Sump design - Acrylic thickness question

[ckimble]

Question for the acrylic masters out there....

I am in the process of setting up a 280 system and am working on the design for the custom sump. I have a good feel for the layout, but am unsure of the thickness required for the pieces. The overall dimensions are 46"x24" and am wondering if 1/4" is adequate or if I need to use 3/8" for the sides. I will include the Google sketch-up drawing of my plan for reference and criticism.

Thanks in advance

Craig

[checkinhawk]

i would think 3/8" is fine but the height is really needed to give you a good answer.how tall do you plan on making the sump?

[ckimble]

Good point... guess I kind of forgot that one. The overall height is going to be 16" with the water level being around 9" while running. It should rise to around 12" with the return pump off. I was hoping to get by with 1/4" due to cost.

Thanks

[BeanAnimal]

I would use 3/8" but 1/4" would likely be ok. The 1/4" will bow a good bit due to the height and length of those panels. You will certainly need a 2" or so eurobrace. I built a similar sump and used 1/2". Actually I would use 1/2" on just about anything that size. It is nice and meaty with plenty of surface area for gluing. Overkill, but meaty.

[bchbum189]

3/8" will not cost much more than 1/4", i would do 3/8" with a euro.

[checkinhawk]

for 16" tall id deff use minimum 3/8" thick,and probably even eurobrace it.

[ckimble]

3/8" + euro-bracing it is then...

What about the fuge section, given those dimensions should that also be 3/8"?


Thanks all

[BeanAnimal]

That sump will be the better part of a sheet anyway... just buy the whole sheet.

[flyyyguy]

Id go 1/2". then you can lean on it with no worries. it will cost a little more upfront but you are going to be living with this for a while i imagine.

as well, eurobracing sucks for a sump IMO. its in the way.

i just put triangles on the corners and a 2" beam connecting the sides and the middle baffle. I can lean my fat *** on it anyehre i want with no concern

here is a pic of 1/2 of my 48x24 x 18" sump. ignore the color of he water...this was taken in the days to follow when i killed everything the sump took most of a sheet.

[waxy]

3/8" is a bit thick, Id go for 1/4 not too thin, not too thick.

Unless you have to make it a lot larger than a 50gallon capacity.

[bchbum189]

Originally posted by waxy
3/8" is a bit thick, Id go for 1/4 not too thin, not too thick.

Unless you have to make it a lot larger than a 50gallon capacity.

are you sure youre thinking of 3/8" and not 5/8"s? 1/4" is very thin for anything aquarium related, no matter how small the sump will be.

No one has ever complained about something being over built, you do hear the opposite complaint ALOT on hear though.

[BeanAnimal]

I certainly would not consider 3/8" to be thick!

1/4" material has very little contact area for solvent welding. It will also bow very easily and will need a fairly hefty eurobrace.

There is a slight bowing in my 1/2" 50 gallon sump!

[Acrylics]

Just a thought for ya; make the end of your fuge section a continuation of that first baffle. This will provide more reinforcement. Right now, your fuge's long panel will get torqed a little with any pressure differential, and (more importantly) it will make assembly easier and take some potential squareness issues out of the equation. Make the ends and first baffle all the same width, use another baffle as guide as to where to glue the end of the long pane onto the first baffle. (hoping this makes sense)
I think the consensus opinion of 3/8" is good, thicker is better if you can swing it. Could you make it from 1/4"? sure, but should you? not IMO. IMO sumps should be engineered to be full at all times. At some point it probably will be and then is not the time to test the strength of your joints. The importance of being able to sleep well at night cannot be underestimated

James

[BeanAnimal]

Sleeping well due to over engineering is always a good thing.

[ckimble]

Originally posted by Acrylics
Just a thought for ya; make the end of your fuge section a continuation of that first baffle. This will provide more reinforcement. Right now, your fuge's long panel will get torqed a little with any pressure differential, and (more importantly) it will make assembly easier and take some potential squareness issues out of the equation. Make the ends and first baffle all the same width, use another baffle as guide as to where to glue the end of the long pane onto the first baffle. (hoping this makes sense)
I think the consensus opinion of 3/8" is good, thicker is better if you can swing it. Could you make it from 1/4"? sure, but should you? not IMO. IMO sumps should be engineered to be full at all times. At some point it probably will be and then is not the time to test the strength of your joints. The importance of being able to sleep well at night cannot be underestimated

James

I think I get it... you mean shift the whole bubble trap assembly to the left so the far left baffle lines up with the end of the fuge?

Price difference here in Austin between 1/4 and 3/8 is about $100 a sheet. I can live with the extra expense to not worry about my sump flexing and splitting in the middle of the night.

I like my sleep....

Thanks all, I will post pictures once it is built

[snorvich]

My two new 42 gallon refugiums are both 3/8" with Eurobracing. 1/4 inch is just too flimsy in pressure situations. Water is pretty heavy. But I can certainly see going with 1/2 inch if the height is going to be much above 14 inches or so.

[ReefSparky]

Originally posted by BeanAnimal
It is nice and meaty with plenty of surface area for gluing. Overkill, but meaty.

when it comes to aquaria, meaty seems to be a global positive.

[kinktao]

I use to have a sump with euro bracing, hated it. gets in the way of hanging stuff like phosban reactors or what not.

[spazz]

Originally posted by kinktao
I use to have a sump with euro bracing, hated it. gets in the way of hanging stuff like phosban reactors or what not.

that is true but with out the bracing the sump will look pregnent and that causes alot of stress on the corner seams. if its not built properly it will start to split from the top down and water will be on the floor in a matter of months. bracing has alot more to do with the integrity of a sump than you realize. for a sump that is 16" tall 3/8" is fine for anything higher i would go with 1/2" the cost difference between 3/8" and 1/2" is about $50 its about the same difference for 1/4" to 3/8" $50 difference.

[flyyyguy]

Originally posted by spazz
that is true but with out the bracing the sump will look pregnent and that causes alot of stress on the corner seams. if its not built properly .

so spazz...jsut out of curiosity.......the way I braced my sump above is perfectly adequate is it not??

its actually 20" high(i said 18)........so 1/2"....48 x 24 x 20 with just bracing in the center and triangles on the corners.

I think its plenty burly enough...just curious what the pros think

[Dangles32]

Here is a link to a thickness calculator

http://www.garf.org/tank/buildtank.asp


According to this calculator 1/4" should be fine, if you use the calculator it will supply you with a cut sheet.

Hope this helps

Dangles

[BeanAnimal]

I would take the garf calculator with a grain of salt....

[ckimble]

Based on the feedback I have modified the plan slightly. I am dropping the overall height to 14" (mostly because it will be easier to get the skimmer in and out) and going with 3/8 throughout. I moved the bubble trap to be more of a structural piece, so hopefully with that + the bracing it should be plenty strong.