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In the year 2000, Ben Heckendorn built his first mod.
“Ben: We can rebuild it smaller, better, portable.”
Since then, he has continued his work helping those in need to create new projects. If you’ve got an idea you would like to see built, why not send it to The Ben Heck Show.
“Ben: Hello and welcome back to The Ben Heck Show. If you are anything like me, you probably have piles and piles of pop cans or soda cans, depending on where you live, laying all over your house. What can be done to stop the madness? When will it end?”
“Ben: Well, the human race is in luck because today’s Viewer Challenge comes from the Longhorn Engineer who writes: ‘Hey Ben Heck, this is the Longhorn Engineer - aka Rekarp from your forums. Can you build an awesome automatic can crusher? I’d even come up to help. It could be solenoid powered and even have a readout of how many cans you have crushed.’ Could this end the world’s soda can crisis once and for all? I should contact this guy and see what he is thinking with this solenoid powered idea.”
“Ben: Longhorn Engineer on-screen. So what is this solenoid idea you told me about?”
“Longhorn: Basically you make a big solenoid - like in a pinball machine, and then crush a can.”
“Ben: Can you draw what you’re thinking of?”
“Longhorn: Let’s see. Something like that. So you would have your solenoid right here, it would fire along and hit the can right there.”
“Ben: Oh, okay. Can you tell us the theory behind the solenoid?”
“Longhorn: Basically it’s just a whole bunch of wire that is wrapped around a coil, once you apply current through it and it is drawn through in this rod here that shoots the rod through.”
“Ben: Well okay, why don’t you come on up here to Wisconsin and we will put this thing together.”
“Longhorn: Okay.”
“Ben: See you next Wednesday.”
“Parker: Hey Ben, what’s going on?”
“Ben: Hey, Parker. You made it up from Texas?”
“Parker: Yes I did.”
“Ben: Did you bring your stuff?”
“Parker: The stuff is right here.”
“Ben: Alright, let’s take a look. Ah, looks good. Alright, let’s build this automatic can crusher. Step right in.”
“Parker: Thank you Ben.”
“Ben: Alright, I will just leave that there for now.”
“Ben: Parker, can you explain what you are doing here?”
“Parker: This is our test solenoid set up, that I have been working on for the past couple of weeks. So we have a coil there of wire, we have our bank of capacitors and our rectifier to turn the AC voltage to DC voltage. Basically I want to touch this wire to that wire and this rod is going to shut through and crumple the can. Okay, ready - three, two, one.”
“Ben: Parker, what happened in here - it is like super dark.”
“Parker: Do have breakers, Ben?”
“Ben: Yeah, here they are. Ah, let there be light. Are you sure that is going to work?”
“Parker: It should if you get it hot enough. We have to cool this thing down fast.”
“Ben: Okay for our next test, we have mounted the solenoid into a very high-tech bracket, as you can see. It is similar to how a pinball solenoid is mounted. Parker, prepare for test two.”
“Parker: Test two, so we the solenoid mounted, the can with a hole in it, and the rod set up. So we are going to put this over it to hopefully contain any shrapnel that flies out. Fire!!”
“Ben: Oh, we are getting there.”
“Parker: Much better than the first attempt.”
“Ben: That Pepsi can has seen hard life.”
“Ben: Okay, so we used the test solenoid and it kind of did its job, but it needs to its job better. So now we are going to make a new solenoid that is even longer and more deadly. The gold here is to make the new solenoid the same thickness as the old one, but longer in length. We hope this will give the crushing rod more momentum and power. We will measure the diameter of the old coil and make marks on the new tube so we will know when to stop winding. So, how’s it going over there Parker?”
“Parker: It’s going okay. This is fun, I guess.”
“Ben: By the time we get this finished winding, there will probably a huge size of pop can and it won’t fit and we will be like - nooooo.”
“Parker: Everyone will just have plastic by then.”
“Ben: Here is the old solenoid, it was wound poorly. Here is the new one we just wound while watching Mystery Science Theater 3000. As you remember, we made the marks to figure out how big to wind it but we see before we add more wire - we are going to see if it works with just this much wire. Here we go!”
“Parker: Are you ready?”
“Ben: Yes.”
“Parker: Close your eyes.”
“Ben: Ohhhh!”
“Parker: That sounded good.”
“Ben: Today is day 2, now you remember we made those marks on the coil here to figure out how thick we had to wind it. Now we have wound it all the way - we had to actually link the wire at one point. We are ready for the test to see if we can actually get the plunger to pull in far enough to crush the can.”
“Parker: On, charge, fire!”
“Ben: Alright, let’s take a look. It isn’t crushed that much more. Maybe it is time to think about a mechanical solution.”
“Parker: Yeah I think that is the way to do it now.”
“Ben: Yeah.”
“Parker: It’s just no feasible in terms of how much power it takes and controlling it.”
“Ben: Some things are better left beyond human hands.”
“Parker: Yes.”
“Ben: Now let’s take a break from the Viewer Challenge to work on the X-Box 360 laptop some more. If you have been watching the last few episodes, you know that we are taking an X-Box 360 game console and turning it into portable laptop form. On today’s episode we are going to be routing out the parts to make the case and then putting it together.”
“Ben: Alright, well now we are going to route off the curved lid tops for the X-Box 360 laptops. Actually it is more than a curve, we are going to use this curved bit to do it. See the nice 3/4 inch there? But the problem is, the material is 3/4 inch - the bit is actually longer than that. So see we would be digging into the table past this edge. To solve that problem, we are going to use some cheap sacrificial foam, tape it to the material you want to cut. That way when the bit cuts all the way down, it just eats into the section of foam and the table will be safe.
So as you can see, the bit went down into the blue sacrificial foam giving us a great nice curve. So sometimes it is worth it to waste $2.00 worth of insulation foam in order to cut the material the way you like it. So now I can cut out the inside of those pieces. So we line up three of them on a sheet again, this time we are going to use a 2 x 4 piece of the sacrificial foam. This time we are going to use it as a jig. What we are going to do is, we cut out this shape here inside the jig so we have a place to stick the blank piece. That and when we stick them all in they are held in place by the vacuum and the retention of the foam all around them.
Then we can carve out the insides. Okay, as you can see here - we have grooved all of the walls into one sheet of 2 ft. x 2 ft. Even though splitting the walls into pieces makes it easier to cut more of them, it is still kind of important to place them all on the board. Not only do you have to place them, you have to make sure that you can get a picture of them - we are doing an outline. So as you can see, it should fit.”
The big CNC machine is great for cutting out large things, but for smaller - more intricate parts, it is best to use a laser-cutter or laser-engraver. I used one to do the detailed sections on a unit such of as the ‘ring-of-light’, the buttons and the vent-holes. As you can see, it cuts out pretty nicely and it’s almost like magic. Now comes the lame part, sanding.
“Parker: Playing Bill Paxton is so much fun.”
“Ben: Parker, this game looks awesome but I have some fun stuff for us to do.”
“Parker: More fun than Paxton.”
“Ben: It’s even more fun than this pinball game, come on.”
“Parker: Let’s do it. This isn’t fun at all.”
“Ben: If you keep complaining I am not going to let you white-wash the fence later. So these pieces came off the router and as you can see there, they are not perfect. Even though we used a computer to route these, there is still a lot of hand-labor required to make it look nice. We have most of the pieces ready to go, don’t we?”
“Parker: Yeah, I’m almost done.”
“Ben: Alright - cool, we can start putting it together now. Okay, so now we have the pieces all sanded and it was totally fun, wasn’t it Parker?”
“Parker: Almost as fun as wrapping that solenoid.”
“Ben: So we are going to use the drawings here to piece together the parts of the plastic. Okay, so that is the bottom half of it. We have the thing that holds the screen, it goes right here. Then we have the screen lid. There is a depression here to allow the circuitry on the back of the screen to fit. This part is basically kind of heavy because there is a lot of mass left to it, but that’s alright.”
“Parker: It makes it more sterdier.”
“Ben: Here is the USB access. These holes here, this one is just an extra vent - this one actually allows you to remove the hard drives. That is what that is all about. Then on the back you have the power plug, and this is where the cord comes out for the HDMI connection. If you had the case come apart like this, like this was the bottom and there was a layer up here that came apart - you would need a screw about this long for it to work and it would cost a lot more than these little ½ inch screws. That is why I put the separation down here.
It is a stormy day outside. Now I am going to glue these pieces together, and the big thing is to try and get it as flush as possible. Also, I want to make sure the glue is going to stick so I am going to rough this up a little bit. I love super glue, super glue is so awesome. Sometimes it sticks to flesh really easily. The reason it does is because super glue is activated by water, so when it comes in contact with water - such as the skin which is made of water. That is why it sticks so fast. Alright, now we are going to attach these laser-cut plates to here. See how it goes right there, it lines up and creates the main-face of the unit.”
“Ben: That was fun and don’t worry, my finger survived. In the next episode, we will start putting electronics into the case. We now return to our regular can crushing project.”
“Ben: Okay, we are back. Now we are going to try a mechanical solution to get the cans to crush. As you can see here, I have a little rig going - I have an off the shelf can crusher. I’ve got cord. I’ve got a separate motor, right here and it has a timing belt that goes up to this larger thing here. This will give us a 3:1 reduction or torque. The lever on this, being 11 inches long, gives us even more torque. Okay, now what we are going to do is we are going to run the separate motor a little bit at a time using a micro-controller, like we discussed in the last episode. It will run about 35% a revolution, plug this cord a little bit at a time so we can control it. So we are going to power up this separate motor driver, when I push reset on this micro-processor it is going to start to pull the pulley. Let’s watch it go. There we go. Okay, it was very rough but as you can see we proved a separate motor can crush a can. So now what we have to do is look at this rig and see how we can build the can crusher around it using this theory of operation.”
“Ben: Alright, we are here with math expert Jason Jones.”
“Jason: How’s it going?”
“Ben: He is going to help me figure out this gear ratio thing so we can at least get a theory of operation of how to get the can crusher to work, even if we are not going to have enough time to finish it on this episode. So we’ve got a separate motor there, then we have a larger pulley, and we’ve got the belt. The belt is a lot cheaper than two big gears. So, this one has three times as many teeth as this one. So that gives it a 3:1 reduction. Does that make sense? You are a car guy, you should know about this.”
“Jason: Kind of.”
“Ben: You need to get a stick shift, what is wrong with you?”
“Jason: I don’t know, I am lazy when it comes to driving.”
“Ben: It’s like breathing after a while, you never think about it. So the separate motor drives this, which gives this gearing reduction. Then we have the can crusher over here which is pulled from this position to this position. This distance here is 11 inches. So if that’s the radius, the whole circle of that - if this was a gear, it would be 22. If we had a piston here and a big gear here that was driven by the separate motor, what is this reduction? What does this have to be? If 3:1 is the difference between this and this, but this thing - the diameter of it is basically 2. So wouldn’t that be 11:1?”
“Jason: I see what you are saying., okay.”
“Ben: From this to this?”
“Jason: So it would be 33.”
“Ben: Okay, so we need 33:1.”
“Jason: You confuse me with your Ben-gineering.”
“Ben: A worm-gear.”
“Jason: Awesome.”
“Ben: Yeah.”
“Jason: So how does that work?”
“Ben: You have this and then the worm-gear is up here, which is kind of like this threaded rod that just happens to be on the floor. Picture that, and its driven by a motor here. A one gear has a high reduction ratio, so it is very easy to find one that is like 30:1. So this does 30 revolutions here before this even does one revolution.”
“Jason: Oh, alright.”
“Ben: So what you could do is drive this directly, basically worm-gear here - this turns it and rotates this, this way. So then what you could do is you could make kind of like a piston chamber, like this - kind of like on a locomotive. So this turns and it goes - errt. So when this turns it goes - kapootch, kapootch. Get it?”
“Jason: Yeah.”
“Ben: Crushing the can here.”
“Jason: Oh.”
“Ben: Only I am not sure how fast it would be, it might not be that fast.”
“Jason: But it would be a much smaller size.”
“Ben: Oh yeah, they would be smaller than this even. The ultimate goal is to make something you can fit on the wall.”
“Jason: You redid your basement, what is it 18 inches.”
“Ben: Something like that.”
“Jason: Roughly, yeah.”
“Ben: I just used a stud-finder.”
“Ben: Well, come to think of it - when we did the CNC machine episode - we realized it took about 10 revolutions of the separate motor to drive the machine one inch. So to have a 30:1 worm-gear, we would have to do 30 revolutions to make the worm-gear rotate once. So we would be looking at roughly one can crushed every three seconds, which really wouldn’t be that fast. So now I post it to you the viewers, do you have any good suggestions? Should we try some servo-motors? Do you have any kinds of servo-motors we could try? Can you suggest something? I want to hear from you.”
“Ben: Well, the can crusher didn’t work out quite as well as I had hoped. But at least we got the X-Box 360 laptop case built, and it is coming along. Be sure to tune in next time when we build a portal costume for Halloween. A see-through shirt, woooooooo - based off the hit game. We will see you then.”
The Ben Heck Show is made possible by our sponsors at element 14. For more information on all my projects, and for a list of all the parts I used today - visit element14.com. Visit their community and The Ben Heck Show using the URL below. Join me there to get more details about a chance to win the X-Box 360 laptop we are building. We will see you next time.”