Mouse, what's that?

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O

Open Neutral

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I'm seeking the formal name for conduit mice. The ones I am thinking of carry a payload of a cylinder of dental floss sized line, as well as a nose to snugly fit in the duct. You blow/suck it through [or both together]; it pays out line as it goes.

That way, the drag does NOT increase as it goes down the duct...until it stalls. {That of course, has NEVER happened to me...but I read about it..}

When it pops out, you pull a bigger twine with it, and then Mule Tape? or similar.

I last bought such years ago when I was getting my hands dirty daily, vice polluting my mind doing paperwork.

But both on-line and on the phone, suppliers know only about the cylindrical nose, with a eye to pull string through.

Does anyone know names/ mfgr's/ model #'s of what I seek?
 
Little Bill

Little Bill

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Open Neutral said:
I'm seeking the formal name for conduit mice. The ones I am thinking of carry a payload of a cylinder of dental floss sized line, as well as a nose to snugly fit in the duct. You blow/suck it through [or both together]; it pays out line as it goes.

That way, the drag does NOT increase as it goes down the duct...until it stalls. {That of course, has NEVER happened to me...but I read about it..}

When it pops out, you pull a bigger twine with it, and then Mule Tape™ or similar.


I last bought such years ago when I was getting my hands dirty daily, vice polluting my mind doing paperwork.

But both on-line and on the phone, suppliers know only about the cylindrical nose, with a eye to pull string through.

Does anyone know names/ mfgr's/ model #'s of what I seek?
Click to expand...



I found them on Ebay in several sizes, they are from Greenlee. If you don't find them, PM me and I'll send you the link as I don't think I'm allowed to post it here.
I've also heard of people using a plastic grocery bag and kite string and somehow plastic bag tied on or around a small balloon with string.
 
R

realolman

Senior Member
I used to make my own from a hunk of foam rubber about 2" thick... cut out disks by pounding a piece of conduit thru the foam on a hunk of wood.... also cut out some slightly smaller discs from thin plastic or cardboard and punch two small holes in them so they resemble a button. you could probably use buttons if you had some.

fold over a piece of thin wire like motor or coil winding wire and thread it thru a button, then a piece of foam, then another button sandwitching the foam between two buttons.

hook two of these sandwitches together in "series" in a way that will allow the whole contraption to hinge, so it will sail right around a bend ....lastly form a loop in the wire in the last one to tie a string.

smear a little lube on the whole shebang and it'll pull mason cord right thru a pipe with a vacuum slicker'n owl poop on a doorknob. Might pull you through if you aint careful.
 
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O

Open Neutral

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Line package

Line package

Thank you; that's what I remember. Never would have guessed "line package..."

But I need one for 2" and for longer than any length I see.
Guess we better install the string before it gets too many lengths long.

Maybe we'll try dragging a mason's twine string along...We will have high pressure air available.
 
kwired

kwired

Electron manager
Location
NE Nebraska
Open Neutral said:
Thank you; that's what I remember. Never would have guessed "line package..."

But I need one for 2" and for longer than any length I see.
Guess we better install the string before it gets too many lengths long.

Maybe we'll try dragging a mason's twine string along...We will have high pressure air available.
Click to expand...

volume capabilities of the air supply is more important than the pressure. The larger the raceway the more important volume becomes.
 
mivey

mivey

Senior Member
Open Neutral said:
Thank you; that's what I remember. Never would have guessed "line package..."

But I need one for 2" and for longer than any length I see.
Guess we better install the string before it gets too many lengths long.

Maybe we'll try dragging a mason's twine string along...We will have high pressure air available.
Click to expand...
Why not just use the separate carrier and the tag-a-long line package? They have lengths up to 1200 ft. The Greenlee fish line doesn't travel with the carrier but is 2750 ft long for the small roll and 6500 ft long for the bucket. I don't think you are going to be more than that between your pull points.

These are probably better than mason twine because they are center fed and release much easier.
 
O

Open Neutral

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The basic issue it do you pull the line, or lay it out as you go? Laying out means the drag does not increase with distance. The tag-a-long LP2207T is 800 ft long but appear to be $10 each. (Must have lots of gold in it...)

The other issue with pulling is the line must slip by the seal on the blower end.

A high pressure stored air source, such as a K-bottle or SCUBA tank, expands to be a large volume of low pressure air.
 
kwired

kwired

Electron manager
Location
NE Nebraska
Open Neutral said:
A high pressure stored air source, such as a K-bottle or SCUBA tank, expands to be a large volume of low pressure air.
Click to expand...

True but many have the misconception that an air compressor will move a piston through a raceway faster than a high volume blower because there is higher pressure involved. The more volume of air that can be put into the raceway in a short time, the faster it will push the piston that does not require much pressure to move. Compressed air flowing through a small orfice or small tubing does not necessarily provide a high volume of flow.

If you were to use a piston that provided a good seal against the sides of the raceway you should be able to displace it all the way to the other end of the raceway if the raceway is sealed well enough by using a hand pump designed for filling sports balls or bicycle tires. Will take a little time to run through a couple hundred feet of 4 inch conduit as there is a lot of air that needs displaced.
 
S

shepelec

Senior Member
Location
Palmer, MA
A good wet/dry vac and a plastic bag has always worked for me.

Anytime I used a "mouse" it always got stuck, unless it was with a "jet line" tank. A thousand psi of CO2 and them suckers really took off.
 
O

Open Neutral

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Inside the Beltway
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Engineer
I had a stuck mouse once, and no high [volume/pressure] gas source, so I used....water. With less than optimal sealing, the denser H2O did the trick, and it was readily available in quantity.

It did the trick PDQ. Then we used the shop vac to suck out the water from the low end, and pulled a rag ahead of the cable.
 
kwired

kwired

Electron manager
Location
NE Nebraska
Open Neutral said:
I had a stuck mouse once, and no high [volume/pressure] gas source, so I used....water. With less than optimal sealing, the denser H2O did the trick, and it was readily available in quantity.

It did the trick PDQ. Then we used the shop vac to suck out the water from the low end, and pulled a rag ahead of the cable.
Click to expand...

May not want to do this if your run is above a finished ceiling and you used set screw fittings:)
 
C

Cow

Senior Member
Location
Eastern Oregon
Occupation
Electrician
How far are you going?

We do some long runs with nothing more than a shop vac. Just a couple I can think of in the past:

1300' 2" pvc with a plastic bag and 210 lb pull string

1600' 2" pvc with a plastic bag and greenlee kite string

Anything shorter than this should be gravy. The important part is getting the string in as soon as possible after the conduit is installed, then you can usually avoid dealing with water getting into the conduit over time.
 
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