6 replies to this topic

[archangel24]

Recently acquired a leaky Splitfire. After taking it apart I found the leak, shitty dremel work caused a hole on the front of the left tank. Easy fix, right? Correct, but after maybe a couple days of dry firing to make sure no other leaks were present I noticed the infamous hiss. The right tank wasn't holding air due to the piston not sealing. Usual fix with back pressures is to flush the system with water to be sure there is no debris and pump fast. Worked for a short while but then clearing the water out (dry firing a shit ton of mist, this is KY so you're never firing dry) it stopped sealing again. The system is dry and clear of water now and it still will not seal properly and with the nature of Splitfire internals there isn't much to be done.

Tl;Dr right Splitfire tank piston isn't sealing and the usual methods aren't proving fruitful in the long run. Any other ideas? Did I miss anything? This is a backpressure tank so the normal methods should work but are difficult to execute well.

I even consulted the highest of the elder council of the numerous forests.

Because pictures make anything better.

Edited by archangel24, 26 January 2014 - 03:07 AM.

[Daniel Beaver]

Might be some debris in there that's preventing a proper seal.

[archangel24]

'Daniel Beaver', on 26 Jan 2014 - 12:18 PM, said:

Might be some debris in there that's preventing a proper seal.

If there indeed is debris left in the tank, any thoughts on what else could be tried?

[Blue]

Have you tried getting some silicone grease in there? Looks like you could use a bent q-tip (make sure you don't get cotton stuck in it, maybe cut off the tip) to get around the edges seeing as the barrels are completely gone. It's pretty thick and gummy which helps the piston seal to to the lip of the tank; but if you put too much it might have some issues with the backpressure pulling the seal back to release the air too slowly or not at all. Also consider soaking the tank in mineral oil overnight. Stay away from silicone sprays. Just suggestions; try at your own risk. I know how frustrating backpressure can be and sometimes it's just not salvageable.

[archangel24]

Thanks blue, I'll try that. Oddly enough this is the only time I've had problems like this with a backpressure tank. Actually drafting up designs to make splitfire internals, just trying to figure out the cheapest and easiest way to test them out jic it doesn't work out. It would actually be rather fitting if I managed to muster up homemade splitfire internals because of the plan that I have for this thing.

[shmmee]

'archangel24', on 27 Jan 2014 - 04:46 AM, said:

Thanks blue, I'll try that. Oddly enough this is the only time I've had problems like this with a backpressure tank. Actually drafting up designs to make splitfire internals, just trying to figure out the cheapest and easiest way to test them out jic it doesn't work out. It would actually be rather fitting if I managed to muster up homemade splitfire internals because of the plan that I have for this thing.

Home made back pressure tanks can be tough. I've opened up every style of back pressure tank I've owned for science. One constant I've noticed is that the outlet nozzle size (the surface the piston seals against)needs to be a smaller OD than the ID of the tube the piston rides on. If the outlet meets or exceeds the tube ID the piston won't slide back and all the tank pressure will vent back out of the piston stem.
Just something to keep in mind as you build.

Edited by shmmee, 27 January 2014 - 01:22 PM.

[archangel24]

Well shitfire, just replugged the pump an hour ago to get a higher pressure/volume of air into the tanks and after rapid dryfires, it seals again and a small bit of debris came out. So either the debris caused it or there wasn't enough pressure to seal the rubber that has been sitting in there circa 1999 or some combinations of problems that can arise from shitty work done on older nerf blasters. My thought is that it is the rubber on the pistons because there is a slight noise that I hear but I would assume that it is very methodically slow as the pressure doesn't drop after it's been sitting around for 10 minutes. But with he nature of the splitfire, it could be the piston seal or possibly the release valves(noticed air leaking out of them when taking it out of the shell but without the guides keeping them straight, it can be dismissed as anecdotally insignificant).
Abit off topic and relatively erotic but, my main concern for making homemade splitfire internals would be improving the release valves and maybe try and make it more of a dual action pivot trigger that actuates blast buttons(that way the spring isn't trying to hold the air in). But of course that would require a shell mod, new shells, or a homemade shell setup.

Either way, thank you all for your help and advice.