The double-banger. Credit to Moti for the inspiration, and lack of wind for the mojo!

Hows it go?

fn genius

That's awesome!!!! I'm making one tomorrow!

That is unreal.

Does it work? you still can only get so much through the hose and nozzle. particularily if its a small old school bladder attachement.

Ha ha another example of what can be achieved with a hacksaw, duct tape and cable ties!

On a practical note, how does it go at the 'higher' pressures?
Force = pressure X area. You have doubled the area, so expect to exert double the force for the same pressure. Maybe use a gauge to check until you have re-calibrated your 'feel' at the pressure you want.

I like it though

So ezza does it improve the pump time mate? If so I'm making one on the weekend to. Surely the limiting factor is the same tube width...or maybe not, suppose the psi of the air will the greater? Not sure anyone know about area, volume of air and psi?

Hey guys,

It goes great. We used a three way Gardena splitter inside the hose at the junction (about $2) and cable ties over the top. Pretty tight, no leakage. We hacksawed off the handle of one pump and Dremelled it down so it fit like a spine into the other handle. Then drilled and screwed the two together. Finished off with a roll of gaffa.

It pumps at greater pressure now through the normal nozzle (scientific test: direct at face) than one pump. It pumped a seven metre kite up in somewhat less pumps than before (forgot to test how many it took with pre-modification pump, though my hazy memories of the last time I pumped up the 7 as that it took about twice as long!). A physics brain could probably explain the effect of twice as much air pumped through a similar sized nozzle, but its beyond me.

I'm pretty pleased with the result, now if only the farking wind would blow while I'm on Uni holidays my life would be complete :)

@skid - my tried and tested method is to pump til the kite feels hard. Flick it and it goes ping. Never fails.

Ta ezza. Damn think I have thrown out my old pumps, not gonna cut into my brand new ozone pumps. Gonna find me some oldies and try this.

Force=Pressure x Area(of pistons)

Only might be a problem if you want to pump the kite up to 9psi.
Twice as much pressure needed to push/pull the handle, getting the last few psi you will really need to apply a lot of effort.

Really like the idea tho. Will pump up super quick, especially with a hi-flo inflate valve on the kite and minimal restrictions on the hose

I'm going to try it with 4 pumps connected together. My kites seem to take ages to pump up. Over a 100 pumps for the 10m rebel. Sucks!

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Dave Whettingsteel said..

I'm going to try it with 4 pumps connected together. My kites seem to take ages to pump up. Over a 100 pumps for the 10m rebel. Sucks!

Never! 100 pumps, your short-stroking I know it!

This double pump is a good idea.
Some betterment:
1. Have the handles such that you can use one at a time or two at a time,
2. Install one-way valve on one branch pipe, pressure gauge on other branch pipe,
3. Once you reach a reasonable pressure only use one pump (one with gauge on it) to get to required pressure. One-way valve prevents air going into and out of second pump.

Wicked start to a good idea.

Great to see a bit of creativity. Goodonya. Like LostDog said, doubled up to get the volume in quick, then separated to get the pressure up might be a worthwhile mod.

Nice :)

I would run a bridge (metal ) across the two pump handles to stop any twisting or movement in the gaffa.

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LostDog said..

This double pump is a good idea.
Some betterment:
1. Have the handles such that you can use one at a time or two at a time,
2. Install one-way valve on one branch pipe, pressure gauge on other branch pipe,
3. Once you reach a reasonable pressure only use one pump (one with gauge on it) to get to required pressure. One-way valve prevents air going into and out of second pump.

Wicked start to a good idea.

Yeah, i'm with you.

One handle could bridge across both pumps , then when u need a high PSI, you could use one pump (while other handle stays low down)

I wanna pump your pump, nice work

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LostDog said..

This double pump is a good idea.
Some betterment:
1. Have the handles such that you can use one at a time or two at a time,
2. Install one-way valve on one branch pipe, pressure gauge on other branch pipe,
3. Once you reach a reasonable pressure only use one pump (one with gauge on it) to get to required pressure. One-way valve prevents air going into and out of second pump.

Wicked start to a good idea.

Alternatively you could leave the handles connected and have a 'vent' valve that can be opened/closed on the outlet of one pump (before the one-way valve).
It wont be as energy efficient as the vented pump would still go up and down, but it might be a bit simpler to construct.

Having said that, ezza's double pump is dead simple and by all reports works well. Can't argue with a simple solution that works.

Personally, I'd like to see manufacturers make the pumps with a longer stroke so each stroke pumps a bit more air than the current pumps.

Use it as a dive Hooker In the off season 2 divers 20 metres i reckon


Lol you know sometimes you look at something so simple and wonder why the Professional engineers haven't designed it before. !good work Thinking outside the Box! !

Pu

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LostDog said..

Dave Whettingsteel said..

I'm going to try it with 4 pumps connected together. My kites seem to take ages to pump up. Over a 100 pumps for the 10m rebel. Sucks!

Never! 100 pumps, your short-stroking I know it!

Pumped up rebel 10 this arvo and it took 170 pumps, do I have a problem? No obvious leaks .... Appreciate some tips!

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EastCC said..

Hows it go?

Genius now will take me half the time to pump that monster of a kite...lol

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Dave Whettingsteel said...
Pu

LostDog said..

Dave Whettingsteel said..

I'm going to try it with 4 pumps connected together. My kites seem to take ages to pump up. Over a 100 pumps for the 10m rebel. Sucks!

Never! 100 pumps, your short-stroking I know it!

Pumped up rebel 10 this arvo and it took 170 pumps, do I have a problem? No obvious leaks .... Appreciate some tips!

170 pumps? Yes you have a problem. I dont know what it is but id suggest trying another pump for starters.

Select to expand quote

ezza said..

Hey guys,

It goes great. We used a three way Gardena splitter inside the hose at the junction (about $2) and cable ties over the top. Pretty tight, no leakage. We hacksawed off the handle of one pump and Dremelled it down so it fit like a spine into the other handle. Then drilled and screwed the two together. Finished off with a roll of gaffa.

It pumps at greater pressure now through the normal nozzle (scientific test: direct at face) than one pump. It pumped a seven metre kite up in somewhat less pumps than before (forgot to test how many it took with pre-modification pump, though my hazy memories of the last time I pumped up the 7 as that it took about twice as long!). A physics brain could probably explain the effect of twice as much air pumped through a similar sized nozzle, but its beyond me.

I'm pretty pleased with the result, now if only the farking wind would blow while I'm on Uni holidays my life would be complete :)

@skid - my tried and tested method is to pump til the kite feels hard. Flick it and it goes ping. Never fails.

Hey Ezza,

believe it or not, last week, totally separate from you and due to a serious lack of wind during my holidays, i built a set-up with a T-junction garden fitting i found in my shed and black duct tape and some zip ties. I also tested it on my 7m. Definitely less pump time, though due to a few leaks in the joiner and the amount of force from the double pump, i had to resort to a single pump to easily get the kite to a ping pressure.

Here is a pic . . . not as neat as your set-up but this was just to see if it would work out.

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max_ob said...



Hey Ezza,

believe it or not, last week, totally separate from you and due to a serious lack of wind during my holidays, i built a set-up with a T-junction garden fitting i found in my shed and black duct tape and some zip ties. I also tested it on my 7m. Definitely less pump time, though due to a few leaks in the joiner and the amount of force from the double pump, i had to resort to a single pump to easily get the kite to a ping pressure.

Here is a pic . . . not as neat as your set-up but this was just to see if it would work out.

As Ezza's self appointed legal representitive i regret to inform you that you have crossed the line on several patent pendings therefore you must cease all unauthorised experimental testing of "The superpump" and dutifully destroy any prototypes and blueprints of said patent pending .

I've represented Ezza in "how did that happen, I've kited cloudbreak all week " incident, and the case of the "who am i " mystery for which Ezza you are in arrears in payment of one largie, it's ok i'll add it to the bill

I trust you will adhere to the terms above max until the anti -patent squad raids your premises
Yours Sincerely
The Burglar

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beefarmer said...

Dave Whettingsteel said...
Pu

LostDog said..

Dave Whettingsteel said..

I'm going to try it with 4 pumps connected together. My kites seem to take ages to pump up. Over a 100 pumps for the 10m rebel. Sucks!

Never! 100 pumps, your short-stroking I know it!

Pumped up rebel 10 this arvo and it took 170 pumps, do I have a problem? No obvious leaks .... Appreciate some tips!

170 pumps? Yes you have a problem. I dont know what it is but id suggest trying another pump for starters.

Dave your pump is losing its seal mate. I remember my 11m rebel used to take 110 pumps. I used to count them on an ozone pump. My 17m zephyr takes 50 to have shape and 20 more for 8psi. High volume flow is a must for all kites I reckon.

GREAT IDEA!!!
One comment though - coming from the no. of stuffed pumps I see in the shop.
The double pumps lite might be way longer if the handles are not locked into position with nuts & bolts, tape or whatever. If they are not free to self align in the shaft it may create reduced lifetime before the pumps leak internally.
Anyone wanting to try out this highly teknikalogical advance in kiting - those old pumps you have discarded can generally be rejuvinated.
Pullout out the stem & stem seal; firmly reshape the sealing edge (finger pressure only required) ; regrease and rebuild. I like silicone based grease but others have other preferences.
Make sure the inner tube & all bits & pieces are washed clear of sand - you may have to resort to a pertol wash. Rinse thorougly with detergent before re-greasing in any case.

Convesely, the pumps could last longer if they ARE aligned giving them added structural integrity and support with resistance to bending... Lol

Thanks guys, gave the pump a mega cleanup and lube today. If it takes 170 next time, she's gonski.

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[quote/]Dave your pump is losing its "seal" mate.

Maybe it needs to go to the Tupperware party with the walrus,


to find a tight "seal"!!!

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Prawnhead said...
[quote/]Dave your pump is losing its "seal" mate.

Maybe it needs to go to the Tupperware party with the walrus,


to find a tight "seal"!!!

Have you ever blown a seal?