Eagler's Nest
General Category => Off Topics and General Interest => Topic started by: Steve on May 10, 2014, 04:11:22 PM
-
Hi Steve,
Today I got around to cutting a square foot of the paint sample and weighing it. the square foot of cloth with three coats of primer amd two coats of finish paint. the square foot of the sample weighed 1.31 OZ The square foot of cloth weighed 0.188 OZ The paint weighs 0.942 OZ now all one has to do is find out how many square ft. one has on there plane to know what the paint weighs, This is Latex paint. Waiting for the wind to die down to fly the Double Eagle. the Cabin Eagle is ready to run the engine. might make it next week.
Leonard
-
I was curious as to what the weight would be on my XL. Are your numbers off Boss? When I subtract 0.188 (cloth alone), from 1.31, (painted sample), I got 1.122 ounces, not 0.942 oz.
Using the 1.122 oz and the 120.3 sq. ft. wing area on the XL times 2, (both sides painted), I come out with 15.03 pounds of paint. WOW! That was quite a surprise to me because as a first time builder I never thought of that one item as being worth so much weight! No wonder you want us to build light. I'm cutting' down on mayonnaise and butter starting tonight! ;). Rich
-
I was curious as to what the weight would be on my XL. Are your numbers off Boss? When I subtract 0.188 (cloth alone), from 1.31, (painted sample), I got 1.122 ounces, not 0.942 oz.
Using the 1.122 oz and the 120.3 sq. ft. wing area on the XL times 2, (both sides painted), I come out with 15.03 pounds of paint. WOW! That was quite a surprise to me because as a first time builder I never thought of that one item as being worth so much weight! No wonder you want us to build light. I'm cutting' down on mayonnaise and butter starting tonight! ;). Rich
Rich:
Thanks for doing the math on that - we now know why Les' paint jobs are semitransparent...
Steve
-
I was curious as to what the weight would be on my XL. Are your numbers off Boss? When I subtract 0.188 (cloth alone), from 1.31, (painted sample), I got 1.122 ounces, not 0.942 oz.
Using the 1.122 oz and the 120.3 sq. ft. wing area on the XL times 2, (both sides painted), I come out with 15.03 pounds of paint. WOW! That was quite a surprise to me because as a first time builder I never thought of that one item as being worth so much weight! No wonder you want us to build light. I'm cutting' down on mayonnaise and butter starting tonight! ;). Rich
More math...
Using 120.3 ft.2 for the top of the wing fabric, multiplied by 2, I get 240.6 ft.2 of fabric for the top and bottom of the wings.
Paint them both on one side and each square foot of the paint weighs 1.122 oz.
That's 240.6 multiplied by 1.122... should equal 269.95 Oz. Using 16Oz per pound, I get 16.9 pounds of paint.
It's how I see it, numbers have never been my strong suit really however...
-
Hi Guys ,
If I am off my caculator is off I just ran the numbers once and did not check them. Will run them again. Leonard
-
More math...
Using 120.3 ft.2 for the top of the wing fabric, multiplied by 2, I get 240.6 ft.2 of fabric for the top and bottom of the wings.
Paint them both on one side and each square foot of the paint weighs 1.122 oz.
That's 240.6 multiplied by 1.122... should equal 269.95 Oz. Using 16Oz per pound, I get 16.9 pounds of paint.
It's how I see it, numbers have never been my strong suit really however...
That sounds reasonable. The number that has been tossed around for years in regard to total paint weight on an RV is 30-35 lbs. Wing area is similar on both planes.
-
More math...
Using 120.3 ft.2 for the top of the wing fabric, multiplied by 2, I get 240.6 ft.2 of fabric for the top and bottom of the wings.
Paint them both on one side and each square foot of the paint weighs 1.122 oz.
That's 240.6 multiplied by 1.122... should equal 269.95 Oz. Using 16Oz per pound, I get 16.9 pounds of paint.
It's how I see it, numbers have never been my strong suit really however...
yeah all that seems to pretty well jive with what I got from PolyFiber tech rep. According to him for a minimalist type fabric/paint job we can guesstimate 9-10.1 oz per square YARD. That's for the medium duty 2.7oz fabric with minimum polybrush, minimum polyspray, minimum tapes and a thin coat of polytone to finish it off. the Eagle fabric being 1.6oz will weigh 1.1oz per sq yard less or say about 8-10oz per sq yard. At 1.122oz per sq ft that's 10.1 oz per sq yard for the latex paint + the 1.6 oz for the fabric or 11.7oz per sq yard or as much as +3.7oz to as little as + 1.7oz per sq yard more than a a minimalist polyfiber job. and for us weight nuts that's a range of +46% to +17% more for a latex paint job over a polyfiber(8/3.7 and 10/1.7). well if all that is somewhere near correct that's a big weight increase for some of us but the cost is hands down for the latex. no doubt.
yall check my numbers if you will; as a final semi verification the polyfiber on the new one i'm working on is sposed to weigh 15# complete thru polytone. it's a little smaller but the # is in the ballpark
thx for the weights Boss, i been wondering what the diff might be. that's good stuff...now folks can make something of a weight comparison if they like
-
Well THATS why i didn't become an engineer. I had decided the square footage by 16 instead of the weight. Rich.:-[
-
Well THATS why i didn't become an engineer. I had decided the square footage by 16 instead of the weight. Rich.:-[
It takes a community... ;)
How did anybody build a plane when all they had was mail, telegraph, and telephone..?
-
I just finished preparing a couple test frames to take to Airventure to pass around at the Latex forum. They are wood frames, 12" square made from .75" square pine, covered with 1.8 oz uncertified cloth, glued with Stewarts Ekobond. I weighed them with a digital postal scale and was a little surprised with the numbers (perhaps my scale is off).
The bare frame - 4.9 oz.
Covered, glued, shrunk, trimmed - 5.4 oz. That actually includes 1.25 sq feet because I covered the sides (edges) also and that means that almost half of the area was glued. Doing the math, 1.8 oz per sq yd cloth is .2 oz per sq ft so my 1.25 sq ft piece should weigh .25 oz. That means the glue was an additional .25 oz. for a combined weight if .5 oz (5.4 - 4.9 = .5 oz)
The primed (6 thinned coats of Glidden Gripper and sanded), painted (4 thinned coats of Sherwin Williams and sanded), wet sanded, polished, and waxed final product weighed 5.9 oz. That's only .5 oz for 1.25 sq ft or .4 oz per foot. That's pretty light. I'll try to make some more measurements on other pieces in the future, but this is encouraging. I'll also have a friend check the finished weight on his postal digital scale to see if it's close to the same as mine.
Malcolm Morrison
wienerdogaero.com
-
Malcolm, that is good data. I'm glad you are on the forum because you are a good source of latex info. I found your PPT slides and webinar to be very informative as I researched latex paint.
On a related note, the webinar I presented on Building the XL has been viewed over 2300 times. The Eagle universe continues to expand. :)
-
Sam,
2300 times is amazing.
I guess it goes to show that there are a lot of us looking for fun, affordable flying. Great presentation by the way.
Malcolm
wienerdogaero.com
-
Sam,
2300 times is amazing.
I guess it goes to show that there are a lot of us looking for fun, affordable flying. Great presentation by the way.
Malcolm
wienerdogaero.com
Malcolm, your Latex webinar is running along at about the same clip.....Eagles and latex, good combination. :)