am i being a Sissy

Basile · #1 10-14-2013, 01:46 PM

Ok i have this rock work that weighs about 60lb, now i know are tanks holds thousands of pounds of water, i have a 150G . And i'll add sand and about 180 lb of rocks. But the sculpture i made has a "V" shape as you can see in the picture. I've built a support structure that is now failling and craking all over. That in mind i'm getting worried that the weight is too great on that one spot. If i cut the stands legs and put the structure directly on the sand, do you think its going to be ok, or just get rid of the whole feet all together and put the 16"X7" base rock directly on the glass be a better choice. 60Lb on an area 16"X7" is that too much for any glass. Any thoughs. Some of you must have done structure i'm waiting for your inputs thanks in advance. Maybe i'm over thinking this, just let me know.

Proteus · #2 10-14-2013, 02:34 PM

That's sweet

Consider drilling holes and using acrylic rod to hold together

Basile · #3 10-14-2013, 02:54 PM

Quote:

Originally Posted by Proteus

That's sweet

Consider drilling holes and using acrylic rod to hold together

I dont know if your joking but if you look at the picture thats exactly what i did actually nylon rods with nuts and further more its all cemented , the last one will have a stalactite comming down.

SoloSK71 · #4 10-14-2013, 03:14 PM

As long as the bottom glass of your tank is supported on plywood or similar you will be fine with that structure.

Charles

Proteus · #5 10-14-2013, 03:31 PM

I'm on iPhone so pics small. I though the support was a PVC piece.
Would be better if it were hidden though

Basile · #6 10-14-2013, 03:52 PM

Quote:

Originally Posted by Proteus

I'm on iPhone so pics small. I though the support was a PVC piece.
Would be better if it were hidden though

It will be hidden under 2 " of sand and the support right under the rock will be foamed and then sanded with resin epoxy. Nothing will show.

sphelps · #7 10-14-2013, 03:51 PM

The rock will obviously weight a lot less in water, the weight of the water displaced can be subtracted from the rock weight to get the apparent. The density of rock varies but it's often not much heavier than the water itself. Actually recently seen a piece of rock float in a tank

So basically don't be concerned about the weight of your structure on the glass, it's also much stronger than the plastic PVC frame you built.

The structure you made looks awesome btw.

Basile · #8 10-14-2013, 03:56 PM

Quote:

Originally Posted by sphelps

The rock will obviously weight a lot less in water, the weight of the water displaced can be subtracted from the rock weight to get the apparent. The density of rock varies but it's often not much heavier than the water itself. Actually recently seen a piece of rock float in a tank

So basically don't be concerned about the weight of your structure on the glass, it's also much stronger than the plastic PVC frame you built.

The structure you made looks awesome btw.

Thanks, i've got other sculptures on my thread , take a look; http://www.canreef.com/vbulletin/showthread.php?t=98466

ScubaSteve · #9 10-14-2013, 04:56 PM

Quote:

Originally Posted by Basile

I dont know if your joking but if you look at the picture thats exactly what i did actually nylon rods with nuts and further more its all cemented , the last one will have a stalactite comming down.

If you are using nylon rod, switch to acrylic and it will fix most of your problems. Nylon is not the best choice as it will begin to crack under the weight and will soften and swell in water.

Also, you can use physics to your advantage and add some weight on the opposite side from the overhang to reduce the torque (the bending force) on the rods. I did this on one of my old tanks and it worked like a charm. There are a few other things, like anchoring rods, that would also fix this and be easily hidden.

Basile · #10 10-14-2013, 06:16 PM

So my sculpture is finished, just have to rebuild the support with 1" pvc which i got as you can see i just need elbows ,lol. Then just got to hide those nuts and put it in the tank with a plexi glass in the bottom. The sculpture is 36" longX20"wideX 20" hight. My tank is 21" hight, but the structure was suppose to be built with 1/2" pvc now its with 1" so my last rock will be floating, i'll put a mini palm tree and a lodge for the snails.

At the end of the ramp a stalactite will come down.