In the last episode, I started restoring this old Osborne 1 computer, and I managed to finish
the keyboard.
And although it looked better, the keys came out sort of marbled looking.
In this episode, I'll be tacking the rest of the computer.
So let's get right to it.
The first thing you need to do to disassemble an Osborne is to remove these knobs for the
brightness and contrast.
Then you can remove the screws holding the face of the computer on.
And it just pulls out like this.
Mine has a composite video option, I'm not sure if that is standard or not, but anyway
it has to be unplugged.
Anyway, then the rest of the face just comes off.
Next you need to turn the unit upside down and there are 5 screws to remove.
And believe it or not, that's all you have to do take the case off.
These pieces in the back just slide out.
There's a little ground wire here that needs to be unplugged.
And this entire handle piece just comes right out.
Notice that around the edge you can see the original color of the Osborne where it has
not been exposed to UV light.
With any luck I can get the rest of the case to look like that.
I'll need to remove this ribbon cable for the floppy drives.
Although this looks really similar to ribbon cables on PC floppy drives of the era, this
cable actually provides power as well as data.
The logic board itself is just held in by 4 screws.
Just need to unplug power and the video cable.
OK, so once the logic board is out, I can remove the rest of the case.
There wasn't anything holding it on, it was just sitting in there, but I didn't
feel comfortable having the computer sit on top of the logic board, so that's why I
took it out first.
Taking a look at this board, you may notice this large daughter board, this is actually
an aftermarket product that gives the Osborne 80 column video.
The other small daughter board you see there is another add on, although this one is from
Osborne itself and it's a double-density floppy controller.
You see, the early models could only use single density disks.
I'm sorry I didn't get a better photo of that, I had meant to get a better shot
and never got around to it.
I'll just de-route this floppy ribbon cable and remove it.
And now I'll give you the first look at this tiny little CRT.
It's quite long compared to it's viewing area.
The next thing I needed to do was remove these floppy drives.
Normally, if you were just wanting to retrobrite the case or something, you could just leave
these in.
But, one of these drives is not working and so I need to remove it and have a look.
And here's what these things look like from the underside.
The belts are still good on both of the drives.
Now I'm going to unplug this power supply.
This is the last component that I will be removing.
It's just held onto the case by 4 screws.
And there it is.
I'll just cut this zip-tie here and it will be free.
These mains power lines look like they are soldered in, but they aren't.
If you pull, like this, they'll pop loose.
Ok, so the power supply is finally completely removed.
So let's have a look at it.
See this capacitor here?
This is the one that blew up and filled my house with a horrible smelling smoke.
I had to open the windows and turn all of the fans on to get the smell out of my house.
Apparently this is a common failure on this, in fact a friend of mine had warned me not
to even use the computer until I removed that capacitor.
I didn't take his advice and, well, sure enough, after about 10 minutes of using the
computer, it blew up.
So I'm going to go ahead and remove it now.
The interesting thing, and I suppose it is good news, about this capacitor is that it
isn't really needed.
It's a line-filter capacitor that filters the A/C power going into the Osborne.
It's like your appendix in that if it is giving problems, it's best to just remove
it.
Some soldering wick made quick work of this, and the capacitor came out very easily.
And here's what it looks like.
It apparently blew up from both sides.
OK, next on my agenda is to clean the CRT.
It's hard to tell on camera, but it's pretty dirty.
And the trouble is, there is this plastic cover that sort of hovers right in front of
the CRT with an air gap, so dust and stuff can accumulate between the two over a long
period of time.
It's just held on by double-sided tape.
I just removed the tape and then followed up with some alcohol to get the sticky goo
off.
And that seemed to work pretty well.
I was finally able to clean the CRT, probably for the first time ever since this computer
was made.
And now you can see this little cover and even still it is hard to see on camera but
this thing is filthy.
So I'll give it a good cleaning with windex too.
OK, so I had some double-sided tape in the house already, but I noticed it was only half
as thick as the stuff they used.
So I just took two pieces and stuck them together, and I think that will work just fine as it
almost perfectly matches the thickness of the original.
I had to be very careful placing the cover back on because I would likely only get one
shot at this to get it lined up correctly.
This sort of tape isn't very forgiving if you want to pull it back off.
And there we have it.
I think that will make the video image much cleaner now.
Next, I wanted to turn my attention to these floppy drives.
They have these little metal covers on them, which I thought I should remove to have a
better look.
And it looks like I accidentally left the word star disk in this one.
So there were two problems I had to deal with here.
One was the drive motor itself.
It was seized up and wouldn't spin.
But once I managed to rotate it a few times with my fingers it broke free and now it seems
fine.
And the other problem, believe it or not, was the head mechanism here was seized up
on these rails and wouldn't move.
Again, after I broke it free it will now move, but it's still very stiff.
So what I'm going to do is use some of this lithium grease and I'm just going to put
some of it on these rails here in all 4 places where it makes contact.
And it doesn't need much.
A little goes a long way.
Then I'll just need to move the head back and forth a few times.
And, I can immediately tell after the 3rd or 4th time I moved it that the amount of
friction has been greatly reduced.
Yeah, now it's moving a lot more easily.
I did this to both drives, and also lubed up every other part I could see that might
need it.
OK, so next I wanted to turn my attention to this yucky power panel.
I needed to remove the plastic bezel and there appeared to be just two screws.
However, I realized there were two more under this old crusty sticker.
And since I don't even know what the purpose of this sticker is, I decided just to remove
it completely.
All right, so with the two parts separated it will be much easier to clean.
My first goal should be to get rid of the rest of this sticker, but some of it is holding
on for dear life, so I'll spray some WD-40 on there and let it sit for a few minutes.
That helped a lot as I was able to easily peel the rest of the large pieces up with
no problem.
After that I could just rinse the whole thing off in the sink and use a scrub brush to get
some of the more stubborn gunk.
And just drying it off now, I can already tell it looks 100 times better.
So yeah, and there we go.
Sure, it needs some retobrite, but it looks much better already.
This metal piece here was gross too, so I just sprayed it down with some windex and
it cleaned right up.
And here's this piece, all finished up.
Next I'm going to take a look at these two smaller pieces.
This is the carry handle for the computer, and this piece here is the power port cover.
It's really too bad I can't unscrew this handle from the plastic, it appears to be
riveted in place.
So the first thing I'll do is just clean it up as much as possible.
And it already looks tons better.
The little metal covers are also all rusted up.
Believe it or not I scrubbed this one here with just alcohol and managed to clean it
up quite a bit.
You can see how it looks compared to the other one, which I haven't started on yet.
I actually came back and followed that up with some baking soda and worked it over with
a tooth brush for several minutes.
And we're about to find out how effective that was.
You know, it's not bad, actually.
It doesn't look new, but it looks much better.
Moving on, it's time to tackle the main case.
I started with using the hose outside as it was the quickest way to get most of the dust
and gunk off.
I followed that up with my usual windex and alcohol routine.
But I wanted to show you some of the pieces had black spots like this that refused to
come off.
A lot of people always tell me to use a magic eraser for those.
But I prefer to use baking soda.
I've just found that usually it is easier to work with, even though it does leave a
mess.
Plus it's cheap and available almost anywhere.
And, as you can see, it worked pretty darned well on this.
I had the same issue with the main case as well, as you can see I tackled it with some
alcohol, but still ended up with lots of little scuff spots.
So I ended up using baking soda on pretty much the whole case.
This took a good 20 minutes to do, but the results were very good, as you can see here.
OK, so here are all of the parts that are going to require retrobriting.
Now, I have a few things to say about the retrobrite process.
I have had hundreds of emails telling me supposedly better ways to do it.
I've been wanting to try some of these, but at the same time I feel some of the suggestions
are risky and I don't want to try them on something I care about.
I'd rather use a technique that is tried and true, at least for me.
So I'm going to be doing this my usual way.
Granted, my keys turned out marbled looking using this technique, but the keyboard case
itself was fine.
And since these are all the same type of plastic, it should be fine as well.
The first part to finish was the power panel.
It had the least amount of yellowing, so that isn't surprising.
After rising it off, I went ahead and mounted it back to the metal parts.
So, at this point in the project, everything was going pretty well.
I mean, I'd managed to clean the screen, removed that blown capacitor, I even got both
of the floppy drives working, and I even managed to shine up those little metal pieces.
So, I mean, things were working great!
Unfortunately, this is kind of the point in the project where things went downhill.
The first problem I noticed when checking up on my retrobrite was that the leather handle
seemed to be coming apart.
So I thought I'd better end the treatment on this part early and rinse it off and have
a look.
So, this is not done retrobriting, even though you can tell it looks better.
But I wanted to get a look at this leather.
It appears ripped in places.
I started to wonder if it was like that before and maybe the retorting just made the material
underneath a brighter color so that now it shows through, but I went back and examined
some earlier footage and you can see that is definitely not the case.
So the peroxide was definitely damaging the leather here.
So, in theory I could get some new leather and re-cover the handle with it and stitch
it all together, but I don't really know how to do that very well.
I'm going to look around and see if maybe I can find somebody who can do that for me.
I don't think it should be too difficult for someone who's experienced in working
with leather, so that's something that can be fixed.
And, by the way, when I show mistakes like this it's so that you guys won't make
the same mistakes, so another lesson learned!
So the case had been out in the sun for about 4 hours, and I thought it was time to rinse
it off and have a look.
So, even though these pieces are like 90% complete, you can see they are suffering from
the streaking effect, the main case had some too.
Several people had been suggesting to me to stop using the plastic wrap and just apply
the cream directly to the surface.
Now, keep in mind the entire purpose of the plastic wrap is to keep the peroxide from
evaporating.
So with this method, I would have to come out every 5 to 10 minutes and apply fresh
cream and spread it all around with the paint brush.
So, essentially you are making a trade off between how much time you spend working on
it, and the end result.
I could tell that after just 30 minutes, this stuff was becoming very thick, even though
I had already added fresh cream several times.
Oh, and it left a bunch of cream on my driveway that I had to rinse off.
And here's the result.
Yeah, it looks terrible.
In fact, it actually looks worse than it did after my first treatment using the plastic
wrap.
And here's one of the smaller pieces.
So, it's no secret that the best way to do retrobriting, at least of all of the methods
currently known, is total submersion in hydrogen peroxide.
The problem is with the larger items, you need a really big container and quite a bit
of hydrogen peroxide.
So it isn't really feasible.
But I thought I'd test these smaller pieces and see if I could fix the damage.
The bag started leaking, so I eventually switched to this little container.
After a few hours in the sun, I rinsed it off and you can see this piece definitely
looks better.
I also did this other little piece and it looks better to, not perfect, but better.
So I think that proves that it is possible to reverse some of the streaks in the future
when I develop a better method for handling these larger pieces.
But for the time being, I decided to go ahead and re-assemble the computer.
I don't have any more time to mess with these case pieces right now, but it is something
I plan to revisit in a few months.
On the bright side, this computer is very easy to take apart, at least as far as the
case pieces are concerned.
So there's definitely no harm in re-assembling it.
And so here's the final result.
Some parts of the computer look almost brand new.
While other parts look streaked.
But at least the computer is clean now and doesn't make me cringe to use it.
This part here actually looks really nice.
And so does this rear power port area.
I'll go ahead and power it on, and you can see the screen is nice and sharp.
So, I wanted to take a moment to talk about what actually causes the streaking, whether
you're using the plastic wrap or not.
Imagine a cross-section of the retrobriting process.
Here's your yellowed plastic, and here's your plastic wrap.
And ideally you'd have a perfect layer of cream in here.
Well, it doesn't really work out that way.
In fact, it's more like this.
And these raised areas have more peroxide so it will react more with the plastic making
bright spots.
These lower areas have less peroxide so it will become spent faster, leaving dark spots.
If you forgo the plastic wrap, you get a similar problem.
Let me demonstrate with this mustard.
Now, imagine after a while it has already reacted with the plastic and I'll represent
the spent chemical with this ketchup.
Now, I can come back and add in more fresh peroxide and mix it up, but you will see streaks
between the old and the new.
The trouble is with the peroxide, both the old and new look exactly the same to the eye
so it's hard to make sure it is mixed up properly.
Well, what was supposed to be a single video ended up turning into a two parter.
And now, it's going to turn into a three parter because, again, this is taking longer
than anticipated and I really wanted to spend some time showing you what you can do with
an Osborne and talking a little about CP/M and the history of these machines and whatnot,
and so I've decided to split that off into a 3rd episode.
And no, it's not some episode far into the future that I might make, I'm actually working
on it right now.
So, just stick around a few days for that and thanks for watching!
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