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Posted: Mon Jun 30, 2008 1:57 pm
by Antonio
Nice job man! Its really inspiring me to build one as well. But yeah I really need a high pressure guage before I start working at higher pressures:)
Posted: Mon Jun 30, 2008 2:02 pm
by Sticky_Tape

Don't we have free health care Gipeto? well before the moddification I made on my first pump the shockys check blew out shot into my ceiling just missing my face. shockys like blamo I'm like

and my dad's like

yeah there was a dent in the ceiling of my room. With this pump I am hoping that it should open with the pressure or the bottom of the plunger.
Nice job man! Its really inspiring me to build one as well. But yeah I really need a high pressure guage before I start working at higher pressures:)
I didn't have a guage on my first pump the pump still functions the same I would count out the strokes I made and sometimes I would go a little over

.
I already soldered in the washer looks kinda crappy (olny my second time soldering but the joint is good I put on enough flux and the solder got in there and yes I roughend up the pipe and fitting.) I don't have a spring yet.
Posted: Mon Jun 30, 2008 4:15 pm
by Gippeto
That looks like it should work fine.
The piston should NOT be able to open the check valve. Air pressure will do this for you.
Keep up the good work. You're going to be REALLY happy with your new pump!
Posted: Mon Jun 30, 2008 4:30 pm
by Sticky_Tape
Why NOT?
Posted: Mon Jun 30, 2008 4:50 pm
by Gippeto
With the piston opening the check valve;
As you hit bottom, and start the "up" stroke, your check valve is being held open by the piston. This allows pressure to bleed back into the pump cylinder.
You already "worked" for that pressure, why bleed it off?
With air pressure opening the check valve;
As you approach bottom, the pump cylinder pressure opens the check valve. As soon as the pressure in the cylinder equals the pressure in the chamber plus that of the check valve spring (this is why a light spring is best), the check valve closes. Only residual pressure remains in the pump cylinder.
You had to "work" to make chamber pressure plus about 3 psi. That's not bad.
Using air pressure to open the check valve is simply more efficient.
Posted: Mon Jun 30, 2008 5:04 pm
by Sticky_Tape
So do you think that My pump will generate enough pressure to open the check?
Posted: Mon Jun 30, 2008 7:02 pm
by Sticky_Tape
sorry for the double post but I was trying to grind the washers and WTF there is alot of vibration and the washers get grinded unevenly no it is not off center everything is aligned and I am using a drill press does anybody have any other methods of making plungers?
Posted: Tue Jul 01, 2008 12:01 am
by Gippeto
I'm sure your pump will make enough pressure to open the check valve.
What are you using to "grind" the washers? I get that you are using a mandrel, but are you using a file, stone or? What type?
Posted: Tue Jul 01, 2008 7:48 am
by Sticky_Tape
8'' drill press on 3150 rpm, Mandrel, And 10'' Mill bastar d yeah that's what the file is called people give things pretty stupid names.
Posted: Tue Jul 01, 2008 11:18 am
by Gippeto
Slow it down (say 600rpm), and use a single cut mill file.
The file is chattering (jumping off of the surface and then biting down into it). Use light strokes and you'll get better results.
Posted: Wed Jul 02, 2008 10:35 am
by Sticky_Tape
Well I got the washers filed they fit in the 3/4'' with about a .5mm gap I don't need to take a picture do I?

Slowing dwn the press really made it easier Thanks Gip.
Posted: Wed Jul 09, 2008 8:40 am
by Sticky_Tape
I had a brain fart today I was removing the core of a shrader from my new project and I noticed that there is a rubber washer on the inside of the shrader removal tool on the other side of the wassher there is the tiny tube that removes the core. the shrader removal tool can screw onto shraders so I think I am going o use it as a adapter for my minis.
Posted: Thu Jul 10, 2008 10:42 am
by Sticky_Tape
well I bought the elbow I needed now all I need is:
pump plunger to be made, 3/4'' - 1/2'' threaded reducer 3/4'' being threaded you may not know what it is, and 3/8'' spring.
don't nag me about a guage I don't know where to buy one.
I am going to make the pump adaptable to shraders instead of just quick connects.
Posted: Fri Jul 11, 2008 9:28 am
by Sticky_Tape
Yesterday I took apart a old airsoft gun and took the spring from it I cut the spring to fit on the bolt and the check works great when I blow in less than 1psi with my lungs the check opens and when I suck back the check closes.
Posted: Fri Jul 11, 2008 1:00 pm
by psycix
Are you REALLY sure that that check valve wont blow when too much pressure is on it?
BTB got a failing checkvavle on a homemade pump remember? The punch of the pump handle acting as a pneumatic ram broke his jaw.