Wooden External Overflow Box?

ah ok, i understand now. how many inches in depth is your weir. and how far down is it. your tank looks great by the way and glad your posting pictures of it for others to see.

Thanks, Dryworm.

If I understand you correctly, you are asking how deep the internal overflow-box is, as measured from the front of the weir panel to the back wall of the aquarium. If that is your question, the answer is: 2.5".

If I understand you correctly, you are also asking how tall the internal overflow-box is, as measured from the floor of the internal box, to the top of its weir panel. If that is your question, the answer is: 4.75"

I will keep posting pictures of progress here. This water-proof box has to stand the test of water, by not leaking. I will photograph the final assembly and it's leaking or leak-proof status over time.

Thanks.
 
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i would make sure you have as much epoxy as you can inside the holes of the box to tank side...those holes will always have water standing in them...as username said, the water will seep past the threads and be standing in the glass holes and wooden holes of the junction between tank and box...any pin holes in the epoxy will allow water to get in the wooden box, and then you get swelling and possibly serious issues...

In general, this is great advice. However, as applied here in the horizontal-bulkhead setup, a slight correction needs to be made. The prediction that the standing water that propagates along the threads of the bulkhead from the internal overflow box will permeate the cylindrical walls of the bulkhead holes in the wooden, overflow box will not actually happen here. Things get so turned around in discussion that a plain view of the actual construction reveals this to be true. The side of the setup that will have the threads submerged in water is the glass, internal overflow-box, not the wooden, external overflow-box. To be sure, there are no bulkhead threads exposed to water in the external, wooden overflow-box, just a snugly fit flange and gasket.

Thus, when the water from the internal overflow box migrates along the threads of the bulkhead positioned there, the water becomes stopped by the gasket seal positioned between the tank and the wooden box outside the tank, just as UserNameInUse has indicated. That trapped water will not soak the cylindrical walls of the wooden, external overflow-box . Again, this standing water is not in the wooden box; it is in the glass box. There are no seeping/soaking concerns for the glass panels because glass is waterproof.

Thanks.
 
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Is the flange side of the bulkhead on the inside of the aquarium or on the inside of the wood box?

If it the flange is on the inside of the wood box, then water can travel through the threads from the aquarium to the wood box holes, and he is right that in that set up, any pinholes will allow water to seep into the wood over time.
 
Is the flange side of the bulkhead on the inside of the aquarium or on the inside of the wood box?

If it the flange is on the inside of the wood box, then water can travel through the threads from the aquarium to the wood box holes, and he is right that in that set up, any pinholes will allow water to seep into the wood over time.

Hi, UserNameInUse. The flange side of the bulkhead is on the inside of the wood box. Two gasket/seals are placed: (1) beneath the flange head, in the wood box; and (2) between the wood box and the aquarium's back wall.

I was given to understand in previous posts of this thread that the gasket/seal placed between the wood box and the aquarium wall would stop the water migration from the tank and hold it back in the hole from where it came. But perhaps that is not so. On second thought, I guess that could not be so because, once the water is in the thread of the bulkhead, it would not be stopped by the gasket outside the aquarium for the same reason it would not be stopped by a gasket placed inside the aquarium: the gasket's inner circumference lies outside the ring of threads and has no ability to stop water channeling in the groove of the threads. Wow. What is to stop leaking then?

Given what you are saying here, if the water is going to travel along the threads past the seal between the wood box and the glass tank, then what function is served at by the gasket/seal there? Also, couldn't such migrating water simply drip to the floor before it gets to the hole at the wood box, if the stem-hole junction is tight? NanoReefWannabe spoke of "standing water." Are you saying that the water in the groove would be standing water? Hopefully, the gasket serves some useful function, aside from absorbing friction with the tank, when the wood expands and contracts. What specifically prevents leakage in this setup, besides assuring that the paint in the hole is sealed from any pinhole leaks? I don't think I am getting a clear understanding here.

Thanks for your advice and comments.
 
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Can't Plumber's Grease Stop Water Migration on Bulkhead Thread?

Can't Plumber's Grease Stop Water Migration on Bulkhead Thread?

It has been recommended that one ensure that the epoxy paint applied the cylindrical walls of the holes of the wooden-box have no tiny holes. Recall that the bulkhead flange is secured against the wall of the wooden box, and its threaded, bulkhead stem protrudes through the wooden-box holes "forward," to the glass holes of the tank, where the stem is secured by a bulkhead nut. The concern is that water will migrate from the submerged bulkhead stem in the glass box, along the bulkhead threads, past the gasket/seal secured between the wooden-box and tank, and into the wooden-box-holes, where it will "stand" and potentially seep into the cylinder walls of those wooden-box holes.

But here is my question: doesn't it make sense to apply plumber's grease all along the threaded bulkhead stem, to prevent such water migration along the threads? Wouldn't this be a solution or at least reduce the risk of water migration into the walls of the wooden-box-holes? This seems like it would work, but it would be most helpful to hear from you all on this point.

Thank you.
 
the gasket between the back of the tank and the wood box serves the exact same purpose as the gasket behind the flange...water cannot migrate through the gasket when it is squished between two flat surfaces...

if you setup the bulkhead with no gasket between the tank and the box you would have instant flood of proportions you dont care to see...

the shaft and threaded portion of the bulkhead are obviously smaller then the hole you drilled...typically it is about 1/16" all the way around the bulkhead, water can travel through this 1/16" gap from the nut side all the way down to the flange side, but cannot pass the flange when the gasket is in place...essentially the overflow box serves as a second flange and the gasket against it stops water from pouring out...the gasket doesnt stop water from traveling along the shank of the bulkhead, it only stops it from passing the flange...

so in this case (with water on both sides of the bulkhead) everything that is in the holes will be wet...the thickness of the hole in the glass tank, the thickness of the hole in the wooden box, the thickness of the inner diameter of the gaskets (both of them) and the entire length of the bulkhead shaft(inside obviously, and out)
 
It has been recommended that one ensure that the epoxy paint applied the cylindrical walls of the holes of the wooden-box have no tiny holes. Recall that the bulkhead flange is secured against the wall of the wooden box, and its threaded, bulkhead stem protrudes through the wooden-box holes "forward," to the glass holes of the tank, where the stem is secured by a bulkhead nut. The concern is that water will migrate from the submerged bulkhead stem in the glass box, along the bulkhead threads, past the gasket/seal secured between the wooden-box and tank, and into the wooden-box-holes, where it will "stand" and potentially seep into the cylinder walls of those wooden-box holes.

it is not a concern, it is a fact.
But here is my question: doesn't it make sense to apply plumber's grease all along the threaded bulkhead stem, to prevent such water migration along the threads? Wouldn't this be a solution or at least reduce the risk of water migration into the walls of the wooden-box-holes? This seems like it would work, but it would be most helpful to hear from you all on this point.

Thank you.

only one solution, make sure the inner thickness of the holes is adequately painted/ epoxied...

water will go around and under the nut as well as along the threads, plumbers grease may help to some extent, but then you risk trapping the water in there and having it become stagnant, possibly filled with poop etc as overflow water often is...since the threads are standard straight cut threads (same as a nut and bolt) it is very difficult to make it water tight...

silicone also isnt an option as it wont adhere to plastic well either, and it will not be long before the water can wiggle its way under it...
 
the gasket between the back of the tank and the wood box serves the exact same purpose as the gasket behind the flange...water cannot migrate through the gasket when it is squished between two flat surfaces...if you setup the bulkhead with no gasket between the tank and the box you would have instant flood of proportions you dont care to see...the shaft and threaded portion of the bulkhead are obviously smaller then the hole you drilled...typically it is about 1/16" all the way around the bulkhead, water can travel through this 1/16" gap from the nut side all the way down to the flange side, but cannot pass the flange when the gasket is in place...essentially the overflow box serves as a second flange and the gasket against it stops water from pouring out...the gasket doesnt stop water from traveling along the shank of the bulkhead, it only stops it from passing the flange...so in this case (with water on both sides of the bulkhead) everything that is in the holes will be wet...the thickness of the hole in the glass tank, the thickness of the hole in the wooden box, the thickness of the inner diameter of the gaskets (both of them) and the entire length of the bulkhead shaft(inside obviously, and out)

Thanks, NanoReef. It's a little clearer now. You're saying there are two sources of water seepage. The first occurrence of water seepage happens between the circumferential clearance lying between the exterior wall of the bulkhead shaft and the wall of the hole it protrudes--roughly 1/16". This seepage is quite great, but is stopped by the gasket positioned between the tank and the wood box. The second occurrence of water seepage happens along the threads of the bulkhead shaft, which is much less voluminous, but must be allowed passage because there is no way to prevent it. However, one can control the potential harm it does by not allowing the water to seep through the wood at the end of its path.

it is not a concern, it is a fact. only one solution, make sure the inner thickness of the holes is adequately painted/ epoxied...water will go around and under the nut as well as along the threads, plumbers grease may help to some extent, but then you risk trapping the water in there and having it become stagnant, possibly filled with poop etc as overflow water often is...since the threads are standard straight cut threads (same as a nut and bolt) it is very difficult to make it water tight...silicone also isnt an option as it wont adhere to plastic well either, and it will not be long before the water can wiggle its way under it...

Thanks, Nano. The single solution you propose is what I must go with. My concern here is that in painting the wood-box holes with multiple coats of epoxy already, I have found that the 1/16" circumferential gap has been closed up, such that the bulkheads have to be hand-turned, like a screw, to allow their shafts to obtain passage through the holes. Thus, the paint in the cylindrical holes will be very tight, and I am not sure I can fit more layers of paint in there. My options are to re-bore the holes to a larger size or try one more thin coat of epoxy in hopes it will not close up that gap again.

Your thoughts? Thanks, again.
 
Guys, this whole debate is centered on the possibility of water seeping into the epoxy-coated wood. Given the careful and thorough craftsmanship we can see in SkyReef's photos, I wouldn't really be concerned that this is even a remote possibility. If we're worried about water penetrating the wood along the bore of the hole, why aren't we worried about the entire premise of making a wood overflow box?

Just coat the wood thoroughly, check for pinholes, fill any you find, and be done with it.
 
Almost There...

Almost There...

STATUS UPDATE:

Today, I sanded down the circumferential walls of the horizontal, bulkhead holes, and painted them with one last coat of waterproof epoxy paint. Please recall that there was some debate about such locations being prone to pinholes in the epoxy, leading to water intrusion into the wood. This painting today aimed at eliminating that risk.

I also flipped the box, upside-down to paint/seal the stainless steel, counter-sunk screw heads, with the waterproof epoxy paint.

Next steps:

  • Let everything dry a few days;
  • Assemble all components with wooden-supports below;
  • Water-Test the box for holding-capacity; and
  • Eventually, run an extended water-test of the entire BeanAnimal setup.

I'll continue to post pictures of progress, as it unfolds. As always, comments, suggestions, advice are always welcomed.

Here are some pictures of today's work:

Pictures 1-2: Horizontal, bulkhead holes, sanded down to receive a final coat of paint.

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Pictures 3-7: Painting the circumferential walls of the horizontal, bulkhead holes:

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Pictures 8: Epoxy Paint Drying on the Stainless Steel, Counter-Sunk Screw Head:

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How wavy is the finish? Can you lay a straight edge across it and check the levelness of the surface?

I only ask as from the photos it looks pretty uneven and may pose a problem with getting a good seal on the gasket. It could also be very minor and just the way it photographed.
 
How wavy is the finish? Can you lay a straight edge across it and check the levelness of the surface?

I only ask as from the photos it looks pretty uneven and may pose a problem with getting a good seal on the gasket. It could also be very minor and just the way it photographed.

Hi, Username. Thanks for your question. The orange-peel effect is caused by the nap of the roller brush. It's uneven quality is not extreme. If it should threaten to impair the gasket/seal's ability to seal the hole, I will sand down the footprint of the gasket/seal, to smooth things out. There are many coats of epoxy paint, and a light sanding should not impair the overall waterproof function of the epoxy-paint. I will pay particular attention to the issue, when final assembly is made.

Here are some pictures you asked for: a straight-edge across the holes. Thank you.

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i am thinking that surface is going to make sealing the bulkhead(s) tricky, both gaskets will need to sit perfectly flat to seal properly....another thing too, is that the three horizontal holes will need to be flush with one and other, you will be placing a decent amount of stress on the glass when you tighten the bulkheads, which could potentially torque the glass..
 
i am thinking that surface is going to make sealing the bulkhead(s) tricky, both gaskets will need to sit perfectly flat to seal properly....another thing too, is that the three horizontal holes will need to be flush with one and other, you will be placing a decent amount of stress on the glass when you tighten the bulkheads, which could potentially torque the glass..

Thanks for your observations, NanoReefWanabe. It sounds like you are recommending that I apply a final sanding to the entire panel of wood that interfaces with the tank's glass, to effect a uniform, flush surface, rather than to merely sand the footprint of the seals at the holes. There are actually five holes to contend with here, not just three, and I hear what you are saying. I am hoping to minimize the potential for wracking of the rear glass panel, by having the principal structural support for the external overflow box come from beneath the box, in the form of wooden supports. As well, the internal overflow-box adds stiffness to the back panel of glass, to cut down on the risk of wracking. Thus, hopefully, I won't have to tighten the bulkhead nuts too tightly. We'll check it out next weekend again, after I sand the panel having the five holes down with an electric sander, on both sides of the panel. With a smooth, flat finish, it should be fine.

I'm hopeful that all will work out well. Thanks.
 
Sanded Down Wavy Surface and Gorilla-Patched Divot at Bulkhead Hole

Sanded Down Wavy Surface and Gorilla-Patched Divot at Bulkhead Hole

STATUS UPDATE:

In follow-up to suggestions by UserNameInUse and NanoReefWanabe that I make as smooth as possible the surface of the epoxy-painted, external overflow-box, I sanded down the panel in question. Recall that the concern here is to ensure that the bulkhead seal/gasket will properly seal the junction of the back of the aquarium glass and the outside of the external overflow-box. This requires a smooth contact-surface. UserName and Nano had pointed out that the pictures of the surface of the panel (see previous post above, e.g., Post No. 93) depicted a surface that was too wavy to accommodate the bulkhead seal/gasket in a proper fashion. These were very good observations by UserName and Nano, and the surface now is much smoother, after sanding. The pictures provided below illustrate the current degree of smoothness, after sanding.

On a separate issue, I wanted to patch a small divot or gouge existing at the edge of one of the horizontal, bulkhead holes. In researching the possibilities for patching materials, I discovered that Gorilla Glue mixed directly with water can serve the purpose, as it expands to fill a taped area around the divot. Given its waterproof quality, it should resist corrosion as a filler. Given that it will not be used to bind pieces of wood, but only to serve as a filler, the demands placed on the glue will be significantly less than in typical bonding scenarios. I only need it to serve as a filler, to help the bulkhead gasket/seal have a uniformly flat surface to which to attach, once sanded down.

Here are some pictures. Other pictures will follow, once progress develops. Right now, I am waiting for the Gorilla Glue to dry, after which time, I will sand it down, and the entire footprint of the gasket/seal will have a uniformly flat surface to seal. As always, comments, suggestions, and advice gladly welcomed.

PHOTOS 1-3: Close-up shot of three of the five, horizontal bulkhead holes, after being sanded down.

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PHOTOS 4-5: This bulkhead hole has a divot, requiring a patch. These pictures depict a patch-repair in process: the foam is expanding Gorilla Glue inside a taped area that contains the divot or gouge. Note: the divot or gouge exists beneath the painted surface, so there is no need to waterproof the surface of the divot or gouge:

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PHOTO 6: A wide shot of the box after being sanded down, and during the patch-repair at one hole:

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that looks better, my concern was not with the weight of the box pulling on the glass, as you had already said you were building legs for it...

my concern was more based on the variances in the thickness of the epoxy from hole to hole...ie if one bulkhead were tightened the next would not be the same distance away from the tank, as miniscule as 1mm could put a lot of stress on the back of the glass tank...especially if each bulkhead varied by +/- 1mm...it would be like having a 3mm thick gasket between the box and tank on 3 of the bulkheads and the 2 in between having either 4mm or 2mm thick gaskets, it would essentially put a wave in the back of the glass which is stressful especially with 5 holes in it...meh perhaps my concern is a moot point...hook her up and fill it already, it has been a good month now...
 
Test Run Successful

Test Run Successful

STATUS UPDATE:

I finally completed the PVC plumbing on the entire system today. Doing so enabled me to hook up and test the external overflow-box. The initial test of the entire overflow system was successful:

1. Internal Overflow-Box is Leak-proof?: Check;
2. Junction between Tank and Internal Overflow-Box Is Leak-Proof?: Check;
3. External Overflow-Box is Leak-proof?: Check;
4. BeanAnimal Overflow System Drains Water Safely and Silently and is leak-proof?: Check; and
5. External Pump pumps water back to Display Tank and is leak proof?: Check.

I have posted some pictures below. I will give it a more extended testing and provide an update later.

In the meantime, I have bigger problems: when I was unscrewing the valve assembly on a 1.5" PVC pipe, the union joint was too tightly assembled and would not unscrew. So I used more leverage to unscrew the valve assembly, which caused the entire pipe to torque the rear glass panel, like a 3-foot wrench. This caused the back, glass panel of the aquarium to crack. :(

The good news is that the external overflow-system and its plumbing is completely detachable with union joints and bulkheads. So none of the work on the external overflow-box or plumbing is wasted. All I have to do is buy a new 75-gallon tank ($179.99) and drill the glass holes from the imprint of the old holes, then slide the tank onto the bulkhead assembly of the external overflow-box. It should be very easy to match up the holes to the external box. I also have to tear down the glass, weir assembly of the internal overflow-box in the cracked tank, to re-use it in the new tank. This has set me back about a week. But I am very glad the wooden overflow box has passed the first test and the plumbing system works fine. That tedious work is behind me, and the work of drilling holes and rebuilding the internal overflow-box should not take too much time. Finally, I have to paint the back of the aquarium again, with black, Krylon-Fusion paint. The fun never ends.

PICTURES:

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Looks good, sorry to hear about the tank cracking.

Thanks, NemosWorld.

Hey, everyone. I'm off to Sacramento now to get another tank. A thought occurred to me: when I set up the new tank, why not insert the bulkheads with the flange side positioned in the internal overflow-box, not in the wooden, external overflow-box, as it was in the old tank? Please recall that the design of the build is such that the internal overflow-box is too "skinny," front to back, to accommodate inserting the bulkhead "over the top" of the weir into the "trough" of the internal overflow-box. Such a "skinny" design is aesthetic pleasing, but leaves little room for such maneuvers inside the internal overflow-box. That is why I had the flange side of the bulkhead positioned inside the wooden, external overflow-box, not in the internal overflow-box. As discussed below, when constructing my new tank, I might achieve better protection from water leakage at the bulkheads if I put the flange side of the bulkhead inside the internal overflow-box, not the external overflow-box.

You might ask how can I insert the bulky flange-side of the bulkhead into the skinny, internal overflow-box, when I couldn't do it in the last tank with the same design. The answer lies in the order of construction. Before I fabricate the internal overflow-box in the new tank, I could insert the bulkheads first. That way, they would already be there, once the internal overflow-box gets built up around those prepositioned bulkheads. In doing this, I could have the flange side in the internal box.

I think that positioning the flange side of the bulkhead in the internal overflow-box would prevent leakage from the tank better then positioning the flange side of the bulkhead in the external overflow-box. Here's why: When testing the tank yesterday, I observed that the waterline in the external overflow-box did not rise very high during normal operation. However, the waterline of the internal overflow-box is always at maximum height, to the top of the weir. It seems that there is a greater risk of water leakage at the bulkheads in the internal overflow-box than in the external overflow-box because there is more water pressure at the bulkheads in the internal overflow-box. More pressure equals more opportunity to leak water at the bulkhead gasket/seals. Stated otherwise, there is more water weight pressing against the bulkheads in the internal overflow-box, under normal circumstances, than there is pressing against the bulkheads in the external overflow-box.

I think I'll try this new design, with the flange side of the bulkhead in the internal overflow-box. If I ever need to service or remove the bulkhead at the flange side, such that it needs to be removed from the internal overflow-box, I could always remove the glass weir of the internal overflow-box, to allow clearance to remove the bulkhead. It's a bit of a labor, to cut the silicone at the weir's junction with the floor of the internal overflow-box in such a future repair, but how often will I need to do such repairs? Not often, based on my past experience with two BeanAnimal tanks not requiring such repairs.

What do you all think about this plan? Thank you.
 
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