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Post by Cybermortis on May 28, 2019 18:21:19 GMT
1; It depends on what the windshield is made from, which may not be bullet resistant material if its in 'civilian' use (ie owned by law enforcement, which is likely the case if this was in the USA).
Yes you can kick windshields out from the inside as they are pushed into a recess in the frame from outside the vehicle and held in place by sealant. From what I can tell the MRAP's design is no different here than a civilian car. In the field it seems that they countered the risk of the window being pulled or knocked out from an impact/explosion by adding an outer frame that I'd guess screws into the frame. Police riot vans cover the windows with a cage for the same reason.
2; Actually quite plausible looking at the design.
First MRAP's are known to be top heavy and liable to roll over. So I would imagine that anyone with any real knowledge of the vehicle would be very hesitant to even try a PIT. And if they were willing to try probably wouldn't want to turn the wheel too hard.
Second the MRAP has a central main bumper that only covers the radiator area and doesn't extend to cover the wheels from the front, let along wrap around them. As such I would suspect that attempting a PIT would result in the front wheel impacting and quite possibly riding up onto the other vehicle. If not getting damaged and blowing out.
In both cases I would imagine that an MRAP is quite probably one of the last types of car or truck you'd want to consider using for a PIT. Chances are you'd end up rolling over and sliding down the road.
3; As MB showed in at least two episodes chances are that unless the cable is several inches thick trying to stop a moving car is just going to result in the cable snapping.
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Post by wvengineer on May 29, 2019 0:12:28 GMT
in a commercial trash compactor, you can compromise the hydraulic ram by bracing a swiss army knife (screwdriver blade) in a pipe and wedging it between the ram and the back of the chamber. (it will punch the rivet through the ram and cause a fluid leak.) Plausible, under the right conditions. In theory if you were to slip something in between the cylinder and the outer case, and create a gap between the cylinder and the sealing o-rings, you could create a leak. However: 1. Every high power hydraulic cylinder I've seen has very tight clearances between the cylinder and the case. You only have around 0.010" (0.25mm) between those. I don't see how you could fit a pocket knife blade in between the two. 2. In order to get a blade in between the two, either you have a VERY badly worn cylinder or very poorly made. Either way that introduces more issues. 3. If you were somehow able to get something between the cylinder and the housing, you now have new problems. 3A. When I did a install for a large commercial grade compactor a few years back, it took something like 100 gallons of hydraulic fluid to fill the system. That means you will have a lot of fluid that will need drained before you will start to affect its operation. 3B. Such a hydraulic system operates at 3000 PSI or greater. So not only do you have to force your blade in against such pressure, but if you are able to create a gap in the seal, you will have high pressure fluid shooting out at you. So either it will take a very long time to drain or it possibly will be shooting high pressure fluid, injuring the person making the attempt.
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Post by the light works on May 29, 2019 2:06:58 GMT
1; It depends on what the windshield is made from, which may not be bullet resistant material if its in 'civilian' use (ie owned by law enforcement, which is likely the case if this was in the USA). Yes you can kick windshields out from the inside as they are pushed into a recess in the frame from outside the vehicle and held in place by sealant. From what I can tell the MRAP's design is no different here than a civilian car. In the field it seems that they countered the risk of the window being pulled or knocked out from an impact/explosion by adding an outer frame that I'd guess screws into the frame. Police riot vans cover the windows with a cage for the same reason. 2; Actually quite plausible looking at the design. First MRAP's are known to be top heavy and liable to roll over. So I would imagine that anyone with any real knowledge of the vehicle would be very hesitant to even try a PIT. And if they were willing to try probably wouldn't want to turn the wheel too hard. Second the MRAP has a central main bumper that only covers the radiator area and doesn't extend to cover the wheels from the front, let along wrap around them. As such I would suspect that attempting a PIT would result in the front wheel impacting and quite possibly riding up onto the other vehicle. If not getting damaged and blowing out. In both cases I would imagine that an MRAP is quite probably one of the last types of car or truck you'd want to consider using for a PIT. Chances are you'd end up rolling over and sliding down the road. 3; As MB showed in at least two episodes chances are that unless the cable is several inches thick trying to stop a moving car is just going to result in the cable snapping. 1: I'm actually surprised that they might make a model with standard glass. and from seeing the process for removing a windshield for repair, I'm inclined to question the swift kick, too. 2: yeah, you would have to be a bit careful how you hit it - but in the episode, they tried and failed. the pickup was just too heavy for the MRAP to push around. 3: that was a trick question, I know how easy it is to blow out that eyelet - when you're winching, you always want to get at least 5 wraps on the drum before you put tension on it, or that anchor will blow out - and if you're trying to pull directly on the eyelet, you won't even feel the tug.
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Post by the light works on May 29, 2019 2:09:41 GMT
in a commercial trash compactor, you can compromise the hydraulic ram by bracing a swiss army knife (screwdriver blade) in a pipe and wedging it between the ram and the back of the chamber. (it will punch the rivet through the ram and cause a fluid leak.) Plausible, under the right conditions. In theory if you were to slip something in between the cylinder and the outer case, and create a gap between the cylinder and the sealing o-rings, you could create a leak. However: 1. Every high power hydraulic cylinder I've seen has very tight clearances between the cylinder and the case. You only have around 0.010" (0.25mm) between those. I don't see how you could fit a pocket knife blade in between the two. 2. In order to get a blade in between the two, either you have a VERY badly worn cylinder or very poorly made. Either way that introduces more issues. 3. If you were somehow able to get something between the cylinder and the housing, you now have new problems. 3A. When I did a install for a large commercial grade compactor a few years back, it took something like 100 gallons of hydraulic fluid to fill the system. That means you will have a lot of fluid that will need drained before you will start to affect its operation. 3B. Such a hydraulic system operates at 3000 PSI or greater. So not only do you have to force your blade in against such pressure, but if you are able to create a gap in the seal, you will have high pressure fluid shooting out at you. So either it will take a very long time to drain or it possibly will be shooting high pressure fluid, injuring the person making the attempt. at this point, I am viewing Macgyver as another unintentional comedy. I've forgotten the episode that was in, but it was a "yeah, right" situation.
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Post by the light works on Jun 10, 2019 3:56:45 GMT
the kind of power lines on the giant erector set standards carry 5000 volts. you know. the ones on the left.
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Post by GTCGreg on Jun 10, 2019 15:21:26 GMT
the kind of power lines on the giant erector set standards carry 5000 volts. you know. the ones on the left. Decimal points are so small they really don't matter. Same goes for zero's. Everybody knows they are just there to fill in the gaps. And what's all this "k" business about?
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Post by the light works on Jun 10, 2019 15:57:39 GMT
the kind of power lines on the giant erector set standards carry 5000 volts. you know. the ones on the left. Decimal points are so small they really don't matter. Same goes for zero's. Everybody knows they are just there to fill in the gaps. And what's all this "k" business about? I figured I wouldn't even get into the "if they use a ten foot long insulator chain to keep the line safely away from the structure, what will having a 6 foot tall bag of salt water bridging a portion of that insulator chain result in?"
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Post by the light works on Jun 11, 2019 14:20:36 GMT
an improvised cable cutting device using one of these connected to a solenoid device that works the handles when triggered isn't easy to disable. addendum: oh, and elevator cables are slack enough to climb down, only one cable is used to support the elevator, and if the device above is placed on the elevator cable, it can cut the cable (because elevator cables aren't made of metal) and the elevator will fall taking anyone in it to his death.
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Post by GTCGreg on Jun 11, 2019 15:05:14 GMT
an improvised cable cutting device using one of these connected to a solenoid device that works the handles when triggered isn't easy to disable. addendum: oh, and elevator cables are slack enough to climb down, only one cable is used to support the elevator, and if the device above is placed on the elevator cable, it can cut the cable (because elevator cables aren't made of metal) and the elevator will fall taking anyone in it to his death. Yeah, never saw an elevator suspended by just one cable. Usually there are at least 4 and often many more. And all elevator cables I ever saw were steel, but I do understand that Otis has a new hoist system that uses rubber coated multi-strand belt type cables that look a little like car serpentine belts. And there is no way that thing in the picture you posted would ever cut an elevator cable. If you did have a remote controlled cable cutter, it would have to be either hydrolic or explosive powered. Otis flat belt elevator system (GEN-2)
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Post by the light works on Jun 11, 2019 15:24:33 GMT
an improvised cable cutting device using one of these connected to a solenoid device that works the handles when triggered isn't easy to disable. addendum: oh, and elevator cables are slack enough to climb down, only one cable is used to support the elevator, and if the device above is placed on the elevator cable, it can cut the cable (because elevator cables aren't made of metal) and the elevator will fall taking anyone in it to his death. Yeah, never saw an elevator suspended by just one cable. Usually there are at least 4 and often many more. And all elevator cables I ever saw were steel, but I do understand that Otis has a new hoist system that uses rubber coated multi-strand belt type cables that look a little like car serpentine belts. And there is no way that thing in the picture you posted would ever cut an elevator cable. If you did have a remote controlled cable cutter, it would have to be either hydrolic or explosive powered. Otis flat belt elevator system (GEN-2) add in, that cable cutter has softer jaws than an elevator cable - it is made to cut copper and aluminum. and if you change your mind about cutting a cable, you press the release tab and open the jaws. and then of course, there is the emergency brake that automatically engages if the cable breaks. as for the Gen 2 elevator, a more detailed cartoon implies the counterweight is also on a pulley, so it appears they are both traveling the same distance, but the drive motor is passing more belt across it to reduce load on the drive motor.
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