GTA
Support Equipment For PCP/HPA/CO2 and springers ,rams => Support Equipment For PCP/HPA/CO2 => Topic started by: Tweeter on August 19, 2018, 03:28:41 PM
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I noticed that there are some marks on my air venturi male foster fitting. I have this connected to the gold female fitting on the small filter and it is a little loose. Not terribly loose but I think it is whats causing this? I would just thread my microbore hose directly onto the blue filter but the threads are different and am not going to risk that.
Are these marks normal or should I find another way to connect everything? Hopefully the picture is good enough...
(https://i.imgur.com/tKVCmcb.jpg)
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What marks?
Where the black paint is wearing off?
Normal
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probably done from normal use....mine is loose also, but the sealing of the
probe is fine.
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Are you referring to the small shiny dimples on the shoulder of the QD? Seems normal, but if it worries you perhaps get a now male end to put your mind at ease.
Just checked my two most commonly used male QD fittings both exhibit the same dimples, more so on my brass ataman fill probe, just seems to be caused by the extreme pressure and forces involved with our air guns.
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Are you referring to the small shiny dimples on the shoulder of the QD? Seems normal, but if it worries you perhaps get a now male end to put your mind at ease.
Just checked my two most commonly used male QD fittings both exhibit the same dimples, more so on my brass ataman fill probe, just seems to be caused by the extreme pressure and forces involved with our air guns.
Yes the dimples on the shoulder. I should have described it better, thanks! Good idea, I'll order a new one. A few bucks for peace of mind is worth it. I already wear body armor when I fill my guns with this thing, I look like an EOD tech. haha.
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probably done from normal use....mine is loose also, but the sealing of the
probe is fine.
Mine seals fine with the Air Venturi male foster but the foster on my fill probe fits so loose that it leaks. Thanks for the response.
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Those dimples are from the small balls in the locking mechanism of the foster fitting. I was a little shocked to see them on yours, but I just took a look at mine and it has them too!
Mine aren't so easy to see, though, being a little smaller and on a piece made out of brass with no paint. That size difference might be due to the hardness difference between brass and aluminum, and maybe the pressure. I pump mine to about 3300 PSI max. What pressure do you go to in your system.
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Both of my fosters have been brought right to 300 bar between the leshiy and the AP16, many times and are approaching the depth/prominence of Tweeter's. Hope they don't become a routine wear item . . .
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Those dimples are from the small balls in the locking mechanism of the foster fitting. I was a little shocked to see them on yours, but I just took a look at mine and it has them too!
Mine aren't so easy to see, though, being a little smaller and on a piece made out of brass with no paint. That size difference might be due to the hardness difference between brass and aluminum, and maybe the pressure. I pump mine to about 3300 PSI max. What pressure do you go to in your system.
I pump my gun to 250bar max about 3600psi. I don't even dare take this compressor to 4500, let alone the fill hose... When I noticed them I was a little worried but after looking at the fittings it would basically have to explode for it to come apart. I will use it carefully until I get the replacement but I think it is okay and seems to be normal.
I think it is the slightly loose fit of the chinese part that is causing it to happen because I've never seen this on any of the male foster fittings on my fill probes.
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chinese products are good, i think most of our fittings are made in china, what we get here is made in china but high quality,,qf in the pic is filter for my yh, its exposed to 4200psi everytime i top off my scba tank
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There is already a thread on the brass versions failing. If steel dimples, brass hasn't a chance. My airventuri probe foster attachment is blackened steel. Not alu. as posted here.
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I have never seen such deep dimples in a male Foster.... That would make me very nervous.... Brass is NOT recommended for high pressures, it is intended for connecting paintball hoses running 850 psi.... Even the steel Foster brand name fittings come in two grades, and only the best one is rated for 4500-5000 psi....
Do you have any idea what material that male QD fitting is made from?....
Bob
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I was thinking the same thing as Bob because I have a double male steel fitting that I get my tanks filled with when I have the adapter on the tank and it takes 4600psi every time I get it fill and there's hardly any markings on it. Even the brass probe that I fill my SPA M16 with isn't near as bad looking as the one in the picture above. I fill that to 3600psi every time.
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I was thinking the same thing as Bob because I have a double male steel fitting that I get my tanks filled with when I have the adapter on the tank and it takes 4600psi every time I get it fill and there's hardly any markings on it. Even the brass probe that I fill my SPA M16 with isn't near as bad looking as the one in the picture above. I fill that to 3600psi every time.
Thanks for posting picture of a steel unit, Wayne. Looking at the picture, I can see the faintest of marks on that one too, but definitely nothing compared to Justin's unit. I suspect his to painted aluminum as they are somewhat deeper than what I can see on my brass unit.
Here is an assignment for some one: calculate (a) the force the on the Foster connection (just cross section surface area and pressure, I think), (b) the load per ball (which is compounded by the angles), and (c) the contact stress under said ball of whatever radius it is when against the fitting. That last one is essentially similar to contact stresses of ball bearings.
We can probably guess what that tells us. Will it fail? Probably not, as it has to get through a lot of metal to actually shear away. Issues might includes flakes of metal eventually coming loose, but I suspect that is more of a problem for rolling contact. However, maybe we should be asking what is happening to the other side of that fitting. If cheaply made it is taking just as many dings as the fitting. And the balls. If they are good steel bearings, then they too are taking a beating. Are the stresses enough that they might start breaking up? Again, certainly an issue for rolling applications, but I'm not sure about this case. I guess we need to see the load and stress calculations.
Solution: don't use small balls on essentially flat surfaces. Larger balls would help a lot. More balls. Maybe grind a little race for the balls to mate to? Actually any DIY type could try that one and get us a report :) Beyond that it gets kind of weird and expensive...like come up with a version that uses roller bearings or some sort of wedge, i.e. larger contact area. At lower pressure the ball bearings get us a fitting that can swivel. With dimples like that, I suspect that motion is not happening. If that is the case, then maybe we don't need it in the design in the first place.
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To be truthful, I would be more concerned of the brass female doing the same thing inside where you can't see it.... Eventually that could cause the balls to dislodge and then the male would depart at whatever pressure was behind it at the time.... :o
When you see dents like that in anything under pressure, the load is exceeding the yield strength of the material under stress.... That is pushing that material immediately into the zone where fatigue is occurring.... It might never fail where the dents are, by the balls ripping through to the end.... instead it might develop a crack inwards from the dents (they are now stress risers).... and rip the whole end off the male fitting.... OR, the inside of the brass female could fail in several ways.... How long will it take to fail?.... A hundred cycles?.... A thousand cycles?.... 10 thousand cycles?.... I have NO idea, but IMO the clock is ticking....
Only use fittings rated for a maximum safe WORKING pressure that is above what you are using....
Bob
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Thanks for posting Bob, and that totally makes sense. I DO NOT want to be on the end of that hose/fitting if it decides to let go. Looks like I need to find a fitting to convert the metric threads on my compressor to 1/8bsp and then I'll just use my Joe B hose which I trust is rated high enough.
Anybody have ideas on what to get?
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I just ordered a male M10 x male 1/8" BSP and a female 1/8" BSP coupling. I'll screw my Joe B micro bore directly into that and do away with the brass foster. Wonder how many are using these brass fosters to pump their guns and tanks up to 4500psi?
Thanks everyone, a little ashamed that I never thought about that fitting being brass :-[
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I have never seen such deep dimples in a male Foster.... That would make me very nervous.... Brass is NOT recommended for high pressures, it is intended for connecting paintball hoses running 850 psi.... Even the steel Foster brand name fittings come in two grades, and only the best one is rated for 4500-5000 psi....
Do you have any idea what material that male QD fitting is made from?....
Bob
I'm guessing brass, I checked and a magnet had no effect on it?
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There is already a thread on the brass versions failing. If steel dimples, brass hasn't a chance. My airventuri probe foster attachment is blackened steel. Not alu. as posted here.
Hey Knife, do you have a link to where someone had a brass fitting fail? Just would like to read it, thanks!
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Tweeter, although I have never seen one, I'm guessing that it is made of aluminum.... The colour of the ridges between the dents where the balls have compressed the male fitting are NOT brass colour, they are grey or dull silver in colour.... While it is true that there are some grades of Stainless Steel that are barely magnetic to non-magnetic (and others that are quite magnetic)…. I have never seen stainless that was so soft as to dent as severely as the one in your photo.... Besides, SS is usually a bright, shiny silver finish because it doesn't oxidize....
BTW, I have looked around a bit for the MSWP of brass female Foster fittings and have found two ratings.... 2,500 psi and 3,000 psi.... I also found some that were rated at only 300 psi, but obviously that was an error, at least I presume so.... In any case, I would NOT use that brass female Foster at 3600 psi, which is what you stated you are filling to.... and with the dents in that male Foster, I would definitely NOT continue to use that either....
Bob
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I had a brass probe that didn't last long at all and it came from my PP700SA pistol which takes 220bar to fill, that probe dented very badly early on and that's when I ordered a stainless one from a vendor in England, that probe cured the problem completely and am still using it with no ill effects. I am almost thinking that it was a very poor grade of brass because the probe that I fill my SPA M16 is brass also but it never dented nearly like the one from the PP700SA did. I still use that same probe too and I also have another just like it that came with my varmint that is still just fine as well. When it comes to quality I think many times the Chinese mfg's aren't really up to snuff when it comes to durability however recently I've been seeing some better quality coming from China, especially with the SPA stuff.
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Bob, the dimpled fitting (male foster) is steel and magnetic. It is an Air Venturi that I bought from PA. When you first said brass I thought you were talking about my female foster shown in the photo. In any case they are both getting scrapped and new parts on the way. Thanks!
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Sorry, I misunderstood.... Yes, the female is brass, I thought you meant the male was non-magnetic.... I'm glad it's at least steel, but must be a soft grade to have such large dents forming.... Point is I would not use either at the 3600 psi fill you need....
Bob
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You're going to get some looseness in any foster fitting when there's no pressure on the line. It's generally nothing to worry about, that's part of what puts the "Q" in QD. If it bothers you there's an o-ring inside the female connection that can be replaced with a slightly thicker one
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Thanks Bob.
Paul, thanks for the post. It wasn't the loose fit that worried me (I've been using it like that for months) it is the dimples that are forming on the male foster. I think the loose fit is what caused it. If the ball bearings in the female QD fit snug inside that groove then I don't think they would have any chance to start digging themselves into the shoulder. I have seen all sorts of posts about these chinese QD fittings and how the sizes are very inconsistent. I would think a part holding back this much pressure should need tight tolerances to be safe?
Not risking it, for $20 I bought some fittings that I can trust.
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Thanks Bob.
Paul, thanks for the post. It wasn't the loose fit that worried me (I've been using it like that for months) it is the dimples that are forming on the male foster. I think the loose fit is what caused it. If the ball bearings in the female QD fit snug inside that groove then I don't think they would have any chance to start digging themselves into the shoulder. I have seen all sorts of posts about these chinese QD fittings and how the sizes are very inconsistent. I would think a part holding back this much pressure should need tight tolerances to be safe?
Not risking it, for $20 I bought some fittings that I can trust.
That's what I get for not expanding the picture to full size. Wow! That male fitting is really taking a beating, I wouldn't use that setup either.
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One failure in particular was with a pump test. The fitting failed and nailed the fellow in the foot. It is on YouTube. Sorry, watch too many to remember which vid.
Joe, B. talks about them also.
Knife
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My Air Venturi fitting is starting to show similar wear as well.
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Peace of mind ;) One fitting is rated 5000psi and the other, 10,000psi (can't remember which is which). Should be good now.
(https://i.imgur.com/BX4Ler5.jpg)
(https://i.imgur.com/z7BocWe.jpg)
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Well, it looks like it happened to someone: https://www.gatewaytoairguns.org/GTA/index.php?topic=148573.new#new (https://www.gatewaytoairguns.org/GTA/index.php?topic=148573.new#new)
A number of things could have gone wrong besides the ball on the shoulder, but the take away is don't be overly confident of the brass and aluminum parts on these foster connectors. And work safe around compressed air! Eye protection and even hearing protection are cheap insurance. (When I fill the mega-blast things, I where ear plugs--I don't need to hurt my ears anymore.)
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I already wear body armor when I fill my guns with this thing, I look like an EOD tech. haha.
Really......I lay on the table next to mine while it's filling my SCUBA tank and take a nap ;D
What Me Worry ;D
I do have to wonder if brass is that weak why are all the male probes I see made with brass?
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By looking at my EDgun probe which is brass, the brass is a heck of a lot thicker than the brass parts on my brass foster fitting. These brass fosters may well be rated for 4500psi but I'm not taking the chance, not for $20. My issue was (I think) the way the two foster fittings fit together loosely causing the dimpling. The fact that it may not be rated for the high pressure was just one more reason to change my setup. YMMV
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I went back and did a second take on your pic(zoomed in) YIKES & WOW now that's a real concern. I have some aluminum dead-ends that I use to check things for leaks and neither one of them show dimples like that. I have some brass foster quick disconnects and so for so good. I only pump to 3300 psi so that maybe why?
Very glad you caught that before you had a failure. GOOD EYE!
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Fill probes have ZERO end load on them because they have O-rings both sides of the pressure port.... Nothing wrong with brass (or aluminum) used properly.... Foster fittings at high pressures does not fit that description....
Bob
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Many thanks on the insight between Foster and Probe Bob.
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Justin
Thanks for the info/photo's,
I have checked all my connectors and have not found anything like your photo showing those dimples,
I only fill to 3000/3200 psi for my tanks etc.
Question for you,
Can you provide the thread size of the components in the top photo, and where you got them,
I can't seen to find the correct sizes needed, and what is that washer called?
I am attempting to attach the Black filter (Yong Heng brand) to my SB F-10 compressor outlet etc.
Tia,
Don
Peace of mind ;) One fitting is rated 5000psi and the other, 10,000psi (can't remember which is which). Should be good now.
(https://i.imgur.com/BX4Ler5.jpg)
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Hey guys check this out. I know its from a different forum but worth seeing for sure! Not sure if it is like mine or not but goes to show that we need to use caution...
https://www.airgunnation.com/topic/close-call-be-careful-with-air/ (https://www.airgunnation.com/topic/close-call-be-careful-with-air/)
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Don, the male/male fitting is M10 x 1 to 1/8" BSP and the female coupling is 1/8" BSP both ends to fit my micro bore hose. That is a 1/8 BSP dowty seal/washer. You can find them on ebay or amazon easy enough. Hope this helps!
https://www.discounthydraulichose.com/Metric_Steel_Hydraulic_Fittings_s/208.htm (https://www.discounthydraulichose.com/Metric_Steel_Hydraulic_Fittings_s/208.htm)
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Having been hose whipped across the face at paintball CO2 pressures using a long hose, I am now a firm believer in good fittings and especially short lines.
Preferably half arm length hoses. I still cringe at the sight of long hoses.
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Hey guys check this out. I know its from a different forum but worth seeing for sure! Not sure if it is like mine or not but goes to show that we need to use caution...
https://www.airgunnation.com/topic/close-call-be-careful-with-air/ (https://www.airgunnation.com/topic/close-call-be-careful-with-air/)
That sounds like happened to DLP in this thread https://www.gatewaytoairguns.org/GTA/index.php?topic=148573.0 (https://www.gatewaytoairguns.org/GTA/index.php?topic=148573.0)..."bearing ring on the female foster fitting blew apart"
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Hey guys check this out. I know its from a different forum but worth seeing for sure! Not sure if it is like mine or not but goes to show that we need to use caution...
https://www.airgunnation.com/topic/close-call-be-careful-with-air/ (https://www.airgunnation.com/topic/close-call-be-careful-with-air/)
The OP in that thread says he’s “Uber careful” but wears a “headset” while filling!?!?
Doesn’t sound like a good idea;)
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Maybe he meant ear protection? I wear ear and eye pro when I is my compressor.
I don't think the Chinese makers and sellers of these compressors care much for our safety as long as we buy their stuff.
Mine came with a VERY lightweight aluminum male foster (probable put in the bag by accident) that I wouldn't trust with 500psi. A seriously light fitting. Ok for me because I just tossed it but what if I was some 13 year old kid trying to fill my paintball tank and end up taking my eyeball out. Just be careful ;)
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Maybe he meant ear protection? I wear ear and eye pro when I is my compressor.
Ahhh, that makes sense, thanks;)
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https://www.youtube.com/watch?v=NirBnWWMdj8 (https://www.youtube.com/watch?v=NirBnWWMdj8)
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Yikes!
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Yikes!
Here's one more appropriate to our equipment--just as scary: https://www.youtube.com/watch?v=tUULhwd4RHw (https://www.youtube.com/watch?v=tUULhwd4RHw)
This guy has a bunch of video like this--he's sell products that protect workers from this sort of accident. Scary stuff out there.
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Thanks for the above videos. The one David posted seems especially relevant to air gunners as we have our body and even our head near the compressor and/or tank at several points during the process of filling a tank or an air gun. Seems that the most dangerous time might be just as highest pressure is reached during filling a 4500 psi tank. The point at which a non-auto shutoff setup requires one to reach in to close the tank valve and to shut off/vent the compressor line, placing one very near the fill whip. This has convinced me to make any new compressor purchase an auto shut off setup simply for possibly a bit of extra safety. You still have to approach it to vent and detach obviously but maybe it will make things a bit safer.
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Just looked at pictures of the AV compressor on PA site. Larger pictures show a brass foster fitting on the charge hose but inset shows a SS foster fitting on charge hose. Something they improved after initial ads?