Need help with GFPP bulkhead question:

[WhatCouldGoWrong71]

Thoughts on below?

“Supply House” shipped one of my bulkheads incorrectly. I ordered Hayward BFAS PVC with EPDM thread/thread. The one in question is GFPP/EPDM.

I’m not gluing. But I now will need to figure out what thread sealant to use. The model number to the Hayward bulkhead I received is BFAS4030TES. Before you ask, lol, I’m going 3” to fix a freak accident with. 1.5” hole I drilled. If woody had just not switched bits halfway through this hole I would be pester you right now, sigh… lol
The only thing I found on R2R is:
https://www.reef2reef.com/threads/gfpp-bulkheads-and-pvc.854438/
I will have about 1k watts of halides over a 48”x48” area, plus LED and T5.

Below is what I found on the internet on GFPP
GFPP stands for
Glass Fiber Reinforced Polypropylene.
It is a composite material created by combining homopolymer polypropylene resins with glass fibers.
This reinforcement with glass fibers significantly enhances the material's properties, including:

• Increased strength and stiffness
• Higher impact resistance
• Improved surface hardness
• Higher continuous temperature tolerance
• Reduced distortion under long-term stress

GFPP is used in various applications such as:

• Appliances
• Electrical components
• Automotive parts
• Utility products

 

[UncommonSense]

Thoughts on below?

“Supply House” shipped one of my bulkheads incorrectly. I ordered Hayward BFAS PVC with EPDM thread/thread. The one in question is GFPP/EPDM.

I’m not gluing. But I now will need to figure out what thread sealant to use. The model number to the Hayward bulkhead I received is BFAS4030TES. Before you ask, lol, I’m going 3” to fix a freak accident with. 1.5” hole I drilled. If woody had just not switched bits halfway through this hole I would be pester you right now, sigh… lol
The only thing I found on R2R is:
https://www.reef2reef.com/threads/gfpp-bulkheads-and-pvc.854438/
I will have about 1k watts of halides over a 48”x48” area, plus LED and T5.

Below is what I found on the internet on GFPP
GFPP stands for
Glass Fiber Reinforced Polypropylene.
It is a composite material created by combining homopolymer polypropylene resins with glass fibers.
This reinforcement with glass fibers significantly enhances the material's properties, including:

• Increased strength and stiffness
• Higher impact resistance
• Improved surface hardness
• Higher continuous temperature tolerance
• Reduced distortion under long-term stress

GFPP is used in various applications such as:

• Appliances
• Electrical components
• Automotive parts
• Utility products

The 3/4” NPT GFPP Banjo ball unions on my fertilizer injection system seem happy to just be Teflon taped; even with stainless steel threads on one side and PA6GF-30 threads on the other side, at city water pressure!

However, at 3”; significantly more care needs to be taken to seal the threads correctly, and standard Teflon tape is far too narrow to effectively seal the threads…

I haven’t done anything that big in a while, and it seems that PTFE tape has been phased out for any plastic fittings over 2”… but, this extra wide PTFE tape is what used to be used for these larger plastic threads; despite McMaster-Carr not listing it for plastic application at 3” anymore…

Alternatively, this product is specifically for potable water, and is specifically listed as PP compatible! (Still max plumbing size of 2” though…)

 

[WhatCouldGoWrong71]

@UncommonSense you have that outside? So then that answers the UV question. I’ll have to call this plumbing house in town and see what they say about what to use, but, I have this and I would think it would work, it’s the same as your second option:

Dumba$$ me put a brand need diamond hole saw on my drill when I was already halfway through. I wasn’t thinking, it was late and I’m an idiot. These are 1.5”, the 2” doesn’t even make a dent. The 3” takes care of it. I’ll have to get creative if I don’t pull this off…

 

[UncommonSense]

@UncommonSense you have that outside? So then that answers the UV question. I’ll have to call this plumbing house in town and see what they say about what to use, but, I have this and I would think it would work, it’s the same as your second option:

Dumba$$ me put a brand need diamond hole saw on my drill when I was already halfway through. I wasn’t thinking, it was late and I’m an idiot. These are 1.5”, the 2” doesn’t even make a dent. The 3” takes care of it. I’ll have to get creative if I don’t pull this off…

Yup! outside, direct sunlight a few hrs a day, under city pressure, with fertilizer in it for well over a decade straight! UV is definitely a non-issue!

The sealant you have will honestly probably work fantastic! — if you are skeptical, you can always find a few sacrificial smaller NPT PVC fittings to seal with it? let it fully cure per-instructions, then, try pressurizing it to city water pressure to see if you get any leaks?

Ouch! Those are some sizable spall chips!! Would you like a recommendation to properly fix that once and for all?

 

[WhatCouldGoWrong71]

Yup! outside, direct sunlight a few hrs a day, under city pressure, with fertilizer in it for well over a decade straight! UV is definitely a non-issue!

The sealant you have will honestly probably work fantastic! — if you are skeptical, you can always find a few sacrificial smaller NPT PVC fittings to seal with it? let it fully cure per-instructions, then, try pressurizing it to city water pressure to see if you get any leaks?

Ouch! Those are some sizable spall chips!! Would you like a recommendation to properly fix that once and for all?

Yes please. I assume the only current fix is to drill a new larger hole? I’m way out in front of my skis on this one. This will be for. Closed loop application, FYI.

 

[UncommonSense]

Yes please. I assume the only current fix is to drill a new larger hole? I’m way out in front of my skis on this one. This will be for. Closed loop application, FYI.

Well, what I would do in your situation is go to my local glasscutter, or call a glass manufacturer in the nearest larger city where one exists; and order yourself a small square plate of thicker float glass!

This glass plate can be drilled to your current hole size, then siliconed on the inside of the tank, over the existing hole, aligning your two drilled glass holes so the bulkhead is just going through a thicker glass hole!

Edit: You can also request this plate of glass (could be as thin as 1/4”, but thicker is always better) has beveled, or at least clean cut and smoothed edges too, for a nominal additional fee! (And don’t order tempered!!)

 

[WhatCouldGoWrong71]

So the plate would have to be thicker? This is 1”. And, how much larger then the hole would the glass need to be? One more, would you use the bulkhead to squeeze the silcon? Or use something heavy, let it cure, then apply bulkhead?

 

[UncommonSense]

For context; Here’s how I did four bulkheads in danger-close proximity (5.75” ID) for my hexagon!

The bottom of the tank was only 1/4” acrylic (technically 6mm), so I used a piece of 1/2” cell cast acrylic from a scrapped tank to “double up” the bottom of the tank!

The bulkheads seal on the inside of the tank, but clamps the tank bottom, and 1/2” acrylic with the nuts!

 

[UncommonSense]

So the plate would have to be thicker? This is 1”. And, how much larger then the hole would the glass need to be? One more, would you use the bulkhead to squeeze the silcon? Or use something heavy, let it cure, then apply bulkhead?

The plate you add would not need to be thicker; 3/8” (sold in metric, so 10mm) would likely be fine to overkill; but 12mm (1/2”) is also available without too much fuss!

19mm (3/4”)-25mm (1”) thick is also a possibility, but expect a jump in price, and a longer lead time if they need to literally cast the silica to glass for the order!

The factory tank bottom glass is doing the majority of the heavy lifting in this application, your added plate is only stressed where it bridges the chips, and is being squeezed by the bulkhead gasket! — the chips will be full of silicone though, helping to relieve that stress!

I would ideally go for 100% larger than the hole diameter on all edges of the hole; so a 2” diameter hole would receive a 6”x6” plate! — though technically it only NEEDS to be as wide as the bulkhead flange’s OD!

Hmm… I think you could just install the bulkhead to squish this down; though you may get more precise results if you just push it down by hand until all bubbles are out, then let it cure…

Consider masking around where you’ll wipe the squished out silicone so you can pull it before the silicone tacks to get clean lines!

 

[WhatCouldGoWrong71]

That is danger closer. A 3” bulk is huge, lol.


I think if I were to go this route, I would have to order the “long” version of this bulkhead. I always use “short”. I inverted the bulkhead for example:

 

[UncommonSense]

That is danger closer. A 3” bulk is huge, lol.


I think if I were to go this route, I would have to order the “long” version of this bulkhead. I always use “short”. I inverted the bulkhead for example:

Yes, you would likely need a “long” version if you used any glass over 1/4” thick; but that’s okay!

— The silicone takes 7 days to fully cure to maximum strength, and the glass still needs to be ordered, cut, edge finished, then drilled by you!

 

[WhatCouldGoWrong71]

This actually feels like a better fix. 3/8th over time you won’t even notice with all the coralline. Hmmm

 

[WhatCouldGoWrong71]

Yes, you would likely need a “long” version if you used any glass over 1/4” thick; but that’s okay!

— The silicone takes 7 days to fully cure to maximum strength, and the glass still needs to be ordered, cut, edge finished, then drilled by you!

Actually, I think I can get the hole punched through it also. This is great, I can now plumb the entire closed loop and just wait on the last little connection. I think you sold me.

 

[WhatCouldGoWrong71]

Can’t thank you enough. This has put me more at ease. I’m still an idiot though.

 

[UncommonSense]

Can’t thank you enough. This has put me more at ease. I’m still an idiot though.

Consider it a learning lesson! I would have likely made the same mistake as I overthought wearing out a bit cutting through a full inch of glass…. Now we both know!!

 

[UncommonSense]

Actually, I think I can get the hole punched through it also. This is great, I can now plumb the entire closed loop and just wait on the last little connection. I think you sold me.

Remember, float glass (aka: “annealed”)!

See if they can bevel the edges of one face only without charging a small fortune! — failing that, request smooth edges on one face of the plate!

You can also request it in frosted finish (acid etched, or media blasted) if you want to backlight it and make it look le’fancy!

They can also cut the hole for you, and even temper it after cutting the hole; if you want to really throw money at the problem!

Good luck! I’m glad we found a tidier fix!

 

[WhatCouldGoWrong71]

I’ll ping you here, lol, when I go to start the operation. I may should stream it as people can lay odds if I’m going to muck it up again. I’m just ordered black ASI. It should help it blend right in until the coralline shows up. This was an unexpected set back. I have a remote sand bed with TBS sand and my freshly harvested TBS rock in the sink. I’m just running salt water between the two sumps and letting lots of ambient light hit them. Tank is going to be a look down tank. 48x48x18. Bare bottom and mostly everything on tiles or some rock.

 

[UncommonSense]

I’ll ping you here, lol, when I go to start the operation

Sounds good!

may should stream it as people can lay odds if I’m going to muck it up again.

haha you’ll be fine!

Just using masking tape around 3/8”-1/2” away from the perimeter of the glass plate you’re adding (test fit plate to make sure it all lines up first too!)

You’ve got ten minutes of work time; slow is fast here…

Glass prep is key; do NOT use acetone!! — It leaves a film; here’s an excerpt from an article on lab glassware cleaning that explained that one to me, after I learned about acetone, the hard way…

You’ll want to lay a very large bead around the radius of the hole on the tank, maybe 1/2” + thick, around 1” away… once the new glass plate is pressed or clamped down; this will cause the silicone bead to “spread out” between the glass panes, pushing out air without trapping any as bubbles!

Wipe the excess silicone with one finger to make a nice fillet like you see in our tanks! — wipe that finger on an alcohol soaked rag to clean it quick!

Pull your masking tape before the 10 minute tooling time is up, and it’ll look like a pro did it!

Tank is going to be a look down tank. 48x48x18. Bare bottom and mostly everything on tiles or some rock.

This tank is going to be absolutely stunning when it’s up and running!! I look forward to it!!

Just out of curiosity… Have you considered some sort of floating magnifying glass or glass pane to get a clear view down into select areas from the top, despite surface agitation?

 

[WhatCouldGoWrong71]

dang, thank you again. I was wondering about how to apply the silicone. I was worried about air pockets. Yeah, this is what I am going to do.

Yes!!! So, on my big display, I rigged the lighting rack so that it runs on rails and I can move it 6 feet out of the way very easily. It even has a trolley for the electrics. I did this so I can stand on a step stool and look down at it. My only regret was not going 48” wide. I rigged several Kessils to the ceiling so I can see the colors!

So, the tray I wish it would be worth it in my other. But for this one, I’m going to see what the lights produce at 24” instead of 14”, but I’m not wishful. Either way, I’m going to make it so the lights retract to the ceiling. I’d like to get a floating tray 24x24.

 

[UncommonSense]

Wow! That array is SERIOUS! I’m guessing you won’t have many issues at 24”; particularly with halides!

For the sliding light fixture; Have you ever heard of horticultural “light movers”?

It’s essentially a rail of a set length with a motor to slide the attached lighting from one end to the other over the course of the day!

I could see repurposing one or two of those to not only help with a realistic sun movement over the tank (possibly helping with any shading that may exist!), but also to just pressing a button and have the entire array slide to the side!