Air Venturi G6 pump with booster....

[TerryH]

I posted this mod for the G6 pump in my Armada thread but I thought I'd split out the pump mod into it's own thread since it's kinda buried in that thread. Hope it is helpful to someone. I did the mods to the G6 pump to use my little pancake compressor as a booster. Took a little doing. Much more of a project than it is for the Benji pump but I think the results were worth it.

The G6 pump pulls air through the handle so the first order of business was to remove the hand grips and and see what's going on inside there.

First thing I see is a little black block of mesh...



When I pull out the block of mesh much to my surprise, I see that the handles are full of desiccant beads. Pretty cool idea but they weren't doing a very good job as I was feeling some moisture when I released the bleeder after pumping.





After removing the beads and mesh filters, I measured the id of the handle tube and determined that it I could drill it to 3/4" and tap it to 1/2"npt. I picked up the necessary fittings from Lowe's and a little desiccant inline filter from Harbor Freight.

Here are the fittings. 1 - 1/2"npt x 1/2"npt male, 1 - 1/2"npt x 1/4" npt reducer and 1 - 1/2"npt pipe plug.



And the filter and a 90 degree air swivel I also picked up from HF. A 1/4"npt x 1/4"npt male fitting will also be required.



Here's the handle tube drilled to 3/4" id. Both ends of the handle have to be drilled and tapped.



One end of the handle will receive the 1/2"npt plug. In the other half of the handle I reinstalled the mesh plugs and the desiccant beads once both ends were tapped before installing the 1/2" x 1/2" male fitting.

 



Here's the completed plugged end. 



And after the hand grip was trimmed to clear and installed.



And here's the business end with the 1/2" x 1/2" male installed into the tapped handle end and the 1/2" x 1/4" reducer installed.



I added the 90 degree swivel fitting to mount the desiccant filter so it could move freely during the pump stroke. The filter will stay with the pump so I can have the added air drying whether I'm using the booster compressor or not. I added a regular type N foster fitting to connect the compressor.



I have a 5hp 80 gallon Snap On compressor for my shop needs but I opted to use the little Harbor Freight pancake compressor that we use at the race track. It's oil less and obviously portable. I have the output regulated down to 15-20 psi. for this application.



After all of that, the proof is in the pudding so I hooked it up and began pumping. The stock pump took about 100 pumps or so to go from 2000psi to 3000psi. With the booster pump that number is cut in half with only 52 pumps to gain the same 1000psi.

Here is the completed setup in use. I'm quite happy with the results. The pumps do require a bit more effort with the booster but the number of pumps being cut in half way more than balances that out.



Once I started using the boosted pump I discovered that the bolts attaching the handle to the shaft leaked like crazy since the handle is now pressurized. I filed the mating surface flat and cut a couple of slices off a nylon spacer that I had to make 2 nylon washers to form a seal for the bolts to the handle.

[Wayne52]

That's a nice setup ya got there Terry, that will keep the pump cool as well because the amount of movement is cut right in half, that would worth buying one of those pancake compressor's just to do that with. 

[TerryH]

That's a nice setup ya got there Terry, that will keep the pump cool as well because the amount of movement is cut right in half, that would worth buying one of those pancake compressor's just to do that with.

Thanks Wayne! The little $50 Harbor Freight compressor has come in handy for many things. I use it all the time.

[jus Tom]

Superbly illustrated post Terry!  I have a G6 also and for the past few months using it, have also noticed slight moisture collection expelled when bleeding it off. 
In my reading here and other places about reducing moisture with external bead filtration, I also considered installing those same filters, simply stuck into the handle ends without doing all the plumbing,, logically it should work as the air has to enter through the least restricted route, the filter.
THEN I came across a post by someone wiser, (with more years of pcp use / pumping than I), and he brought to light the "actual" duration of the air passing through these small filters is so minimal that there was little evidence they did any good at all. That post made me abandon any thoughts I had, so I bought a tank.
I'm hoping to see follow-up reports of your findings, with the compressor assist, the G6 works less, but air is still drawn from the atmosphere you're in and it does heat up a little causing the humidity. Curious to know how much less moisture you found when bleeding off?

[Rodeo]

I have been using the "supercharged" pump idea with my G6 for almost a year now with great results.  I have a slightly different setup.  I use a 10gal air storage tank that holds 150psi compressed air instead of feeding from a compressor.   Inside of the tank I have 5lbs of silicone desiccant.   I have a regulator and paint spray gun filter on the tank that feeds the pressurized air to the G6 pump.  This setup does cost a little more but I get some benefits:
- When I pressurize the holding tank my compressor removes most of the moisture (I have a basic moisture/filter trap on my compressor).
- The compressed air stays in contact with the desiccant allowing for maximum moisture removal.
- I do not have to listen to the compressor running while pumping.
- Very little weight added to pump and no worry of breaking anything if pump falls over.
- Lighter and more portable than a compressor.
I fill my 90ci 4500psi bottle with this.  I start at 20 to 25 psi input to the pump and reduce to about 15 psi with the regulator when bottle pressure gets around 4000psi.  It does require more effort for each pump but the amount of pumping is WAY less.  Like Terry said the hardest part was modifying the pump handle to plumb the pressurized air to it.  I used a nylon 3/4 pipe thread to 3/8 barb elbow to make the connection.  I have never found any moisture or contaminants  in my guns using this.

[TerryH]

Superbly illustrated post Terry!  I have a G6 also and for the past few months using it, have also noticed slight moisture collection expelled when bleeding it off. 
In my reading here and other places about reducing moisture with external bead filtration, I also considered installing those same filters, simply stuck into the handle ends without doing all the plumbing,, logically it should work as the air has to enter through the least restricted route, the filter.
THEN I came across a post by someone wiser, (with more years of pcp use / pumping than I), and he brought to light the "actual" duration of the air passing through these small filters is so minimal that there was little evidence they did any good at all. That post made me abandon any thoughts I had, so I bought a tank.
I'm hoping to see follow-up reports of your findings, with the compressor assist, the G6 works less, but air is still drawn from the atmosphere you're in and it does heat up a little causing the humidity. Curious to know how much less moisture you found when bleeding off?

Have virtually zero moisture at the bleeder now. Was a pretty significant amount before. I've pumped up about 10 or so times and the desiccant in the HF filter needs to be changed/dried so I believe it is working well.

[TerryH]

I have been using the "supercharged" pump idea with my G6 for almost a year now with great results.  I have a slightly different setup.  I use a 10gal air storage tank that holds 150psi compressed air instead of feeding from a compressor.   Inside of the tank I have 5lbs of silicone desiccant.   I have a regulator and paint spray gun filter on the tank that feeds the pressurized air to the G6 pump.  This setup does cost a little more but I get some benefits:
- When I pressurize the holding tank my compressor removes most of the moisture (I have a basic moisture/filter trap on my compressor).
- The compressed air stays in contact with the desiccant allowing for maximum moisture removal.
- I do not have to listen to the compressor running while pumping.
- Very little weight added to pump and no worry of breaking anything if pump falls over.
- Lighter and more portable than a compressor.
I fill my 90ci 4500psi bottle with this.  I start at 20 to 25 psi input to the pump and reduce to about 15 psi with the regulator when bottle pressure gets around 4000psi.  It does require more effort for each pump but the amount of pumping is WAY less.  Like Terry said the hardest part was modifying the pump handle to plumb the pressurized air to it.  I used a nylon 3/4 pipe thread to 3/8 barb elbow to make the connection.  I have never found any moisture or contaminants  in my guns using this.

Thanks for posting, Curtis! Good to hear a report from someone that's been doing it for a good while.

[Rodeo]

I had the same issue with the handle attachment bolts leaking.  I had to seal the top of the bolts going into the handle as well as between the handle and pump cylinder top plug.  Took me a couple of tries to find a material that was soft enough to seal yet hard enough to withstand the repeated force of pumping.  Finally settled on a red rubber gasket material I found at Home Depot.  I am not getting any moisture collecting in the bottom of the pump but I am getting some of the silicone lubricating grease there.  I removed the glass beads from this area and replaced them with the packing foam from inside of a pellet tin.  The foam traps the excess grease and makes maintenance cleaning of that area of the pump easier.  I might be a little too generous with the lube.

[mr.grimm]

I use a boosted Benjamin pump to fill my FX Gladiator with 680cc reservoir. Will only pump with a boosted pump. I run my supply pressure @ 30psi and it cut my number of strokes by about 2/3rds. A boosted hand pump is the only way to pump.

[Rodeo]

Finally remembered to count the strokes when filling my 90ci Air Venturi tank with the supercharged G6 pump.  Filling from 3500 to 4500psi took 185 pumps.  Input pressure to the pump was 20psi.  The 180 strokes includes the pumps to bring the G6 up to pressure at the start and after taking a break after the first 100 strokes.

[Back_Roads]

Just for comparison, it takes about that many pumps to fill an empty Sam Yang Recluse 500 cc gun from empty, to 3000 PSI with out a booster on the hand pump.

[Rob M]

the best illustration of boosting a hand pump ive ever seen..a very good tutorial..

[A.K.A. Tommy Boy]

I Agree with Rob M.    This is Real Good Stuff Here !

[Rodeo]

Someday I would like to get a compressor, but every time I look into them I see $$ for a new gun instead.

[TerryH]

the best illustration of boosting a hand pump ive ever seen..a very good tutorial..

Thanks. I enjoy the process.

Terry

[Elroy01]

Thats something im ganna try Thanks for posting