Author Topic: Buying 'damaged' equip deliberately??  (Read 2097 times)

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Offline GlennSprigg

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Buying 'damaged' equip deliberately??
« on: January 26, 2020, 12:54:40 pm »
Often I see something like a latest 'Tablet' on eBay, that is listed as 'Parts Only'.
They have to say that, as it is not 'working', but may be just a cracked screen!!
(Their further description may state that it is only the screen etc.)
Ok, I pay $99 instead of say $699, and can source a new Screen for $130 to fit 'myself' !
Can it be worth it, or should I/we steer clear?? Am sure there are past experiences!  :)
« Last Edit: January 26, 2020, 12:58:12 pm by GlennSprigg »
 

Offline ZigmundRat

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Re: Buying 'damaged' equip deliberately??
« Reply #1 on: January 26, 2020, 01:37:31 pm »
It can be worth it, however you must be willing to take a loss on an item too.  It could be that the thing you buy really is not working and should be considered a parts donor - not recipient. On the other hand you can often save a lot of money if you have the skills. But there’s always the risk of failure.

I’ve repaired screens on tablets, reflashed ereaders, resurrected a $1000 NAS, and swapped laptop screens. Then again I’ve also failed on other things. For me, I like fixing stuff. Sometimes it’s because I’d like to have “one of those” and I gamble I can can fix it, sometimes I know I can fix/sell and help finance the next toy, and sometimes it’s just for the challenge and education.

But I always ask myself: If I were to throw $60 out the window instead of spending it on this lot of bricked ereaders, am I ok with that? Because I may not be able to fix any of them- and that’s effectively the same.

Cheers!
 
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Online NiHaoMike

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Re: Buying 'damaged' equip deliberately??
« Reply #2 on: January 26, 2020, 02:40:30 pm »
Defpom does it with Macs. Apparently worth it even with the lower than average success rate.
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Offline Messtechniker

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Re: Buying 'damaged' equip deliberately??
« Reply #3 on: January 26, 2020, 02:56:20 pm »
Yep. Buying ailing or dead Koukaam NETIO-230A units for a song (around 5 EUR).
The capacitor on the secondary side of the PSU is always bulging nicely,
but does never kill anything else. The value of this capacitor and the
4 others differs depending on the type of PSU board installed.
Found three different PSU types to date.
Replace it and the four others and the thing sells for around 50 EUR.
Oops, just ruined my business. :palm:

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Offline Berni

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Re: Buying 'damaged' equip deliberately??
« Reply #4 on: January 26, 2020, 03:01:31 pm »
Yep i bought quite a bit of test equipment on ebay in a broken state because it was selling for cheap.

It is a bit of a gamble doing it since you usually have no idea what exactly is wrong. Some guessing does factor into avoiding faults that sound like could be very difficult to repair (Things like blown ASICs that basically need a new board to fix). Sometimes the fix is as simple as putting in a new fuse. Sometimes what you get is actually working fine but the seller had no way to test properly. Sometimes its a interesting troubleshooting hunt to find a faulty opamp or transistor using the service manual, those are really fun in my opinion. But sometimes the thing is simply beyond economic repair and you give up on it.

Its a fun hobby buying broken stuff and fixing it.
 
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Online ebastler

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Re: Buying 'damaged' equip deliberately??
« Reply #5 on: January 26, 2020, 03:11:30 pm »
Often I see something like a latest 'Tablet' on eBay, that is listed as 'Parts Only'.
They have to say that, as it is not 'working', but may be just a cracked screen!!
(Their further description may state that it is only the screen etc.)

As others have said, be prepared to absorb the occasional total loss. There are faults which you will not be able to successfully repair, e.g. if a gadget has been submersed and was left to corrode, or if there are bad solder joints below a BGA chip.

And be weary of sneaky sellers who lead you to the conclusion "ah yes, it's only a broken screen", while in reality not giving you any promise (let alone guarantee) to that extent. If all they say is "this unit has a broken screen" or "the only problem I'm aware of is a broken screen", that might just as well mean that a truck ran over it and all bets are off...
 
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Online jogri

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Re: Buying 'damaged' equip deliberately??
« Reply #6 on: January 26, 2020, 03:15:24 pm »
I bought most of my equipment broken (oscilloscopes, PSUs, DMMs, etc) and i managed to get most of it working again. It is a gamble, but as long as you stay away from hobbyists (i tried to fix it, didn't work) and just go for the "i don't know what it is, so i am selling it as broken"/ "doesn't turn on" offers you should be fine.

Another thing i look for when bidding on broken equipment is how much money i can get from the parts: Old school equipment often has quite expensive parts (precision potentiometers, etc), while a modern tablet is basically worthless unless you are lucky enough to find something willing to buy untested modules from you.
 
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Offline Brumby

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Re: Buying 'damaged' equip deliberately??
« Reply #7 on: January 26, 2020, 03:20:24 pm »
It is a punt.

If you can afford to write off the expense if it goes badly, then by all means take a shot.  Sometimes the actual fault is an easy fix (like replacing a fuse). Other times it can be a headache, take a lot of effort, require unobtanium parts, cost more than expected and/or just refuse to cooperate.

If you have the time, it might be worth asking about the typical failures of a bit of kit you're interested in - but then you risk alerting a competitor who will beat you to the punch.  (Remember, all posts accessible by non-supporter members are visible to anybody on the net.)
 
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Offline Berni

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Re: Buying 'damaged' equip deliberately??
« Reply #8 on: January 26, 2020, 03:48:16 pm »
Oh and also be careful of buying broken consumer electronics sold by random sellers for the cheapest price from all the broken ones.

People who get into the repair of consumer stuff like tablets or game consoles or whatever will do all the easy repairs first. Sometimes they will get a specimen that after the usual repair tricks still won't work, those they will often give up on and sell it on as a "for parts" unit to recoup the cost of it. You won't have any idea that you are buying one of those and its not something you want to attempt a repair on. Not only did the first guy already try all the easy fixes leaving you with the tough ones, but he may have also damaged something else in the process, giving you an additional fault to find.

I have even seen people sell a Xbox console "as is for parts" with the entire mainboard missing, yet having put in the effort to hotglue in all the connectors on the back so that it still looks perfectly fine from the outside (the connectors are probably ripped off the dead mainboard that he replaced with this one ripped out of there).

This sort of thing happens a lot less with test equipment, but you do occasionally stumble across other peoples repairs inside equipment.
 
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Offline nigelwright7557

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Re: Buying 'damaged' equip deliberately??
« Reply #9 on: January 26, 2020, 03:54:40 pm »
For spares or repair could mean anything.
From untested but fully working to absolute piece of junk which is unfixable.
Sometimes chips are obsolete.

I bought a 1980's Maplin 50 watt amplifier and couldn't get the transistors anywhere.
Someone suggested ebay and I found them all there !
Not sure how genuine the parts were but they worked ok.
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Online SilverSolder

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Re: Buying 'damaged' equip deliberately??
« Reply #10 on: January 26, 2020, 04:35:15 pm »
Oh and also be careful of buying broken consumer electronics sold by random sellers for the cheapest price from all the broken ones.

People who get into the repair of consumer stuff like tablets or game consoles or whatever will do all the easy repairs first. Sometimes they will get a specimen that after the usual repair tricks still won't work, those they will often give up on and sell it on as a "for parts" unit to recoup the cost of it. You won't have any idea that you are buying one of those and its not something you want to attempt a repair on. Not only did the first guy already try all the easy fixes leaving you with the tough ones, but he may have also damaged something else in the process, giving you an additional fault to find.

I have even seen people sell a Xbox console "as is for parts" with the entire mainboard missing, yet having put in the effort to hotglue in all the connectors on the back so that it still looks perfectly fine from the outside (the connectors are probably ripped off the dead mainboard that he replaced with this one ripped out of there).

This sort of thing happens a lot less with test equipment, but you do occasionally stumble across other peoples repairs inside equipment.

I have had that happen on eBay, and won my complaint case against seller on the basis of the item having major parts missing that was not described in the ad.

After all, if something is sold "for parts" and doesn't actually have any parts in it,  it isn't really living up to its description, is it?  :-)   eBay agreed and forced a refund.
 
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Online SiliconWizard

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Re: Buying 'damaged' equip deliberately??
« Reply #11 on: January 26, 2020, 04:50:19 pm »
Of course as said above: take the risk of complete loss. The thing may be damaged beyond economically-sensible repair.

Before buying, first step is to look up the most info you can gather on said equipment (service manuals, repair blogs/videos, cost of common spare parts, etc.)

One thing to note is that for gear that has high value (/high demand), the cost of "for parts" can still be pretty high on eBay. Look that up too. Evaluate the average price of a similar broken device. If you stumble upon one that sells for significantly less, chances are it's really really damaged.

 
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Online nctnico

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Re: Buying 'damaged' equip deliberately??
« Reply #12 on: January 26, 2020, 04:57:49 pm »
Often I see something like a latest 'Tablet' on eBay, that is listed as 'Parts Only'.
They have to say that, as it is not 'working', but may be just a cracked screen!!
(Their further description may state that it is only the screen etc.)
Ok, I pay $99 instead of say $699, and can source a new Screen for $130 to fit 'myself' !
Can it be worth it, or should I/we steer clear?? Am sure there are past experiences!  :)
It can be worth it but make sure it is worth your time. I have been buying & fixing broken equipment since the 90's. Nowadays mostly test equipment but in the past also computer equipment. You have to do your homework to learn about common problems and haggle a bit. Set a price for yourself upfront and walk away if you don't get it for that price. I've started walking for a few euros difference (and still got the item in the end because the seller called me back). I've also been fooled a couple of times by sellers claiming the piece of equipment has not worked on/opened. But I still managed to succeed fixing the equipment where someone else failed.
« Last Edit: January 26, 2020, 05:01:01 pm by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Offline H.O

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Re: Buying 'damaged' equip deliberately??
« Reply #13 on: January 26, 2020, 05:21:05 pm »
A while ago I made an offer on a "For parts" Agilent 34970A with multimeter option and the seller accepted. Had no idea what to expect really but was hoping for something stupidly simple like a blown fuse or busted supply rail. Worth a shot I thought.

When I picked it out of the box it felt light, opened it up only to find it was missing the transformer AND the multimeter board that the ad specifically said it had. Needless to say, not happy.

Not expecting much I contacted the seller and they said like "Oh, dear, we had no idea, we never opened it, terribly sorry" and refunded me the full purchace price PLUS part of the shipping and let me keep the unit. I still have some cash in in since I had to pay import tax and stuff but it could've been a lot worse.

So yeah, you take your chances. 
 
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Offline james_s

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Re: Buying 'damaged' equip deliberately??
« Reply #14 on: January 26, 2020, 06:52:02 pm »
I mostly seek out test equipment that is sold as-is/faulty, I like the challenge of repairing it and I have succeeded far more often than I have failed. Occasionally I lose and get something that I give up on repairing but overall I have come out way, way ahead. I could never justify owning most of this stuff if I had to pay retail for new gear or even fully tested guaranteed used stuff since most of it is essentially toys, I don't make a living off my personal gear.
 
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Offline Stray Electron

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Re: Buying 'damaged' equip deliberately??
« Reply #15 on: January 26, 2020, 08:59:49 pm »
Often I see something like a latest 'Tablet' on eBay, that is listed as 'Parts Only'.
They have to say that, as it is not 'working', but may be just a cracked screen!!
(Their further description may state that it is only the screen etc.)
Ok, I pay $99 instead of say $699, and can source a new Screen for $130 to fit 'myself' !
Can it be worth it, or should I/we steer clear?? Am sure there are past experiences!  :)

   Ebay used to be a good place to buy untested or nonworking equipment but not so much any more.  Years ago most of the sellers on E-bay were private individuals and they'd usually give you an honest description, at least within their level of expertise. But in the last five years or so there seems to a lot of full time, professional sellers on E-bay and most of them are just dumping junk IMO.  One thing that you do need to look for, particularly in electronic equipment, is equipment that has been opened up and the valuable parts stripped out and the left over hulk is sold on Ebay.  Another consideration, probably particularly for you guys down under, is the cost to ship the item to you and the customs charges. Within the US the shipping is reasonable and the customs charges are usually zero but some of things that I see from Australia and Europe make me wonder why the peasants (based on the way that they're treated by their own governments)  there haven't revolted yet.

  I probably buy at least 6, 7 or 8 items per month from E-bay but usually from sellers that I've dealt with and trust or CHEAP items.  There's no way that I will pay $200 to $300 (or more!) for a piece of equipment that I don't know anything about. In fact, this coming week I'm driving over and picking up 8 items that I just bought from one dealer.  He usually has GOOD equipment but he gets it on consignment and he's too lazy to test it so it's sold strictly as-is where-is.
 
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Offline edpalmer42

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Re: Buying 'damaged' equip deliberately??
« Reply #16 on: January 26, 2020, 09:20:23 pm »
I usually buy test equipment that's advertised as dead or flaky.  I use them as learning exercises to improve my knowledge in those areas.  I've bought power supplies, oscilloscopes, microwave counters, rubidium standards, even a cesium standard.  The repairs have varied from something as simple as plugging in or rearranging internal cables to replacing a specialized IC with a history of failure.

If I was buying consumer electronic or computer equipment, I'd be much less likely to buy a dead unit.  Consumer equipment is just not made to be repairable - particularly newer items like computers or laptops.

Regardless of what you're buying, you always have to go into it expecting to end up with nothing but scrap.  It's pure gambling.  Don't gamble with money you can't afford to lose.

Ed
 
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Offline Stray Electron

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Re: Buying 'damaged' equip deliberately??
« Reply #17 on: January 27, 2020, 02:05:36 am »
    Good points.

   I wouldn't buy any defective "consumer electronics".  First it's inexpensive to buy it new that it doesn't justify buying used or defective. Save your time for something more productive than repairing consumer grade crap.  Second, consumer grade electronics today also uses too many one-off, house brand marked parts and in general just isn't made to last long.

    I'm usually looking for (top grade) test equipment of one sort or another and I always look at see if there are service manuals available for the item and if that model has an known defects and I take that into consideration before buying the item.  HP, for example, makes some good TE but some models are known to be problematic and some of it has parts that have a known high failure rate and that are unobtainable.
 
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Offline Berni

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Re: Buying 'damaged' equip deliberately??
« Reply #18 on: January 27, 2020, 06:25:49 am »
Oh and you also see people like techmoan on youtube buying old HiFi equipment and fixing up any simple faults with them.

Since all of these old tape or disk based storage media are highly mechanical means that most of the faults he comes across are of mechanical nature. So fixing these doesn't really involve a whole lot of knowledge. Just take it apart, clean it, replace some fallen apart belts, lube up and jiggle around any jammed parts, glue together any broken plastic bits ..etc

Then there is also people like The8bitGuy that buy retro computers and fix them up. Tho he mostly focuses on the exterior of them to make them look as close to new as possible by extensive cleaning, bleaching plastic parts, replacing worn labels etc. But he will also do simple fixes like replacing bad caps, cleaning up leaked batteries and such. It can be turned into a business even since good condition retro computers sell for a pretty penny.
 

Offline GlennSprigg

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Re: Buying 'damaged' equip deliberately??
« Reply #19 on: January 28, 2020, 02:36:29 pm »
(original OP)
Years ago, I 'obtained' virtually for free, 15 HP laptops. Back then, they had a common fault
where the graphics chip had some soldering issues to the main MotherBoard. I put weights on
the chips, after disassembly, and in an order to 'ReFlow'. all worked fine, and sold each for $300!
And after setting up all software they would ever need.
Sometimes it works out!!!  8)
 

Online ebastler

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Re: Buying 'damaged' equip deliberately??
« Reply #20 on: January 28, 2020, 02:42:15 pm »
(original OP)
Years ago, I 'obtained' virtually for free, 15 HP laptops. Back then, they had a common fault
where the graphics chip had some soldering issues to the main MotherBoard. I put weights on
the chips, after disassembly, and in an order to 'ReFlow'. all worked fine, and sold each for $300!
And after setting up all software they would ever need.
Sometimes it works out!!!  8)

You mean you sold those laptops after a flaky "repair", which probably only kept them going for a few days or weeks, and after loading them with pirated software?  ::)

I don't even want to know how you "obtained" them in the first place.  :P
 
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Offline george.b

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Re: Buying 'damaged' equip deliberately??
« Reply #21 on: January 28, 2020, 03:06:44 pm »
You mean you sold those laptops after a flaky "repair", which probably only kept them going for a few days or weeks, and after loading them with pirated software?  ::)

I don't even want to know how you "obtained" them in the first place.  :P

To his luck, the "reflow" probably didn't even actually take place. BGAs with weights on top would do quite a number when the solder melted.

Let me guess, those had Nvidia G84/G86 GPUs?
 

Offline GlennSprigg

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Re: Buying 'damaged' equip deliberately??
« Reply #22 on: January 30, 2020, 01:37:40 pm »
How did I "obtain" the laptops??? Don't know what you 'assume', and/or need to question?...
I paid about $200 for those, along with other 2nd hand parts, from a small Computer Repair Shop
in Darwin, in the Northern-Territory, who was no longer 'trading', & getting rid of old stock. Hope that's OK...  :P

In Adelaide, (when I moved), the Graphics Chips were removed, cleaned, re-soldered & mounted utilizing
a professional Reflow Station at an acquaintances premises. (Doing them all at the same time/day).
The 'weight' was not a bloody brick for christ sake! It was about 50 Grams, just to assist the re-seating.
All purchasers from a few groups had my contact info, and were informed to let me know if there are any
problems. Into the following year, no-one had made any complaints!!  Well, except for 2, who had not
upkept the (free) Antivirus & Antimalware software, installed software riddled with viruses etc, too far gone!
So for 'free', I backed up their personal files, re-formatted, and set them all up again. (And educating them!).

Before 'selling' them, I simply re-installed Windows that was already on them, but now with a clean fresh slate.
I also set up what ever was wanted, in the way of Open-Source software like Open-Office, Inkscape, etc etc.
And of course Antivirus/Antimalware (free).  I'm sorry, but your 'assumptions' were all wrong. And offensive.  :palm:
 
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Online OwO

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Re: Buying 'damaged' equip deliberately??
« Reply #23 on: January 30, 2020, 03:37:27 pm »
Ok now I'm curious. Did you reball the chip or did you do it LGA style (remove all solder, apply paste, and reflow)? I was experimenting with resoldering a removed BGA this way. The "weights" sound like something you might do with LGA but not BGA. Did you apply paste with a stencil or just tin the pads with an iron? Maybe it's possible to get good soldering this way with little solder on the pads and a heavy weight. I'll have to try that.
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Offline george.b

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Re: Buying 'damaged' equip deliberately??
« Reply #24 on: January 30, 2020, 04:27:42 pm »
How did I "obtain" the laptops??? Don't know what you 'assume', and/or need to question?...
I paid about $200 for those, along with other 2nd hand parts, from a small Computer Repair Shop
in Darwin, in the Northern-Territory, who was no longer 'trading', & getting rid of old stock. Hope that's OK...  :P

I'm not the one who questioned your means of obtaining them, but writing "I 'obtained'", between quotation marks, does leave margin to assume you were being ironic. Quotation marks are meant either to quote someone/something, or for ironic effect. Although I didn't question it, that did make it seem suspicious to me as well, especially accompanied by "virtually for free". $200 doesn't count as "virtually for free" to me anyway, but oh well.

Quote
In Adelaide, (when I moved), the Graphics Chips were removed, cleaned, re-soldered & mounted utilizing
a professional Reflow Station at an acquaintances premises. (Doing them all at the same time/day).
The 'weight' was not a bloody brick for christ sake! It was about 50 Grams, just to assist the re-seating.

Well, then opposite to what you had said initially, you didn't just reflow, you did a complete rework. Either way, like OwO, I haven't heard of using weights for BGA rework, and to my knowledge that shouldn't be necessary if using the correct amount and type of flux paste.

You can understand how it sounded sketchy the way you initially put it, yes?
 
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