Can I build a hydraulic/etc. press for recyclables on the cheap?

July 8, 2009 4:13 AM

I have gotten into recycling in a serious way, to the point of courting others' contributions and working with an outfit (that pays well enough to pay for the longer trip) some miles away. I would like a press -- hydraulic, Archimedes screw, or something that hasn't occurred to me -- that I could use to compress cans, scrap metal, and various plastics into dense cubes, so that I'd only have to load up the gas-guzzling pickup truck once per redemption trip.

The biggest criterion -- after "strong and tough enough for the job", of course -- is price. Ideally I'd like the saved gas to pay for the press over some amount of time. The figure that rattles around my head is $100-$200. Is this the sort of thing one can build with a trip to a pick-apart lot and a welding torch? I'm hoping the answer to be something like "Take foo, which is a strong five-sided metal cube, and bar, which is an efficient hydraulic jack, and you're there" -- but I'm not a mechanical guy by any stretch of the imagination, and don't know how to fill the variables.

Thanks!

posted by quarantine to home & garden (11 comments total)

Buy a secondhand trash compactor and be done with it.
posted by jon1270 at 4:51 AM on July 8 [1 favorite has favorites]

Nah, trash compactors suck.

I've just stopped running a non-profit based recycling-for-profit endeavor. We looked at this same set of criteria, especially because we were getting 60 cents a pound for cans here and had ~40 bags a week of them coming in. (Btw 27 cans is 1lb.)

Anyway---there are some ghetto options. The first one, which I'm pretty sure came from an AskMe I posted some time ago, was that we made a wheel jig for our big truck. Effectively it was an almost-open-bottom trough, into which we poured cans, placed the trough behind the wheels of our big-ass-box-truck, and then ran over them. Add more cans, repeat. Could totally be done with a regular truck, just less volume at a time. You get about 6 or 8 to 1 this way. When it was done, we'd lift it up, the cans would fall out the open bottom (or rather stay on the ground), and we'd use a snow shovel to re-bag.

There's also a video on youtube of a kid pedaling a bike frame where two 55gallon drums full of water rotate in opposition about half an inch apart...the cans are dumped in the top and they smoosh on the way through. Seemed like a lot to engineer.

So the last option, which is KICKASS but NOT $200, was that we bought a briquetter, which is effectively a very small baler. I wrote a grant to do it. FYI, MOST states have excellent grant programs for diverting solid waste, you might check with your local solid waste authority. The one we bought cost us like $1600 shipped. HOWEVER, it makes your choice of 18"x18" or 24"x24" cubes of cans/plastic/cardboard. Be advised that a 24" cube is very, very, very heavy and takes a lot, lot, lot of cans. Your crush ratio is about 12 or 15 to one this way. BUT, recycling yards love them baled and prepped, and you can add cardboard, office paper, and plastic to your repertoire. Depending on where you are, pulp mills pay FAT CASH for paper stock to recycle.

(The document destruction guys usually make more from recycling than their secure destruction contracts.) I know this because, until they sold their company, I had a contract for one to supply biodiesel.

Anyway...try the trough thing. Scrap lumber and all. Obviously be aware of your nails or screws, and always remember that people don't sort what they give you very well. We got glass bottles, tin cans, vienna sausage tins...cat food tins...that sort of stuff all the time in our aluminum.

I'm pretty passionate about this field. I very much feel that us not getting paid to give someone else free money is the reason that recycling has not, as a general rule, taken off in this country.
posted by TomMelee at 5:13 AM on July 8 [10 favorites has favorites]

Oops follow-up. Trash compactors don't work for this purpose because they don't like cans. First, the cycle is tooooo slow. Second, they jam in the container. Third, the compaction rate isn't good enough, and fourth, they work on the principle that each additional load adds to the compaction. So...you add 10 cans, smoosh. Add 10 cans, smoosh. Repeat about 6 times and you've got a small trashcan jammed of partially smooshed, sharp as hell cans that won't come out.
posted by TomMelee at 5:15 AM on July 8

You might get some ideas from plans for fruit presses and cider presses .
posted by exogenous at 6:04 AM on July 8

Many, many years ago as a Boy Scout, I helped staff my home town's recycling center. They had a home grown solution that was low-tech and cheap. It was a large iron flange and a metal fence post, not unlike this or this. You lift it up and drop it on the cans. It flattens them quite handily. Watch your toes.

We smashed cans and filled up 55 gallon drums with the flattened chips. It took two adults to move a full can, so if I were you, I'd put your container in your truck and then load the container, not the other way around - unless you have a winch.
posted by plinth at 6:26 AM on July 8

A shop press would be a good place to start. All you'd need to build is a die which could be as simple as a three pieces of steel plate and a short piece of large diameter pipe, maybe 10-12" across and the same high. Cut two pieces of the plate to fit inside the pipe. Weld one of them to the third piece which should be larger than the pipe. Place the welded piece circle side up on the bed of the press; place pipe over the circle; insert cans to fill; place top piece on and compress. An air over hydraulic press would speed the compacting part up but will kill your budget, especially if you don't already have a good compressor.
posted by Mitheral at 7:58 AM on July 8

Could you just crush the cans down individually, as they're thrown away? That's what we do; we have a recycling container that has a "can crusher" mounted on top of it, and you just crush the can and then it slides into the bin. Very satisfying. You can fit 4 or 5x as many cans per bag when they're crushed like this, I'd guess.

Replacing every can bin in your pickup area with one of these seems like it would be cheaper than buying a legitimate bailing machine.

Alternately, if you can't get a crusher for cheap, maybe a shredder would be easier? Aluminum beverage cans are quite soft; you couldn't run them through an office/paper shredder, but it wouldn't be that tough to shred them. The redemption machines in most stores do this, I think. (Or maybe they shred the plastic. Might vary by machine.)
posted by Kadin2048 at 8:03 AM on July 8

Just my 2 cents again. "People" (with a capital P, not any of us MeFites) don't recycle for a lot of reasons. They don't recycle because it doesn't pay, because it requires "work" (you want me to crush my OWN can? But I wear heels! or My arms aren't strong enough or Ugh don't you do that yourself, I AM giving you my cans!), and because it's "dirty."

Unless you're only recycling from a circle of close friends, do NOT expect that your participants will pre-crush for you.

I managed to get a couple frats and individuals to do it on the basis that it was "fun when drunk" or "you can save garbage bags by fitting more in there", but by and large...no. I mean, people aren't even bothered to empty out the last dregs of soda half the time.

In my experience. Maybe everyone here is a weiner. my town not MeFi nobody here is a weiner. ya rite.
posted by TomMelee at 8:27 AM on July 8

I think a little (and I do mean a little) bit of welding and a hydraulic log splitter would kick the shit out of this job.

If you wanted to put more manual calories into it (and maybe pay a little less) I can image outfitting a high jack or bottle jack to do this job as well.

Or hell, a motorcycle/ATV lift . . .

There are TONS of options here, and all of them are open to you depending on your craftiness and your budget.
posted by milqman at 9:58 AM on July 8

Quarantine, you're my hero. You need a Superhero name.
posted by wherever, whatever at 11:36 PM on July 9

Leave it to MetaFilter to have the first responder be someone who wrote a grant request for the problem at hand. Sheesh. Thank you.

As for a Superhero name, in these post-Code days, wouldn't "Quarantine" be acceptable? ;-)
posted by quarantine at 3:50 PM on July 12