Using U/W Scooters for sand blowing

[Jason in Enid]

Cornelius, that's a very interesting design. It looks extremely heavy, does it have to be tethered to the boat? Also, have you found that the prop and motor tend to wear from circulating sand when the intakes are down?

 

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[cornelis 816]

Jason if you are afraid that the sand will harm the prop all you have to do is extend the blowerpipe . This is also handy when you ride the scooter in its normal use . Cornelius

 

[cornelis 816]

Some better pictures . Cornelius

 

[Jason in Enid]

Is that painted PVC or metal?

 

[stevemc]

PVC

 

[Darren in NC]

I used a powerful electromoter being connected to the inboard battery or the alternator .
If you turn the two elbows in the other direction ( the elbows can pivot ) than the outflow and the inflow will work together and the scooter can be used as a full working scooter . Cornelius

I really like this idea, Corny. I remember we were discussing this a few years ago. Glad to see you built it. Question - how can it be used as a scooter if it's tethered to the boat?

 

[Au_Dreamers]

That is awesome Cornelis !!
Between that and your ROV you are a regular MacGyver
What are the pipe dimensions if I might ask?

 

[cornelis 816]

Darren . It is only to be used near the boat . And ofcourse for blowing sand . Cornelius

 

[capt dom]

Slick contraption Cornelius!

There is one photo in your series where the reverse
thrust nozzles are turned 90 degrees that may
make the device a bit tough to hang on to...

You probably put that in there to see if any one was
really looking hard at your photos!

On another note I new a fellow who fabricated a
"bazooka" type electric" blower he placed upon
his shoulder - then ran a cord up to an onboard
generator... Providing you didn't get the electric cord
in the intake - this device could flat
move some overburden.....

Attached is the same concept but factoring out the batteries
and the electric cord and replacing it wit a two inch
high pressure water hose.

What I am doing in this photo is turning
a 6 inch Keene venturi gold dredge nozzle around
and using the thrust from the exit side of the venturi to act as a
blower.... Its easy to hold on to.... no moving
parts to grab your hoses or get your fingers stuck in
and it can flat move some overburden - fast!
check it out!

 

[cornelis 816]

Capt Dom . Here you showed that there are more ways than one to skin a cat . Your contraption is more based on air-bubble flow than on water flow though . If you look at my pictures you see two black grips . The motor is pointing toward you so there is an easy grip . Om the contrary of what you say it is very easy to handle . If you point the motor away fro you , you can use the blower as a regular scooter . If you think the outflow will be too close to the elbows all you have to do is extend the outflow pipe away from the elbows . This makes it easyer to ride the blower when used as a scooter . I am working now on a modus to use a regular engine to drive a propellor on a 90 degrees down the bottom of a pontoon boat . Here for I am using a small car differential ( to change the horizontal driven shaft into a 90 degr. driven shaft ) . By using this system you do not have to anchor your boat to keep it in place . Regards Cornelius

 

[stevemc]

Capt Doms sand blower is water flow, not air. It is a dredge with the big hose taken off, and blowing out water. Instead of sucking up sand, it blows it. During the first years of working the 1715 fleet, a small barge had a large propeller sticking straight down below in the middle. It was the first to do that, and they discovered it would blow the sand away. It was made to blow clearer water down into the lower murky layer, so typical of that area, especially during low tides. Then the ashcan (the first thing they were called, since it used metal garbage cans) was invented which were the same as todays prop blowers. And Dom, Cornilius's blower has intake on the elbows, the middle straight one is outflow. You still would need to have it anchored in place.

 

[Au_Dreamers]

Cornelius,
Harold Holden built a barge like that, if I remember correctly when he worked the 1810 South of Ft Pierce inlet. He told me it made some of the biggest holes he'd ever dug.

I can't remember exactly but I think one hitch he had to overcome was the venturi the "prop" created.

I always wanted to build something like that because of the huge amounts of overburden it can move, which is the key in finding these storm wrecks near the beach.

Hmmm I wonder if Bonnie has the info on Harold’s barge…

 

[capt dom]

Right Steve,

We are pumping high pressure water not air
and using the reverse venturi effect but the trust is manageable
like that of a 2 inch high pressure fire hose.

The six inch suction side - off sets the six inch "blower column"
Its easy to hold on to and a heck of a lot better than
using scooter thrust.... Length of high pressure supply hose
from "motive pump" is a factor but controllable.

now folks this is what this blogging site is all about
sharing quality information - without insulting
each other.

Now if that is being "pompous" I am guilty as
charged!

 

[stevemc]

What I meant to say to cornilious was, if he makes a pontoon boat with a prop sticking straight down, you will still need to use several anchors, as it will still move around if you dont. Carl Fizmer used a jetski with a PVC elbow on the jet outflow years back on a real shallow wreck (3') He drilled a hole through the outflow nozzle and another through a 90 degree PVC elbow, and a long bolt to hold it all, and it worked good. Not like a big diesel prop, but it was able to do this in very shallow water.

 

[Jason in Enid]

Dom, I'm curious about your system. Why don't you use the discharge hose? It would seem that laying 20, 30, etc feet of hose would move the sand far enough away to keep it from falling back into the hole. I've only used a gold dredge as a gold dredge, so your adaption is interesting.

 

[capt dom]

We often do use a discharge hose
but One day the hose slipped off
and I found if I turned the thing around
the pressure from the outflow column of
water was real effective for for "dusting"
and blowing away shallow sand.

I will attach a photo or two of another venturi
dredge system we have experimented with

 

[4theMoney]

I use an apollo av1 aka dacor seasprint.... It has a three pitch adjustment prop that comes in handy for digging. The batteries are good for about an hour and the scooters hold up well with repeated use.

 

[FISHEYE]

I have a 6 inch water dredge like dom's.I made it out of steel and use a 2 inch gas water pump on it with a 50 foot 2 inch fire hose.I built it 30 years ago when my dad wanted a canal dug at his lake property.I dug that canal 5 foot deep and 8 foot wide 100 foot long in 4 days with this dredge.Now his canal is all filled in so it looks like i have to dig it out again.

 

[coin_diver]

Dom is correct. I had Keene build a version of this for my specific needs. Starting w/ a 4" dredge but bigger pump and engine. Then I sent down the HP water 30' to a 4" jet tube held in place w/ a small anchor and pointing out into the river behind me. From the jet a 10' hose went to a 4" swivel nozzle. On the surface people could only see an air line and press. hose going down. No disruption or sediments. But on the bottom, this monster went through huge piles of boiler slag and kept the vis good. I simply said it was my air supply and everyone was content.

For anyone interested I have a genuine Farrallon Mk V DPV for sale.