Photography - Seeing what's inside a canon auto focus lens

Opening up my old camera in an attempt to fix a stuck lens didn't end well, but it did make me want to open other stuff.

A mouldy $5 canon EF 35-80mm zoom seems like a good candidate.

I actually made it work better than it did when I started.

That's officially a successful repair.

We don't see many of those around here.

Odd feeling.

It turns out I wasn't being all that original when I used a lens cleaning cloth to make my macro lens hack light tight. It seems canon does something similar with a rubber band.

I attacked the rubber grip of the lens by lifting it up with a small flat head screwdriver, and sliding it up to reveal the three screws that control the zoom function.




Once that was done, the lens started falling apart. All it took was finding where the screws were in the first place. All the places I was told to start by the Internet were all false leads. I'm guessing things like lenses are made by the lowest bidder at the time, so these things probably change design all the time.

The only real stumbling block was this very fragile looking plug.

Luckily I had uncounted them when I pulled apart my point and shoot canon digital, and discovered they weren't really all that fragile.

I covered it with a folded bit of paper so the pliers wouldn't scratch the circuit off and pulled.




I also tried to avoid touching anything that looked like it might be copper. I have a feeling that touching stuff might lead to corrosion.

Probably just being paranoid, but it wasn't any really effort to avoid it. I should buy some cotton gloves for this kind of thing.

The little plug looks like this when it's unplugged.

Robot's are probably better at putting stuff like this back together, so I took a lot of photos as I was unbuilding it, so that I might have a chance of putting it back together.

That's a tip.

Take lots of photos of things as you pull them apart.

One part that was really fragile was this little bit of kit.

It's like a switch that drags it's contacts along a curved section of circuit board tracks so that the contacts keep in contact when you rotate the lens to zoom.

Or perhaps they adjust the aperture as you zoom, as I've noticed the available aperture range changes from one extreme of zoom to the other.


Who knows what it's really for, but I bent it convincingly out of shape when I was putting the thing back together.

I managed to fix it, but two of the pins will never be the same again.

This is the rear element. (the bit you can see a lens in on the left)

It's a cluster of ... three I think it was... lenses (two at least, but I think one was made of two), that I think also contains the aperture control.

The aperture control stuff must be in there, because there was nothing else with electronics in the lens.

I think this is me taking apart the lens that was really two lenses.

This things all had mould, but the other side of the one you can see in this pic had the most.

This is what I decided was the aperture bit.

I hope this isn't too technical for the reader.

Is bit even a word in this context...

Anyway, the remarkable thing is, after wiping down all the lenses with a lens cloth, it was actually an improvement.

That's the before and after shots with this lens.

Most of the milkiness is gone, but there is still a bit of mould on the front bunch of lenses, but I think I might hack them off and convert this thing to a macro lens.



I've been reading up on lenses, and how to hack bits off lenses that you dont want, and turn them into lenses that you do want.

Anyway, not a bad outcome for a $5, brand name, auto focus, zoom lens.

I cant wait to cut bit's off it.




120 things in 20 years - Where you will still find someone who thinks a lens doing it's auto focus thing is excitingly like having a robot. You also might find someone interested in photography trying to open a lens to see if there really is a man inside who does the focusing. (there's not by the way)

Electronics - Inverter repair

An inverter is a useful thing. It takes a stack of electrons from a 12 volt battery, and makes them look like the stuff that comes out of your wall, in my case at 240 volts.

How it does it is anyone's guess.

In my case it doesn't actually do that. In fact all it does, is take a stack of electrons from a 12 volt battery, and turn them into the smell of melting value.

I couldn't understand why a perfectly interesting looking device should fail.

Here it is pictured after it was repaired, but it also looked pretty much like that when it didn't work, but now I've given away the ending to this tale.

I fixed something - a first.

Note the total absence of left over bits - also a first.


Normally, the plan of attack is to open the device up, then put all the left over bits in the bin next to the now slightly more hollow, and slightly lighter device.

But this time was different.

To begin with I already knew why it was making all that melting plastic smell.

It was over heating.

The thing has a fan that is presumably meant to spin around a lot. At least I hope it's meant to spin around a lot. If it isn't meant to, it does now.

Perhaps I just invented something....

To make an artificial breeze, simply take a normal fan, and make it spin.

So...

The point is the fan wasn't spinning. I have a few fans that I've pulled out of junked computers, so I figured I'd just replace it. I can solder a bit now as well, so I figured it should be easy.

There were even some obvious screws to undo.

I used the electric screwdriver my mum bought me as part of a present.

Thanks mums everywhere. It even has a torch built in and you can never own enough torches, even when you will never use them.

I always thought electric screwdrivers were a bit pointless, but it turns out they are excellent. I've just never actually needed one before.

Unlike this project, my last had a few bits left over, and this was where the electric driver was really useful. It turns out there are a zillion screws inside stuff.

Pictured is all the leftover bits not including all the gears and shafts and all kinds of springs and stuff that might come in handy one day.

"What are the chances of any of it coming in handy?", I hear you ask.



But that's what they said about the 200 short lengths of black poly irrigation pipe I still have in the shed.

This thing used to be one of those fax, copier, printer combo devices that wasn't working any more. A friend was throwing it away, and thought my car was as good a place as any to throw it. It turns out there are some good motors and gears inside. I think there were five motors in there. That's them on the right. Maybe six motors. I'm planning on needing some motors, gears, and some shafts for making my solar tracking heliostat. There are also a stack of salvaged components used for tracking the placement of motors. The motor on the bottom right has a spoked arrangement that passes between a censor that detects light, and a light. The shadows cast by the spokes allow the system to track where the print head is. Or so I've read.

So much to learn. So much time. If you just stop watching TV.

Anyway, I've drifted off what pretends to be this post's topic...

Ok, so the fan wasn't spinning.

None of the fans I had would fit exactly, and would have to be trimmed (hacked and snapped with a pair of pliers) until they could be coaxed into duty.

I looked under that foil label and found the exposed end of the shaft.

I thought I'd drop in some oil before I replaced the fan to see if that's all it needed. It was.




The black, and off white cylinder in the front with the brown stain at the base is a capacitor.

I'm guessing it was also the source of the burnt plastic smell.

So that had to go. Luckily I have stacks of different capacitors from pulling apart some stuff, and had a duplicate.

A big component with large nicely spaced pins that proved easy to solder.

The thing went back together with no left over bits, and no spilt coffee added.

I realise this was a very simple repair, but it is something I would have sent to landfill before learning a bit of electronics over these last few months.

Here is a terrible photo of it charging a phone through it's transformer, and maybe a bit of Bigfoot's leg. Who can tell.



A 12v car battery supplying an inverter outputting 240v, then through the iPhone transformer to bring it back down to 5v.

Ok it's slightly inefficient, but the phone was the smallest thing I could take to the car to test it.

I rate this a total success.

Which is nice.




120 Things in 20 years - Bringing me one step closer each day to being able to take down a Terminator. Or repair an inverter. I need to win a 3D printer.

Electronics - Motor repair success

I fixed my broken motor that is meant to power the auger via the tiny gearbox that will deliver the fish food in my demand fish feeder.

Normally I prefer less complicated sentences.

But I'm all excited.

It turns out, the problem was there were simply too many parts.

Or more accurately one too many parts, and one that was simply in the way.

The silver bit was the one too many. I think that broke off the bit where the wires connect, and fell into the motor, generally clagging things up.





The little nylon washer creates part of the front bearing, but it made getting the brushes back on impossible, because it had to be put on after the brushes. That's an impossible path through the plastic front. I don't have the kinds of quantum tools that walking through walls requires. And if I did, I wouldn't waste my time with motor repairs. I'd do much more interesting stuff, like poking my head through the fridge to see if the light really does go off when the door is closed.

So be leaving out those two small parts, I managed to make my motor work.

Only two parts.

And they were tiny.

Those that know me will realise that's a pretty low number of excess bits after a repair. I think I did quite well.

So well in fact, that it looks like this when it's running.

That should do nicely.

What this all means, is that there is really no reason why I cant put this thing together today, and actually finish something.

Maybe.








120 Things in 20 years - If I keep repairing them, one day an electronic motor repair might leave me with enough parts to eventually build another motor. I should fix cars.

Electronics - My first repair

I have one of those digital TV recorders.

 Or at least I did.

It's always been a bit flaky with the occasional flicker of the images and a dunk dunk dunk to the sound every now and again. A few weeks ago it broke down completely. I thought I'd put my brand spanking new electronics knowledge to the test, and have a go at fixing it.

I opened the hood, and had a look for any signs of obvious damage. Mainly to me that meant looking for any components that had released their internal magic black smoke out into the world with some sign of burn marks, or melted plastic. I also looked for dust and dirt and anything else that looked out of place.

I was pleasantly surprised and a little excited to find this.

That black goo at the bottom of the large capacitor, was exactly the kind of thing I was looking for.

I did some research.






It turns out that that black goo was probably just something to do with the soldering, but what I did discover is that it's most often than not capacitors that let the team down when it comes to computers and things not working.

They way they let go, is like this.

See that slight swelling at the top. The "X" cut into the top of the component is because they tend to go pop, and the cuts release the pressure when they do.

Or at least that's what I read.

Either way, this cap is bursting at the seams, and all the others were flat.

This meant it was definitely in trouble and almost certainly the culprit.

All that was required was to but a $5 part and replace the bursting one and I should be in business.

If this works, I've just repaired a $300 item for $5 and should therefore be able to bill my household $120 for the repair, and pay back the hypothetical loan that 120 things in 20 years had to make to get started with the aquaponics, with my hypothetical earnings.

Actually I think that loan has been paid back already in salads and strawberries, but it's always good to provide Mrs 120 things in 20 years with some black numbers in the account book. Too many red numbers make my empire building long term hobby look like it might not only use all he buckets and space in the shed, make mess, and create danger zones all over the yard, but it might also be bankrupt.

Bankrupt hobby empires are never a good look.


Actually not a bad job if you ask me.

So, after soldering the new part in place and trimming the component pins, my 20 second repair was ready for a test.










Drumroll please..........




Exciting isn't it.............

Nothing.


 









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