Center glass brace replace or not?

[rpkneumann]

I’m restoring an old 150 gallon Oceanic tank and tried cleaning a gigantic glass center brace which is completely calcified. 20 years of Texas water.
I threw every legal cleaning agent on the glass but the final advice from a local glass store was to give up and replace.

My head is spinning after researching literally 100s of Internet opinions , YouTube videos of what todo about replacing top bracing. Some say don’t try to replace the center brace it will always fail. Others say replace it with Aluminium braces at least 2 inches wide and some say 1/2 inch glass is thick enough to run rimless. Some even suggest to install eurobracing instead.

I’m an engineer and believe that the manufacturer had good reasons and sound calculations to install a 14 inch wide 1/2 thick center brace in this 48x24x30 tank.

Seems to me that the only sound option would be trying to replace the glass with the exact same size and location.

Current glass prices would make this a $240 item plus hours of silicon cleaning.

Has anybody replaced this type of center brace successfully?
What are the pitfalls and what would I need to avoid?

Didn’t come across instructions on how todo this successfully.

Any advice ?

 

[ca1ore]

I have the same tank. Used for many years as a display, now serves as my sump. Did you try a very sharp single edge razor?

My solution was to grind a hole in the brace to allow a kessil 360 to shine through.

 

[rpkneumann]

Yep, tried sharp razors, hard and soft scrapers. Scrubbers and a ton of elbow grease.
The glass people told me the only way to get calcium which has eaten itself that deep would be polishing the glass with a glass planar machine.
Would mean I cut it out.
Debating that. But success rate for replacement seems low. Started a new thread about that asking for decision support.
Plus it will cost around $240 for the glass alone.

 

[Sassafras]

I also had this same tank years ago. Really well built, but that center brace, ugh! I considered replacing it with aluminum braces, but ended up selling it. I think I would consider the aluminum brace option.

 

[moretor1]

Yep, tried sharp razors, hard and soft scrapers. Scrubbers and a ton of elbow grease.
The glass people told me the only way to get calcium which has eaten itself that deep would be polishing the glass with a glass planar machine.
Would mean I cut it out.
Debating that. But success rate for replacement seems low. Started a new thread about that asking for decision support.
Plus it will cost around $240 for the glass alone.

Is it on the top or bottom of the pane?

Are you comfortable handling strong acids?
Muriatic acid would be my first choice but EDTA is made specifically for stripping iron and calcium ions

Ideally you want a way to soak the spots for an extended period of time. If it's the top you could just make a wall with some corner clamps and pour a very small layer where you're working

 

[rpkneumann]

Moretor
I came to the replacing center brace topic via a previous thread
https://www.reef2reef.com/threads/frustration-can’t-get-calcified-glass-clean.1055627/ I tried everything legal….

 

[rpkneumann]

S

I also had this same tank years ago. Really well built, but that center brace, ugh! I considered replacing it with aluminum braces, but ended up selling it. I think I would consider the aluminum brace option.

Sassafras
I thought a while about the aluminium brace. Easy to manufacture and can just be slipped over the existing frame. Spray paint it every few years or learn how to do powder coating at home

The current brace is 14" wide.
Yes, its silicon attached but I can't visualize that a 2" aluminium brace could capture the same bowing forces. I have always been bad with visualizing technical mechanics.

The question I have is would that actually help with the distribution of forces?

I asked Aquenon as a one time builder of these kind of monster tanks, but have not heard back from them.

 

[BeanAnimal]

The width of the brace provides for bonding area. The tensile strength of the aluminum would be more than enough. If you are concerned about point loading then simple make the “clamping” edges 14” wide to mimic the area supported by the glass. Or use two aluminum braces 14” apart, or even connect them together as a single unit.

 

[DCR]

It is really difficult to get anything between the glass panes and cut it out. Razor blades are generally too wide. I have heard that piano wire works, but you have to deal with the plastic rim. It is also difficult to remove. I would probably just leave it. I does not really look that bad and I have found that salt on my glass lids blocks surprisingly little light. I do love those old Oceanic tanks. They were built strong.

 

[rpkneumann]

The width of the brace provides for bonding area. The tensile strength of the aluminum would be more than enough. If you are concerned about point loading then simple make the “clamping” edges 14” wide to mimic the area supported by the glass. Or use two aluminum braces 14” apart, or even connect them together as a single unit.

This makes sense to me.
I’ll do my plumbing work next and fill it to see if I have more problems..
I have just drilled the tank to accommodate your names sake plumbing drains using an outside overflow box.

That leak test will show me how the old glass brace behaves with water since some claimed it wouldn't effect the light going through.
If negative, out it will go and an Aluminium brace will go in.

 

[rpkneumann]

It is really difficult to get anything between the glass panes and cut it out. Razor blades are generally too wide. I have heard that piano wire works, but you have to deal with the plastic rim. It is also difficult to remove. I would probably just leave it. I does not really look that bad and I have found that salt on my glass lids blocks surprisingly little light. I do love those old Oceanic tanks. They were built strong.

I’ll fill the tank for a leak test and check it out.

 

[rpkneumann]

Rim/Center brace question asked differently:
Can I:
- Leave brace or replace with 2"-3" (2/8 thick) wide glass brace.
- Remove trim
- Add glass triangles (3" x 3") (2/8" thick) for support?

It seems nobody can really explain the mechanical function and forces in a top trim with a tank also having a brace.

I've done lots of reading and taking to my LFS. and several tank manufacturers who all give different answers.
The LFS believes replacing the center with a 2" glass brace would suffice. If glass not available then a aluminium brace. He wasn't sure about the trim, even though they have replaced braces in their own tanks but never needed to take off the trim.

 

[BeanAnimal]

Rim/Center brace question asked differently:
Can I:
- Leave brace or replace with 2"-3" (2/8 thick) wide glass brace.
- Remove trim
- Add glass triangles (3" x 3") (2/8" thick) for support?

It seems nobody can really explain the mechanical function and forces in a top trim with a tank also having a brace.

I've done lots of reading and taking to my LFS. and several tank manufacturers who all give different answers.
The LFS believes replacing the center with a 2" glass brace would suffice. If glass not available then a aluminium brace. He wasn't sure about the trim, even though they have replaced braces in their own tanks but never needed to take off the trim.

Hi - I am not sure what you are actually struggling with but will try to help.

The center brace prevents the two long sides from bowing outward. That bowing puts stress on the panels and shear stress on the vertical seams.

The top trim may add some stiffness to the system as well as protecting the top (weak) edge of the glass from chipping or fracture.

The WIDTH of that glass brace provide both tensile strength and bonding area. The wider the brace, the larger the bonding area.

Likewise, the wider the bonding area the less chance of buckling there is (due to outward pressure) on the long panels.

We can do all kinds of math to figure out the stress on the panels, braces and adhesives... but why?

Either replace the brace with one of similar width and thickness. This gets you back to the designed parameters....

OR replace the brace with another material whos tensile strength is comparable or greater and instead of working about "bonding area" you make the brace a "clamp" style. To get back to baseline for "buckling" you make the clamping legs of the new brace at least as wide as the adhered area of the current brace.

Asking an LFS for engineering advice... Unless they slept at a Holiday Inn last night...

 

[FUNGI]

Have you tried CLR? It works great....(at least for me)

 

[DCR]

The trim does not add any strength. It just protects the edge of the glass from impacts and provides a support rim for any lids. For what I have seen of the current Planet tanks they seem to use about a 3" wide x 1/2" thick cross brace every 24 inches. The 14" width is overly conservative, but I would probably make it 4-6" wide if for my own comfort. I would definitely use 1/2" thick glass for greater tensile strength. A very simple calculation but to put it in perspective, there is about 800 lbs of total force on your front and back panels from the water.

 

[BeanAnimal]

I assume this is similar to your tank

A simple clamp type brace cold be easily fabricated from bar/angle stock. Use Stainless or aluminum. Braze or weld or screw and bolt. The tensile strength will exceed that of glass. Silicone it in place so that it does not move or pop off.

You size this to go over the trim or cut the trim. If you cut the trim, a silicone bead between the angle and glass will provide a small buffer for slight movement and shock.

 

[BeanAnimal]

The trim does not add any strength.

I do agree in the big picture (as posted above) but pedantically, the trim is a 3 dimension extrusion that is adhered to the top edge. It does provide some calculable stiffness... needed or not.

 

[DCR]

I do agree in the big picture (as posted above) but pedantically, the trim is a 3 dimension extrusion that is adhered to the top edge. It does provide some calculable stiffness... needed or not.

Technically you are right - it is not zero, but I have taken the trim off an Oceanic tank, and I can easily bend it with my hands and arms. Maybe if it is held in the correct plane with silicone to take advantage of the L-shape, but I doubt it provides much strength.

 

[rpkneumann]

I assume this is similar to your tank

A simple clamp type brace cold be easily fabricated from bar/angle stock. Use Stainless or aluminum. Braze or weld or screw and bolt. The tensile strength will exceed that of glass. Silicone it in place so that it does not move or pop off.

You size this to go over the trim or cut the trim. If you cut the trim, a silicone bead between the angle and glass will provide a small buffer for slight movement and shock.

Thank you for the explanation /
Wasn't ready todo a lot of math but my engineering heart just wanted to understand it better.
Yes, this is my tank. A 2005 Oceanic.
This thread pretty much confirmed what i thought the top rims function is. I was insecure if i can take the trim off.
I like the fabricated frame.
Since the metal tensile strength is great, would I be able to get away with one 3" metal strip shaped like a u?

 

[Malum Argenteum]

Current glass prices would make this a $240 item

14" x 24" in 1/2", tempered or annealed, is less than $100 shipped from One Day Glass. Not sure that helps your decision about what to do, but it might.