Factual error: We see Hoffman has to use pliers and force to remove Strahm's hand from the grill. However, since the hand is freshly severed, rigor mortis would not have set in, and he should have been able to remove it with ease. (01:09:30)
Continuity mistake: Jill opens the 6th envelope to show Hoffman. When she does, the envelope instantly vanishes from her hands. (01:18:25)
Continuity mistake: When Hoffman wants the envelopes, Jill's collar is turned up. Camera changes and it's lying flat. (00:20:25)
Revealing mistake: When William is running at the end, there is already a blood trail on the floor. Clearly from another take. (01:15:10)
Continuity mistake: When William sees the way forward, he puts his hand on the glass. There is no blood on the glass from the previous shot, and in the next shot, when he tells Addy to be careful, the blood is back. (00:39:20)
Revealing mistake: When Eddie is cutting the stomach flesh, there is a point where if you look carefully, you can see the outline of the fake flesh. (00:03:50)
Continuity mistake: The amount of Petrol that Hoffman chucks over the FBI lab, Perez, and his boss, is more than what could be in the single container we are shown. (01:09:00)
Continuity mistake: When Simone has a go at Hoffman in the hospital, someone puts their hand on her shoulder. Camera cuts and the hand has gone. (00:16:00)
Continuity mistake: When Erickson is offering full disclosure to Hoffman, Erickson's badge is uncovered. Camera changes and now it's half under his jacket. (00:14:20)
Continuity mistake: When we see Eddie cutting the flesh in the opening game, the amount of blood on his shirt decreases and increases between shots. (00:04:40)
Continuity mistake: At the start when Simone is telling Eddie to wake up he has his hand on his chest. Camera changes and it's not. (00:01:50)
Continuity mistake: When Hoffman says to Amanda "Are you sure about that?" his mouth is right next to her ear. Camera cuts and it's a lot further away. (00:44:10)
Visible crew/equipment: Just as we see the flashback with Amanda, Jill looks at where Amanda stood, then turns to where John was stood and sighs. As she does, a boom shadow is seen to move across her hair. (00:23:15)
Continuity mistake: When Hoffman leaves the hospital room, the male doctor has his hand on Simone. Camera changes and now he is gesturing with it behind her. (00:17:10)
Continuity mistake: When talking to Pamela near the start, her notebook is open or closed depending on the angle. (00:15:05)
Continuity mistake: When Simone is cutting her arm off, the amount of blood on the table differs between shots. (00:04:40)
Continuity mistake: When Eddie puts the first bit of flesh through the fence, he has his face leaning on the fence. Camera cuts and now it's not. (00:04:20)
Continuity mistake: At the start, Simone puts the rubber tube round her arm. Camera cuts - it's no longer round her arm and she puts it round again. (00:03:35)
Continuity mistake: When Hoffman talks to Pamela, he turn round and leans against the door. Camera changes, and he does the same action again. (00:14:35)
Continuity mistake: We are shown a clip at the end of someone putting the reverse bear trap on Amanda in Saw. However, the device is not the same one as seen in Saw. Note the mouth section. It is a lot thinner than in Saw. (01:17:50)
Answer: The tools were chained to the tables, and there wasn't anything else they could've thrown down onto the scales.
erikvduyn