measuring board..edit

[finatic]

If you're taking a measuring board in a hot tub with hot chicks make sure you don't bring the 'SHORTY.'

[TexasDan]

I bought this new measure board and used it for the first time Saturday. It worked pretty well. Well built and very photogenic. I like that it is all one piece. I have the 40"x1/4" material. I bought the 321 sticker and sticks to it very well. It does stay a float long enough to grab it. This is a good measure board and recommended it for anyone.

Info. I found on it.
Acrylic Plastic
Unaffected by sun or salt spray
http://www.sdplastics.com/acrylic.html

[Norm]

Looks like a good one. AND...there are no screws to rust

[GO-Fish]

Im fairly certain I wasn't negative. Pretty sure I told him it looked good. Just stating a fact. I have worked with sign faces that expanded in the Florida heat. They were a little bit larger, but like I said, I don't know how much a piece this size would expand/contract. They were made from 1/4" acrylic. I still think its a nice board. By far the nicest looking one I have ever seen.

-- SCIENCE ALERT --

The expansion and contraction has little to do with the thickness of the material but rather the length or width. The distance something expands or contracts is a function of the coefficient of thermal expansion, the length and the temperature differential.

The general expansion formula can be expressed as:

dl = α Lo dt (1)

where

dl = expansion (m, inch)

Lo = length of pipe (m, inch)

dt = temperature difference (oC, oF)

α = linear expansion coefficient (m/moK, inch/inchoF)


Now the big variable is the Linear expansion coefficent and plastics have a wide range of this. For example extruded Acrylic has one of the largest linear expansion coefficient at 130x10-6 in/in oF or 0.000130 in/in oF so for a 40in long piece of excruded acrylic that is exposed to a 25 deg temperature differential (70f to 95f)

dl = 0.000130 x 40in x 25F = 0.13" or close to 1/8"

Where as a aluminum α = 12.3x10-6 in/inoF

dl = 0.0000123 x 40 x 25 = 0.0123 in

So that Red that measured 27" in the morning will measure 26 7/8" at mid day. Or conversly the red that measure 27" on the money on your board at the end of the day may measure 27 1/8" on the FWC board.

As I mentioned, plastics have a wide range of linear expansion coefficient, for example Sheet or cast Acrylic has a linear expansion coefficient or 45x10-6 in/ino, nearly 1/3 that of extruded Acrylic. So you need to find out what the material is to know what the difference is.

No, I don't know what the thermal expansion coefficent of a fish is, but it does have one.

Back to your normal programing.

[Tide1on]

So my kayak is not really 14 feet long?

[mudfish]

-- SCIENCE ALERT --

The expansion and contraction has little to do with the thickness of the material but rather the length or width. The distance something expands or contracts is a function of the coefficient of thermal expansion, the length and the temperature differential.

The general expansion formula can be expressed as:

dl = α Lo dt (1)

where

dl = expansion (m, inch)

Lo = length of pipe (m, inch)

dt = temperature difference (oC, oF)

α = linear expansion coefficient (m/moK, inch/inchoF)


Now the big variable is the Linear expansion coefficent and plastics have a wide range of this. For example extruded Acrylic has one of the largest linear expansion coefficient at 130x10-6 in/in oF or 0.000130 in/in oF so for a 40in long piece of excruded acrylic that is exposed to a 25 deg temperature differential (70f to 95f)

dl = 0.000130 x 40in x 25F = 0.13" or close to 1/8"

Where as a aluminum α = 12.3x10-6 in/inoF

dl = 0.0000123 x 40 x 25 = 0.0123 in

So that Red that measured 27" in the morning will measure 26 7/8" at mid day. Or conversely the red that measure 27" on the money on your board at the end of the day may measure 27 1/8" on the FWC board.

As I mentioned, plastics have a wide range of linear expansion coefficient, for example Sheet or cast Acrylic has a linear expansion coefficient or 45x10-6 in/ino, nearly 1/3 that of extruded Acrylic. So you need to find out what the material is to know what the difference is.

No, I don't know what the thermal expansion coefficient of a fish is, but it does have one.

Back to your normal programing.

I bet you got beat up a lot in school. .

[GO-Fish]

I bet you got beat up a lot in school. .

Nah, just had to deal with a similar issue for work plus Google is great if you know the right question to ask.