Isn't it quite possible the entire gun slammed into something, like the wall, and broke apart.I know if the valve smashed into my leg, I would have dropped or flung the entire thing as quick as possible...Cheekbone - Is there evidence the valve didn't enter the leg pin first?
Ok further down on that FB page is a gun from "Randy". I think these give us some clues how the extensions were assembled:
Pretty darn sure i would have flung it across the room in anger...
I'm just going by what he said. Maybe he was doped up on pain meds - didn't look it - and they had him confused, but he definitely pointed at the front of the valve and specifically stated that that was the end that went into his leg.
The male end of the extension can screw directly into the tube like it was made to go there, not. The bottom part of the unit has a collar the same dia. as the tube but where thr threads broke would be above the collar. At 4:13 i can see no collar left around the top of the tube. This makes for good reading on what I shouldn't attempt in the quest for more power. Powermax hasn't come through either. Three parties involved. Two no-shows and the third somewhere else.WOW! This is like the best forum out there. So much info to read through I'll never have to buy another book.
... Is this "creative ingenuity" ? ,or, "What the heck is going on with the scope mounting methods applied here" ? Is that JB Weld I see ?... ... and with a Flat head screw going through it no less ?Does this not speak volumes ?
Well like I said in this thread, and in my original reporting of what happened on the Powermax Network54 forum, it's a mystery just how it sealed. All I know for certain is that it did. The stock 2240 hammer spring failed to open the valve popped at 2,200psi, so I was stuck with a pressure vessel I needed to work on and no way to de-gas it. I did what Alex recommends to be done to relieve pressure safely; I slowly opened the connection between the HiPAC and the Crosman tube, hoping to let it start bleeding out... from what I thought would be the valve face/HiPAC point of contact whereupon the air would 'obviously' leak out around the valve body. It didn't occur to me to loosen the front grip frame bolt, and if it had, I probably wouldn't have tried loosening that anyway, as the prospect of a tiny bolt flying out with 2,200psi behind it would NOT be attractive! Since under 2,200psi the HiPAC was quite difficult to turn, and since I was more than a bit scared, I thought about it a fair bit then mounted it in my battered old aluminum soft jaws in the vise, figuring that a) this would avoid damaging the outer surface of the HiPAC tube, and b) the aluminum's inherent 'stickiness' would stand a good chance of holding it securely should anything decide to go one way or the other suddenly. The long version of the unscrewing story goes like this. I started turning the pistol using the secured grip frame for leverage, with the HiPAC secured in the vise. At first this was very difficult. It did not want to turn. I had used some white lithium grease (Campagnolo) on the threads to allow for easy assembly/disassembly, so it wasn't a question of dry steel on steel being sticky. Had to be all that pressure causing the threads to bind. But I persisted, estimating the amount of torque which was safe to use on the grip frame without snapping it, and fortunately finding I was able to move the thing before reaching that point. Gradually I unscrewed the pistol from the HiPAC and after about 2 turns it started getting much easier to turn. Within another 2 full turns it had become so easy it was as if there was no pressure at all, causing me to pause and worry for a few minutes. I knew there was still 2,200psi in there. There was no way that pressure had magically vanished. But I also knew there was now at least a 4mm to 6mm gap between the valve face and the HiPAC, and that seemed impossible. How could air possibly be sealed? The brass valve couldn't expand like a balloon and seal against the inside of the tube, could it? I had thinned the brass wall in the area, roughly 10mm long, behind the front threaded portion, to gain a bit more air volume in the valve. In doing that I had thought carefully about what degree of thinning was safe, and reasoned that since it was a threaded portion anyway there should be zero weakening of the valve wall if I only barely removed the threads, polishing the surface to remove the last traces of the thread valley. This might even, from my layman-machinist's understanding of engineering principles, even 'strengthen' that portion of the valve wall in the sense that by removing this sharply defined threading I had removed the stress risers all along that section. Perhaps magical thinking... but ever since working with Synchros in the late 1980's making high end mountainbike components (stems, bar end grips, forks and fork crowns, hand-carving prototypes etc.) I've held a keen awareness of the problem of stress risers in metal components. I round over practically everything, rarely leaving sharp transitions unless absolutely necessary, as many metals will fatigue and crack at such points in use. Anyway, I'd thinned the valve wall as described leaving that 10mm portion potentially able to expand the tiny distance to the tube wall and seal it. So I concluded after standing back for some minutes and worrying that this must have been what happened. Someone, can't remember who, told me that was not possible. I asked for an alternate explanation but didn't get one. I continued unscrewing the pistol from the HiPAC, double-checking to see that the HiPAC was quite tightly fitted in the vise, and checking again that nothing important, including any part of myself, was even close to in line with the main tube in case something went forward or backward in a hurry. Unscrewing continued to be easy until most of the HiPAC threads were exposed (going from memory as I hadn't measured them), then for the last little bit it got harder, quickly, until it was harder than initially. It seemed inevitable at this point that the threads on the main tube or the HiPAC would tear. I kept turning, forcing it open and in spite of the safety glasses turning my head and wincing... until BOOM! When I opened my eyes again I had the pistol in my hands, free from the HiPAC, and the HiPAC had shifted about 1/2" forward in the vise. Apparently the remnants of the black Powermax seal had blown out past the HiPAC into a rather messy storage corner under a drill press table, a place I still haven't really cleaned out since as it's just for rarely used bits of wood and metal and kind of hard to get into. My shop is very small and densely packed... So with the thing apart I went to my computer and emailed Alex about this. Got lippy answers. Went to his forum and spelled it out. Got more abuse. After a while I told him somewhat politely what I thought of his behaviour and stopped contributing to his forum. The internal machining marks in the HiPAC and the extension, the fact there was some sort of stiff red-brown gunk with metal flakes left in the extension tube which was very difficult to clean out, the fact that I had to re-work every sealing surface and make seals out of exotic materials (95durometer urethane for the fill poppet, ertalyte for the valve face seal) to get it to hold air, all make for a somewhat damning review of the product. But I did make it work and I am happy with the result, so I consider it to be raw material which proved useful for me. But I have sufficient skills to achieve such a result. I'd be willing to bet some cash that there are a fairly large number of HiPACs sitting around in people's abandoned airgun parts boxes when airgunners with less shop skill and patience have just given up. And sure, a lot of them work as-sold, and that's great. But using a really dull drill to bore out a steel rod for a pressure vessel just doesn't seem kosher to me. I mean seriously, the inside surfaces are grotesque, uglier than the inside of the cheapest steel tubing used for lawn furniture. If I ever take the thing apart again I'll have to try to figure out lighting and camera settings to capture just how bad it is. Alex's answer? He doesn't care how the inside looks, it doesn't have to be pretty. Oh boy.
I'm wondering why you didn't just hook your pump or tank back to the fitting, add a tiny bit of air and then "bleed" it by slowly opening the bleeder valve on your line
wow, now I will go back try to 'read' all of what Gerald is saying , but .....that was long and I have the A.D.D.,
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