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p3tris
09-06-2009, 03:50 AM
Hi guys, it's nice to find your community here (even if i'm from half the way around the world).

While at a friend's house i saw he had a "Homemade" sprayer. It consisted of a container (it must have been 60-80 ltrs) an electric pump and really long hose with a spray gun at the end. The Hose must have been 25-30m long. The whole installation was immobile under a shed in the garden.

I like the idea! For my garden i need approx 320 liters to cover the premises. I have a 20 liters backpack sprayer, but as you can calculate that means more than 16 refills and my back hurts in the end. My friend says he inherited the sprayer from the previous owner, so he cannot help me.

What i want is some guidelines to the sizing of the whole thing. How big the container? What kind of a pump? The diameter of the hose? what kind of spray gun? What should i look for? (pressure, length of the hose-longer=better)

I am a licensed electrical engineer (so the pump and the electrical installation won't be a problem) and i have no problem "making things".

I'm willing to take pictures if this project takes of and post them back here at the end.

Thanks!

greendoctor
09-06-2009, 04:26 AM
My first question is why do you need to apply 320 liters to cover your property? How high up do you need to spray and at what volume? Long hoses are not necessarily the best thing. A long hose causes you to lose pressure and volume at the end, especially if the hose has a small bore. If it were just my property that I had to spray, I would look at an engine drive knapsack sprayer or an engine drive sprayer on a cart. The knapsack sprayers usually hold 25 liters, operate at 25 bar pressure and discharge up to 8 liter per minute. A sprayer on a cart holds up to 100 liter and has a similar rate of discharge. I am in the business of treating lawns and trees. For most uses, an engine drive knapsack has proven to be very handy. There is no long hose to get tangled or snagged. Hoses are also very good at ripping plants out of the ground. So I do not care for them in many of the landscapes I maintain.

If you really want a stationary spray unit. What you need is a pump capable of at least 20 bar pressure, over 4 liter per minute output and hose with a 10MM bore. It is hard to say how long the hose should be. The spray gun used depends on what you are trying to treat. Dense shrubs and low growing flowers are best handled by a different gun from what is used to spray tall trees. I know I keep one gun for tall trees, one for lawns, and one for shrubs and low flowers. They are very different in operation and appearance from each other.

p3tris
09-06-2009, 07:27 AM
My first question is why do you need to apply 320 liters to cover your property? How high up do you need to spray and at what volume? Long hoses are not necessarily the best thing. A long hose causes you to lose pressure and volume at the end, especially if the hose has a small bore. If it were just my property that I had to spray, I would look at an engine drive knapsack sprayer or an engine drive sprayer on a cart. The knapsack sprayers usually hold 25 liters, operate at 25 bar pressure and discharge up to 8 liter per minute. A sprayer on a cart holds up to 100 liter and has a similar rate of discharge. I am in the business of treating lawns and trees. For most uses, an engine drive knapsack has proven to be very handy. There is no long hose to get tangled or snagged. Hoses are also very good at ripping plants out of the ground. So I do not care for them in many of the landscapes I maintain.

If you really want a stationary spray unit. What you need is a pump capable of at least 20 bar pressure, over 4 liter per minute output and hose with a 10MM bore. It is hard to say how long the hose should be. The spray gun used depends on what you are trying to treat. Dense shrubs and low growing flowers are best handled by a different gun from what is used to spray tall trees. I know I keep one gun for tall trees, one for lawns, and one for shrubs and low flowers. They are very different in operation and appearance from each other.

Hi, thanks for answering so quickly! I calculated the 320 litres. I have knapsack sprayer with 20 ltrs capacity and on average i need to refill it 15-16 times (with the appropriate mixture of course) to spray everything in the garden. I have olive trees, lemon trees, a tangerine tree, 2 vines (which i have grown into sheds. Meaning i grew them 3m tall and then used them to cover a piece of land), peach trees. Also i have many other trees that i don't know their names (in English). The trees are on average 2.5-3 meters tall (and thus cannot easily be ripped out from the ground by the hose).

The knapsack sprayer has the problem of having to refill and do the mixture 15-16 times to cover the whole garden and going forth and back for the refills! The cart has the problem that my garden is in horizontal levels, each level separated from the next with 4-5 steps. Taking a cart with an 80-100 liters tank up and down those stairs would kill me :weightlifter:

The stationary spray unit i thought would be great because my house is situated in the middle of the garden and i believe with a hose of 25-30 meters long i could spray everything.

greendoctor
09-06-2009, 07:42 AM
Seeing your situation described in detail, this is the one time a centrally located spray system makes sense. The reason why a hand operated knapsack sprayer uses so much liquid is its low pressure and consequent poor coverage. The average hand sprayer is only good for 2-3 bar and that is if you are really pumping. Way too much effort. I think a 150 liter tank, a 15-25 bar pump and 30 M of hose with a variable pattern gun would do well for you. Does it have to be electric? Electric pumps have limits on volume and pressure unless you are talking about a belt or direct drive triplex pump and a big motor to operate it. Japan has engineered some great pump engine units that could well be used stationary, even though they are designed to be portable. They also would cost less than an equivalent electric drive triplex pump. Have a look at these http://www.maruyama-us.com/uploadedFiles/Maruyama_US/Support/Specification_Sheets/NPOWERSPRAYERS-COMPACT.pdf http://www.maruyama-us.com/uploadedFiles/Maruyama_US/Support/Specification_Sheets/08POWERSPRAYERS-SETS.pdf

Ric
09-06-2009, 10:12 AM
p3tris

I will suggest the below link as a possible 12 V pump for a home made unit. I have several of these pumps on different set ups and they work fine for me.

http://www.tractorsupply.com/agriculture/agricultural-sprayers-spraying/sprayer-pumps/12-volt-pumps/12-volt-electric-diaphragm-pump-with-demand-switch-and-harness-2111954

I power these pumps from both my truck battery and a Small rechargeable Gel Battery to make them portable. I have 2 different sets ups that push a 300 ft hose (100 Meters approx) from 25 gallon tanks (100 Liters Approx). For portability I also have a 2 wheeled Golf Bag cart that I converted with a Gel Battery and a 5 Gallon (20 Liter Approx) Jug as a tank. I use one of those 20 ft (6 meter approx) Curly Que hoses that stretches on the Golf Bag cart.

Remember just like electric wire, Hose has resistances. The longer the hose the more resistances and the lower the PSI and GPM.

Falcon50EX
09-06-2009, 11:02 AM
p3tris

I will suggest the below link as a possible 12 V pump for a home made unit. I have several of these pumps on different set ups and they work fine for me.

http://www.tractorsupply.com/agriculture/agricultural-sprayers-spraying/sprayer-pumps/12-volt-pumps/12-volt-electric-diaphragm-pump-with-demand-switch-and-harness-2111954

I power these pumps from both my truck battery and a Small rechargeable Gel Battery to make them portable. I have 2 different sets ups that push a 300 ft hose (100 Meters approx) from 25 gallon tanks (100 Liters Approx). For portability I also have a 2 wheeled Golf Bag cart that I converted with a Gel Battery and a 5 Gallon (20 Liter Approx) Jug as a tank. I use one of those 20 ft (6 meter approx) Curly Que hoses that stretches on the Golf Bag cart.

Remember just like electric wire, Hose has resistances. The longer the hose the more resistances and the lower the PSI and GPM.

Ric, would you post some pictures of you setups. I have a 20gal tank that I would like to put on a dolly and pull around.

Thanks for any info:usflag:

Falcon50EX
09-06-2009, 11:12 AM
Seeing your situation described in detail, this is the one time a centrally located spray system makes sense. The reason why a hand operated knapsack sprayer uses so much liquid is its low pressure and consequent poor coverage. The average hand sprayer is only good for 2-3 bar and that is if you are really pumping. Way too much effort. I think a 150 liter tank, a 15-25 bar pump and 30 M of hose with a variable pattern gun would do well for you. Does it have to be electric? Electric pumps have limits on volume and pressure unless you are talking about a belt or direct drive triplex pump and a big motor to operate it. Japan has engineered some great pump engine units that could well be used stationary, even though they are designed to be portable. They also would cost less than an equivalent electric drive triplex pump. Have a look at these http://www.maruyama-us.com/uploadedFiles/Maruyama_US/Support/Specification_Sheets/NPOWERSPRAYERS-COMPACT.pdf http://www.maruyama-us.com/uploadedFiles/Maruyama_US/Support/Specification_Sheets/08POWERSPRAYERS-SETS.pdf

Have not seen that pump setup how much? Most backpacks are around 500$ you can build one for half that.

Ric
09-06-2009, 11:34 AM
Ric, would you post some pictures of you setups. I have a 20gal tank that I would like to put on a dolly and pull around.

Thanks for any info:usflag:

Falcon

Sorry no Camera. I keep my Pull around unit to 5 gal and under because of weight. Even at 5 Gallon in thick thatch it can be a Pain. Any thing Bigger should be pulled by a Tractor of some kind IMHO. I use Blue Gas jugs and can change them out To shoot different products or Cocktails of Herbicides. I use this unit mostly for spot treatment but it works well for blanket treatments as well.

BTW I pick up Golf Bag dollies from Garage sales for $ 2.00. Actually my neighbor does it for me since I don't garage sale shop. I got the Idea from the same neighbor who uses a 3 gallon pump up sprayer on his around the house. Here in God's Waiting Room we try and work smart not hard.

Falcon50EX
09-06-2009, 11:43 AM
Falcon

Sorry no Camera. I keep my Pull around unit to 5 gal and under because of weight. Even at 5 Gallon in thick thatch it can be a Pain. Any thing Bigger should be pulled by a Tractor of some kind IMHO. I use Blue Gas jugs and can change them out To shoot different products or Cocktails of Herbicides. I use this unit mostly for spot treatment but it works well for blanket treatments as well.

BTW I pick up Golf Bag dollies from Garage sales for $ 2.00. Actually my neighbor does it for me since I don't garage sale shop. I got the Idea from the same neighbor who uses a 3 gallon pump up sprayer on his around the house. Here in God's Waiting Room we try and work smart not hard.

Ric, I have read a lot of your post and very good info Thanks from a new guy on the block. It is my first year in business I still need to find reasonable cost insurance for my little operation.

Thanks

p3tris
09-06-2009, 01:30 PM
Hey Ric, thanks for the reply.

Will this setup have enough juice to spray a 2,5-3m tree through a 30m long hose? Because the best electric (12V) pump i found tops at 90 PSI (~6.2 bar). If you can post some more details of your setup (what kind of hose? 3/8''?) a picture maybe?

Also what does "with Demand Switch and Harness" means? Is it vital? :P

(because i live outside US and sometimes is hard to find what i want...)

thanks!

p3tris
09-06-2009, 01:46 PM
Let's say, would this one make the job? http://cgi.ebay.co.uk/Propump-12v-120psi-diaphragm-pump-New_W0QQitemZ130324803681QQcmdZViewItemQQptZUK_HomeGarden_CLV_Cleaning_CA?hash=item1e57f6b061&_trksid=p3286.c0.m14

it's at 120psi = 8,3 bar, BUT 4 lpm = 1,06 gpm ~which is little?

greendoctor
09-06-2009, 04:18 PM
That is about half the output of what I suggest. If you are trying to spray trees and tall plants, twice that output is better. The gas engine pump units are expensive, but again probably less than a CAT pump coupled to an electric motor.

greendoctor
09-06-2009, 04:25 PM
Have not seen that pump setup how much? Most backpacks are around 500$ you can build one for half that.

The small MS 072 EH is about $800. It comes with about 50 ft of hose, spray gun and intake and bypass pipes. I do not know of any electric pumps that can match the output for the same price. I know small fruit and vegetable farmers that use this to spray their crops. The belt drive pumps are over $1000. However, add a tank and hose reel for something that is better than or equal to a Lesco sprayer.

p3tris
09-06-2009, 08:12 PM
I'll hit the market tomorrow to get a look at what is available here. I'll gather some specs and prices and i'll come back here for some more info!
You guys are really great!

Ric
09-06-2009, 08:13 PM
Hey Ric, thanks for the reply.

Will this setup have enough juice to spray a 2,5-3m tree through a 30m long hose? Because the best electric (12V) pump i found tops at 90 PSI (~6.2 bar). If you can post some more details of your setup (what kind of hose? 3/8''?) a picture maybe?

Also what does "with Demand Switch and Harness" means? Is it vital? :P

(because i live outside US and sometimes is hard to find what i want...)

thanks!

p3tris

You will have to forgive today because I am just taking a break from some heavy Labor Day partying. We been to the Beach and now I have a Clothes Change break before going to the House party.

3 Meters = 9.75 feet in my book and While I am only 5'5" (170 CM) tall I can reach close to that Height. Add a short spray wand and you are there.

30 Meter hose is 100 feet and friction loss is not going to be real great. I don't have the time right now to look up the formula which is for solid pipe and not hose, But from my days of designing irrigation systems 100 ft is no great Friction loss. Friction loss in hose is going to be slightly higher because of bends etc of hose. One of my units actually has 180 feet of 1/4 air hose and 100 feet of 1/4 Airless paint hose for a total of 280 ft. It works fine for blanket spraying Herbicides on turf. BTW Left over Junk I made use of. BTW all propose Agi hose is rated at 600 PSI and works great. This is normally Yellow in color and holds up for a long time.

The old saying is "You don't always get what you pay for" But Remember "You never get more than you pay for" These Pumps are Cheap and while you can get rebuild kits for them, They cost almost as much as a new pump. However I have had them last for many years. At best They put out what they claim. But they are not intended as high volume, high pressure. It may take you a little longer to spray than 10 GPM pump rated to do 600 PSI.

Pressure Switch: Most can be adjusted to gain more PSI than recommended. Generally there is either a Screw or Allen head that you tighten just under the top switch cover. As for by passing them, I have had them go bad and by passed them until I could buy a new pump. The trick is to not let them build too much presser. Either keep spraying or turn to pump off. You have about a 2 minute window to let the pressure build before turning it off or releasing pressure.

BTW If you Go to Northerntool.com they have a 220 psi model but you give up chemical resistances and lower price. Sorry I don't remember PSI to Bar conversion and I am too lazy to look it up. Oops Party time GTG.

p3tris
09-07-2009, 06:21 PM
greendoctor i agree with you that the setup you suggest is perfect. But i don't have the money (~800 bucks) to invest on this project. It's too much for my garden. I would invest it if i had an income from it, but the fruit-oil etc i get from my garden don't add.

If you could explain to me (since i'm a novice to this) what the GPM affects and what the pressure!
I found an electric pumps:
1) 8.3Bar + 1.05 gpm (~$110)
2) 6.9Bar + 1.2 gpm (~$110)
3) 2.8Bar + 4.5 gpm (~$120)

ksJoe
09-07-2009, 07:21 PM
Since your looking for low budget, have you considered the very low end?

http://www.amazon.com/Gilmour-362-Professional-Pre-Mix-Sprayer/dp/B00002N67I

It connects to a garden has and mixes as it sprays. The black plastic tip is a deflector to fan out the spray when spraying large low areas. If you take it off, it will shoot up to around 30 feet (depending on water pressure).

I got one of these recently and have been pleased with it. Initially I did some testing with water in the bottle, to see how much I applied per 1000 square feet. Then when I switched to pesticide, which was thicker, it didn't apply near as much. So I've had to experiment a bit to get the right amount applied. But overall, I'm pleased with it. I got mine locally with a coupon for 8 USD.

greendoctor
09-07-2009, 07:32 PM
greendoctor i agree with you that the setup you suggest is perfect. But i don't have the money (~800 bucks) to invest on this project. It's too much for my garden. I would invest it if i had an income from it, but the fruit-oil etc i get from my garden don't add.

If you could explain to me (since i'm a novice to this) what the GPM affects and what the pressure!
I found an electric pumps:
1) 8.3Bar + 1.05 gpm (~$110)
2) 6.9Bar + 1.2 gpm (~$110)
3) 2.8Bar + 4.5 gpm (~$120)

The 8.3 bar/4 l pump is close to the output of the gas engine. Low pressure is horrible for treating trees and shrubs. If those are small plunger or diaphragm pumps, they run on 12VDC power. A deep cycle battery will power them.

p3tris
09-08-2009, 03:26 AM
they are diaphragm pumps. They are 12VDC but i also found one at 4.2 bar powered from 230VAC. I asked for the flow rate though since it wasn't in the listing.

ksJoe, i tried 2 of those things and was disappointed! The mixing ratio was not always the same and if you use strong pesticides then...

Ric
09-08-2009, 01:15 PM
Greendoctor

While I agree higher pressure is needed for trees and shrubs when spraying commercial. A low pressure long wand can be inserted past the canopy and turned to spray the under side of leafs. Sure this takes longer, but in this case the application is not for commercial proposes. The economics of the green industry are such that contact pesticides are less expensive in most cases. Citrus groves in my area use very large mist blowers to insure full coverage of contact pesticides. I find the more expensive systemics are a better value in my operation and my available equipment for my size operation. I find mist blowers are either small back pack type units or large tow behind units neither of which works for me.

While I love my SRS 600 electric back pack sprayer for spot treatment. It does not have the out put to keep up on blanket treatments. I knocked Airheads homemade Back Pack sprayer but now see a value in it, because of a high gpm which will keep up on blanket sprays. My Golf Bag Dolly sprayer is basically a Rip Off of Airhead's Idea only on wheels. And it folds up nicely for transport.

p3tris

GPM and PSI are directly related in the fact each model pump only puts out so much energy. Final tip size plays the biggest issue. A large tip allows a lot of liquid but at a lower pressure. A Small tip allows a smaller volume but because it is restricted, at a higher pressure. They type of application you want make should determine your selection of equipment. In commercial work, time is a factor. For hobby work, time is not as important and large jobs can be done with smaller equipment.

Now as king of homemade junk, Sometimes it is cheaper to buy manufactured equipment.

p3tris
09-08-2009, 03:21 PM
Now you got really confused...

If i have higher flow means i'll get more spraying done in the same time?
Higher pressure means what? That the liquid will be shot more far away? It will shoot through the leaves? What tip i have to get? For spraying trees i mean!

If someone can explain me these with an example or so i'ld be more than grateful...

cecropia11
05-03-2013, 08:24 AM
Would a 3.2l/min(1.0gpm) 90 PSI Diaphragm Pump be enough for making a 4 GAL electric backpack sprayer.