, I poorly setup a sump once with the flange on the outside and the gasket and threads on the inside. I dealt with the thread leaking issue with lots of Teflon tape (like I said...poor design). __________________ Pat Current Tank Info: 125 in-wall , 40b sump. 6 bulb T5. ASM G2 skimmer. LPS and leathers

03/20/2018, 03:53 PM	#6
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	And teflon tape is for metallic(metal) threaded connections only and should never be used on PVC or any other plastic threaded fitting Instead you use a non-hardening thread sealant specifically intended for PVC or whatever plastic it is.. nylon/abs,etc.... __________________ Who me?

03/20/2018, 05:04 PM	#13
nereefpat Registered Member Join Date: Apr 2016 Location: Central Nebraska Posts: 3,190	PTFE and Teflon are the same thing. PVC fitting threads are tapered, so they don't need it. And the tape can actually cause you to over tighten, cracking the fitting. __________________ Pat Current Tank Info: 125 in-wall , 40b sump. 6 bulb T5. ASM G2 skimmer. LPS and leathers

03/20/2018, 01:56 PM	#3
homer1475 Registered Member Join Date: Mar 2015 Location: Upstate NY Posts: 5,313	I did this same thing with my ATS. Just totally reverse the bulkhead(flange and gasket on the dry side), working fine for me, but of course it's not under very much pressure either. __________________ 80G SCA Build: http://reefcentral.com/forums/showthread.php?t=2560256 Originally posted by der_wille_zur_macht: "He's just taking his lunch to work"

03/21/2018, 04:47 AM	#18
homer1475 Registered Member Join Date: Mar 2015 Location: Upstate NY Posts: 5,313	All this bickering back and forth about teflon or PTFE tape(FYI they are the same thing), you think someone could actually answer the ops question? Not a single post in this thread answers the OP's question. He didn't ask where the gasket went or whether to use tape or paste, or what the difference between the 2 is. His specific question was whether he could flip a bulkhead so the flange was on the dry side. One would think that somewhere in 18 posts someone could have answered the original question.Yes I understand this is a DISCUSSION board, but one would think the original question would get answered. __________________ 80G SCA Build: http://reefcentral.com/forums/showthread.php?t=2560256 Originally posted by der_wille_zur_macht: "He's just taking his lunch to work"

03/21/2018, 06:04 AM	#19
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	You already addressed his question in your post #3.. So the question was answered by at least one person.. And as you said.. This is a discussion board so discussions occurred... Obviously you can mount it whichever way you want.. Its just 2 pieces of plastic.. As long as you put the gasket on the correct side all will be just fine.. __________________ Who me?

03/29/2018, 12:11 PM	#22
malx Registered Member Join Date: Aug 2003 Location: Las Vegas Posts: 1,324	Wow lots of debate here. I think I found a non hardening thread sealent. Will this work? How do I know if it’s reef safe? Sent from my iPhone using Tapatalk

03/29/2018, 12:15 PM	#23
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	yep.. Thats fine to use.. __________________ Who me?

03/29/2018, 05:07 PM	#25
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	Just wanted to post this here.. Perfect example what happens when you use teflon tape/overtighten a joint.. http://www.reefcentral.com/forums/sh....php?t=2672229 __________________ Who me?