EEVBlog #1131 - £1M Banksy Artwork Shredded! HOW?

[EEVblog]

A look at how the Banksy artwork "Girl with a Balloon" shredded itself moments after being sold for £1M at a Sotheby's auction.
How long did it sit idle waiting to be triggered?, and was this actually possible?

[Mr. Scram]

Also discussed below.

https://www.eevblog.com/forum/chat/painting-that-shred-itself/

[Bud]

Why is a little rectangular opening on the back plate he was installing? Was it replaced after testing with a solid one 

Also does the shop look something like a paint artist's studio? Looked more of a screen printing shop where they wash screens

[Bud]

The damn thing would weight a ton with a shredder, motors and battery pack. Two people removed it from the wall. Two people. How it could possibly be overlooked its abnormal weight 

[PartialDischarge]

Clearly there was someone in the auction room to activate the thing, what brings my question. I'm not an expert on RF remotes but how long would a commercial receiver live on batteries?

This model https://www.linxtechnologies.com/wp/wp-content/uploads/rxm-fff-lr.pdf takes 5mA, so a big battery would be needed to power it for a few years (as the video says).

[Mr. Scram]

Clearly there was someone in the auction room to activate the thing, what brings my question. I'm not an expert on RF remotes but how long would a commercial receiver live on batteries?

This model https://www.linxtechnologies.com/wp/wp-content/uploads/rxm-fff-lr.pdf takes 5mA, so a big battery would be needed to power it for a few years (as the video says).

It could be a two stage deal, where the device periodically checks whether an activation signal is sent. Primary cells can last a pretty long time too, as was discussed in the other topic.

[PartialDischarge]

It could be a two stage deal, where the device periodically checks whether an activation signal is sent. Primary cells can last a pretty long time too, as was discussed in the other topic.

ok, so if it was done this way then it was a custom made design, maybe someone from eevblog was in on it 

[wilfred]

Why is a little rectangular opening on the back plate he was installing? Was it replaced after testing with a solid one 

Also does the shop look something like a paint artist's studio? Looked more of a screen printing shop where they wash screens

Banksy isn't a paint artist. I heard this was a screen print.

[W9GFO]

I agree that the device was probably built within the last year but I do not believe that there is a real shredder in it. A commercial shredder does not produce cuts like that, the strips are too wide. I think there is a pre-cut canvas and the original canvas. Most likely it can also be reset, which gives purpose to the other motor.

[wilfred]

The damn thing would weight a ton with a shredder, motors and battery pack. Two people removed it from the wall. Two people. How it could possibly be overlooked its abnormal weight 

I think two people were handling it because it weighed a million pounds.

[Mr. Scram]

I agree that the device was probably built within the last year but I do not believe that there is a real shredder in it. A commercial shredder does not produce cuts like that, the strips are too wide. I think there is a pre-cut canvas and the original canvas. Most likely it can also be reset, which gives purpose to the other motor.

If you look at the video he posted himself you see it's a row of exacto style knives. Mysteriously, they do seem to point in the wrong direction.

[Mr. Scram]

The damn thing would weight a ton with a shredder, motors and battery pack. Two people removed it from the wall. Two people. How it could possibly be overlooked its abnormal weight 

You seem to suggest they're not used to unusual art pieces.

[W9GFO]

I agree that the device was probably built within the last year but I do not believe that there is a real shredder in it. A commercial shredder does not produce cuts like that, the strips are too wide. I think there is a pre-cut canvas and the original canvas. Most likely it can also be reset, which gives purpose to the other motor.

If you look at the video he posted himself you see it's a row of exacto style knives. Mysteriously, they do seem to point in the wrong direction.

Yeah, they point in the wrong direction and they are in the wrong location inside the frame in order to get the correct result. Those exacto blades are only there to mislead people from realizing that the original was just rolled up while a pre-cut copy was rolled out.

[Mr. Scram]

Yeah, they point in the wrong direction and they are in the wrong location inside the frame in order to get the correct result. Those exacto blades are only there to mislead people from realizing that the original was just rolled up while a pre-cut copy was rolled out.

Is there any solid evidence that points that way? There is an offset between the plane in which the unshredded piece moves and the plane in which the shreds appear, but it's all a bit circumstantial.

It would demote the thing from a somewhat daring artpiece to fairly mundane media stunt.

[W9GFO]

Is there any solid evidence that points that way?

• The device presented as being what shredded the artwork could not actually shred the artwork - so it is fake. (That much is a certainty.)
• There is a metal box in the correct location to house the required rollers. (True beyond a reasonable doubt.)
• There are additional motors aside from what may be contained in the metal box - likely for unrolling/re-rolling the artwork. (Speculation.)
• The resulting shredded artwork is not consistent with the output of commercially available shredders. (True as far as I know)
• Why show a fake shredding mechanism if there is a real one? To mislead from the real trick, which is that the original is uncut. (The conclusion that I have reached)
• Lastly, shredding the actual artwork (in Sotheby's possession) could present legal problems, but just rolling it up - not so much.

[W9GFO]

...There is an offset between the plane in which the unshredded piece moves and the plane in which the shreds appear, but it's all a bit circumstantial.

I don't believe the offset is evidence either way. The offset is just a result of the necessity of paper needing to be pressed between rollers in order to move it.

It would demote the thing from a somewhat daring artpiece to fairly mundane media stunt.

I agree, well maybe not about the mundane part. Still a good stunt.

[Mr. Scram]

• The device presented as being what shredded the artwork could not actually shred the artwork - so it is fake. (That much is a certainty.)
• There is a metal box in the correct location to house the required rollers. (True beyond a reasonable doubt.)
• There are additional motors aside from what may be contained in the metal box - likely for unrolling/re-rolling the artwork. (Speculation.)
• The resulting shredded artwork is not consistent with the output of commercially available shredders. (True as far as I know)
• Why show a fake shredding mechanism if there is a real one? To mislead from the real trick, which is that the original is uncut. (The conclusion that I have reached)

The conclusion all hinges on the device shown not being a real shredder, but showing something with a bunch of knives people know and can relate to in a video could very well be a little bit of showmanship. Worse things happen for very mundane reasons. Extra motors could also be a sign of wanting to make sure something gets pulled over knives properly.

Without a look at the actual mechanism, it's all conjecture. If I were the new owner, I'd make very sure no one would be able to inspect the mechanism if it really is a rollup type deal. That's assuming it even was a real sale.

[W9GFO]

Without a look at the actual mechanism, it's all conjecture. If I were the new owner, I'd make very sure no one would be able to inspect the mechanism if it really is a rollup type deal. That's assuming it even was a real sale.

Right, and he could always say that the video shown was taken during the design phase and not the final version. Not that I would believe that, but a lot of people would. I think it was a bit lazy on his part to not mount the blades in a plausible manner. If he had done so no one would be questioning if the art actually got shredded.

[Fungus]

I agree that stopping half way down is deliberate. That way the "art" stays intact.

You wouldn't want it all over the floor in pieces.

That's assuming it even was a real sale.

Could easily be fake, which is why it went so high.

OTOH Sotheby's commissions high. 20 percent on the first $100,000 and 12 percent on the rest. It's an expensive prank if the buyer was fake.

[Howardlong]

Very soon after the news, I made a comment on my FB feed that it would be an impressive feat of engineering for it still be working 12 years later: as such, I consider it highly unlikely that this had been sitting like this for 12 years waiting for the right command.

Keep in mind the technology available in 2006. The subsequent video released which indirectly suggests it was shot 12 years ago was in 16:9. Now while it's possible, I struggle to believe that the footage is 12 years old. Put into perspective, in 2006, almost all video was still on tape. The iPhone had yet to be announced. Most non-professional video recording was still 4:3 in standard definition.

If you look at Banksy's bio on Wikipedia, he wasn't selling anywhere near £1m works back in 2006, far from it, he wouldn't have had the resources to create a relatively high quality video.

I'm pretty convinced that while the picture may be an legitimate screen print, the frame was created really quite recently.

My thoughts on whether it really was shredded (as opposed to being wound up in a hidden roll) is that it was shredded. The motion of the top and shredded bottom correlates too well for it to be two separate pieces, in my opinion of course!

Irrespective, the whole debacle is amusing.

[Mr. Scram]

I agree that stopping half way down is deliberate. That way the "art" stays intact.

You wouldn't want it all over the floor in pieces.

That's assuming it even was a real sale.

Could easily be fake, which is why it went so high.

OTOH Sotheby's commissions high. 20 percent on the first $100,000 and 12 percent on the rest. It's an expensive prank if the buyer was fake.

If it buys you this kind of exposure it's an absolute bargain. Even a billion dollars of advertisments won't get you that far.

[Mr. Scram]

Very soon after the news, I made a comment on my FB feed that it would be an impressive feat of engineering for it still be working 12 years later: as such, I consider it highly unlikely that this had been sitting like this for 12 years waiting for the right command.

Keep in mind the technology available in 2006. The subsequent video released which indirectly suggests it was shot 12 years ago was in 16:9. Now while it's possible, I struggle to believe that the footage is 12 years old. Put into perspective, in 2006, almost all video was still on tape. The iPhone had yet to be announced. Most non-professional video recording was still 4:3 in standard definition.

If you look at Banksy's bio on Wikipedia, he wasn't selling anywhere near £1m works back in 2006, far from it, he wouldn't have had the resources to create a relatively high quality video.

I'm pretty convinced that while the picture may be an legitimate screen print, the frame was created really quite recently.

My thoughts on whether it really was shredded (as opposed to being wound up in a hidden roll) is that it was shredded. The motion of the top and shredded bottom correlates too well for it to be two separate pieces, in my opinion of course!

Irrespective, the whole debacle is amusing.

The two pieces being in sync could be easily explained by having the two rollers meshed together with gears.

[Fungus]

The two pieces being in sync could be easily explained by having the two rollers meshed together with gears.

I think it would be more like one of these:



Would you really do it that way? It would explain the fake 'teeth' (they're just for show in the video) and it would make it all more reliable (shredder might fail or cut weirdly, rollers give perfect result every time).

We'll probably never know for sure.

[Bud]

I think any battery would be flat from self discharge and aging after several years, let alone 12 years.
As to the mechanism stopped half way - if it was weak battery , we' d see movement progressively slowing down and not coming to an abrupt stop.
Also the metal box/plate that we speculate might be a commercial shredder has what appear to be machine screws on it. Those are high quality screws not your regular ones. This may be an indication a professional machinist was involved in the build (just a wild guess).

[coppercone2]

you could glue strings along the back of the painting in the middle of the strips. THen you can tie the strings to holes in a dowel. Then you can rotate the dowel so the strings are coiled up and torn away from the painting (say from hot glue or such) as the painting is pulled towards the blades.

This way you could only use one roller and 1 motor with direct drive no gears.

the blades might be sharp enough that the canvas tears on them but I agree it looked kinda strange.

Do people think the painting is rolled up for technical reasons or just because they watched that movie about the art thief?

the mechanism I imagined would probobly work if the blades are sharp enough and it would be extremely cheap and light. The main weight from all this crap comes from the tensioning assembly. If you use detachable strings then you get rid of all of that. It only needs to work once for 30 seconds.

might be as simple as lining strings up on the back of a sheet of paper and pouring wax on it. i don't know if I am explaining myself well. Think of a kite.

I don't think its that crazy because artists are nuts.

The thing in the picture, the cutting assembly, kind of looks like something to psychologically fuck with the person thats inspecting it more then anything, it looks like it was inspired by the SAW films or something..