PCP pumps - Higher pressures than bicycle pumps
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- เผยแพร่เมื่อ 15 ก.ย. 2018
- WARNING: High Pressure Air is dangerous. Always use protection and caution when dealing with high pressure air.
This week we look at cheap Pre-Charged Pneumatic (PCP) pumps normally used for filling air guns and if they can be used for pressurising water rockets to higher pressures. We compare one of these to a regular bicycle pump. - วิทยาศาสตร์และเทคโนโลยี
Mate! Just found your channel, I grew up wth water rockets in Oz have lunched a few from the farm, nothing like yours but i see those cool designs and have had my interest rekindled! I'm subbing. Your place looks like where my folks live! Big balconies, palms everywhere.
I have a PCP rifle and agree its a lot of work to get the volumes required for even a 1.5 PET water rocket, small electric air compressor is best Great Video
ok as a model rocket enthusiast who recently also got a pcp pump and gun// WOW this is great stuff thanks so much!!
Thanks for posting this, George. I’m actually buying a PCP gun and your video has been far more informative than any gun related videos on these pumps I have seen. Also, I’m hoping to get back down under again soon, so will hopefully fly some more rockets with you then.
Hey Chris, Good to hear from you! :) It would be great to catch up again at a launch.
Finally George Katz pumping water rockets! Welcome to my Exhausting world!
Ha Ha :) I won't be giving up scuba tanks any time soon. This is way too much work! :P
Nice video about an interesting topic! :) I think the main advantage of an air pump is that it is very small, light and mobile. In contrast, compressors often need a power supply (car) and scuba bottles are very heavy. The air pump we use is limited to about 260 psi but it is really hard to get there, especially when the rocket is big. Filling a 9l rocket with 260psi requires a few team members to work together. ;) However, in the long term we plan to use scuba tanks as well to increase the maximum pressure further. ;)
I was wondering how you guys get up to the higher pressures. Is it a special air pump that can go that high? The PCP pump is really easy to pump at these lower pressures. When we used the plug that came with the pump we tried pressurising just the hose. It was when you got over 1000psi did it start becoming harder and at 3000psi you had to put your whole weight on the handle. Once you start using scuba tanks, you'll never look back. :)
We use an air pump specifically made for racing bicycles called "SKS Rennkompressor". It is very well built but we have changed the hose mount and mounted the hose additionally with a hose clamp to increase the pressure even more.
Good Job
It's incredible how cheaply these are available now. I remember playing about with spudguns years ago (mostly made from copper plumbing pipe) and I looked at one of these pumps for higher pressures, but they were over £150 at the time. I just checked EBay and there's some for as little as £30 - I might get one just as a bit of inspiration to have lying around ;-)
I too was surprised at how inexpensive these were. The build quality looks pretty good to me but I guess time will tell how quickly things wear out. I have seen YT videos people using these daily for months on end for their air guns and had no issues even with the cheap ones.
@@AirCommandRockets Thats my fear too, how quickly things wear out. I know nobody there was using PCP pump for longer time years or so. Let me know if you hawe experience or someone . Thank you and greeting form Hungary !
thanks, great video!
Did you ever need to service this particular pump? You can not enter the base of the pump to clean out the dirt with this particular model. You can do that with the model with the folding base, which is a little more expensive but also easier to fix.
We've not needed to service the pump yet. But good to know, thanks for the information.
Looks amazing and handles great...great power.Would definitely recommend to friends and anyone wanting an Ebike :-)
Hi George, interested to know how long and the number of strokes it took to achieve 80 psi in a 1.25L bottle for both pump types..
Hi Craig. From the measurements we got, it was about 240mL of air per stroke for the regular pump, and 180mL of air per stroke for the PCP one. Let's assume that a third of the volume of the 1.25L bottle will be water, that leaves about 0.83L of room for air. So at 80psi (5.5bar) that is 5.5 x 0.83 = 4.57L of air.
4.57 / 0.24 = 19 strokes with the regular pump and
4.57 / 0.18 = 25 strokes with the PCP pump.
We averaged about 2 seconds per stroke. (1 second up, 1 second down)
This was for the pumps tested in the video, other pumps will vary the amount of air they supply. You would also need to factor in the launcher and hose volume that also need to be pressurised.
omg, if you cant do maths, dont do rockets, and go to school instead.
What is the best pump that can pump to 150 psi but has really good air per stroke
Hi again George, do you think there’s any way that you modify a PCP pump, sacrificing the extreme pressure capability, increasing the output volume while maintaining the ease of pumping. Essentially, I’m hoping to achieve 2.5 litres, to 80psi, achieved by a child in a reasonable time frame/pump cycles. Any ideas? Cran
Hi, I am not sure how you would modify an existing PCP pump to get more volume. I am also not sure you would actually need to. With one of these pumps you get about 180mL of air per stroke. 2.5L at 80psi is around 13.5L of air. This would mean you would need about 75 easy strokes. A regular bicycle pump would take about 56 strokes but is more effort. If 1/3 of that 2.5L volume is water then you would need to make 1/3 less strokes to fill it up to that pressure.
would love to see it used for air tools
Using the pump directly to power air tools? The pump doesn't give enough volume of air, but you could first pump up an accumulator and then use the tools. Seems like a waste of energy though. You might as well use hand tools directly.
Water cooling to pump?
You could probably make the pumping effort a little easier, on the PCP pump, by removing the filter element.
Given it's a water rocket, you won't need to filter out any moisture, coming from the pump.
Fair enough point, though I suspect most of the effort is due to compressing the gas rather than due to the flow restriction of the filter.
@@AirCommandRockets To quote Tesco, "Every little helps". 😁
Can we use those pcp pumps to inflat a car or bike tyres?
Absolutely. They even come with standard size schrader valve attachments.
I have never herd of a pcp pump could I used it to fill a car tire or something to about 100-120 PSI? thoughts please thank you
Certainly, the PCP we bought even came with a Schrader valve attachment.
I mean I have a portable air tank that I am using m y standard bike pump get hard to pump around 100 PSI I guess you would need to make sure you have a guage on the device to have the right pressure is that right so than are you telling me that if I only need about 100-120 PSI it would be less strenuous to get one of these as it will fill more quickly but I guess your going to tell me you must carefully watch your gauages? so if I can afford it are you going to tell me I should replace my standard bike pump with one of these it will fill much quicker? thoughts please thank you
I wanted to know if you can use these to fill 5 or 10 gallon pressure tanks. Anyone know anything about that?
You should be able to, depending on what pressure you are going to will depend on how much effort you need to put in.
Put dry ice in your water rocket !
For about 200 u.s. you can get an electric young hang compressor much better will go to 4500 psi
These compressors sure would be useful for air guns, but for water rocketeers in the middle of a field without grid power makes them less practical. Also typically most water rockets need well under 1000psi.
I use a inverter and car battery
Your gonna need a huge garden or farm to usd tbe gun
I once launched my rocket at 120p with the first pump :D
I have pumped plastic bottle, and it becomes stone hard, you can kill someone by banging on head