Saturday, February 9, 2019

First HDPE Shredding- Sled Shred!

People love to drive to Flagstaff, buy cheap sleds from Target, let their kids break the sleds in the forest, then abandon their trash in the snow. I have partnered with a local gear shop called Snow Mountain River (SMR) to recycle them into something marketable.

Today I went to grab the first batch of sleds, 50 lbs of green Paricon Model 648's originally purchased at Walmart or Target for about $10 each. Only one of all those sleds in all the colors had a recycling logo. I contacted the company on Facebook and they were not especially helpful, saying the sleds were "either" HDPE or PP. Hah. Since the one is labeled HDPE and they are all the same model I'm going to ASSUME they're all the same.

The idea was to take them home, slice them down to shredder size, and see how well they shred.

I recently got this antique Shopmaster band saw in Phoenix for this express purpose. I figure if it's been running 50 years it'll run another 50 years. Even with the dull blade it cuts through plastic quickly, but for woodworking I'll need to buy a sharp blade. Next to the saw is the stack of broken sleds.

I ended up with one large Rubbermaid bin and three 5-gal buckets full of these scraps. They were all overflowing. I blew the shredder out with the air compressor and shoved some sleds in.

Success! They don't jam as bad as the polypropylene. Overall not bad.

Ended up with about 4 gallons, I think, after about four hours. Lovely! I'll have a few of these buckets before I'm done.

I will be demonstrating the shredder at SMR in Flagstaff on Wednesday! 2-5pm. If you're in Flag feel free to stop by. I might do another demonstration for them later too, if there is much interest in the project.

Shredder is operational

I finally got some retainer clips that fit the gearbox shaft (thank you McMaster Carr) so the shredder is working again!

Of course I promptly jammed the thing with some polypropylene. This jam was the worst yet. I pulled the mesh out of the bottom, chiseled at the jumbled up plastic, tried to pull it out by installing a screw and yanking it with a vice grip. Nothing.

So I decided to go with the nuclear option: partially disassembling the shredder. I pulled the bolts out of the spacers on the cutting side. The plastic was bunched up between the blade and the spacers.

With the spacers freed I was able to knock #4 down to let the plastic out. Then I straightened them out again and replaced the bolt. Good as new, but what a pain the butt.

Friday, January 25, 2019

Shredder Updates

The coupler and shaft have been a big sticking point. I still haven't been able to locate clips to keep that shaft in place, but will be seeking some out ASAP. Currently the shaft works its way away from the shredder, to the point that it put pressure on the elastomer "spider" middle piece.

Squidgy spidey. I'll be getting a replacement. I don't think the metal parts have touched yet, but they will if I don't fix it.

Real quickly I'll go over another broken product I've been given. This was an old humidifier. I pulled it apart and unfortunately could not use ANY plastic from it!

They're all marked #7 "OTHER". Is it ABS? PC? PA6? No idea, and I'm not going to do a melt test just to figure it out. Bad design. What annoys me the most is that any of those plastic type abbreviations would have taken less effort to enter onto the part than "OTHER". At worst it would have take two fewer letters!

I ended up throwing the wiring, metal, and motor into my e-waste pile for recycling, so it's not all being landfilled.

Short video of the shredder and my bucket of polypropylene!

Friday, January 18, 2019

Shredder and Motor Walkaround

And after that, I started shredding. Unfortunately I forgot to put keys in the coupler so that messed it up a bit. I took the shredder to the machine shop to get a key made, and brought the motor's key home to install. Ugh.

Tuesday, January 15, 2019

Motor works!

I've learned a lot from this project, and with the help of Ward got it all hooked up and running. The motor does pull a lot of current, but I'm hoping it will not have issues once load is put on it.

I also got a Lovejoy Coupler machined to fit the gearbox and the shredder. It has that black rubber part between the two halves, and allows the shafts to be slightly misaligned without causing bearing issues.

I took them all home and mocked them up on the table! Next is making a spacer to keep the shredder at the right height, then mounting everything up, cutting a hole in the table for plastic flakes, and mounting the controller.

More Deconstruction & Product Critiques

I have been collecting ever more broken products to recycle. Since we didn't get but one bike at the Fix-It Clinic this past weekend I ended up taking apart a Dyson vacuum there. Below I'll detail that and some of the other items I've been pulling apart. Some have been great, some have been horrible. Some have helped me learn how to efficiently disassemble products.

First up, the Dyson. I didn't get photos of this one during disassembly, but partial disassembly took approximately 2 to 3 hours. All the fasteners were hidden, and half of them were just plastic clips. This made it immensely difficult to just get the thing apart. And even when it was apart I found that the big yellow ball was a two-shot mold, which means one material was injected directly into the other, making them inextricable.

Additionally, one large portion of the main frame was created with two different types of plastic glued together. not usable. Actually, none of the yellow plastic was labeled for recycling either. Horrible.

The Eureka Maxima vacuum offered me a few parts including the red ABS head, but I didn't get to take that one apart. I believe the unknown black vacuum was the one that had a WOODEN brush roll. High five for natural materials!

The LG Model LUV300B vacuum was a treat to work on. Every bolt was easily accessible and changing a belt or even the broken motor would have been a 15 minute job. Unfortunately I got it partially disassembled, so I finished the job.

 You can see the brush motor here, held in by two or three bolts. The head cover was extremely easy to take off. There were very few plastic clips; almost everything was bolted in with Phillips head screws. The motors were large compared to the other vacuums I've taken apart. A well-made unit for sure, and probably easy to fix. Almost all the plastic pieces were marked for recycling, most being ABS or PP.

The HP Photosmart C5200 Printer lent a good amount of usable High-Impact Polystyrene (HIPS), some ABS, a little metal, and not much else. I will have to find a way to get rid of a few circuit boards from it too, of course.

This one started out looking promising. The entire outer shell was made of usable thermoplastics. I pulled the glass out of the scanner to hopefully use in a custom picture frame later- the third I've collected so far. But once I got into the printer things got grim.

The printer was very well-built with lots of metal, but part of the high build quality was also due to HP's liberal use of glass-reinforced ABS and polycarbonate (PC). Everything inside seemed to be made of the stuff, which is not recyclable as far as I'm concerned. Maybe someone could do it, but I'm not going to attempt it.

A few pieces were usable though. Here we have some POM rollers held by steel screws and unrecyclable roller carriers. The whole grey piece there is ABS as well. Below is a photo of all the larger usable pieces along with a small sample of the stuff I can't deal with, in red. I've gotten into a habit of marking things with a Sharpie to keep them straight.

Is it better to have a longer-lasting product which is less recyclable, or a more disposable product which has a higher percentage of its parts made of easily recycled stuff? I feel as if there may be a middle ground at the expense of size and weight.

Next is one product that someone from Facebook dropped off. I've gone through several vacuums from FB so far, but this the most annoying. It's a Shark brand vac. Everything is put together with either security torx screws, glue, or some form of two-shot molding. Several parts had paint or chrome plating which needs to be removed before recycling. Some parts were not labeled for recycling.

Below is the top of the canister, disassembled. You can see that out of six parts in this assembly, only three are directly recyclable as-is. I could try to strip the chrome off with oven cleaner as diecast car customizers do, but it's probably not worth the tiny piece of ABS.

Next, the canister itself. Only a small fraction of the material is actually usable.

Close-up of the screen. This had to be removed from the canister by use of a steel punch, a long piece of scrap metal, and a hammer. Anyway, the plastic was molded around the steel screen, making this piece unusable.

Here's the vacuum head with its GLUED-ON lighting windows.

No, you can't peel them off.

Wire cutter time.

Last was a Panasonic cordless land line phone from a Facebook person. I think I got more usable plastic parts off this little thing than I did the entire Dyson vacuum.

This glue might not come off without some work, though. Unfortunately construction like this greatly limits the item's disposal options.

Here is the e-waste. Quite a lot for such a small product.

 That's all the deconstruction I have for now. Stay tuned!

Saturday, December 29, 2018

Deconstructing Waste Objects & Identifying Scrap Plastics

Above: all the gears from a single Epson printer-scanner-copier. Most unmarked, but probably polyoxymethylene (POM).

While the shredder and oven work is halted I decided to keep myself busy for a couple days by disassembling some machines from the trash. At hand were an Epson printer-scanner-copier probably purchased at Target less than five years ago and a Bissel vacuum which looked about 15 years old.

With three screwdrivers and a little TV I ripped apart these two objects which people in my development had thrown out this year. I noticed that most parts were labeled for recycling, but some oddly weren't. Here are some examples of ABS plastics I got out of the pile, and photos of the identifying markings.

First up and one of the largest pieces off the vacuum was this blue brush cover. The complex stiffening ribs underneath make it hard to find information, but stuffed into one of the holes is the marker "ABS".


Next, a part of the printer. This used to hold long, thin rollers, probably to move paper. The marking here is quite obvious, and helpfully uses greater than and less than symbols to denote the plastic type. This specific one is marked >ABS KD15<. I do know that it's ABS, but the KD15 is a puzzle. I've Googled it but found no relevant results. It's probably ABS with an additive, and that additive probably isn't a toxic Brominated Flame Retardant (BFR). It may be something else toxic, but I can't find an MSDS so really have no clue.

Another smaller piece is natural colored ABS. The type is small but legible.

The printer actually had three different colors of ABS, this one being grey. I wonder why the material marker is so small when there are obviously quite large areas to potentially locate it. At about 11" (28 cm) long, there's enough real estate.

Next up was the Bissel's dust collector. This consisted of several pieces stacked on top of each other. Some pieces were ABS, like this one.

Others were polypropylene. The bottom piece, though, is a mystery. It certainly appears to be made of the same material as the one above.

But markings are elusive. I would assume it's ABS just like the other, but I can't afford to contaminate a bucket of ABS if it isn't.

  This is why it's important to mark every piece, especially pieces this large. If and when take-apart culture is more widespread, these markings will be the difference between something being turned into something else, and being sent to the landfill.


I encountered multiple plastic types as well. Here is a short list of them:

PC- Polycarbonate, I assume. Scanner light housing. The only piece of PC in the entire product. Didn't collect enough to be worth recycling it.

PP-FR- Polypropylene- Fire Resistant. Printer power supply box. Likely toxic. Trash.

PP-ND- Polypropylene ??. No idea what this means, and I don't remember what it was on.

PS-HI (aka HIPS)- Polystyrene- High Impact. Most larger printer parts. A combination of brittle PS and durable polybutadiene rubberizer, it's apparently used for many consumer products. I did find an MSDS for this and it is not listed as a possible or probable human carcinogen. Good news. I'm excited to see if this will work well for my shredder.

POM- Polyoxymethylene. Natural colored gears and small parts in printer. This was a mystery to me until I looked it up. It's a high-precision, low friction plastic with good dimensional stability. I believe that means it doesn't heat and shrink much. Most gears are not marked >POM<, but just like soda bottle caps it's just about a foregone conclusion so I'm going to go with it. I'm also excited to experiment with this one but will need many more gears to be able to make anything.

So far that's it for the deconstruction. I sent out a couple calls for plastic and machine donations. A few people have offered more printers and vacuums. The vacuums could be a pretty good source of ABS and large PP pieces. Wait 'n' see, I guess!