EEVblog #488 - Dumpster Dive Parts Salvage

[EEVblog]

Does basic office equipment have any salvageable parts?
Dave dumpster dives to find out.

[duskglow]

I've gotten lots of good parts out of dumpster diving.  And, once, cockroaches.  From there, I learned to be careful.

[BravoV]

When it comes salvaging printer/fax/laser jet printers, I also grabbed those roller metal rods especially the one where the moving print/scan head were sitting on, they're thick solid stainless steel. They wont rust, very strong and really stiff, worth salvaging.

[JuanPC]

https://www.youtube.com/watch?feature=player_detailpage&v=7wAPWTzK8iI#t=882s
Minute 14:42
100. point to point.

the feedback circuit in my Stanton ST.150 turntable has similar optical mechanism, instead of the magnetic feedback of the Technics SL-1200 MK2,
i always wanted to increase "decrease wow/flutter" of the Stanton to the level/accuracy of the Technics SP10_MK3 or even MK2.
how low wow/flutter can go...

what is the secret, just a heavyer plate?

[Stonent]

I've gotten lots of good parts out of dumpster diving.  And, once, cockroaches.  From there, I learned to be careful.

What? You wasted perfectly good cockroaches?



http://wiki.backyardbrains.com/RoboRoach_Surgery

[westfw]

I like to save the random cables with female connectors on them; they're useful for connecting random things to the male pins that tend to stick out of many development/evaluation boards.  Or you can use them like LED sockets/etc.

[Oracle]

maybe the fluorescent tube worth something if you sell some of those...

[sleemanj]

Co-incidentally I ripped apart a stack of multi function printers in the weekend (and then this week, promptly bought another 4 for a buck each to replenish the stack of printers to tear apart).

The motors and shafts in them always come in handy.  I used to strip the carriages right down but now I keep the head and it's drive motor and quadrature encoder in one place (but strip off all the feed mechanism etc).  The scanner heads I usually keep in one piece and they get stacked in the shed.

One particularly nice find of late is that brother printers in the later DCP type range (DCP-165...) have really nice little double-ended motors with a covered quadrature encoder disc and reader on one end in them, nice little package (I've seen these for sale in China as a module too, probably also ripped out of printers).

Stripping down printers is a nice winters job, only problem is you wind up with empty printer shells.  I usually break those down into flat bits as best I can and shove them in the shed somewhere, in the vague hope that one day one of those "scrap ABS to 3d printer filament" type deals might be usable.  That said I did manage to eat up a couple cases by using a holesaw to cut discs of different sizes, then used acetone to glue them togethor to make crude but functional pulleys

The doors of my car are held on with hinge pins cut from one of the shafts in a printer, the bonnet catch is also cut out of bits of aluminium from some sacrificed inkjet.  Plenty more uses for printer gubbins than just electronics :-)

[ChrisGreece52]

I took apart my broken HP Photosmart and did not keep the lcd

[kioan]

Some have asked in the youtube comments about the heating elements used in the laser printers so I'm also posting here a photo of two such halogen lamps for anyone interested.
They are double-ended tubular lamps 27.5cm in length with R7S base




And a photo of my favorite tools for quick dumpster dives

[FrankBuss]

The microcontroller boards could be hacked and reused, sometimes they are quite powerful. Some people have done this with a digital picture frame (I know one of the hackers) :

http://hackaday.com/2012/01/10/this-digital-picture-frame-runs-linux-better-than-you-might-think/

Probably someone could build a pick-and-place machine with all these motors and stuff.

[free_electron]

Another good usage is to keep one for when you need to buy one... There are frequently 'upgrade incentives' like 50$ off if you turn in your old one. Hand off the really old one and rip apart the younger one.

[Rasz]

if anyone is interested  those small AUO LCDs have a weird analog RGB interface
that cob (Chip On Board) chip is probably a companion driver converting serial to analog RGB along with doing buttons io and stuff

[krivx]

Does any have any nice project write-ups based on salvaged parts? I often see people talk about tearing about printers and scanners but actually seeing the parts in use is much less common

[Rasz]

Does any have any nice project write-ups based on salvaged parts? I often see people talk about tearing about printers and scanners but actually seeing the parts in use is much less common

/looks at 8 copy paper boxes full of parts just in my room alone

thats a big no no, we salvage parts to collect them. Hoarding is a long standing engineering tradition!

[SeanB]

I am using them as spare parts, got quite a few others going again from the old ones, and have done a lot of quick work using the bits on the boards. If I need a cap quickly just to check it is easy to grab one off a board and check it then use it. Done many power supplies that way, the printer parts are often a good quality part. The steel rods have come in handy as the makings for metalwork, drifts to remove bearings and one is in use as an emergency brake release rod on the lift.

[dentaku]

I like clicky mechanical buttons. For me those where the most useful parts because you can pop them right into a breadboard. Of course I'm very beginner.
I love finding good faders and pots best though. Nothing beats finding good sturdy linear potentiometers for free and nice looking knobs from audio equipment.

[cthree]

I know of a shipping container electronics recycle bin where people drop off their old junk unfortunately it's 45 minutes drive from my house I'd post the location but you've got to protect your stash

[johnwa]

These printers are always a good source of parts. Unfortunately, the newer ones are very cheaply built, older ones are best for really solid components. I still have an old HP laserjet IID waiting to be taken apart, that thing is massive!

In terms of parts/subassemblies to salvage, the fuser unit can be repurposed into a laminator quite easily. I have one that I used for toner transfer PCBs. You didn't mention the crystals on the boards Dave, I feel these are always worth grabbing.

My approach to the salvaging of PCB mounted components has changed somewhat over the years. I used to methodically desolder all of the components with a heat gun, and sort them out into my parts drawers. However, I got such a backlog of PCBs to process, that I just decided to keep the intact boards, and rummage through them all whenever I need a particular component in a hurry. I keep two categories of PCBs: ones that contain functioning subsystems, and ones that are only for parts.

Regarding the spring clip with the resistor and diode, it looks like part of the HV electrostatic circuitry, with the clips making contact with the toner cartridge. I think that resistor may have been a HV type.

It is interesting to note that everything is moving towards DC motors for positioning. All the old printers used to use stepper motors for this. I suppose the electronics required to output a bitstream synchronised to the motor feedback signal is now cheaper than using a stepper.

[amyk]

It is interesting to note that everything is moving towards DC motors for positioning. All the old printers used to use stepper motors for this. I suppose the electronics required to output a bitstream synchronised to the motor feedback signal is now cheaper than using a stepper.

Don't forget the price of the encoder and driver circuitry too. The traditional setup was a stepper + multiphase bridge + driver ASIC, now it's a DC motor + encoder + H-bridge + CPU.

[vk3yedotcom]

A great video on the under-stated pleasure of pulling stuff apart.   

There are times (eg an hour before bedtime) when it's too late to start a new project but it's too early to retire.   Or you might be slightly tired and not be up to solving the problems of the latest new or rebuilt project.

On such occasional pulling large stuff apart is not that intellectually demanding and is great fun due to the mystery element - you never know what exactly you'll find.  The main challenge is forcing plastic stuff apart when you can't find the screw that holds the thing together. One might occasionally have to resort to violence with screwdrivers and hammers if the case is expendable.

Beginners note carefully. The floor is absolutely the best place to pull medium - large sized stuff apart. Things can't fall any further and you can reach stuff over a larger area.  The tarp is a good idea.  It also brings back childhood memories of playing with lego, especially if you step on something! 

[Paul Moir]

... I suppose the electronics required to output a bitstream synchronised to the motor feedback signal is now cheaper than using a stepper.

I've always wondered exactly how these worked.  There is no feedback mechanism I can see.  Usually just two wires going to the motor.

Old CRT monitors are my favourite source for through hole parts to grab.  Single sided boards make pulling stuff easy. 

[duskglow]

I've found that single sided boards can be ridiculously easy, depending on whether the leads are folded over.  If they're not, just go over it with an air gun and slam the board down.  Parts will just fall out.

[edpalmer42]

Some years ago I took apart an HP 2687A laser printer from about 1983.  Original cost was $12 800.  It was so old they hadn't come up with the name 'Laserjet' yet.  When I opened the laser enclosure, I was stunned to find a HeNe laser tube instead of a laser diode!  I've still got the tube and power supply.  Works great!

Ed

[TheWelly888]

I've pulled apart plenty of gear and even salvaged components from decommisioned medical equipment at work that I have so much junk at home and no time to play with them!