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!

[miceuz]

oh man... where do I put all those BJT power transistors?

boards with smd components frequently come handy when you need an odd value SMD resistor.

[staze]

The resistor/diode piece from the laser printer is exactly as you said. It's the contact between power and the fuser, and if you get an overheat on the fuser, that resistor will burn out and save you from a fire. That part is pretty useful if you do printer repair... otherwise... worthless. =P

[staze]

I'd grab that Phaser and tear it down... could be cool since they use wax based ink... so there are micro heaters, etc. Very different than your typical printer. =)

[SeanB]

That Phaser is a laser printer, not wax. I have one of the wax ones at work, it is a 60kg shelf filler, too expensive to run, though I do have some of the "Free Black wax sticks" around for it.

[Stonent]

too expensive to run, though I do have some of the "Free Black wax sticks" around for it.

I used to do all my printing of work orders on the Phaser 850 we had years ago.  People used to just freak out at me doing that! Trying to explain to me how expensive the ink was for it and such and should print to the LJ4si sitting next to it and the Phaser was reserved for "special projects" only.  I tried numerous times to explain to them that the cartridges for the 4si were about $150 and the black wax was free. But they didn't understand.

One major undoing of the use of the Phaser printers at that employer was that we couldn't get people to understand that just because you can force a Phaser 350 wax block into a 850 by breaking the corners off you should not do it (or vice versa)

One way caused the wax to smoke and carbonize inside the printer because it got too hot, the other way caused the wax to solidify part way in the nozzles because the temperature was too low.

So after having a $1000 printer overhaul done by Tek to get the printer running again they'd be all pissed at Tek for designing printers with different temperature ranges.  Again I had to explain to them that you couldn't run transparencies through a Phaser 350 because the wax was so hot it would melt the plastic, with the 800 series the lower temperature wax wouldn't melt or warp the transparencies.

I used to tell people they were "printing with crayons" and take the blocks and doodle little pictures on the paper with them.

I seem to also remember working on some kind of Tek printer that had a sort of plastic ribbon in various colors. I think that was the Phaser 440.

I wonder if you could turn a Phaser printer in to some sort of 3D wax printer if you mounted the print head on to rails and used a stepper motor?

[SeanB]

The 440 is a dye sublimation printer, using a ribbon that was alternating CMY dye sheets that were transferred to the paper by a thermal print head. The 340 print head will be usable as a 3d printer as is, as it is mounted on a rail set, and works by having about 65 nozzles that are used to place a drop of wax on the drum as it turns, then the whole head is stepped to the next column and deposits a new row. Takes about 30 turns of the drum to build up the complete page image on the oiled surface, then the paper feeder picks up a page, heats it up to just short of the wax melting point and feeds it to run in contact to transfer the image. After the page is fed the maintenance tray moves up, contacts the drum with a wiper blade to remove old wax and oil for a turn or three, then moves up further to place a new layer of silicone transfer oil onto the drum with a felting pad fed from a bag of oil.

The only problem is you have to keep the head level, as it has the liquid wax in open topped channels ( with a cover but it relies on the levels to feed the wax to the piezo ejectors) and has a channel arrangement to feed liquid wax down from the PTC and thick film wax ceramic knives. Has a tendency to get clogged heads, so you have a cleaning mode that prints a whole blob of wax into a cleaning cup with a vacuum pump that then deposits it into the maintenance tray. Even has a check for the heads that prints a series of coloured bars with head numbers. Not much use as you cannot clean an individual head, only all at once, and this uses about 1/4 of a block of each colour.

[Stonent]

I do now remember having to empty a waste tray on these printers.

[kriebz]

Another interesting part to look for on new-ish multifunctions and scanners is in the scan assembly, instead of a CCFL bulb and a color sensor, there is a light guide fed by an LED triple and a monochrome sensor.  This is a really neat part and you can PWM your way to any color of the rainbow.

[Drewbie]

A lot of the newer machines have a cpld on-board, wireless, and a JTAG connector.

[SeanB]

Sent 8 of these to the scrapyard today............

Obsolete, no longer in use any more and eclipsed by technology, but they were incredible for the time they were designed, and were heavily used.


DSC00147 by SeanB_ZA, on Flickr

[GrandTheftAuto4life]

I'm interested in the part at 18:40 - 19:27

I don't quite see what it's supposed to do, but I'd like to know...