Correct.. if you get a scratch in poly you’re not gonna get it out.. you have 2 choices a flame “ugly” and a solvent to melt the plastic “ugly again” it can’t be sanded down with micro mesh or a fine wet sand and polished out.. it will to a extend but it’s distorted and swirly it will never look factory again it’s impossible to get a clear glassy look. It’s very easy to polish acrylic out to a glass finish with zero swirls.
The “wet side” expands in a convex direction, with concave on the dry side. This is the opposite direction that the water pushes on it. Also it is braced at 90 degree angles by the tether panels. This ads some stability.
Kind of a joke question really but Thanks! I figured the sides at 90 might add stability. That makes sense that the inside would bow out and outside in didnt 100% take that full in to account.
It’s weird how it works lol.. I’ve built plenty of kalk reactors and calcium reactors etc and the lids bolt down with thumb screws and are fine! I’ve even made replacement skimmer lids and they don’t curl up being round haha! But lay a square or rectangle piece of acrylic above water and the corners will curl up almost over night. Submerge a piece in water and it stays flat.
It was actually meant as a joke but you make a good point. I had just thought of that as a thickness thing. I had a 300g given to me years ago. When I first got it it was covered in coralline so I filled it up to test for leaks and clean it. It didnt bow anywhere dont remember the manufacturer I think sides and top were 1/2-5/8". Bottom was thicker then the rest. I've seen the sea clear and "cheaper" manufactured ones bow before seemed the acrylic was thinner like 3/8" for a 125. This dumb joke question has actually fielded me answers I didnt know I wanted or needed.
The submerged in water makes sense as both sides will "absorb" water equally.
Most acrylic tanks will bulge outward over time on large panels. Sometimes very noticeable sometimes not, but certainly still there. We can get into the math and determine how much, but I think that is beyond the scope of the conversation.
Hold it up and look through it into the light.Maybe we have different definitions. Below is through 0.250” polycarb (left), through scratched with 120grit (center), silver dollar sized spot polished (right). Looks pretty clear to me. There are several ways to polish poly both mechanically and chemically.
Can’t tell from that photo as there’s nothing behind it to focus on.. like I said it’s doable but it’s no where perfect or optically clear. Acrylic all day long that’s what they use on windshields for planes and fighter jets for a reason. Hold that over a black hood on a car a couple inches away and take a picture you’ll see the scratches and swirls.
Are you sure that is poly and not acrylic? Did you order a piece of polycarbonate or is tgis off something? And what did you use? As most buffers and clearers use fillers and thin flim layer to smooth and rid while not actually clearing it. Eitger way great job on clearing.Pollen season
Shooting through it focused on coral.
If you didnt use a chemical vapor or chemical type chemical or filler, this would be the first ever i could find or hear about for perfect clarity as I can not find nor have ever heard of polycarbonate being sanded or buffed completely clear using sanding or buffing without those, or is that what you did? I dont know your equipment or capabilites lol.
This piece is cut off a sheet I ordered personally but it works the same as pieces we have at the shop which are required to be certified as they go on aircraft… at Eglin. Use your imagination.
It looks okay but far from perfectly clear.. put that effort into a piece of acrylic and you’ll see what I’m saying. Try and polish the edges of that poly and see if you can pull the prismatic out of it like acrylic aPollen season
Shooting through it focused on coral.
