Garspeed
10-04-2017, 10:43 AM
Okay, so it has been a long time coming but here goes. Let me start by saying sorry to the JJ masses who think that this unit is perfect, please don't seek me out and string me up!
I have been diving the JJ for just shy of one year now and having come from an AP unit think that the engineering is beautiful. That said, she is far from perfect and amongst my pet hates / annoyances are as follows...
- threads to engage scrubber to head are crap and continually cross mesh
- head engagement into can is not great, in fact it can be a ball ache to install and remove
- wet contacts on both hud and handset are a pain (new version units have fix I believe but this cannot be upgraded in old ones)
- inhale lung cannot easily be cleaned
- cannot fit suit inflate bigger than 1 litre onto backplate due to RMCL's becoming obstructed
- no matter what the fashion police tell you, RMCL's will never breath as good as TOS due to static imbalance
So the majority of above I can do nothing to fix, but the last few issues relating to the lungs, hmm! As some of you may know, I have experimented with Inspo lung builds for several years now and have made RMCL's, TOS and hybrids. Looking at the JJ issues the obvious solution to many of my issues was to build my own TOS lungs. If done to fit from top of backplate to front d rings then this should allow 1.5 litre alloy suit inflate onto backplate, torch battery on opposite side, if extra dump is added then I can clean both lungs easily, simples!
So with plan set I got out the pen and started doodling. I also got out the calculator and started working out lung volumes that seemed more appropriate to my size. The results of my efforts are shown below...
New inner bags with existing holes sealed up and new ones made on opposite side
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1359_zpsmufm2y6x.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1359_zpsmufm2y6x.jpg.html)
New outer bags
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1354_zpssqeujo6a.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1354_zpssqeujo6a.jpg.html)
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1353_zpsxl92jril.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1353_zpsxl92jril.jpg.html)
Completed build on new lungs (note dumps now on inhale and exhale lungs)
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1366_zpsc0a8adpc.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1366_zpsc0a8adpc.jpg.html)
Hope you like the lungs, I have more photo's to upload on how they fit onto harness and how harness and lungs fit onto unit but for some reason my host program is not playing ball. I will try again later and add to this thread with more photo's if possible.
For info, two test dives completed this weekend in quarry to 22m and lungs were perfect. No issues with ADV firing early, or dump valves releasing prematurely so volume of outer bag seems good. Also attempted off loop bailout in both head up and horizontal positions and found that the lungs self vented on ascent each time with no loss of buoyancy control ie I can surface safely without having to manually pull strings to dump loop. So far so good, but real test will be deep dive once weather improves. That said, on route home from last quarry dive my buddy and I skirted around a shallow ledge at 3-4m deep which is already a pretty good test of buoyancy control!
I have been diving the JJ for just shy of one year now and having come from an AP unit think that the engineering is beautiful. That said, she is far from perfect and amongst my pet hates / annoyances are as follows...
- threads to engage scrubber to head are crap and continually cross mesh
- head engagement into can is not great, in fact it can be a ball ache to install and remove
- wet contacts on both hud and handset are a pain (new version units have fix I believe but this cannot be upgraded in old ones)
- inhale lung cannot easily be cleaned
- cannot fit suit inflate bigger than 1 litre onto backplate due to RMCL's becoming obstructed
- no matter what the fashion police tell you, RMCL's will never breath as good as TOS due to static imbalance
So the majority of above I can do nothing to fix, but the last few issues relating to the lungs, hmm! As some of you may know, I have experimented with Inspo lung builds for several years now and have made RMCL's, TOS and hybrids. Looking at the JJ issues the obvious solution to many of my issues was to build my own TOS lungs. If done to fit from top of backplate to front d rings then this should allow 1.5 litre alloy suit inflate onto backplate, torch battery on opposite side, if extra dump is added then I can clean both lungs easily, simples!
So with plan set I got out the pen and started doodling. I also got out the calculator and started working out lung volumes that seemed more appropriate to my size. The results of my efforts are shown below...
New inner bags with existing holes sealed up and new ones made on opposite side
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1359_zpsmufm2y6x.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1359_zpsmufm2y6x.jpg.html)
New outer bags
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1354_zpssqeujo6a.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1354_zpssqeujo6a.jpg.html)
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1353_zpsxl92jril.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1353_zpsxl92jril.jpg.html)
Completed build on new lungs (note dumps now on inhale and exhale lungs)
http://i1352.photobucket.com/albums/q658/Garspeed/JJ%20TOS%20Lungs/IMG_1366_zpsc0a8adpc.jpg (http://s1352.photobucket.com/user/Garspeed/media/JJ%20TOS%20Lungs/IMG_1366_zpsc0a8adpc.jpg.html)
Hope you like the lungs, I have more photo's to upload on how they fit onto harness and how harness and lungs fit onto unit but for some reason my host program is not playing ball. I will try again later and add to this thread with more photo's if possible.
For info, two test dives completed this weekend in quarry to 22m and lungs were perfect. No issues with ADV firing early, or dump valves releasing prematurely so volume of outer bag seems good. Also attempted off loop bailout in both head up and horizontal positions and found that the lungs self vented on ascent each time with no loss of buoyancy control ie I can surface safely without having to manually pull strings to dump loop. So far so good, but real test will be deep dive once weather improves. That said, on route home from last quarry dive my buddy and I skirted around a shallow ledge at 3-4m deep which is already a pretty good test of buoyancy control!