Help with a geometry problem

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jcraigie
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Help with a geometry problem

Post by jcraigie »

I want to put a wood bottom under my pool. Using 3/4" 4' x 8' treated plywood with 2 x 4's to hold the pieces together. It's a 24' round pool (24' across). Using the largest possible piece's how would you piece this together? Any and all ideas are appreciated.
1984 Mark V 500 and an early 1954 greenie. jointer, belt sander, bandsaw, jigsaw, planner.

Jeff
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JPG
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Post by JPG »

jcraigie wrote:I want to put a wood bottom under my pool. Using 3/4" 4' x 8' treated plywood with 2 x 4's to hold the pieces together. It's a 24' round pool (24' across). Using the largest possible piece's how would you piece this together? Any and all ideas are appreciated.

You will not gain much by making it 'round'.

However make it an octagon with 10' sides would be 24' 3.5" across.(9'11'' = 23'11+")

Requires 17 4x8 sheets with scrap totaling 1' x 2'(4 triangular pieces 1' x 1' x 16.9)".

I would frame it on 2' centers.
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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beeg
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Post by beeg »

How many gallons of water does your pool hold? Take that number times 8.3 and that will be the number of pounds on the plywood.
SS 500(09/1980), DC3300, jointer, bandsaw, belt sander, Strip Sander, drum sanders,molder, dado, biscuit joiner, universal lathe tool rest, Oneway talon chuck, router bits & chucks and a De Walt 735 planer,a #5,#6, block planes. ALL in a 100 square foot shop.
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beeg
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Post by beeg »

How many gallons of water does your pool hold? Take that number times seven and that will be the number of pounds on the plywood.
SS 500(09/1980), DC3300, jointer, bandsaw, belt sander, Strip Sander, drum sanders,molder, dado, biscuit joiner, universal lathe tool rest, Oneway talon chuck, router bits & chucks and a De Walt 735 planer,a #5,#6, block planes. ALL in a 100 square foot shop.
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Bob
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mrhart
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Post by mrhart »

These guys are such know-it-alls :D
Yea.. I knew all that stuff too, I was thinkin more like "just use one crosscut of a really big tree"
Ha, one piece--No scrap! :D
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Post by pessen »

I agree that making a round base to exactly fit the base of your pool won't save you much, and will make it harder to frame in with 2x4's or whatever you decide to use.

Attached is a power point of two configurations, first where you make it exactly round, and second where you do the 10' octagon. The second seems to make more sense as far as ease of framing it in because you have all straight edges. Attached are screengrabs of two powerpoint visualizations. The lightest pink areas are where the cutoffs would be. The drawings are to scale.

Hope this helps.

pessen

[ATTACH]13023[/ATTACH]

[ATTACH]13024[/ATTACH]
Attachments
Pool_Base_Circle.jpg
Pool_Base_Circle.jpg (47.99 KiB) Viewed 1298 times
Pool_Base_Octagon.jpg
Pool_Base_Octagon.jpg (54.5 KiB) Viewed 1298 times
1981 Mark V, bought used in Feb. 2011
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jcraigie
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Post by jcraigie »

Pessen -That's perfect! Thank you.

One giant slice of tree, hmmm, let me know when you find that ok:rolleyes:

The wood will be placed on top of a sand base, with the sheets of plywood butted together over 2 x 4's so the weight distribution should be ok.

beeg - actually water weighs 8.3 pounds
1984 Mark V 500 and an early 1954 greenie. jointer, belt sander, bandsaw, jigsaw, planner.

Jeff
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JPG
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Post by JPG »

pessen wrote:I agree that making a round base to exactly fit the base of your pool won't save you much, and will make it harder to frame in with 2x4's or whatever you decide to use.

Attached is a power point of two configurations, first where you make it exactly round, and second where you do the 10' octagon. The second seems to make more sense as far as ease of framing it in because you have all straight edges. Attached are screengrabs of two powerpoint visualizations. The lightest pink areas are where the cutoffs would be. The drawings are to scale.

Hope this helps.

pessen

[ATTACH]13023[/ATTACH]

[ATTACH]13024[/ATTACH]

Crudely edited, but my thoughts! Duplicate bottom right corner for all four corners.

[ATTACH]13025[/ATTACH]
Attachments
Pool_Base_Octagon 2.jpg
Pool_Base_Octagon 2.jpg (52.1 KiB) Viewed 1275 times
╔═══╗
╟JPG ╢
╚═══╝

Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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