Salvaging used components - Good idea?

[dr pepper]

Nice one throbs, I really like to re-appropriate stuff, that is proof it works.
I have just aquired a vcr, a dvd player and I think a sky box to process next week when I'm on nights, I think I might start salvaging smd's too, whats your technique hot air like I use for through hole?

Honduras, I've done some rf and smps power boards 'dead bug', I have a big old hole punch meant for punching holes in a 100 sheets of paper, it makes nice little round islands in copper clad board, have a look at your goodwill or something.

 

[Honduras]

I use a big illuminated magnifier so I can see what I'm doing, hold the components down with the tip of a small craft knife so they don't shift easily. Soldering would definitely be easier with more spaced out parts and larger lands, so you could over-size your pads. (eg, I've been making boards for 0805, but occasionally have to use 0604, so there is a lot more room on the pads!)

By Brooklyn style, I take you mean "dead bug with islands"? I've seen diamond coated mini hole saws, a few mm across, so you could use one of those.

The 'Brooklyn Style' I use is based on single sided copper clad islands, usually cut with a nibbler, glued to a full copper clad board. components and connections are made to the islands.

 

[Honduras]

Nice one throbs, I really like to re-appropriate stuff, that is proof it works.
I have just aquired a vcr, a dvd player and I think a sky box to process next week when I'm on nights, I think I might start salvaging smd's too, whats your technique hot air like I use for through hole?

Honduras, I've done some rf and smps power boards 'dead bug', I have a big old hole punch meant for punching holes in a 100 sheets of paper, it makes nice little round islands in copper clad board, have a look at your goodwill or something.

That's a great idea. TYVM.

 

[throbscottle]

I recovered a load of stuff using a hot air gun, and scraping the components off with a knife, but the trouble is they tend to get soldered to each other. It's nice and easy though. I've seen video demo's of someone heating the board up then banging it edge down, all the parts fall off. Hasn't worked for me they've been glued I think. Best tool by far for individual devices is the soldering iron with a bit that has a long straight edge (Hakko shape K) because it can melt several pins at one time. SOT-23 I unsolder the pin on it's own first, lifting the device with the tip of a knife, then unsolder the other 2 pins together, using the knife tip to drag it away. When I've tried it the other way round, ie the 2 pins first, the other one tends to break . The technique I've found works for smd electrolytics and inductors is to slowly pre-heat the board with the heat gun, then unsolder it with the iron, else the heat from the iron just won't penetrate, and the heat gun on it's own is too much brute force. The 4066 in the picture I removed by heating with the heat gun and lifting it with the knife tip.

But the biggest problem I have is storage - smd cases are expensive! I started a thread about it a while ago. I seriously considered glassene bags as someone suggested, but I'm having doubts. So the ones I removed with the heat gun are still mixed up in their little make-up pot, all the others are still attached to their boards. Go hunting through the boards often enough you end up with an idea where to find what anyway. I want to try making multi-hole containers by drilling wide shallow holes in a piece of wood, but I'd need lids for them and don't know what to use.

 

[dr pepper]

I put the board in the vice, solder side towards me, heat the solder wide with the air gun then pull out the comps with a pair of bird beaks.

 

[Honduras]

I recovered a load of stuff using a hot air gun, and scraping the components off with a knife, but the trouble is they tend to get soldered to each other. It's nice and easy though. I've seen video demo's of someone heating the board up then banging it edge down, all the parts fall off. Hasn't worked for me they've been glued I think. Best tool by far for individual devices is the soldering iron with a bit that has a long straight edge (Hakko shape K) because it can melt several pins at one time. SOT-23 I unsolder the pin on it's own first, lifting the device with the tip of a knife, then unsolder the other 2 pins together, using the knife tip to drag it away. When I've tried it the other way round, ie the 2 pins first, the other one tends to break . The technique I've found works for smd electrolytics and inductors is to slowly pre-heat the board with the heat gun, then unsolder it with the iron, else the heat from the iron just won't penetrate, and the heat gun on it's own is too much brute force. The 4066 in the picture I removed by heating with the heat gun and lifting it with the knife tip.

But the biggest problem I have is storage - smd cases are expensive! I started a thread about it a while ago. I seriously considered glassene bags as someone suggested, but I'm having doubts. So the ones I removed with the heat gun are still mixed up in their little make-up pot, all the others are still attached to their boards. Go hunting through the boards often enough you end up with an idea where to find what anyway. I want to try making multi-hole containers by drilling wide shallow holes in a piece of wood, but I'd need lids for them and don't know what to use.

You know, I think the biggest problem facing electronics hobbyists is an inventory system. Even if you have one, and then pop 100 SMDs off a board in one day, you still have to enter the data by hand and decide where to store the devices so that you can find them easily.

 

[throbscottle]

Not to mention adjusting the figures when you use something. Personally I don't think it's worth the effort. Being dyslexic gives me a problem with using, and especially with maintaining, lists of any sort, also I'd forget to use and maintain it. As a hobbyist I don't use enough of anything, or often enough, for it to be worth the effort anyway. That said, I do have a list of chips I've recovered and smd transistors I've identified, but only so I know what they are without having to look each one up every time...

 

[atferrari]

I would love to do Surface Mount, but I have not found a way. (Old and creaky. Poor eyesight.)

I had thought to change to Brooklyn Style, but It's hard to find 'islands' small enough.

Suggestions?

The punching system did not work for me because I never got a single really round piece of claded board. I found that cutting discarded/used pieces of stripboard you get something that has a shape and size more or less regular. Not the best, I admit but is what I found handy.

This video could give you some ideas. I like those circular islands.

 

[throbscottle]

How about using a plug cutter? They are made for woodworking, but could make circles like you want - in various sizes, too!

 

[atferrari]

How about using a plug cutter? They are made for woodworking, but could make circles like you want - in various sizes, too!

Yes, I have to look for them.

 

[dr pepper]

I just picked up a enormous rear projection telly, I'll be busy salvaging from that.

 

[atferrari]

Could you show just few pictures?

 

[throbscottle]

Don't forget to make a death ray! https://www.instructables.com/id/Solar-Death-Ray-TV-Fresnel-Lens/

 

[dr pepper]

The last one I pulled to bits busted, I'll be a bit more carefull with this lens.
My mrs had the same tv before we were married, one night while we were courting and tucking into our McD's the stupid thing blew up, I ended u[ stripping it so I know what sort of stuff's in there.
I'll take a couple of pics yes.

 

[dr pepper]

Wasnt all that exciting, just one ferrite of size and thats probably air gapped as it has one switching trans so it'll be a flyback.
The optical assy looks interesting, there is only one lopty, it goes through 2 boxes, one probably a distributor/multiplier, not sure what the other one does it has 6 pots on it, maybe its the usual screen/focus one per crt.
Some high quality lenses in those fittings, I didnt take the fresnel lens or the mirror.

 

[Honduras]

How about using a plug cutter? They are made for woodworking, but could make circles like you want - in various sizes, too!

I'm going to try one. I'll let you know.

 

[throbscottle]

I feel the need to eat my words regarding an inventory system, having been hunting for something and discovered things I'd forgotten about! Been having a really dyslexic couple of days, got quite confused. Sigh.

 

[Honduras]

I feel the need to eat my words regarding an inventory system, having been hunting for something and discovered things I'd forgotten about! Been having a really dyslexic couple of days, got quite confused. Sigh.

You are definitely right about all the hassles involved, but so many times I have ordered an item, then found out that I already had 100 of them.

 

[dr pepper]

Dont worry about it, I have a stock system where I work and still now and then I order stuff that I allready have 100 off.
I'm going to skip a load of stuff as its been sat on shelfs so long they are either full of dust and unuseable or the machines they are for are no longer in service.

 

[Honduras]

Dont worry about it, I have a stock system where I work and still now and then I order stuff that I allready have 100 off.
I'm going to skip a load of stuff as its been sat on shelfs so long they are either full of dust and unuseable or the machines they are for are no longer in service.

Consider an auction. Anything is better than nothing.