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- Here is a close up, unfortunately, it is a little blurry, but the measurement is roughly 8 - 1/4". As you can see, the bottom is bowed a little bit, between 1/4" and 3/8".
As I said though, all this weight is hung in the center, is about an extra 5-6 lbs greater than what is possible with water, and the sides only bowed just a touch.
All in all, I am not worried about the sink collapsing. As I said, this is worst case scenario, and then some.
I we only fill the sink 1/2 full, that would be about 60 lbs for the entire sink, instead of 119 lbs for a sink that is 10 x 15 x 22. But again, the sink slopes from 10" deep at one corner to about 8" at the shallow end.
No, I am not worried about failure. - Here we go. 18 lbs of screws being hung in the center of the bottom of the sink.
This actually has a few things wrong with it. First of all, in this pic, all of the 18 lbs is hung directly in the middle. With water, all the weight would be spread out across the entire length of 15 inches.
That means this torture test is way above what would be possible in real life.
Secondly, there would be several coats of Por 15 on top of the inside of the sink bottom, which would add strength, and a minimum of 3 not 2 coats of Epoxy on the bottom of the sink. - Now, before going on, let me say this. 18 lbs is waaaaayyy above what is actually possible with filling the sink with water. Why, you may ask? I am glad you did. Read on.
If we take a strip 2.5" wide by 15" long, and 10" high.
2.5 x 15 = 37.5 square inches. Multiply that by the 10" high, and we end up with 375 cubic inches. (Length x Width x Height).
We also know there are 231 cu inches in 1 gallon. 1 gallon of water weighs 8.33 lbs.
So, 375 divided by 231 = 1.6233 gallons of water. Multiply 1.6233 by 8.33 for the gallon of water and we end up with 13.522 lbs for weight of water for the 2.5" strip.
However, I am using 18 lbs or 33% more weight than what is even possible. Actually, only 1 corner is 10 inches deep. The center of the sink is only 9" deep so the actual possible weight in the center is about 12lbs. But that's okay. Let's overload it anyway. - I also included 7 lbs of screws in a plastic container. That makes a total of 18 lbs.
- Next is to get ready to add some weight. Here we have 11 lbs of Kreg screws in a gallon paint can.
- Next was to take a measurement of the distance between the bottom of the "sink", and the piece up top which will be used to lift this whole thing.
This measures just a hair shy of 8". - Here is the bottom of the "sink test", which as I said is about 2.5" by 15".
- I also glued in 2 pieces, only one layer though, of the extra oak pieces I used on the bottom of the sink. That make the bottom of this "about" the same thickness as the actual sink.
I say "about" because I only have 2 layers of Epoxy instead of 3, and I did not apply any Por 15 over the oak strips.
That means I have almost a replica of a 2.5" wide strip of what the sink is. - Ok. Here are the results of the sink pattern test. I know everyone has been sitting on the edge of their seats waiting for this, or not! Lol.
Either way, here it is.
I added a second layer of Epoxy to the bottom and the outside of what would be the walls of the sink. - Time to create a new "test" piece, since there was a question about the weight of the water in the sink, and my test procedure.
I glued together 3 pieces of plywood, which are the dimensions of the sink bottom and sides.
The corners look like this, with just Titebond glue. I will add some epoxy with fiberglass cloth just like I did with the sink, on the outside only. then I can add some weight to test the joints.
In all honesty, I don't expect a problem, but the test will give me some data to go by.
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