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OllieOhNine

I hate ratios...need help

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Ok, so I talked to bob at ptek and he told me to see how much chem. my injector pulled in one minute and divide that into my GPM of my machine to get my draw ratio. Well.. did that but still need some help. Here is what I have:

2.3 GPM machine

After 1 minute, injector pulled .5 gallons and just under 3 gallons came out of the nozzle. What does that tell me?

I need to know because I am trying to apply a chemical at 10% dilution and dont know how to figure out how to pre mix it so when it does come out the nozzle it is at 10% solution and 90% water (1:9 if i am not mistaken?). Thanks!

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Well by those numbers you have a 1:6 ratio, i can't really tell you much since I don't know your setup, but with my xjet I'd just put in the closest proportioner in it (i believe its 1:10, im not sure if there is a 1:9)

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It a 2.3gpm but apparently when not under pressure ya pump abit more.

If your pumping close to or want to call it 2.5gpm then could look at figures as such:

2.5/.5= 1:5 (is 20:100, 20/100, .20, 20% injection) edit: sorry, should say it is 4:1 or 4 to 1 downstreaming. The translation to percentage is partially correct in that it comes from the chem being 1/5th of the tot 2.5 gal pumped...but then of course you did imply you maybe closer to doing 3 gal so it probably off regardless..:lgbonk:

If you first cut or preproportion your chem in half before injection then your injector will make it 10%.

By calculator I just use the decimal forms of whatever I am starting with and wanting to end at.

This case it would be .20/.10=2 (is 1:2, 50:100, 50/100, .5, 50% predilution)

ps- I always get these things wrong so don't quote me.. :)

Can also use formula worked out for cutting found here: http://www.thegrimescene.com/forums/residential-pressure-washing/10204-12-5-sh-quesiton.html#post100185

Formula being C x (t/b)

C=desired cut percentage, t= tank volume, b= starting bleach, etc. percentage

example- .10 * (1gal/.20)

..or on paper can be written as:

.10 X 1 = .10 = .10/.20= .5gal chem in a 1 gal container

1----.20--.20

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Ok, so I talked to bob at ptek and he told me to see how much chem. my injector pulled in one minute and divide that into my GPM of my machine to get my draw ratio. Well.. did that but still need some help. Here is what I have:

2.3 GPM machine

After 1 minute, injector pulled .5 gallons and just under 3 gallons came out of the nozzle. What does that tell me?

I need to know because I am trying to apply a chemical at 10% dilution and dont know how to figure out how to pre mix it so when it does come out the nozzle it is at 10% solution and 90% water (1:9 if i am not mistaken?). Thanks!

Someone correct me if i'm wrong. Your downstream injector is mixing at somewhere between 5:1 and 6:1, you want 9:1. If you premix your chemicals, one part chemical and one part water, that should put you close to 11:1 or 12:1. It seems to me you should premix two parts soap to one water to put you pretty close to 9:1.

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still not helpin too much, maybe im just stupid. I get the feeling that you need to weigh the water and the chemical proportions to figure this out, I remember doing this in chemistry but not really obviously. Basically i need to know this because I want to apply a 'sealer' to vinyl siding that can improve the color/luster of siding and it works best around 10%

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Matt,

Oh Holy Hell!!.. I always screw up something or other in the numbers by way of writing the ratios wrong...please forgive.

My 1:5 is incorrect and supposed to be refuring to 4:1 (20%) downstreaming. 2.5gal= 5 tot parts when the one part of chem is .5 gal

..see the following thread where Eric and I went through this before: http://www.thegrimescene.com/forums/residential-pressure-washing/6857-sil-o-wet-plexmaster.html

Also, perhaps the "/" I use to show division one moment and then to show a fraction the next is confusing. Is why I tried to write the fractions out.

Whether yer using a downstreamer, xjet, or predilution by hand doesn't matter...they all are a way to cut or dilute.

The formula does work if you put figures down correct...

Good luck guy!...

ps--please correct if wrong..lol

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