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MythBusters: Salsa Escape

summary in the extended

Cleaning cement from a cement truck with dynamite

There were two variations of the myth being tested. The first was that you could use dynamite to clean out the inside of a cement truck. Cement accumulates inside of the barrel and is usually removed by manual labor.

The second variation is that a full load of cement hardens inside of the truck, and is similarly removed.

The MythBusters crew managed to get a free cement truck that was on its last legs. They messed up during the setup and accidentally overloaded the truck and left it half full of cement (aka "a floor"), but Adam didn't mind because it would allow them to try and bust both myths simultaneously.

Experiments:

Cherry bomb: 'poof'

More illegal fireworks: 'poof' (the MythBusters crew is very bored at this point)

1 pound black powder: a reasonable boom that took off some of the slag holding onto the wall, but nothing off of the floor.

At this point a second cement truck arrived, this one properly setup to not have a floor of concrete in it. They decide to use up the rest of their materials testing the myth and loaded it up with a stick and a half of dynamite's worth of material.

Stick and a half of dynamite: At first it appeared that the cement remained intact. Scottie went inside and discovered that a lot of it was broken and that the remainder was coming off fairly easily.

Myth 1: cleaning cement coating off of barrel using dynamite: plausible

The MythBusters crew, for no apparent reasoon other than entertainment decide that in order to test the other myth (getting the hardened floor of concrete out), they are going to simply blow the entire truck to smithereens in their biggest explosion to date.

They went out to a Calaveras County quarry, shut down a nearby highway, and with the help of retired FBI agent Frank Doyle loaded up the truck with 850lbs of commercial blasting agent. Doyle: "anticipate we will take this truck down to the frame rails."

For the appearance of safety, they made a 1 mile exclusion zone around truck because of high velocity frag steel shooting off, though the photographer is stationed on a hill just above the truck, because he is apparently expendable.

850lbs of commercial grade explosives: very satisfying explosion, leaving very little left of the truck, though surprisingly at least one of the tires in unpunctured.

As for the mythbusting, Jamie: "This has got nothing to do with the myth. this is just a big boom."

There is no concrete.

There is no truck.

Salsa escape

According to the myth, in 1996, Juan Lopez escaped from his Mexican cell by dissolving the bars using salsa from his jailhouse dinners. It took six years to dissolve the bars, and he's never been seen since.

This mythbusting was setup as a Adam-and-Jamie competition to see who escapes first.

The build team built a faux cellblock wall with several windows, each holding 5 different metal bars:

• hot roll
• cold roll
• galvanized
• stainless
• wrought iron

Adam and Jamie studied six different types of salsa to identify the key ingredients in dissolving the bars. Mildest salsa (canned salsa) was the most acidic and also had the highest salinity, so it was chosen for the experiment.

• canned salsa
• salsa verde
• acid control
• saline control
• Adam's bar
• Jamie's bar

Adam started off using electricity to speed up process in the hopes of kicking off electrolysis. The electricity did a pretty good job of scorching the salsa.

Jamie, due to "good behavior," acquired a radio, which Jamie will also use to add current to the salsa. However, the radio provides DC current. Adam is using AC current, which Jamie says will not work as quickly for electrolysis.

It quickly becomes apparent that Jamie is beating Adam -- his bars are pitting while Adam's are not. After a month, Jamie is about halfway through his bars, whereas there was no discernable progress on Adam's bar.

Adam gives up on his approach and instead goes for the "Alcatraz" approach using a vacuum cleaner motor and drill bit (pilfering from the machineshop, of course). The drill immediately flew off the motor, which ended that attempt.

Adam then went for the Jackie Chan Shanghai Noon approach, which involves peeing on a piece of silk, wrapping it around the bars, and then tightening it by twisting with a stick. The shirt broke, bars were fine, and there was urine everywhere.

After four months, there was only a tiny sliver of Jamie's bar left. They examined the results of the other bars. The salsa beat the controls (separate acid and saline mixtures), which seems to indicate that it is a combination of the two, or other chemicals, that works best. The salsa managed to take out .008" of iron in 110 days.

plausible