PCP for no power situation let me hear your thoughts

[kristoff1313]

so I am one day going dark..(PCP AG) no way around it .. just not right now cause my wife would take the kids away and put me in an institution..I am just spit-balling here for now.

I like the shoebox clone i saw for HPA running off a nice sized AC motor very fast and quiet. I am wondering about no power options.

option 1 Would one be so inclined to use a hydrolic jack of sorts to push a piston enough on full piston stroke to fill the PCP AG in a direct fill manner (where dumped both chambers would be level 3k psi) Figure pump cylinder would be about twice the size of the AG tube volume.

option 2 (please don't laugh any harder than you might already be at my stupidity) stationary bike pushes the flywheel on a shoebox design gearing fan off pulley/fly wheel. no power, excersize and gets the job done.

[NJMevec]

Going to definitely be following this thread. I'm pretty intrigued as well.

From what I've read depending on what you're filling you'll be peddling a while. I would assume best way would just be to run a pump. Benji Pump or a Hill with a BUNCH of spare o-rings.

[45Bravo]

In the shoebox, I think you have to feed it with an air pump first, it just takes the pre-compressed air and compresses it to a higher pressure.


 I don't know if it will fill without it..

[rsterne]

It will fill, but much slower, and the automatic shutoff will not function properly....

Bob

[mobilemail]

Possibly think about a wind or water driven contraption?  Either one could convert circular to linear motion, and can work in your absence.

[Paul68]

Would heat be an issue in a one pump to 3k PSI scenario?

[kristoff1313]

wel lI was thinking if it is powered you can straight off start with a fridge compressor... I have a decent sized one here or can get another free from the recycling center and start with... the shoebox design is just a blueprint.. I dont want to buy it.. just want to start with that design.. larger flywheel, and make all three stages there or figure out the size piston cylinders and tube size to transfer to the next stage. I want all enclosed without power.. so if I need to pedal for 30 minutes ... so be it .. I need the exercise anyways. Then yes there is the matter of cooling which a belted fan could work.. or figure out some other way of charging like the motorcycle batteries I have and use them for cooling when I am done charging the tank or AG.

The shoebox needs the pre-charge due to the size it is made in I believe and can be worked around. I think they went that size for portability and cost effectiveness..(that is solely just an opinion/guess)

I am not sure what kind of gearing and auto clutching I would need for wind power plant... or powering by charged sources with solar and mechanical transfer. I want to keep it simple and cheap with what I can find scrap or trash.
I grabbed a free treadmill that works and is controlled by PCM knob that has a digital display. That may work for grid power..
Time to get together whit a couple engineering friends and see how feasible this can be. They looked at me like I was planning to kill myself when I stated 3k-4k PSI. "Yeah , yeah.. think paintball tanks boys.." hydro rated for my safety... now, how about the pistons and cables rating for those stages... Guess I got alot of homework to do.. the people that made similar designs are not sharing too much info..

That auto shut off.. yeah I need to figure out a trip for that off the pressure somehow...

[darren]

hows this......
shoebox and solar

[45Bravo]

How about the simplest answer to the problem.

Its a relatively new invention (oh say 400 years ago)

A high pressure hand pump.
you are talking about riding a bike for 30 minutes,
 I only have to pump for less than 5 minutes to refill my rifle..
Normally less than 3 minutes, and I pump slowly.

[Sfttailrdr46]

  4500 watt panel from HF about $150 just not sure that will do the job since you need a small oil less compressor to pre charge the Freedom8 to 120or 120 psi

[Sfttailrdr46]

How about the simplest answer to the problem.

Its a relatively new invention (oh say 400 years ago)

A high pressure hand pump.
you are talking about riding a bike for 30 minutes,
 I only have to pump for less than 5 minutes to refill my rifle..
Normally less than 3 minutes, and I pump slowly.

Kill joy     Actually Lewis and Clark carried a PCP Pellet rifle on their expedition and the information on it did not include a Freedom 8 setup, but I'm unashamedly lazy and prefer the High tec solution

[45Bravo]

Yea, I know it takes the challenge away of thinking out the box.


But sometimes the simplest solutions are the best solutions

[mobilemail]

 A gun with a low fill pressure like the Flying Dragon PCP or Benjamin Discovery will also make your task a little easier.

[kristoff1313]

@paul68 I am not sure since it would be small slow increments to build it up, and if so I would find a way to heat sink the chamber and cool it somehow.
@Darren shoebox design with solar could possibly work but not great in MN
@45bravo.. I have seen people posting  like 300 pumps to build up a rifle to their 3k setting and I am looking to fill a tank... ? pumps.
@mobilmail, I'm not sure what the discovery is rated at. if it is like 1000psi then I can squeek by tuning for a refrigerator compressor then running off batteries and an inverter.

My ideal project is to build a bigger shoebox design.. not purchase one.. and make it suit a motor and manual rotation of a flywheel. From what i have seen you can charge 5000 psi with this design fairly fast

I am inspired by youtube pjbarr1 and his clone if it gives you an idea of what I am thinking about.

[rsterne]

Think horsepower.... The ShoeBox only pumps 4 CF per hour and they run a 1/3 HP motor, presumably because a 1/4 HP isn't strong enough.... A good cyclist can generate about 0.4 HP over long periods of time, or just over 1/3 HP.... The motor on the ShoeBox doesn't have to run the primary compressor, so I think you'd be lucky to deliver 4 CF per hour at 3K-4K by cycling.... That would take you 20 hours of strenuous pedaling to fill an 80 CF SCUBA tank....

All I can say is, better you than me....

Bob

[kristoff1313]

@rsterne you make an interesting claim here. with a  compressor I don't have.. and a shoebox I don't own. I will go along with it pumps 4cf per hour.  1/3 HP peak or RMS motor make a difference. 1/3 peak could be more like 1/4 RMS or less power depending on design and manufacturing. The shoebox is small.. so it fits in a backpack or portable in nature. It can fill 64CI in 1.5 hours with its size. (HPA Paintball Tank... NOT scuba tank as I wouldn't drag that steel anchor around in the woods..)

Now I think the design can go larger.. can make a heavier flywheel and the maintaining inertia from cycling can be geared accordingly. I think a first stage can be built in as well.

If I go powered it could be easier.. rip a working compressor off a thrown fridge if it was a freon leak issue and not bad compressor (recycling center free). I have one in the garage already I was going to look into air brushing.
Rip a large motor off a working treadmill (recycling center again) Or use the one that was for free on the neighbors front lawn earlier this summer that is sitting in my basement. Was thinking of making a poor mans lathe.. I don't want to work with that much cement and rebar...

I still haven't ruled out using hydraulic jack to piston pump the high pressure stage with check valve on the small scale fill station. That could possibly be easier and less parts to it.

[Gertrude]

4500 watt panel from HF about $150 just not sure that will do the job since you need a small oil less compressor to pre charge the Freedom8 to 120or 120 psi

Don,
correct me if I am wrong, but...

...I think you may have (2) too many zero's on the wattage of that HF panel set of which you speak, for $150.

 4500 watts will easily run my wire feed welder, (maybe with my A/C going too).
    

[Sfttailrdr46]

4500 watt panel from HF about $150 just not sure that will do the job since you need a small oil less compressor to pre charge the Freedom8 to 120or 120 psi

Don,
correct me if I am wrong, but...

...I think you may have (2) too many zero's on the wattage of that HF panel set of which you speak, for $150.

 4500 watts will easily run my wire feed welder, (maybe with my A/C going too).
    

Oops !! I stand corrected it is 45 watts I guess you would need a few to do the job

[45Bravo]

Ok, I am going to say it here,   PSI IS THE NEW FPS...

in airgun sales the FPS rating has been THE selling point to a new or non airgun person.

You have 2 identical rifles, one rated at 950 FPS (small letters beside that * with lead pellets)
And another right beside it rated at 1000 FPS ( small letters beside that * with PBA pellets)

The 1000 FPS rifle will outsell the other.

Lately, because of the shortage of rimfire ammo, and higher cost of regular ammo.
People are turning to air guns, and they research and learn a little about PCP guns.

To them, they think
"certainly a gun that fills to 3000 psi has got to be a better gun than one that fills to 2000 psi.."

Just because it is rated at a certain pressure, doesn't mean it runs best at that pressure..

The marauder is rated at 3000, but in the instruction manual it even tells you it is tuned for ~2500 psi.

I have a B 50 in .22. It is rated for 3000 psi, but it turns 800+ FPS on 1500 psi for over 30 shots.

3000 FPS only gets me 900 FPS, with less shots, and less accuracy and harder to pump to 3000.


When someone markets a air gun rated at 4500 psi, at a comparable price to a 3000 psi gun,
 it will sell like hot cakes.

Never mind, at full pressure, you MIGHT get 1 full pressure top off with your fresh 4500cf tank.
People will buy it for the bragging rights to say their gun can use up to 4500 psi.

And they perceive the added benefit of the fill pressure.

Now, if you are running a regulator in your gun, then the extra psi is great,
it does mean more shots per fill, and then 3000 or 4500 is a viable selling point,
other than the difficulty of getting it back to that fill pressure without a shoebox compressor
after you shoot it down..

[Ol'DeadEye]

I kinda like the idea of a steam engine to power both a low pressure compressor and a shoebox (or equivalent) compressor.

Uses just water and wood, like the neighbors fence, in case of electric grid failure.

Just takes some ingenuity to design the pulley sizes to provide the power to the compressors.

Oops, I think I spent too much time at an antique engine museum.

Maybe I'll continue to use my manual pump...