Leaf blower

Status
Not open for further replies.
You might do it with a leaf blower, but forcing that much water out might take a big air compressor. Either way, try just getting air to move before putting your rat and string in.
 
I use leaf blower all the time, with a plastic shopping bag tied to the fish string works like a champ. I think you will need to find some other method to remove the water from that large of a raceway especially with the length you have there. It recently had a 1-1/4 run of only about 100 feet and it took some time as well as making sure there were no leaks in the blower supply to get the water out of that run.
 
mcelweec@gmail.com said:
Has anyone tried a leaf blower for conduit fishing,I need to fish a 4" RGC water logged conduit around 600'.
Click to expand...
By my calculations (someone check me) that's about 3250 lbs of water if the conduit is full and if its ID is 4". A leaf blower isn't gonna do it.
 
ggunn said:
By my calculations (someone check me) that's about 3250 lbs of water if the conduit is full and if its ID is 4". A leaf blower isn't gonna do it.
Click to expand...

The volume of water is not important. What counts is the pressure head, which in turn depends on the difference in height between the lowest point in the water filled section and the level at which the water will pour out the other end of the conduit. A wet vac can suck several feet of water, while a leaf blower probably does not generate more than a few inches of pressure.
 
GoldDigger said:
The volume of water is not important. What counts is the pressure head, which in turn depends on the difference in height between the lowest point in the water filled section and the level at which the water will pour out the other end of the conduit. A wet vac can suck several feet of water, while a leaf blower probably does not generate more than a few inches of pressure.
Click to expand...
I submit that the volume of water is important. In order to blow the water out of the conduit you have to get the whole volume of water moving. If the conduit were only 6" long the leaf blower would have no problem clearing it.
 
ggunn said:
I submit that the volume of water is important. In order to blow the water out of the conduit you have to get the whole volume of water moving. If the conduit were only 6" long the leaf blower would have no problem clearing it.
Click to expand...

F=ma, v=at, --> v=t(F/M). If you have enough force to lift the water against static pressure, then it does not matter how much water you have to move, you just need to wait long enough for it to get moving. But if the 600' run of conduit has a two foot dip in the middle, it will not matter whether the dip is 4 feet long or 400 feet long. It will not move unless the pressure is high enough.
If there is more than one dip, say N, with air in between, then the pressure needed is N times the pressure needed for just one dip. And that will cause a real practical problem.

If the only problem is that the inside of the conduit is wet but not filled with water and the parachute may get waterlogged and stick to it, then the length will not matter either.
 
Last edited:
GoldDigger said:
F=ma, v=at, --> v=t(F/M). If you have enough force to lift the water against static pressure, then it does not matter how much water you have to move, you just need to wait long enough for it to get moving.
Click to expand...
Be that as it may, I think with a ton and a half of water to move (even disregarding viscosity and friction with the walls of the conduit) with a leaf blower you'd have a long wait. ;^)
 
ggunn said:
Be that as it may, I think with a ton and a half of water to move (even disregarding viscosity and friction with the walls of the conduit) with a leaf blower you'd have a long wait. ;^)
Click to expand...
While I do not. And once it gets moving, it will take just as long to get all the water out independent of what you are pushing it with. I do agree that it will take a shorter time to see water beginning to come out with higher pressure.
By your reasoning hydraulic lifts and other applications of hydrostatics would not work either.

Note: I suspect that for the OP it will not work, but because of the conduit geometry and head pressure, not because of the volume of water involved.
 
I agree you will need more pressure than a leaf blower will give you. go rent one of those big air compressors used in road construction. you will likely need to screw on some kind of fitting to the conduit.

it may take quite some time and you might not want to try and hold it in place by hand.
 
petersonra said:
I agree you will need more pressure than a leaf blower will give you. go rent one of those big air compressors used in road construction. you will likely need to screw on some kind of fitting to the conduit.
Click to expand...

You can get expansion plugs to fit inside the pipe that have a tire fill valve in them. They are used by plumbers for pressure testing plumbing systems.
(Assuming of course that there are no wires in the way.)
 
I think it helps to have an apprentice/helper at the other end of the pipe with his ear down to the pipe.
That way he can hear the water as it starts moving from blowing at the other end!:angel::D
 
GoldDigger said:
By your reasoning hydraulic lifts and other applications of hydrostatics would not work either.
Click to expand...
IMO what you are not considering is the inertia you have to overcome to get over 3000 lbs of water moving. Have you ever tried to blow the water out of a garden hose by mouth? The longer the hose, the harder it is.

C'mon, let's set up an experiment. I'll bring the leaf blower. You bring the 600' of 4" conduit. We can use my hose. :D

.
 
Last edited:
ggunn said:
IMO what you are not considering is the inertia you have to overcome to get over 3000 lbs of water moving. Have you ever tried to blow the water out of a garden hose by mouth? The longer the hose, the harder it is.

C'mon, let's set up an experiment. I'll bring the leaf blower. You bring the 600' of 4" conduit. We can use my hose. :D

.
Click to expand...

Can I come watch?:)
 
to save money you could just hook up a bicycle pump to the conduit and let your apprentice have at it.

a character building exercise.

that is what I told the guy in our shop who was working on one of my projects once when he was assigned the task of applying double sided adhesive tape to an RC module and attaching it to the back side of a contactor. I don't think he minded the first few hundred. it was the next 9000 of them that were a little tough on him. they kept bringing skid loads of contactors over to his work bench.

summer help.
 
ggunn said:
Have you ever tried to blow the water out of a garden hose by mouth? The longer the hose, the harder it is.
Click to expand...
Actually, yes, I have done the experiment. If the hose is dead level except for a bit at the far end and totally full of water, I do not have to blow harder, I just have to wait patiently for a longer time for the water to start moving.
If the hose is on uneven ground, with ups and downs and air pockets along the way, then more pressure is needed. And we can discuss the physics behind that offline to avoid boring this Forum. :)

One illustration of this is that a water level can work regardless of how long the hose is. But the longer the hose, the slower the oscillations that happen whenever you move just one end. It is all a matter of time. If you are impatient, you can blow harder instead.
 
Status
Not open for further replies.
Top