Airgun hand pump - 200bar

[The Sky Dart]

This is for someone who might be interested in getting above 100psi.
http://www.fxairguns.com/accessories.asp

[The Sky Dart]

After a failure of the first test flight of our new rocket reported elsewhere on the forum, we are seriously thinking about investing money into an airgun pump of one type or another. Taking into account quality of the product and its potential capabilities this seams to be a right way forward even though only 10% of the pump potential will be utilised.

However, there is one element, I'm not clear about at the moment and I hope someone on the forum could explain it to me or point out to a source on the Internet.

I'll need to get from 1/8 B.S.P female connector on the pump to an air hose of some sort and to a valve on the launcher. I don't know what type and size of valves and fitting I have to look for. Does any one know a
a supplier in the UK where I can find the necessary bits and pieces.

[rockets-in-brighton]

After a failure of the first test flight of our new rocket reported elsewhere on the forum, we are seriously thinking about investing money into an airgun pump of one type or another. Taking into account quality of the product and its potential capabilities this seams to be a right way forward even though only 10% of the pump potential will be utilised.

However, there is one element, I'm not clear about at the moment and I hope someone on the forum could explain it to me or point out to a source on the Internet.

I'll need to get from 1/8 B.S.P female connector on the pump to an air hose of some sort and to a valve on the launcher. I don't know what type and size of valves and fitting I have to look for. Does any one know a
a supplier in the UK where I can find the necessary bits and pieces.

For reference...

http://www.airlines-pneumatics.co.uk/ These guys have everything, but their postage & packing costs are crippling for small orders. Good for seeing what is available, then you can shop around. You may even be able to get this sort of stuff from a DIY store.

http://www.hosefit.co.uk/catalog/ These guys have a smaller range but a more reasonable postage & packing scheme.

If you are happy making up the air hose yourself buy a 1/8" BSP male hosetail to fit the inside diameter (I/D) of your air hose, see these for example: http://www.airlines-pneumatics.co.uk/we ... de=S010143.

At the launcher end, I chopped the adaptor and a short length of hose from my bike pump and used a hosetail adaptor to join it to the main air line e.g. one of these http://www.airlines-pneumatics.co.uk/we ... de=S010148 chosen to suit your hose sizes. Each end also needs 2 x hose clips ("jubilee clips") to secure the fittings.

I went with plastic fittings, wish I had chosen brass now because they crush easily.

[The Sky Dart]

Brilliant! Thank you very much. This certainly points me in the right direction.

[sonbakler]

This is for someone who might be interested in getting above 100psi.
http://www.fxairguns.com/accessories.asp

They're interested, I need the Shrouded barrel and barrelsupport for my gun.

[160psi]

The problem with an airgun pump is that the volume pumped is so very small that it would take forever to pump up a water rocket. Typical pneumatic air rifles have a capacity of around 100cc in the reservoir and mine takes about 40 pumps to increase the pressure from 120bar (discharged) to 180bar (charged). Therefore each pump stroke is increasing pressure by 1.5 bar. On a 2 litre bottle this would mean that 20 pump strokes would be needed for a 1.5 bar change so to get to 220psi or 15bar would take 200 strokes.

Even if my maths is out it would still take a long time, but could be used on a small rocket for "topping up" after the limit of the main pump had been reached.

[U.S. Water Rockets1]

The problem with an airgun pump is that the volume pumped is so very small that it would take forever to pump up a water rocket. Typical pneumatic air rifles have a capacity of around 100cc in the reservoir and mine takes about 40 pumps to increase the pressure from 120bar (discharged) to 180bar (charged). Therefore each pump stroke is increasing pressure by 1.5 bar. On a 2 litre bottle this would mean that 20 pump strokes would be needed for a 1.5 bar change so to get to 220psi or 15bar would take 200 strokes.

Even if my maths is out it would still take a long time, but could be used on a small rocket for "topping up" after the limit of the main pump had been reached.

You need to build some way to motorize the pumping action, so you could just let it run by itself without human effort. Even if the volume was small in the pump, not needing a person hand pumping would make it seem a lot faster.

[Skymeat]

There has been a lot of talk about motorizing these pumps on the airgun forums. No winners as they fail fairly quickly.

When you're filling it generated a LOT of heat which ruins the seals. Also you're using your body weight to compress the last few strokes. I can fill my aa410 in about 5 minutes. That's about a 200cc reservoir that's not drawn down to below 1000psi and goes to 2900.

The pump will get to 200 bar, but with a lot of work, and you have to let heat dissipate.

I'm using a Hill pump, which is just a copy of all the others out there, and it has a machined body and heavy coating. It's a burly device. But I would recommend against trying to motorize it, just take your time as it's possible to fill a decent sized volume.

[Team Seneca]

There has been a lot of talk about motorizing these pumps on the airgun forums. No winners as they fail fairly quickly.

When you're filling it generated a LOT of heat which ruins the seals. Also you're using your body weight to compress the last few strokes. I can fill my aa410 in about 5 minutes. That's about a 200cc reservoir that's not drawn down to below 1000psi and goes to 2900.

The pump will get to 200 bar, but with a lot of work, and you have to let heat dissipate.

I'm using a Hill pump, which is just a copy of all the others out there, and it has a machined body and heavy coating. It's a burly device. But I would recommend against trying to motorize it, just take your time as it's possible to fill a decent sized volume.

Would it be possible to add some sort of cooling fins to the pump? I have tons of aluminum strps that could be welded on and draw the heat away.

[WRA2]

There has been a lot of talk about motorizing these pumps on the airgun forums. No winners as they fail fairly quickly.

When you're filling it generated a LOT of heat which ruins the seals. Also you're using your body weight to compress the last few strokes. I can fill my aa410 in about 5 minutes. That's about a 200cc reservoir that's not drawn down to below 1000psi and goes to 2900.

The pump will get to 200 bar, but with a lot of work, and you have to let heat dissipate.

I'm using a Hill pump, which is just a copy of all the others out there, and it has a machined body and heavy coating. It's a burly device. But I would recommend against trying to motorize it, just take your time as it's possible to fill a decent sized volume.

I believe that there has been discussion before on using a 12v compressor like the kind used to inflate car tires (most of which can pressurize to 200PSI without problems) to get the rocket up to pressure and then using one of these high pressure hand pumps to "take it further". that saves a lot of work with the low volume of the high pressure hand pump.

[Team Seneca]

I had another idea. How about puttin the pump inside a water tank and putting an intake snorkel hose outside to collect air. The water would act like a "cooling jacket". I bet that would help a lot.