Anyone on here got any idea of the approximate water capacity of a full width..ie...across the van width.... section of 100mm downpipe sealed up for the purpose?? I,m thinking that it could be made into a grey water tank if its capacity is enough.TIA.
Cheers Keith
brickies said
04:05 PM Sep 10, 2017
Diameter squared x .8 by length multiplied x 1000 will give litres . So 100mm pipe x 2.2 metres . (.1x .1 x .8 x 2.2 x1000 ) will give litres , equals 17.6 litres , So length of 100 ml pipe 2.2 metres long will hold 17.6 litres .
KJB said
04:13 PM Sep 10, 2017
Probably more importantly, about an extra 18 kgs.
KB
rockylizard said
05:08 PM Sep 10, 2017
KJB wrote:
Probably more importantly, about an extra 18 kgs.
KB
Gday...
But only after 18Kgs (17.6ltrs) is turned into grey water from the main water tank which will now be 18Kg (17.6Ltr) lighter negating any increase in overall weight ... just a transfer of weight.
cheers - John
toglhot said
05:23 PM Sep 10, 2017
Bit of a bugger to empty though, since most seem to think that gray water is toxic. I water the plants in my garden with it at home.
Keith P said
06:12 PM Sep 10, 2017
Hmmm...that aint a lot hey. The idea was only fact finding really....as the genuine Jayco is approx. 60 litres....and not very expensive if fitted at time of building.
So I guess we will be going that way now..... but I had an idea that it may have been cheaper to retrofit it later...but not feasible unless I used 6 inch stormwater pipe instead....and there is no room for that under the van !!
Thanks for everyone for their input and maths here.
Cheers Keith
brickies said
07:18 PM Sep 10, 2017
A 150 ml pipe would hold 39.6 litres , 2/100ml pipes would hold 35.2 litres .
Cupie said
10:08 PM Sep 10, 2017
On mine I can run a single length of 100ml right down most of the length of the van between the slotted frame & the axles giving me a 47l capacity (using the pi x R squared x length x 1000 formula .. thanks for that, takes me back to my high school days some 60 years ago). Might just use some shorter lengths closer to the axle group.
Got all the bits from my plumber son's spare parts bin.
The 100ml has a thicker wall than the 90ml storm water stuff so should be more suitable.
Might get round to it one of these days.
ps We too have been using our grey water from the washing machine to water the Lime tree at home for>10 years. We do use the NP powder though.
I fitted 2 lengths of 6 inch PVC stormwater pipe under our caravan, linked together and capped at both ends, one is slightly longer by about 3 inches than the other due to other fittings, they fit between the chassis rails at the rear. My calculations were I can hold 52 litres. I have a ball valve so I can divert from ground to grey water tanks, included a breather, and have a Camlok fitting to drain when necessary.
Works well for us, got one pice of pipe for nothing, the other I paid $5-00 for, the most expensive parts were the end caps at $19-00 each
Yes and the formulae for finding the volume of a cylinder is
pi x Radius squared x length
so there you go ... I just hope that you took the inside measurements.
and if you really want to nit prick, pi is just a bit more that 3.14 but we all know that don't we
eg.
ONE MILLION DIGITS OF PI
3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067982148086513282306647093844609550582231725359408128481117450284102701938521105559644622948954930381964428810975665933446128475648233786783165271201909145648566923460348610454326648213393607260249141273724587006606315588174881520920962829254091715364367892590360011330530548820466521384146951941511609433057270365759591953092186117381932611793105118548074462379962749567351885752724891227938183011949129833673362440656643086021394946395224737190702179860943702770539217176293176752384674818467669405132000568127145263560827785771342757789609173637178721468440901224953430146549585371050792279689258923542019956112129021960864034418159813629774771309960518707211349999998372978049951059731732816096318595024459455346908302642522308253344685035261931188171010003137838752886587533208381420617177669147303598253490428755468731159562863882353787593751957781857780532171226806613001927876611195909216420198938095257201065485863278865936153381827968230301952035301852968995773622599413891249721775283479131515574857242454150695950829533116861727855889075098381754637464939319255060400927701671139009848824012858361603563707660104710181942955596198946767837449448255379774726847104047534646208046684259069491293313677028989152104752162056966024058038150193511253382430035587640247496473263914199272604269922796782354781636009341721641219924586315030286182974555706749838505494588586926995690927210797509302955321165344987202755960236480665499119881834797753566369807426542527862551818417574672890977772793800081647060016145249192173217214772350141441973568548161361157352552133475741849468438523323907394143334547762416862518983569485562099219222184272550254256887671790494601653466804988627232791786085784383827967976681454100953883786360950680064225125205117392984896084128488626945604241965285022210661186306744278622039194945047123713786960956364371917287467764657573962413890865832645995813390478027590099465764078951269468398352595709825822620522489407726719478268482601476990902640136394437455305068203496252451749399651431429809190659250937221696461515709858387410597885959772975498930161753928468138268683868942774155991855925245953959431049972524680845987273644695848653836736222626099124608051243884390451244136549762780797715691435997700129616089441694868555848406353422072225828488648158456028506016842739452267467678895252138522549954666727823986456596116354886230577456498035593634568174324112515076069479451096596094025228879710893145669136867228748940560101503308617928680920874760917824938589009714909675985261365549781893129784821682998948722658804857564014270477555132379641451523746234364542858444795265867821051141354735739523113427166102135969536231442952484937187110145765403590279934403742007310578539062198387447808478489683321445713868751943506430218453191048481005370614680674919278191197939952061419663428754440643745123718192179998391015919561814675142691239748940907186494231961567945208095146550225231603881930142093762137855956638937787083039069792077346722182562599661501421503068038447734549202605414665925201497442850732518666002132434088190710486331734649651453905796268561005508106658796998163574736384052571459102897064140110971206280439039759515677157700420337869936007230558763176359421873125147120532928191826186125867321579198414848829164470609575270695722091756711672291098169091528017350671274858322287183520935396572512108357915136988209144421006751033467110314126711136990865851639831501970165151168517143765761835155650884909989859982387345528331635507647918535893226185489632132933089857064204675259070915481416549859461637180270981994309924488957571282890592323326097299712084433573265489382391193259746366730583604142813883032038249037589852437441702913276561809377344403070746921120191302033038019762110110044929321516084244485963766983895228684783123552658213144957685726243344189303968642624341077322697802807318915441101044682325271620105265227211166039666557309254711055785376346682065310989652691862056476931257058635662018558100729360659876486117910453348850346113657686753249441668039626579787718556084552965412665408530614344431858676975145661406800700237877659134401712749470420562230538994561314071127000407854733269939081454664645880797270826683063432858785698305235808933065757406795457163775254202114955761581400250126228594130216471550979259230990796547376125517656751357517829666454779174501129961489030463994713296210734043751895735961458901938971311179042978285647503203198691514028708085990480109412147221317947647772622414254854540332157185306142288137585043063321751829798662237172159160771669254748738986654949450114654062843366393790039769265672146385306736096571209180763832716641627488880078692560290228472104031721186082041900042296617119637792133757511495950156604963186294726547364252308177036751590673502350728354056704038674351362222477158915049530984448933309634087807693259939780541934144737744184263129860809988868741326047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etc. ad infinitum ha ha ... just having a little joke .... edit .. Have you counted the digits? ...
-- Edited by Cupie on Monday 11th of September 2017 10:52:55 AM
brickies said
01:22 PM Sep 11, 2017
Dorian if you look at my formula it's diameter squared, Not Radius squared , I used theses formulas when in the fire service using diameter pi is .7854 , But on the fire ground always used .8 , And when you were pumping 1000 lts per minute that's close enough . We didn't have mister google in those day had to use our brain .
Cupie said
01:43 PM Sep 11, 2017
brickies wrote:
Dorian if you look at my formula it's diameter squared, Not Radius squared , I used theses formulas when in the fire service using diameter pi is .7854 , But on the fire ground always used .8 , And when you were pumping 1000 lts per minute that's close enough . We didn't have mister google in those day had to use our brain .
-- Edited by Cupie on Monday 11th of September 2017 01:45:42 PM
rockylizard said
01:51 PM Sep 11, 2017
Gday...
GEEZ you lot ... this is the only pie I am interested in ....
Cheers - John
brickies said
02:15 PM Sep 11, 2017
Square one are the best value
Dougwe said
03:15 PM Sep 11, 2017
rockylizard wrote:
Gday...
GEEZ you lot ... this is the only pie I am interested in ....
Cheers - John
Nearly Rocky
dorian said
07:32 AM Sep 12, 2017
I guess I shouldn't be surprised at the response in this thread. It goes to the crux of the reason that many employers believe old folks to be unemployable, namely that they cannot accept that there may be a different, possibly better, way to tackle a task that they have been doing for decades.
Notice that I didn't say that my approach was better, or that any of the proposed solutions were incorrect or inferior. I merely offered an alternative method.
As for pi, I don't need to know that it is a transcendental number that has no finite representation in the decimal number system. I just need to know that pi = "pi" and let Google's calculator handle the rest.
If anyone had bothered to follow the link I provided, they would have seen the obvious utility of this tool. I also provided the sample output, verbatim, to illustrate the importance of parentheses, and the precision of the calculator.
As for computational aids, they can be useful, especially when one doesn't understand the underlying concepts and is totally dependent on rote learning. However, I prefer not to clutter my brain with things I don't need. Instead, all I need to remember is that volume equals area times length. This applies equally to a cylindrical pipe as it does to a length of timber or a stick of licorice.
So ...
volume = cross-sectional area x length = area of circle x length = pi x radius squared x length = pi x (diameter / 2) squared x length = (pi / 4) x diameter squared x length
The last line illustrates the reason for the "0.8" in the rule of thumb calculation.
Furthermore, I can mix up the units of length and volume in any way I like. I don't need to remember that the diameter is in millimetres and the length in metres, nor do I need to remember to apply a conversion factor of 1000. Google's calculator does all that.
pi x ((6 inches / 2) squared) x 2.2 m in litres pi x (((6 inches) / 2) squared) x (2.2 m) = 40.1312323 litres
pi x ((6 inches / 2) squared) x 2.2 m in US gallons pi x (((6 inches) / 2) squared) x (2.2 m) = 10.60155 US gallons
pi x ((6 inches / 2) squared) x 2.2 m in firkins pi x (((6 inches) / 2) squared) x (2.2 m) = 0.980848151 firkins
pi x ((6 inches / 2) squared) x 2.2 m in cubic cubits pi x (((6 inches) / 2) squared) x (2.2 m) = 0.419917362 cubic cubits
Some care needs to be taken to ensure that Google evaluates the expression in the correct order.
pi x ((50 mm) squared) x (2.2 m) = 17.2787596 litres
Cupie said
10:13 AM Sep 12, 2017
dorian wrote:
I guess I shouldn't be surprised at the response in this thread. It goes to the crux of the reason that many employers believe old folks to be unemployable, namely that they cannot accept that there may be a different, possibly better, way to tackle a task that they have been doing for decades.
Notice that I didn't say that my approach was better, or that any of the proposed solutions were incorrect or inferior. I merely offered an alternative method.
As for pi, I don't need to know that it is a transcendental number that has no finite representation in the decimal number system. I just need to know that pi = "pi" and let Google's calculator handle the rest.
If anyone had bothered to follow the link I provided, they would have seen the obvious utility of this tool. I also provided the sample output, verbatim, to illustrate the importance of parentheses, and the precision of the calculator.
As for computational aids, they can be useful, especially when one doesn't understand the underlying concepts and is totally dependent on rote learning. However, I prefer not to clutter my brain with things I don't need. Instead, all I need to remember is that volume equals area times length. This applies equally to a cylindrical pipe as it does to a length of timber or a stick of licorice.
So ...
volume = cross-sectional area x length = area of circle x length = pi x radius squared x length = pi x (diameter / 2) squared x length = (pi / 4) x diameter squared x length
The last line illustrates the reason for the "0.8" in the rule of thumb calculation.
Furthermore, I can mix up the units of length and volume in any way I like. I don't need to remember that the diameter is in millimetres and the length in metres, nor do I need to remember to apply a conversion factor of 1000. Google's calculator does all that.
pi x ((6 inches / 2) squared) x 2.2 m in litres pi x (((6 inches) / 2) squared) x (2.2 m) = 40.1312323 litres
pi x ((6 inches / 2) squared) x 2.2 m in US gallons pi x (((6 inches) / 2) squared) x (2.2 m) = 10.60155 US gallons
pi x ((6 inches / 2) squared) x 2.2 m in firkins pi x (((6 inches) / 2) squared) x (2.2 m) = 0.980848151 firkins
pi x ((6 inches / 2) squared) x 2.2 m in cubic cubits pi x (((6 inches) / 2) squared) x (2.2 m) = 0.419917362 cubic cubits
Some care needs to be taken to ensure that Google evaluates the expression in the correct order.
pi x ((50 mm) squared) x (2.2 m) = 17.2787596 litres
Ha ha .... Love it ...
Though my experience differs from the opening statement.
I found that the new ones on the block usually came up with a 'new way' of doing things dressed up with a confusing range of terms. We oldies were often able to provide evidence of the 'new approach' having been tried unsuccessfully in the past. Often they were out to add another page to their CV before moving on before the results of their innovations were evident.
Mind you it is over 20 years since I retired so perhaps things have changed.
Having said that, I frequently observe people doggedly following the perennial 'Calf Path'. Which perhaps supports dorian's statement.
So there you go.
Time for a cuppa before getting the van ready for a short trip up to The Carnival Of Flowers.
Now what was this thread about?
Jaahn said
10:40 AM Sep 12, 2017
Hi
Just to provide another look at the inexact PII. In decimal form it is inexact, BUT in ratio form it is not. 22/7 is exact and I use that all the time when I do a simple calc for a circle. Easy to remember too
The ancients who found these old relationships never used decimals but mostly saw it all in ratios. Easy to understand too.
Jaahn
dorian said
11:44 AM Sep 12, 2017
Jaahn wrote:
Just to provide another look at the inexact PII. In decimal form it is inexact, BUT in ratio form it is not. 22/7 is exact ...
No, it isn't.
7 x (22/7) = 22
7 x pi = 21.9911486
Jaahn said
12:40 PM Sep 12, 2017
dorian wrote:
Jaahn wrote:
Just to provide another look at the inexact PII. In decimal form it is inexact, BUT in ratio form it is not. 22/7 is exact ...
No, it isn't.
7 x (22/7) = 22
7 x pi = 21.9911486
By whose calculation ??
Jaahn
dorian said
04:38 PM Sep 12, 2017
Jaahn wrote:
dorian wrote:
Jaahn wrote:
Just to provide another look at the inexact PII. In decimal form it is inexact, BUT in ratio form it is not. 22/7 is exact ...
1. (Mathematics) a device for performing mathematical calculations, esp an electronic device that can be held in the hand
Hewy54 said
05:40 PM Sep 12, 2017
Bit of a chuckle reading all this.
My dad always used to tell me "keep your mouth shut that way people will only THINK you're stupid"
Cupie said
05:49 PM Sep 12, 2017
Hi Keith (OP) ..
Don't mind Hewy54 ... or his Father.
I hope we put you right.
Dick0 said
06:02 PM Sep 12, 2017
I was looking at making one up out of plastic pipe but space did not permit...however, after measuring, this fitted just nicely and cost about $60.00 from Ebay plus other cheap connections from Bunnings.
What to say, I am gutted. My old maths teacher told us that 22/7 was exact and now I find it is not Out by an enormous 4 in 10000 (approximately of course). I will have to go and find his last resting place and spit on his memory. Who can you trust these days
mea culpa, mea culpa !
Jaahn
Peterpan said
07:39 PM Sep 12, 2017
Opinion without 3.14 is an onion.
I'll run now.
Keith P said
08:46 PM Sep 12, 2017
Cupie wrote:
Hi Keith (OP) ..
Don't mind Hewy54 ... or his Father.
I hope we put you right.
Yep...waaaay back. Found out enough from the paddock variety calculations first up to work out it aint gunna work....so will get the grey water system added as van is being built.
Anyone on here got any idea of the approximate water capacity of a full width..ie...across the van width.... section of 100mm downpipe sealed up for the purpose?? I,m thinking that it could be made into a grey water tank if its capacity is enough.TIA.
Cheers Keith
Probably more importantly, about an extra 18 kgs.
KB
Gday...
But only after 18Kgs (17.6ltrs) is turned into grey water from the main water tank which will now be 18Kg (17.6Ltr) lighter negating any increase in overall weight ... just a transfer of weight.
cheers - John
Hmmm...that aint a lot hey. The idea was only fact finding really....as the genuine Jayco is approx. 60 litres....and not very expensive if fitted at time of building.
So I guess we will be going that way now..... but I had an idea that it may have been cheaper to retrofit it later...but not feasible unless I used 6 inch stormwater pipe instead....and there is no room for that under the van !!
Thanks for everyone for their input and maths here.
Cheers Keith
On mine I can run a single length of 100ml right down most of the length of the van between the slotted frame & the axles giving me a 47l capacity (using the pi x R squared x length x 1000 formula .. thanks for that, takes me back to my high school days some 60 years ago). Might just use some shorter lengths closer to the axle group.
Got all the bits from my plumber son's spare parts bin.
The 100ml has a thicker wall than the 90ml storm water stuff so should be more suitable.
Might get round to it one of these days.
ps We too have been using our grey water from the washing machine to water the Lime tree at home for>10 years. We do use the NP powder though.
I use Google's calculator.
http://www.google.com.au/search?q=pi+x+((150+mm+/+2)+squared)+x+2.2+m+in+litres
pi x (((150 mm) / 2) squared) x (2.2 m) = 38.8772091 litres
No, pi = 3.14, not .785.
http://www.google.com.au/search?q=pi
Gooday,
I fitted 2 lengths of 6 inch PVC stormwater pipe under our caravan, linked together and capped at both ends, one is slightly longer by about 3 inches than the other due to other fittings, they fit between the chassis rails at the rear. My calculations were I can hold 52 litres. I have a ball valve so I can divert from ground to grey water tanks, included a breather, and have a Camlok fitting to drain when necessary.
Works well for us, got one pice of pipe for nothing, the other I paid $5-00 for, the most expensive parts were the end caps at $19-00 each
Yes and the formulae for finding the volume of a cylinder is
pi x Radius squared x length
so there you go ... I just hope that you took the inside measurements.
and if you really want to nit prick, pi is just a bit more that 3.14 but we all know that don't we
eg.
ONE MILLION DIGITS OF PI
-- Edited by Cupie on Monday 11th of September 2017 10:52:55 AM
Thanks to Mr Google ... pi is commonly defined as the ratio of a circle's circumference C to its diameter d
-- Edited by Cupie on Monday 11th of September 2017 01:45:42 PM
Gday...
GEEZ you lot ... this is the only pie I am interested in ....
Cheers - John
Nearly Rocky
I guess I shouldn't be surprised at the response in this thread. It goes to the crux of the reason that many employers believe old folks to be unemployable, namely that they cannot accept that there may be a different, possibly better, way to tackle a task that they have been doing for decades.
Notice that I didn't say that my approach was better, or that any of the proposed solutions were incorrect or inferior. I merely offered an alternative method.
As for pi, I don't need to know that it is a transcendental number that has no finite representation in the decimal number system. I just need to know that pi = "pi" and let Google's calculator handle the rest.
If anyone had bothered to follow the link I provided, they would have seen the obvious utility of this tool. I also provided the sample output, verbatim, to illustrate the importance of parentheses, and the precision of the calculator.
As for computational aids, they can be useful, especially when one doesn't understand the underlying concepts and is totally dependent on rote learning. However, I prefer not to clutter my brain with things I don't need. Instead, all I need to remember is that volume equals area times length. This applies equally to a cylindrical pipe as it does to a length of timber or a stick of licorice.
So ...
The last line illustrates the reason for the "0.8" in the rule of thumb calculation.
Furthermore, I can mix up the units of length and volume in any way I like. I don't need to remember that the diameter is in millimetres and the length in metres, nor do I need to remember to apply a conversion factor of 1000. Google's calculator does all that.
pi x ((6 inches / 2) squared) x 2.2 m in litres
pi x (((6 inches) / 2) squared) x (2.2 m) = 40.1312323 litres
pi x ((6 inches / 2) squared) x 2.2 m in US gallons
pi x (((6 inches) / 2) squared) x (2.2 m) = 10.60155 US gallons
pi x ((6 inches / 2) squared) x 2.2 m in firkins
pi x (((6 inches) / 2) squared) x (2.2 m) = 0.980848151 firkins
pi x ((6 inches / 2) squared) x 2.2 m in cubic cubits
pi x (((6 inches) / 2) squared) x (2.2 m) = 0.419917362 cubic cubits
Some care needs to be taken to ensure that Google evaluates the expression in the correct order.
The following examples illustrate this point:
http://www.google.com.au/search?q=pi+x+50mm+squared+x+2.2m+in+litres
pi x (50 (mm squared)) x (2.2 m) = 0.345575192 litres
http://www.google.com.au/search?q=pi+x+(50mm)+squared+x+2.2m+in+litres
pi x ((50 mm) squared) x (2.2 m) = 17.2787596 litres
Ha ha .... Love it ...
Though my experience differs from the opening statement.
I found that the new ones on the block usually came up with a 'new way' of doing things dressed up with a confusing range of terms. We oldies were often able to provide evidence of the 'new approach' having been tried unsuccessfully in the past. Often they were out to add another page to their CV before moving on before the results of their innovations were evident.
Mind you it is over 20 years since I retired so perhaps things have changed.
Having said that, I frequently observe people doggedly following the perennial 'Calf Path'. Which perhaps supports dorian's statement.
So there you go.
Time for a cuppa before getting the van ready for a short trip up to The Carnival Of Flowers.
Now what was this thread about?
Hi
Just to provide another look at the inexact PII. In decimal form it is inexact, BUT in ratio form it is not. 22/7 is exact and I use that all the time when I do a simple calc for a circle. Easy to remember too
The ancients who found these old relationships never used decimals but mostly saw it all in ratios. Easy to understand too.
Jaahn
No, it isn't.
7 x (22/7) = 22
7 x pi = 21.9911486
By whose calculation ??
Jaahn
http://www.thefreedictionary.com/calculator
My dad always used to tell me "keep your mouth shut that way people will only THINK you're stupid"
Hi Keith (OP) ..
Don't mind Hewy54 ... or his Father.
I hope we put you right.
I was looking at making one up out of plastic pipe but space did not permit...however, after measuring, this fitted just nicely and cost about $60.00 from Ebay plus other cheap connections from Bunnings.
Hi
What to say, I am gutted. My old maths teacher told us that 22/7 was exact and now I find it is not
Out by an enormous 4 in 10000 (approximately of course). I will have to go and find his last resting place and spit on his memory. Who can you trust these days 
mea culpa, mea culpa !
Jaahn
Opinion without 3.14 is an onion.
I'll run now.
Yep...waaaay back. Found out enough from the paddock variety calculations first up to work out it aint gunna work....so will get the grey water system added as van is being built.
Cheers Keith