Sciencemadness Discussion Board

Unconventional Shaped Charges

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infinity - 29-6-2020 at 08:33

Quote: Originally posted by greenlight  
Thankyou..
The next variable to be changed was indeed the flyer thickness up to 2mm.
The projectile from that test did hit in one spot with minimal breakup, the other marks are from previous tests.
Unfortunately it hit on the very top and transferred a third of its energy off the damn plate:mad:



a simple LASER pointer will help you to aim the impact point on target. If feasible you can try out variable thickness to improve penetration. Sof iron will be a good option for coherent projectile as it has better resilience.

greenlight - 6-9-2020 at 21:56

I did have one that I always used to use but the battery went dead that day so I was forced to try and sight it by eye

Brightthermite - 5-10-2020 at 12:02

A .45 jacket soldered into half inch pipe with 4.5 grams of melt cast ETN.

[Edited on 5-10-2020 by Brightthermite]

[Edited on 5-10-2020 by Brightthermite]

IMG_0697.JPG - 2.1MB

[Edited on 5-10-2020 by Brightthermite]

IMG_0695.JPG - 1.6MBIMG_0699.JPG - 3.1MB

dettoo456 - 31-1-2022 at 09:43

Found this new paper on truncated charge shapes. The addition of a thicker plate behind the cone allows for a slower forming (think a subtle push of the cone into its inverse jet) and sharper jet that has better properties than its original counterpart. It acts as sort of an explosive lens-version of a shape charge. Maybe even incorporating the design of a lens into the shape charge might allow for tighter compression and inversion of the cone. https://onlinelibrary.wiley.com/doi/10.1002/prep.202100162

specialactivitieSK - 31-1-2023 at 08:47

https://youtu.be/XtDoPvaCbFQ

Bert - 1-2-2023 at 04:55

Quote: Originally posted by specialactivitieSK  
https://youtu.be/XtDoPvaCbFQ


Very little of what video is coming out of that conflict is exactly what it appears or is described as.

I note in one video segment, someone is just walking along next to the "death ray" and just KEEPS WALKING NORMALY?! I assure you, IRL someone in that position would hit the dirt or go into a higher gear, be it away from kaboom or towards his squad mates smoking remains, not just keep plodding.

From video quality, could be CG animation.

From detail level visible, even if real, could equally likely be Ukrainians getting hit. I've found several videos where Uk propagandists changed titles on some RF drone video of their guys getting whomped and claimed "glorious victory over the evil moskals"! Easy to do when they're carrying same weapons, wearing pretty much the same gear and at least initially were operating very similar vehicles.

Bert - 1-2-2023 at 05:55

Quote: Originally posted by dettoo456  
Found this new paper on truncated charge shapes. The addition of a thicker plate behind the cone allows for a slower forming (think a subtle push of the cone into its inverse jet) and sharper jet that has better properties than its original counterpart. It acts as sort of an explosive lens-version of a shape charge. Maybe even incorporating the design of a lens into the shape charge might allow for tighter compression and inversion of the cone. https://onlinelibrary.wiley.com/doi/10.1002/prep.202100162


Obvious next step is test with a truncated 90° cone primary liner and a proportionally designed disc as secondary liner sitting on top-

A stupid simple bit of machining to accomplish that claimed 70+% increase in depth.

Herr Haber - 1-2-2023 at 08:26

Quote: Originally posted by Bert  
Quote: Originally posted by specialactivitieSK  
https://youtu.be/XtDoPvaCbFQ


Very little of what video is coming out of that conflict is exactly what it appears or is described as.



You are absolutely correct. I belive both the title and the level of the comments below the video have one common cause.

It's posted by The Sun ! My expectancies from tabloids are pretty low ;)

Fantasma4500 - 4-2-2023 at 23:13

one youtuber that oftenly does shaped charges had a video where he had a liner that was made out of copper PLA wire- 3D printed copper cone
90% copper POWDER and 10% PLA plastic
the rolls are iirc 10m/60 euros- spicy.
it doesnt have to be pure metal, the liner displayed very great properties, maybe better than solid copper plate liner even
now, this opens up many possibilities for the amateur community- im a practical man. why bother with 3D printing if this mixture can maybe be heated up and pressed- CAST? low temperature cast??

i came up with these ideas before i got out of bed this sunday:
1. pressed copper powder
2. pressed copper powder with glue or binder
3. CAST copper powder/lowmelting plastic
4. aluminium foil
5. pressed copper wires into cone
6. glass powder/sand

1/2. first up copper powder is very easy, CuCl2 (HCl + Cu - set and forget) + Al (a bit of HCl seems to help this reaction)
or copper salts + ascorbic acid or other reducing agents
one time i managed to make what seemed to be nano copper powder- the colloidal community seems to gatekeep their methods for making colloidal copper because of toxicity- nanopowder is probably unnessecary and would require more binder anyhow
as for binder, i think something as basic as milk could work as it dries up and the proteins in milk gets quite hard, PIB works for RDX in a ratio of about 5% PIB- tar, asphalt, clay, pine resin? a angled steel rod could be covered with aluminium foil for very easy release of a somewhat sticky pressed cone
maybe a cone could be pressed then inserted into a spotwelder, i have seen some small devices made out of tiny little brass bb's that was somehow welded together- possibly pressed and spotwelded, they are used as suppressors for pressurized air systems - a spot welder is easy to fabricate from microwave

3. now.. PLA or maybe even polyethylene could be interesting, hotglue maybe even for a very low melting combination of copper powder and plastic, acrylic doesnt quite melt but rather decomposes if you go much above glass-transition temperature, milk cartons and plastic bags are oftenly made of polyethylene

4. since copper powder/plastic does work- why wouldnt something of similar quality work, aluminium foil? only chance this wouldnt i see is the aluminium oxide which is quite high in quantity since the aluminium foil is thin- and relative to aluminium metal there will be a lot more aluminium oxide than in typical liners- but if this can work we have really wrecked the system in terms of DIY shaped charge liners- having pressed and rammed much aluminium foil into discs for recycling i remember it to reach about 2g/cm3, these discs may then be pressed into cones- or just from start rammed into cones- BBQ / grill aluminium foil is a bit thicker, this may be utilized instead of regular aluminium foil

5. copper wires are found in most cables- selfexplanatory, but might require a lot more pressure - can be done somewhat with wood and a hammer, maybe several tonnes of force and a small diameter would make for some very nice cones? naturally, some cables also contain aluminium- typical super pure aluminium so very soft
https://www.youtube.com/watch?v=oTlD6rvQGbA

6. glass/sand, glass is easy to powder, if that can be used in a kinda binded state it would be very easy to manufacture whatever shape and especially very cheap, although glass seems to be less effective than metal liners

seeing that ETN can be pressed to about 1.2g/cm3- yielding approximately 6250m/s - then theres not much reason to go for fancy stuff, by my opinion increasing VoD shouldnt really make the whole thing much better, too much brisance could maybe crush the liner? i recall nitromethane mixtures being used for shaped charges and they also reach just about 6000m/s

oh- heres the 3D printed liner
https://www.youtube.com/watch?v=BBruJJfs8fI


edit: the video with the death ray is actually an type of anti tank mine that shoots out EFP projectiles, so theyre kinda being hit by anti-armor RPG's or shells, in some of the clips you can see it flying in, this explains the accuracy and why its even an anti armor ammunition fired at personnel

[Edited on 5-2-2023 by Antiswat]

yet another edit: a jackhammer could possibly be used to hammer/press cones- steel rod with 45* tip, then a hole drilled in the back of this to insert jackhammer bit, a bolt with impact driver and a nut could also work to get a very high pressure to press foil or powders with

[Edited on 5-2-2023 by Antiswat]

Microtek - 6-2-2023 at 05:51

I saw that video, and frankly, 48mm penetration from 120g HE is not very impressive. I got 19mm from 1.6g PETN using a handrolled sheet of copper 12mm diameter at the base of the cone. Much easier than working with powders, and more robust as well. I have done some experimenting with pressed copper powder, but didn't get much penetration. Aluminum is not a very good liner for shaped charges, its density is too low (the penetration depth is dependent on the ratio of liner density to target density).
Sintered liners do work, and are used in oil drilling to perforate the well lining to allow the oil to flow out. The reason they use sintered powder in this instance is simply that it doesn't leave a carrot (the solid slug formed from the base of the cone) in the hole, as that would reduce the oil flow.

Herr Haber - 6-2-2023 at 08:03

@Antiswat: Just read through all your points and two things come to mind.
- Find information on the shaped charges used in the oil industry. You'll find some common ideas with what you said. Though I'd be surprised if you dont know all that already :)
- About your fifth point, if you got all this pressure, why not sinter your powder ?

About the video it appears to be a DM22 mine with a tandem shaped charge, not an EFP. Might be wrong though.

Edit: of course it's only after posting that I see Microtek's comments ! Woopsie !
Microtek, it's interesting to compare penetration values given for EFP"s and shaped charges. It's not a surprise that EFP's are worst, but they can be set off from further without disrupting the jet. Every tool its has it's function right ?

[Edited on 6-2-2023 by Herr Haber]

Fantasma4500 - 6-2-2023 at 10:46

Quote: Originally posted by Herr Haber  
@Antiswat: Just read through all your points and two things come to mind.
- Find information on the shaped charges used in the oil industry. You'll find some common ideas with what you said. Though I'd be surprised if you dont know all that already :)
- About your fifth point, if you got all this pressure, why not sinter your powder ?

About the video it appears to be a DM22 mine with a tandem shaped charge, not an EFP. Might be wrong though.

Edit: of course it's only after posting that I see Microtek's comments ! Woopsie !
Microtek, it's interesting to compare penetration values given for EFP"s and shaped charges. It's not a surprise that EFP's are worst, but they can be set off from further without disrupting the jet. Every tool its has it's function right ?

[Edited on 6-2-2023 by Herr Haber]


im looking on google and im not finding much about oil industry shaped charges- seems they just use copper sheet metal cones, .. i mean- they got plenty money?

sinter, wouldnt that require both heat and pressure? my concept is to press it and haveit cure- no need for a gas torch, im sure it also requires many many tonnes, last i looked into it, it was way out of my hands to sinter anything- maybe unless if you use explosives to-.. sinter
can you extrapolate on the things you have found in oil industry's shaped charges? i know shaped charges for rocks are normally aluminium cones as they give plenty penetration

edit: nvm i see microtek already blurted out the oil industry's secret

@microtek 48mm really? didnt they claim it worked even better than their actual copper cone- or at least very close to that? how did you roll that copper up anyhow, .. did it overlap, did you solder it? 1.6g and 19mm sounds very impressive, it must have been quite a sharp cone i imagine? how thick was this liner?

[Edited on 6-2-2023 by Antiswat]

MineMan - 6-2-2023 at 20:52

Quote: Originally posted by Antiswat  
one youtuber that oftenly does shaped charges had a video where he had a liner that was made out of copper PLA wire- 3D printed copper cone
90% copper POWDER and 10% PLA plastic
the rolls are iirc 10m/60 euros- spicy.
it doesnt have to be pure metal, the liner displayed very great properties, maybe better than solid copper plate liner even
now, this opens up many possibilities for the amateur community- im a practical man. why bother with 3D printing if this mixture can maybe be heated up and pressed- CAST? low temperature cast??

i came up with these ideas before i got out of bed this sunday:
1. pressed copper powder
2. pressed copper powder with glue or binder
3. CAST copper powder/lowmelting plastic
4. aluminium foil
5. pressed copper wires into cone
6. glass powder/sand

1/2. first up copper powder is very easy, CuCl2 (HCl + Cu - set and forget) + Al (a bit of HCl seems to help this reaction)
or copper salts + ascorbic acid or other reducing agents
one time i managed to make what seemed to be nano copper powder- the colloidal community seems to gatekeep their methods for making colloidal copper because of toxicity- nanopowder is probably unnessecary and would require more binder anyhow
as for binder, i think something as basic as milk could work as it dries up and the proteins in milk gets quite hard, PIB works for RDX in a ratio of about 5% PIB- tar, asphalt, clay, pine resin? a angled steel rod could be covered with aluminium foil for very easy release of a somewhat sticky pressed cone
maybe a cone could be pressed then inserted into a spotwelder, i have seen some small devices made out of tiny little brass bb's that was somehow welded together- possibly pressed and spotwelded, they are used as suppressors for pressurized air systems - a spot welder is easy to fabricate from microwave

3. now.. PLA or maybe even polyethylene could be interesting, hotglue maybe even for a very low melting combination of copper powder and plastic, acrylic doesnt quite melt but rather decomposes if you go much above glass-transition temperature, milk cartons and plastic bags are oftenly made of polyethylene

4. since copper powder/plastic does work- why wouldnt something of similar quality work, aluminium foil? only chance this wouldnt i see is the aluminium oxide which is quite high in quantity since the aluminium foil is thin- and relative to aluminium metal there will be a lot more aluminium oxide than in typical liners- but if this can work we have really wrecked the system in terms of DIY shaped charge liners- having pressed and rammed much aluminium foil into discs for recycling i remember it to reach about 2g/cm3, these discs may then be pressed into cones- or just from start rammed into cones- BBQ / grill aluminium foil is a bit thicker, this may be utilized instead of regular aluminium foil

5. copper wires are found in most cables- selfexplanatory, but might require a lot more pressure - can be done somewhat with wood and a hammer, maybe several tonnes of force and a small diameter would make for some very nice cones? naturally, some cables also contain aluminium- typical super pure aluminium so very soft
https://www.youtube.com/watch?v=oTlD6rvQGbA

6. glass/sand, glass is easy to powder, if that can be used in a kinda binded state it would be very easy to manufacture whatever shape and especially very cheap, although glass seems to be less effective than metal liners

seeing that ETN can be pressed to about 1.2g/cm3- yielding approximately 6250m/s - then theres not much reason to go for fancy stuff, by my opinion increasing VoD shouldnt really make the whole thing much better, too much brisance could maybe crush the liner? i recall nitromethane mixtures being used for shaped charges and they also reach just about 6000m/s

oh- heres the 3D printed liner
https://www.youtube.com/watch?v=BBruJJfs8fI


edit: the video with the death ray is actually an type of anti tank mine that shoots out EFP projectiles, so theyre kinda being hit by anti-armor RPG's or shells, in some of the clips you can see it flying in, this explains the accuracy and why its even an anti armor ammunition fired at personnel

[Edited on 5-2-2023 by Antiswat]

yet another edit: a jackhammer could possibly be used to hammer/press cones- steel rod with 45* tip, then a hole drilled in the back of this to insert jackhammer bit, a bolt with impact driver and a nut could also work to get a very high pressure to press foil or powders with

[Edited on 5-2-2023 by Antiswat]


I saw that video. It was 80 percent copper powder. They quoted it wrong. It is hard to duplicate the filament. They were wrong, it was not better than solid copper, which should get 6 diameter penetration… they got less than two with the printed ones.

I agree, the 3D printed filament is an interesting idea. I was really excited about it for a while, but couldn’t justify the costs for the filament. I ultimately determined SLA is better for this application than filament. Keep in mind 80 percent copper by weight is only half the density of real copper.

Microtek - 6-2-2023 at 23:30

@ Antiswat: It's possible the printet copper cone worked better than the solid copper one they made, but that just means something about their design was suboptimal. About my rolled up cone, I cut out a circle from a thin (0.2 mm IIRC - it was a long time ago) copper sheet, and made a cut along the radius. Then I used small needle nosed pliers to roll it up to make a double layer all the way round. You can do the same with a piece of paper to illustrate the principle. I didnt solder it, but I might have used some glue between the layers to keep them together. As I said, it was a long time ago and I can't really remember.
A little math and the angle of the cone comes out at 60 degrees (ignoring the thickness of the liner). I wasn't expecting much from the charge, but placed it above a stack of 4 mm mild steel plates to see how many it could penetrate. I think I used abut 1 diameter standoff. Without doubt, some penetration was lost in the small gaps between the plates.
Nevertheless, given that I got less than two diameters of penetration (and as MineMan says, 6-7 diameters is achievable), the only impressive things about my experiment was the small scale since SCs generally perform better at larger scales, and of course that such relatively good performance could be had from a simple rolled up sheet.

@ Herr Haber: Yes, EFPs are certainly both interesting and useful in some situations. I was just commenting on the video about 3d printed copper powder cones.


[Edited on 7-2-2023 by Microtek]

Bert - 7-2-2023 at 12:01

They make a 2.3 mil thick pure copper tape with electrically conductive adhesive, commonly used to line and shield the electronics compartments of electric guitars. I suspect it would lend itself to a multiple layer buildup to a desired thickness- or a single layer might be formed into a cone as a substrate for electoplating to desired thickness without the discontinuity between layers.

MineMan - 7-2-2023 at 13:12

Quote: Originally posted by Bert  
They make a 2.3 mil thick pure copper tape with electrically conductive adhesive, commonly used to line and shield the electronics compartments of electric guitars. I suspect it would lend itself to a multiple layer buildup to a desired thickness- or a single layer might be formed into a cone as a substrate for electoplating to desired thickness without the discontinuity between layers.


Bert! Your a true handyman in this field!

Bert - 7-2-2023 at 16:30

Quote: Originally posted by MineMan  
Quote: Originally posted by Bert  
They make a 2.3 mil thick pure copper tape with electrically conductive adhesive, commonly used to line and shield the electronics compartments of electric guitars. I suspect it would lend itself to a multiple layer buildup to a desired thickness- or a single layer might be formed into a cone as a substrate for electoplating to desired thickness without the discontinuity between layers.


Bert! Your a true handyman in this field!


"If the women don't find you handsome, at least they can find you handy"

https://www.amazon.com/ELK-Copper-Foil-Conductive-Adhesive/d...



813CMYw7CIL._AC_SL1500_.jpg - 281kB

arkoma - 8-2-2023 at 14:06

Quote: Originally posted by Bert  


"If the women don't find you handsome, at least they can find you handy"



I love Red Green. Don't run out of duct tape!

Fantasma4500 - 9-2-2023 at 11:36

Quote: Originally posted by Microtek  
@ Antiswat: It's possible the printet copper cone worked better than the solid copper one they made, but that just means something about their design was suboptimal. About my rolled up cone, I cut out a circle from a thin (0.2 mm IIRC - it was a long time ago) copper sheet, and made a cut along the radius. Then I used small needle nosed pliers to roll it up to make a double layer all the way round. You can do the same with a piece of paper to illustrate the principle. I didnt solder it, but I might have used some glue between the layers to keep them together. As I said, it was a long time ago and I can't really remember.
A little math and the angle of the cone comes out at 60 degrees (ignoring the thickness of the liner). I wasn't expecting much from the charge, but placed it above a stack of 4 mm mild steel plates to see how many it could penetrate. I think I used abut 1 diameter standoff. Without doubt, some penetration was lost in the small gaps between the plates.
Nevertheless, given that I got less than two diameters of penetration (and as MineMan says, 6-7 diameters is achievable), the only impressive things about my experiment was the small scale since SCs generally perform better at larger scales, and of course that such relatively good performance could be had from a simple rolled up sheet.

@ Herr Haber: Yes, EFPs are certainly both interesting and useful in some situations. I was just commenting on the video about 3d printed copper powder cones.


[Edited on 7-2-2023 by Microtek]


aha, thanks a lot for that writeup, very interesting to see these kinda unholy constructions do well- .. this could surely imply aluminium foil would work.
i have managed to come across an old timer toolmaker which happily went into hours long talk about making a cone press die over and under piece and made it with proud perfection to me same day so im stoked to see how easy it will be to press metalplates into cones, a 40mm wide 45 degree incline should make it possible to press at least 30mm wide discs, with some scientific approximates, 37.5mm wide would equal 30mm wide cone- maybe.
copper foil can be had from wish, i suspect foil may crimp a fair bit when pressed, but if it can simply be rolled up an amount of times with still very good penetration thats very promising- and surely worrying to anyone that gets paid to read these forums ..
i have some zinc metal discs to try out as well- seemingly zinc metal shaped charges are a thing, .. one could cast their own zinc metal plate and, well or just press a cone in a tool, adjusting the height the top part comes down, 400ish melting point is fairly doable especially in smaller amounts
https://patents.google.com/patent/WO2000039519A2/en
"At least the capsule consists of an alloy of, by weight, between about 4 and 12 percent copper, 2 and 4 percent aluminum, and the balance zinc and impurities."

Fantasma4500 - 12-2-2023 at 11:19

oh boy.. do i have something to share. to my understanding attempts ive seen every now and then of pressing copper cones .. or producing such, best bets were to electrodeposit copper- im hearing something about cast lead/tin cones- with possibly poor performance, but now it seems that i have with a few tools that was produced on a lathe made copper cones that appear as if they were bought.

so i tested both a 2 tonne hydraulic press with my press frame, and measured it against my homemade handcrank press frame- this device relies on a nut, a 30mm mild steel "C" and a 30mm threaded rod- and of course the cone pressing tool being a 30mm threaded rod attachment that connects with a 30mm nut, and a 10mm mild steel rod at top for manual cranking, this then gets mounted in an also homemade vice- as weak and fragile as 8mm threaded rod on this little vice, simply mounted on wooden table with 8 10mm SCREWS as small as 4mm- very doable sizes.

the hydraulic jack produced cones sure- but the handcrank device surprisingly gave me better results, results that i measured as in how tall this cone would get. on hydraulic press i got to 8.3mm at most, handcrank gave me 8.6! very significant difference
the handcrank is simply 220mm to center of the rod where its mounted through a 10mm hole
the 97% copper plate i used was 21.5mm wide and 1.35mm thickness. after conification it measures 19.25mm wide and 8.6mm tall
theres a slight challenge with having the metal get situated in the middle properly, some help can be had for placing the point center by drawing a dot on the piece of metal before pressing it- and simply pressing plenty until you get a hang of it and/or discarding the ones that didnt go too well

https://i.gyazo.com/thumb/1200/f6121de1d5d1c117f12dc99060d72...

all the joints were chamfered well before welding, the bottom part was left plane so that it could properly contact a vice to keep it in position, alternatively plate with holes in it could be used to attach to a table with screws or bolts to bypass vice- a vice could be taken apart and welded together to shappily manufacture the pressing frame- the spike could maybe be attached directly to the vice jaw with a few welds- as could the lower part very easily and super accurately by pressing the jaws together with both upper and lower parts stuck together

with this construction im willing to sell an amount of these cones that i can now massproduce effortlessly, shipping as far away as australia is about 15 euros- unsure what i would charge for each little cone, 19mm x 1.35x 45* cones is what ill be making for now

Microtek - 14-2-2023 at 09:00

Nice. If you make a couple of dies with successively more severe angles, you can get to a 60 degree cone without problems (just remember to anneal the copper often). I made such a series of dies and matching punches on my CNC milling machine, and have made flawless copper liners with just these tools and a hammer. My only problem is the base of the cone - I would like to find a good way to repeatably machine the base perpendicular to the axis of symmetry. The best I've found so far is to mount the cone on a mandrel that is identical to the final punch, and then cut off the excess on the lathe while using an adapter for the live center to hold the cone onto the mandrel. It works but isn't as convenient as I would like.

Fantasma4500 - 16-2-2023 at 09:43

hammer, copper liners- would it be possible to hammer through copper plate if one was to make a setup that lined up the punch - upper tool, vs the undertool, or maybe sharpened the punch concave? maybe wood underneath to avoid damaging the punch. it seems 1mm copper can be pushed through with just a 16mm BOLT with vaguely fitting hole underneath with about 2 tonnes of force, maybe with just below 2 tonnes if you actually put effort into it. softer metals would require less difference between the upper and lower tool-

i did argue the machinist about making the device more complicated, having it placed exactly in the center, he told me that he could make it so that it would have a little groove where i would fit in a soft metal plate, and then the upper tool would be fixed so that its always centered- my hand crank wiggles about 1 millimeter at the start, but it still works somehow.
we then settled on just making it 40mm wide and no groove- because groove would mean i would be needing more accurate pieces of metal plate, less versatile. with my current press i can go up to 40mm width of plate, groove would limit its versatility

maybe a hand-cranked hole-punch would be the best, a rod moving into a tube, more force = longer / harder handle
this old tony on YT produced a holepunch in which around the upper tool, theres a mechanism with a spring and a washer of some sort- once this goes down and contacts the plate, it keeps the plate from deforming while punching the hole, but also when withdrawing the tool

anyhow heres some pics of my unholy aluminium foil cones, made from a bunch of aluminium foil i rammed in a tube with a rod and a hammer many years ago. i also found it that if you wanna use aluminium foil right off the roll, ideal is not to roll it up and wrap it around itself, you wanna shape it into a ball, and really press it hard by hand, then press this slightly into the die- and then lower in the upper tool- or just pre-shape the al foil discs, they feel very solid, it sounds like metal if you slam it on something of metal, very plausible this will actually work as a liner.
one drawback is that it sticks to the upper tool when the initial foil piece of larger than the tip

https://gyazo.com/0dede25826fcdf24226929b234d9f70f

dettoo456 - 16-2-2023 at 13:49

@Fantasma4500 In theory, by finding the hardness and ductility of each pressing and molding material you can deduce if anything can be made through your method but ofc there are exceptions. Your machinist was right, you should first find the exact radius of your plate to be pressed, cut to exact size (a hole saw and drill press makes that easy and fairly accurate), and center your plate (now a disc) in your concave mold in a sort of edge chamfer so it doesn’t move when being pushed into the mold. Pressing copper with a steel die into a steel or Al mold should be fine.

Fantasma4500 - 17-2-2023 at 05:50

copper is a slight bit harder than ALUMINIUM*- so al mold def not a good idea- besides the softer your mold the more easily it will scratch and deform
i get the drift, perfection is nice- but i have some limits and i dont plan to produce thousands of cones- and then you wanna also consider, how much time would it cost to produce the perfect tool, how much time would that really save you in the end? i think a good start would be to draw a dot in the center of the plate to be pressed
lead has some potential for liner- maybe electroplating copper on a lead cone- or layering copper lead and other similar property materials would make for a better working one? i still wanna try pressing copper powder and glue- biggest issue is making it release smoothly from the mold, aluminium foil to the rescue.

[Edited on 17-2-2023 by Fantasma4500]

Bert - 17-2-2023 at 08:15

If any of you have access to a lathe, or even a large drill press, metal "spinning" of soft copper is an achievable thing. I have made a few shapes this way, even easier, I've modified the shapes of existing commercially "drawn" copper pieces by spinning as well- Realize, while the work piece is normally spun past a tool rest, the TOOL can be spun against a stationary piece as well-

Bert - 17-2-2023 at 08:56

Those who don't learn history are doomed to repeat it!

If anyone new is reading, who haven't been following this thread since the beginning? (Thread has been running 17 + years, now 65 pages long!)

You REALLY would benefit by at least skimming through this huge beast of a thread. Frankly, it OUGHT to get curated and a table of contents created.

NOTE: Click on quoted thread headers "originally posted by" , there are PICTURES you will want to see

For a start:

Electroplated copper cones, user neonpulse presented a workable solution, take a look here:

Quote: Originally posted by NeonPulse  
So i recently decided to try making another electroplated liner. For this process i filled a plastic funnel with car body filler and after it hardened i shaped a tip on the end as it was flat. The angle of the funnel is around 55-57 degrees. The resin form was sanded with some 800 grit sandpaper after this it was then coated with 3 nice even coats with a conductive silver paint. copper wire was threaded through 4 pre drilled holes on the base of the form and it was plated as usual. the coating of copper onto the form was nice and even all around and there was no thin or bare spots. In a previous experiment only one coat of the silver was applied but this produced poor results and a rather slow plating which was uneven in places. I also think the plating bath attacked the coating before a layer of copper was plated to protect it so 3 coats is needed for a faster plating and better coverage all round.The coating goes on very easily and any brush strokes with an artist's brush level out on drying leaving a nice even surface to plate onto. Using this process opens up an avenue to create liners of many sizes and shapes. fluted, trumpet and bi-angled or stepped liners are possible as long as you can form them out of the resin. i guess most materials that can be shaped conically or otherwise can be used (sealing porous surfaces first) and there also is no real limit to the size that can be formed like with cutting metal forms on a lathe. The cone was very easy to remove from the form and the paint stuck to the inside of the liner which is very easily removed with some acetone if it is a problem. The drawbacks are the general cost of a liner as a whole unit, the silver paint is pretty expensive at $10 for a mere 3mls vial but it really does go a long way if used sparingly. throw in the costs of the body filler, copper sulfate, Cu metal, acid and electricity to plate and you have a pretty expensive liner to produce. I haven't any access to a lathe so spinning liners is out for me else i would certainly attempt it. :)



Regarding hammered and/or other techniques in mechanically press formed cones, the good Dr. Liptakov (user name Laboratory of Liptakov) informed us of an easily home made tooling setup and demonstrated a simple anneal/bash/anneal/bash technique beginning from a flattened scrap of common copper water pipe:

Quote: Originally posted by Laboratory of Liptakov  
Needless to invent an aluminum insert. Needless to test copper plating. Needless to produce glass exploding shrapnel. Producing a steel mandrel with an angle of 84 degrees. A 0.55 mm Cu sheet strength. Or 1 mm. Hammer. Wooden chopping block. Steel rectangle. Propane-butane torch. The annealing. Production takes 10 minutes. No lathe. The pictorial compilation hopefully everyone will understand. Loaded: Cyklonan III. 25 grams. Density 1.2 g / cc. Bar diameter 26 mm. Distanc 39 mm. Steel 20 mm.
LL








So. Go "back to the future". No flux capacitor required.


Herr Haber - 17-2-2023 at 11:08

Quote: Originally posted by Fantasma4500  
copper is a slight bit harder than steel


Maybe I didnt understand the context but copper is not harder than steel !

https://www.metalsupermarkets.com/metal-hardness-testing-met...

Microtek - 19-2-2023 at 05:31

Also, though the word 'steel' has been changed to aluminum, that really isn't a problem. The much greater thickness of the mold means that it is the copper plate that deforms rather than the aluminum mold.

Fantasma4500 - 20-2-2023 at 08:48

yes, agree- however with repetitions it will wear down, i tried to press a square brass plate and it carved a slight bit into my mold
maybe with a chamfering and super smooth grinding of the edges of the copper plate aluminium mold could be used- this is mostly just theoretical, unless if someone was to cast it then steel is much more readily available than aluminium, at least where im from. even wood will wear down steel over time

Bert - 20-2-2023 at 10:32

Quote: Originally posted by Fantasma4500  
if someone was to cast it then steel is much more readily available than aluminium, at least where im from. even wood will wear down steel over time


"Casting" steel is not a trivial thing, especially if you want it to be a uniform steel object without faults and having some desired level of hardnes rather than cast iron when you're done. MP for steel would be around 1,300°C, AFAICR.

Brass is way harder than annealed copper, I'd avoid trying to press form most "brass" alloys. Additionally, on annealing brass with 10% zinc, you may well vaporize some zinc if you're not careful.

A lower mp copper alloy which might suit an amateur casting forms for pressing copper with is called "gunmetal":

88% copper
8–10% tin
2–4% zinc 

MP around 1,000°C. Lost wax would be do-able and for small forms, there are jewelry maker type MICROWAVE CRUCIBLES.

Fantasma4500 - 21-2-2023 at 10:47

oh, i meant it as in- steel as in solid steel rod is much more readily available. ive barely seen steel melted in amateur settings done right once- the secret was that he used a decently built air-wood furnace and sealed the steel into clay

copper-aluminium alloy should also be doable, this site claims it melts at 548*C which just makes no sense in my world since aluminium is about 660*C on its own?
https://www.americanelements.com/meltingpoint.html

aluminium wool is very neat for anyone wanting to cast, can be bought cheaply on wish, doesnt take up much heat and takes very high temperature

Microtek - 22-2-2023 at 02:32

I assume you mean alumina wool? I think casting is just about the least convenient way to prepare either the die or the liner itself.
I would prefer deep drawing, spinning, turning or electroforming (or CNC milling) over casting. If you go for turning or milling the liner directly, consider making it from brass instead of pure copper (since brass is MUCH easier to machine than copper in my experience).

Bert - 22-2-2023 at 09:12

Quote: Originally posted by Microtek  
since brass is MUCH easier to machine than copper in my experience


Copper is soft and acts STICKY. Wants to deform rather than cut, chips want to bond to cutting tool edges and screw things up.

In the old days , WHOLE COWS MILK was sometimes used as a machining lubricant for pure copper?! Mostly consisting of water, good cooling properties. The milk fat acted a bit like what we now call "water soluble cutting oils". Bet it discolored the metal though.

[Edited on 2-22-2023 by Bert]

Fantasma4500 - 25-2-2023 at 07:31

this effect is also seen with zinc and aluminium, aluminium has the added issue that its oxide is extremely hard and despite the metal being so soft, drilling and machining aluminium will effectively wear down whatever tool used, even tungsten carbide as both Al2O3 and tungsten carbide is a 9 in mohs hardness
as for lubrication, boiling oil with sulfur can work, i have used bandsaw cutting fluid for spraying while drilling holes and works very well, a suspension of water and sulfurized oil should do for anticorrosion, i have also used a water mix of glycol with some food dye in it, - just for my own sake. sulfurized oils are probably not very good for you can i imagine there could be similar effect as sulfite preservatives upon exposure. cutting fluid surely tastes like engine oil
looking into MSDS i find one claiming cutting fluid being composed of ethanolamine and triethylamine ANYHOW this is well-offtopic by now.

so lets conclude its ideal to have the die made of steel, machined, shouldnt take long to have a die machined manually, just turn the lathe at 45 degrees- or 60 if youre feeling lucky, and cut into a piece of round steel

PLSHY - 30-7-2023 at 21:29

I found a very novel charge structure, the truncated supercharged charge, which can obtain about 15% higher penetration than the ordinary cone, I made it, and plan to start it with 260mlEGDN , if you want to know more data and specific content, you can reply and ask me, if many people pay attention, I will open a separate post

Attachment: trim.90069319-B185-4A8B-B8C1-E82B286AC412.MOV (5.1MB)
This file has been downloaded 195 times

E67C96F4-FC20-4719-AB14-6CEC7A34B058.jpeg - 146kB

PLSHY - 1-8-2023 at 10:47

After thinking about it, I decided to attach a structure diagram and related documents. The truncated material is tungsten plate with a thickness of 5mm. I will start it tomorrow, and I will attach detailed data after it is started.
https://doi.org/10.1016/j.dt.2022.09.017

F6AAC567-5002-424B-8924-9F31C052327C.jpeg - 110kB8A0BDC38-ADAF-4DA1-B968-AA730C16A1A5.jpeg - 3.1MB

Microtek - 2-8-2023 at 08:22

Interesting. How did you produce the liner? Also, that is a lot of EGDN, please be careful of both accidental initiation and all the fragments that such a hefty steel pipe will produce.

Cubane538 - 2-8-2023 at 20:01

Hi guys,
I'm trying to make copper cone by electroforming on lead, it's going to be 32 hours since I started the cell, but it's seems to be not working!!
The layer of copper on lead cone is very thin...
I'm using 5v 700mA Samsung travel adaptor and 400ml copper sulphate solution. 60g copper sulphate dissolved in it. And 15 ml sulphuric acid for better conduction.

I don't know why it's not forming copper layer!!


20230803_073856.jpg - 1.8MB 20230803_073849.jpg - 1.8MB 20230803_073827~2.jpg - 1MB

[Edited on 3-8-2023 by Cubane538]

[Edited on 3-8-2023 by Cubane538]

PLSHY - 2-8-2023 at 20:29

I successfully booted it up yesterday with a 390g EGDN, unfortunately the phone didn't save the video due to the high temperature. I live in the tropic, and yesterday's temperature reached above 35 degrees Celsius. My cover is composed of tungsten plates and copper adapters customized online. Next, I will attach three pictures, which are the appearance of the copper adapters before processing, the damage effect, and detailed parameters. It's a pity that the target I chose was too small, so the jet was missed, but it still caused 10cm of penetration. If there is no miss, I believe that the penetration depth of more than 20cm can be achieved, and I will conduct a second experiment later. The standoff is 10cm, which is 1.8 times the diameter.

EAD47B38-2874-4D7E-9EC2-9C00812D20DF.jpeg - 123kB 334A4ACB-CF97-4C57-80D5-8F2A12549455.jpeg - 132kB D3DFC37A-B442-4D6F-9B63-C5A84EF7C4F4.jpeg - 228kB D2B34AA8-F538-4109-8DD3-8F47FC155AAC.jpeg - 210kB

[Edited on 3-8-2023 by PLSHY]

underground - 3-8-2023 at 02:25

Quote: Originally posted by Cubane538  
Hi guys,
I'm trying to make copper cone by electroforming on lead, it's going to be 32 hours since I started the cell, but it's seems to be not working!!
The layer of copper on lead cone is very thin...
I'm using 5v 700mA Samsung travel adaptor and 400ml copper sulphate solution. 60g copper sulphate dissolved in it. And 15 ml sulphuric acid for better conduction.

I don't know why it's not forming copper layer!!


[Edited on 3-8-2023 by Cubane538]

[Edited on 3-8-2023 by Cubane538]


60g of CuSO4 is too little in my opinion. H2SO4 can not dissolve Cu so the only Cu you are going to plate is from the dissolved CuSO4

Cubane538 - 3-8-2023 at 06:20

Quote: Originally posted by underground  
Quote: Originally posted by Cubane538  
Hi guys,
I'm trying to make copper cone by electroforming on lead, it's going to be 32 hours since I started the cell, but it's seems to be not working!!
The layer of copper on lead cone is very thin...
I'm using 5v 700mA Samsung travel adaptor and 400ml copper sulphate solution. 60g copper sulphate dissolved in it. And 15 ml sulphuric acid for better conduction.

I don't know why it's not forming copper layer!!


[Edited on 3-8-2023 by Cubane538]

[Edited on 3-8-2023 by Cubane538]


60g of CuSO4 is too little in my opinion. H2SO4 can not dissolve Cu so the only Cu you are going to plate is from the dissolved CuSO4


Yes you're right 60 gram is too less!
That's why I added 36 grams more copper sulphate and 10ml of sulphuric acid.
And now it seems to be the copper layer is forming but slowly!!

underground - 3-8-2023 at 06:53

You want the slow forming, the slower the better, also try to use a magnetic stirrer while plating for even better results.

Cubane538 - 3-8-2023 at 08:39

Quote: Originally posted by underground  
You want the slow forming, the slower the better, also try to use a magnetic stirrer while plating for even better results.


What is the best thickness of copper liner for shape charge?

dettoo456 - 7-8-2023 at 15:11

Shaped charge liners between 1.5 to 3mm thick are generally easy to form (machining wise) and perform well for most applications. Anything thicker than that up to around 5mm will do better but they are progressively more expensive and difficult to produce. EFP’s are usually produced with thicker liners.


Cubane538 - 8-8-2023 at 00:38

Quote: Originally posted by dettoo456  
Shaped charge liners between 1.5 to 3mm thick are generally easy to form (machining wise) and perform well for most applications. Anything thicker than that up to around 5mm will do better but they are progressively more expensive and difficult to produce. EFP’s are usually produced with thicker liners.



I'm using electroforming method to make copper liner.
Will the more thick liner will give more penetration?

Microtek - 8-8-2023 at 22:04

The liner thickness should be about 1-1.5% of the diameter at the base of the cone, so the optimal thickness is dependent on how large a charge you are making. It is also dependent on other parameters, but since you are going for a solid copper cone, those other parameters can be ignored.

MineMan - 9-8-2023 at 02:01

Quote: Originally posted by PLSHY  
I successfully booted it up yesterday with a 390g EGDN, unfortunately the phone didn't save the video due to the high temperature. I live in the tropic, and yesterday's temperature reached above 35 degrees Celsius. My cover is composed of tungsten plates and copper adapters customized online. Next, I will attach three pictures, which are the appearance of the copper adapters before processing, the damage effect, and detailed parameters. It's a pity that the target I chose was too small, so the jet was missed, but it still caused 10cm of penetration. If there is no miss, I believe that the penetration depth of more than 20cm can be achieved, and I will conduct a second experiment later. The standoff is 10cm, which is 1.8 times the diameter.



[Edited on 3-8-2023 by PLSHY]


Nice! Looked like some sputtering there, according to the paper a clean entrance hole should be expected. Maybe your cap isn’t lined right. You could also use far less EM. For oil perf charges they use about an ounce of EM for an ounce of liner

PLSHY - 23-9-2023 at 02:57

stamping

A401999D-B3B6-46A8-86CD-C61910423005.jpeg - 133kB

PLSHY - 23-9-2023 at 03:00

stamping

A401999D-B3B6-46A8-86CD-C61910423005.jpeg - 133kB

Microtek - 25-9-2023 at 23:30

Nice cone. How did you stamp it? Deep drawing?

PLSHY - 26-9-2023 at 07:41

Quote: Originally posted by Microtek  
Nice cone. How did you stamp it? Deep drawing?
Yes, four-stage stretch forming, and I also tinned it

AD605BEE-9664-47F0-A856-E8ABDCCF993A.jpeg - 3.1MB

Microtek - 26-9-2023 at 21:58

And some trumpet shaped cones as well I see. How big are they?

PLSHY - 26-9-2023 at 23:06

Quote: Originally posted by Microtek  
And some trumpet shaped cones as well I see. How big are they?
11cm diameter

Microtek - 27-9-2023 at 02:51

I can see why you need such large amounts of HE then. I think you should go for plasticized PETN rather than the ETN/PETN melt we are discussing in the other thread.

PLSHY - 11-10-2023 at 02:50

Electroformed medicine cover, but it produced spiral patterns! Very strange! Can someone tell me how this spiral pattern is produced? Is it caused by the mold rotating too fast? My mold speed is 120 rpm

CD6A359A-C454-4709-A124-E95B26399EA9.jpeg - 1.5MB

Tsjerk - 11-10-2023 at 06:59

Do you have a link to the process you used?

PLSHY - 11-10-2023 at 07:29

Quote: Originally posted by Tsjerk  
Do you have a link to the process you used?
My process is as follows:
Electrolyte: {150 g copper sulfate (anhydrous), 50 g sulfuric acid, 20 mg thiourea}/per liter.
Current density 3A/square decimeter.
The cathode rotation speed is 120 rpm.
The area of ​​the anode is twice that of the cathode.
The distance between anode and cathode is 6cm.
Temperature constant 30 degrees

PLSHY - 18-10-2023 at 02:59

Found the reason! The current density is too high! After electroforming for 24 hours at a current density of 3A, it was removed and the effect was very poor

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[Edited on 18-10-2023 by PLSHY]

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PLSHY - 18-10-2023 at 03:02

Then I lowered the current density and re-electroformed it using a current of 1.5A. This time the effect was much better. You can see the surface and even reached a partially reflective level without polishing. This means that the grains are very So thin!(photo)
Finally, it can be found that there are still some imperfect structures on his surface, so I decided to repeat the electroforming again using a current density of 1A. (In the photo, the medicine-shaped mask has undergone stress relief treatment at 200 degrees Celsius for one hour, so there is some discoloration)

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PLSHY - 21-10-2023 at 06:34

1A

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PLSHY - 1-11-2023 at 07:04

I tried modern electroforming additives again, and the effect was very powerful! It can be completely reflective as soon as it is electroformed!

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Microtek - 2-11-2023 at 01:42

I think the spiraling striations look as if they might reduce performance of the charge. Similar to the known fact that spinning conical liners on a lathe introduces spin to the jet when the charge is fired. This defocuses the jet, and reduces performance.

PLSHY - 2-11-2023 at 04:48

Quote: Originally posted by Microtek  
I think the spiraling striations look as if they might reduce performance of the charge. Similar to the known fact that spinning conical liners on a lathe introduces spin to the jet when the charge is fired. This defocuses the jet, and reduces performance.
It's true that surface swirl patterns can have undesirable consequences, but the spiral arrangement of the internal crystal structure is beneficial. Just like the Spin processing cover is similar to stamping in the static armor breaking state, but it is much higher than stamping in the rotating state. However, considering that I mostly conduct static armor-breaking experiments, I thought about reducing the spiral patterns on the surface as much as possible, or eliminating the spiral patterns through polishing.

[Edited on 2-11-2023 by PLSHY]

Microtek - 2-11-2023 at 23:05

I don't understand what you are trying to say here. What cover are you talking about? What do you mean by "stamping". What do you mean by "static armor breaking state"? Your non-standard terminology is really throwing me off.

PLSHY - 2-11-2023 at 23:37

Quote: Originally posted by Microtek  
I don't understand what you are trying to say here. What cover are you talking about? What do you mean by "stamping". What do you mean by "static armor breaking state"? Your non-standard terminology is really throwing me off.
"Stamping" means the same as "deep drawing" you mentioned before, and they both belong to the same processing method. Static armor piercing is to test the warhead without rotation or initial speed. I'm sorry for my bad English. I'm working hard to learn English

dettoo456 - 6-2-2024 at 12:15

Has anyone looked into the use of wrought iron (or better yet, pure iron) sheet as an EFP or shaped charge liner material? I’ve seen the use of ‘Armco’ Iron (pretty much pure iron) a couple of times and it seems to have very good performance especially compared to copper. https://www.sciencedirect.com/science/article/abs/pii/073474...

Wrought iron should be close enough in terms of C content to the pure iron, as to not drastically affect workability or explosive performance, and it is extremely cheap. The only issue I see is that it is hard to find wrought iron sheet. And almost no one produces pure iron sheet anymore.


underground - 21-3-2024 at 05:07

https://www.youtube.com/watch?v=KMLye177nqo

Laboratory of Liptakov - 21-3-2024 at 10:20

Also you can try normal steel and do it 3x annealing. Heating by PB on red color shining and insert to dry ash on 15 minute. And repeatedly...:cool:

dettoo456 - 22-3-2024 at 07:49

Quote: Originally posted by Laboratory of Liptakov  
Also you can try normal steel and do it 3x annealing. Heating by PB on red color shining and insert to dry ash on 15 minute. And repeatedly...:cool:


Are you referring to using Fe as a liner? After reading around a little bit, I figured that very low carbon steel (commercially sourced) can get close to substituting pure iron if it’s annealed multiple times (>5 times to get best results) in either a vacuum, nitrogen, or just low airflow atmosphere at around 780C for long dwell times - 10hrs or more. Working the hot sheet as well, through rolling or pressing, and then repeating the annealing process will gradually convert the metal to purer Ferrite, which is what the pure iron (Armco) principally is.

Plus, since steel is easy to laser cut, annealed and worked Fe discs could be a very economically friendlier alternative to copper. And the performance of the pure Fe is well-worth the price in my opinion.

Sadly, I don’t have any verifiably very low carbon steel, but I do have a kiln, so I plan to try this process whenever I get time and a sheet off McMaster. I figure that once a steel disc of suitable size is cut, the annealing procedure combined with EFP pressing can just be combined; the deep drawing steps can just be lengthened to also convert the steel to Ferrite. In the end, the finished liner would be exactly as required - both geometrically for the EFP and phase-wise for ductility.

Laboratory of Liptakov - 22-3-2024 at 23:49

I grabbed some old picture for construction EFP with results. Distance between liner and target was 50 cm. Copper liner 1 mm of thickness. Other described.
I mean that was used Liptex as EM.......:cool:

EFP.jpg - 781kB

Cubane538 - 30-3-2024 at 08:30

Hi guys,
I've a question regarding shape charge liner material,
I want to make shape charge liner with pure copper, I was using lost PLA casting method.
i tried to melt the copper in my furnace but it was getting cold very quickly before putting the liq. copper in the mold, The copper didn't melt well anyway.
So I am thinking if I use bronze for making liner instead of pure copper.
will bronze work for shape charge liner??

dettoo456 - 30-3-2024 at 10:45

Bronze will work but much less so, and casting (with copper, bronze, or any other material) will likely require annealing after the fact to produce an actually useful charge - for organized grain orientation in the metal. Tin also will affect ductility, so the resulting jet would travel at faster speeds, have greater elongation, but lower penetration. Its density is also lower, which compounds the aforementioned qualities.

A lead-copper alloy, with <5% lead, might be better simply due to higher density. Lead itself can also be used as a liner but it performs quite poorly. Though, I’d stay away from anything Pb related, simply due to me wanting to keep my precious few IQ points.

Have you tried to just cast Cu discs instead of full liners? The pressing process wouldn’t be too difficult if you already have say 3-5mm thick discs on-hand.

Cubane538 - 30-3-2024 at 11:58

Can I use 80% copper and 20% zinc

[Edited on 30-3-2024 by Cubane538]

PLSHY - 3-4-2024 at 06:35

Quote: Originally posted by Cubane538  
Can I use 80% copper and 20% zinc

[Edited on 30-3-2024 by Cubane538]

No, the boiling point of zinc is too low

PLSHY - 3-4-2024 at 06:42

I tried the electroformed and the penetration reached 17cm. And it penetrated.
https://youtu.be/D57O5nhHSVU?si=hWjNyZZzxerBPPNv

PLSHY - 3-4-2024 at 06:43



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