K-mod Topic

C-A_99 · Post by **C-A_99** » Fri Sep 01, 2006 9:15 pm

Well my 30 balloon K mod on my 2100 mk2 didn't go so well. Around the 2nd (though often at the end of the first) pump, the pressure relief valve kicks in, leaving me with a quick shot. (though it's range seems to be fairly decent) This is part of the reason I didn't do a full K mod, something's going to go wrong and with a full K mod it would've been worse. I think I should take out about 10 balloons, will that do it?

The gun still leaks too. I submerged it in the sink and couldn't find anything. So far I'm guessing it might be in the pump but the pump is airtight and can pump air into the PC. A more likely possiblity is in one of the valves that's supposed to keep the PC's contents from returning to the rest of the system yet allow air/water to enter and pressurize the PC. Also, the red nozzle piece is not completely attached to the rest of the trigger, but the leak isn't really around that area. It probably flowed down into the middle maybe.

Silence · Post by **Silence** » Fri Sep 01, 2006 10:13 pm

Try taking out 5 balloons for now--you're almost certainly close to the point where the pressure release valve kicks in, and it isn't worth it to take out 10. Try pumping water and seeing where the leak comes out in air, instead of the other way around...who knows.

Are you sure it isn't leaking from where you pushed on the PC? There's no way it could leak from the check valve unless the actual tubing is cracked. Also, it doesn't need to be leaking from a crack in the internals...so think outside the box.

C-A_99 · Post by **C-A_99** » Fri Sep 01, 2006 10:33 pm

The PC seems to be snugged on well but I haven't checked that. I'll have to move my testing to the garage for fear of soaking everything in the bathroom. The leak seems to be more likely from the nozzle area than from the PC attachment though it was leaking in a similar way before I opened it up. It's possible that the nozzle area was already detached when I got the gun. I don't know anything about the gun's history and stuff since I got it from a friend about a month or 2 ago.

Edit: I took out 5 balloons and it made no difference to the behavior of the PRV. (the range really wasn't very good in the first place anyways, a primed XP310 shot a feet or 2 farther. I just need to resolve the PRV issue and get a full shot to see the true range) Also, since I had to reinforce the trigger with glue, it feels stiff when pulling it. (though it wasn't as stiff before I took out the balloons) For the leak, I'm sure it's the nozzle piece since I tested many other areas and didn't get leaks there.

Edit: The trigger piece got kind of messed up, then got repaired. The balloons were also removed, I simply didn't want to deal with the PRV acting up so soon, nor having to do a PRVF. The leak is also no more since the nozzle piece was glued back on. There's still some work on the trigger to do however, since the reinforcement on the trigger piece made it rather tight, so it still doesn't close up properly, even with the rubber band. (the trigger still gets stuck open unless I push it back with my finger)

To the PRV, I think the balloons were trimmed too much, which might have screwed up something. I'll get some pics soon.

Edit:

This is the nozzle piece I was talking about. Definately have to glue this one.

The balloons, I think they might have been overtrimmed. With 25 balloons, the PRV acts exactly as it did when I had 30.

Edit: I tried 20, same thing as usual. A valve is also leaky, the valve that keeps the pressure of the PC from returing to the rest of the system yet allows the pump to transfer water to the PC, so if I let it sit about a few seconds with 5 pumps, the pressure progressively depletes while it makes a weird noise. I think the gun wasn't cared for correctly and whoever used it tried to pump it too much, even when the PRV was going off, which might explain why the PRV is so sensitive (though it seems to be fine without any balloons) and the other valve.

JLspacemarine · Post by **JLspacemarine** » Sat Nov 11, 2006 7:15 pm

I'm trying to K-mod my CPS1200 but I can't open the PC because of rust. There are 6 screws that won't unscrew:

I can drill out these screws, but before I do anything fatal, I must think how I will be closing the PC back together. Any Ideas?

C-A_99 · Post by **C-A_99** » Sat Nov 11, 2006 9:17 pm

Maybe you could try a motorized screwdriver first but I'm not sure, I never had rusted and stuck screws before.

The PC itself won't even go back together with everything in the proper place without many of those screws. (the PC case doesn't wrap around the PC itself) If this doesn't apply to you 1200, it did to my 2100.

Silence · Post by **Silence** » Sat Nov 11, 2006 10:50 pm

If brute force and elbow grease doesn't work, and if the heads are messed up because of the rust and you don't have any of those pieces that are supposed to work for things like that, then you should drill these out. Really, don't worry about getting it back together--duct tape or something should do the trick in holding it. The point is to stop the bladder from expanding, not to create a seal.

DX · Post by DX » Sat Jun 09, 2007 5:40 pm

Recently, I have been testing various amounts of balloons with my 12K to see where the amount of pumps and balloons creates the most range. Contrary to what I first thought, more balloons does not mean more range in this case [all of this is with the PRV intact].

In general, ~5 balloons = 1ft of range IFF the amount of possible pumps remains constant. This works with very heavy K-mods, since I have used 10 or 15 pumps as a benchmark. However, the number of pumps changes when the PRV is still functional, so this doesn't work.

I started with the original mod of 45 balloons, which yielded a possible 12-13 pumps. Since the PRV kicked in at its limit [not the pump hitting a wall], the pc was nowhere near full. Stock pumping goes into the 20s or low 30s depending on the gun. Since I only have one 1200, I don't know what is usual for 1200 stock pumps. 45 balloons @ 13 pumps put the puddle at 44-46ft, last drop at about 48 [less than I guessed by eye]. These are still only approximate with 10ft markers, do not consider these accurate until I bring out the measuring tape.

When I opened the pc to change the number of balloons, the whole thing came off, all 45 in a clump. Putting balloons back on was annoying, so I started with 10. 10 balloons @ 24 pumps produced a puddle of 41-44, last drop of about 46. That wasn't the answer either.

So I tried something in the middle, 25 balloons. 25 balloons @ 19 pumps put the puddle at 45-47ft, with a last drop at 51.

Now I don't trust these too much, considering that the wind was acting up, crossing at a diagonal angle. However, it appears that a balance of balloons and pumps is the way to go. Too few balloons doesn't give you enough power, while too many doesn't let you use that power. For light K-modding, I would now recommend 20-35 balloons instead of my former [as many as you can get away with] answer.