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Repair vs Preservation

syzygy said:
I have had a few negative surprises from long term storage...

20+ years of a cable (C64 power supply) wrapped around this and nothing else in the box showed any damage at all.
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IC corrosion - 20-30 years. Do not think it was a simple matter of the foam because other ICs were on that same foam for that length of time AND in the same plastic bin - only a few were like this but most were fine. BTW I have many ICs over 40 years old and they are completely undamaged.

View attachment 1258459

In the numismatic field, small coin packages (flips) came out made from soft pvc. They were all the rage for many years; until it turned out that the PVC leeched out of the package resulting in deposits on the coins, and, if left long enough, seriously damaging the coin. https://www.ngccoin.com/news/article/5244/NCS-coin-conservation/

Hopefully, professional curators are on top of these kinds of issues, as much as possible.
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Took me many years realize where those marks in the plastic enclosures came from, I remember when I first saw them thinking that it was done with a soldering iron, wasn't until recently that I heard about :cable burn". Still don't exactly why it happens but I figure it's a chemical reaction of some sort.
 
We had to replace miles of cable at work due to the chemical interaction between plastics. Think it was neoprene that was causing the problem.
 
Gary C said:
We had to replace miles of cable at work due to the chemical interaction between plastics. Think it was neoprene that was causing the problem.
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I realized that it was some type of chemical reaction rather than some damage caused by someone being careless when picked up a n.o.s. TI program recorder and saw that it had a couple of those indentations even though it had never been opened and saw that one of the cords that were included with the recorder was lying where the marks were. Is it something that will happen with modern cables if they are stored with other plastics or is it some chemical that used to be used once upon a time but is no longer in use today?
 
channelmaniac said:
For a machine that special, spend the time to get period correct parts for the repair. I don't have any sockets from that era as I sold them all to a guy that sells Mark 8 repros a few years back. I do have some correct types for an Apple I, but no more of the colored ones used on the Mark 8.

I might have some period correct ICs. Just ping me and let me know what you're looking for.
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Thank you. Actually, I think I might be okay. A while back, I was thinking about building my unbuilt original boards. Jon Titus himself talked me out of that, so then I started working towards building an authentic Mark-8 from all vintage parts (including PCBs using vintage PCB copperclad). So I have a fair number of 1975 or earlier parts, especially hard to find ones like the Signetics 8263s, and ceramic and plastic NOS Intel 1101s (although I won't need those here), and a bunch of others. Also rolls of soldercon sockeets. Plus whatever I stock I have generally and leftovers from my TVT project. I think I'm more afraid of what breaks as I try to get the boards apart and out for servicing really.

And also I have no documentation for the mods Grant made, so no idea how that changed the rest of the machine and if I can make it operate without some of the missing mod pieces. Definitely will be a challenge.
 
Gary C said:
Oh I agree

I detest this 'recaping' trend with a passion.

Yes, leaking and bulging electrolytic, yes Apple IICI SMT's and every 80's RIFA but to remove period components just for the doing of it annoys me.

Of course its a fine principle to have right up until an exploding capacitor takes out some hard to find components but I have only had one machine that has suffered damage during a capacitor failure and that was an easy to replace rectifier.
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Recapping is just a fad really. But I think it was born from all the issues with SMD caps in machines like the 68k macs, etc. and then just got out of hand from there.
 
mountainking said:
I understand what you are saying about the repair part of the video though I think if you do enough prep (asking technical questions here, using both posts and private messages, as well as reading up on things), write up an outline and then film a ton of the process you will be able to edit it into something that wills work without shining a light on your lack of knowledge and/or experience in the field of electronics. Really, I don't think that you will even have to show a lot of footage of you working on the computer, most of it could be you narrating stills of parts, circuit diagrams and various close ups of the guts of the computer. And besides, that part of the video/doc will be just that, one part of the video, the story of the Mark 8, Grant's story and your acquisition of such a special piece will probably take up most of the video. No doubt it will be a lot of work all around but I know it's going to be pretty awesome.


It's all apart of getting old, people and things that we think are going to be around forever slowly begin to move from this world. Mentally we are still in our 30s but the reality is that we are pushing 50 (pretty sure we aroudn the same age). Btw, is Grant Runyan still with us? I thought that he had passed but I may have misread something or just made an assumption.
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Thanks! Yeah even just filming bits of the repair process.. the problem for me is a) remembering to do it and b) then understanding enough to explain what I did. I get taken to task sometimes for not explaining in enough detail. :)

Mentally I'm still late 20s.. haha. But yeah, body not so much.

I don't think Grant is with us. He retired in 1976, so if we assume he was early 60s then, nearly 50 years later, he'd be pretty darned old. I used one of those person search things online and it came up with a Grant Runyan in Santa Barbara who was born in 1914 and died in 1984. That would mean he would have been 62 when he retired.. 70 when he died. That's kind of average for both profession and lifespan. If he was born in 1914 he'd be my great grandparents' ages, and I don't even have any grandparents left. And I doubt if he were still alive he would have parted with these anyway. When you put your name on something like that to me that means you're pretty proud of it.
 
mountainking said:
I realized that it was some type of chemical reaction rather than some damage caused by someone being careless when picked up a n.o.s. TI program recorder and saw that it had a couple of those indentations even though it had never been opened and saw that one of the cords that were included with the recorder was lying where the marks were. Is it something that will happen with modern cables if they are stored with other plastics or is it some chemical that used to be used once upon a time but is no longer in use today?
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I dont know. The replacement project was finished years ago so I dont have people to talk to, but I would be surprised if modern compounds escape totally in the next 40 years.
 
syzygy said:
I have had a few negative surprises from long term storage...

20+ years of a cable (C64 power supply) wrapped around this and nothing else in the box showed any damage at all.
View attachment 1258458
IC corrosion - 20-30 years. Do not think it was a simple matter of the foam because other ICs were on that same foam for that length of time AND in the same plastic bin - only a few were like this but most were fine. BTW I have many ICs over 40 years old and they are completely undamaged.
Click to expand...

This is caused by the plasticizers leaching out of the cable and softening the plastic shell of the device they are wrapped around. I've seen a lot of slimy cables with those leached out during the Computer Reset liquidation.


syzygy said:
View attachment 1258459

In the numismatic field, small coin packages (flips) came out made from soft pvc. They were all the rage for many years; until it turned out that the PVC leeched out of the package resulting in deposits on the coins, and, if left long enough, seriously damaging the coin. https://www.ngccoin.com/news/article/5244/NCS-coin-conservation/

Hopefully, professional curators are on top of these kinds of issues, as much as possible.
Click to expand...

TI made an incredible amount of chips with steel legs that were silver plated. Horribly made chips. Fujitsu did similar makes on custom chips for Namco on boards like Pac Man, Galaga, Dig Dug, Xevious, and many other arcade boards. GI did the same thing with millions of 9316 mask ROMs. These steel legs like to separate from the body of the chip when you pull them out of sockets. Horrible idea to lower costs.
 
This is like the old riddle:

My grandfather left me his AXE.

one day chopping wood with it the handle broke. I bought a new handle.
sometime later while using it the axe head broke. I bought a new axe head.

i replaced the Axe head and the handle, is this still my grandfathers AXE?


If you want to see the computer work then fix it, most likely you will have to replace components, and you may have to rewire it because in its last days maybe the owner was in the middle of tinkering with it and caused it to fail in some way. then the usual compromise of can you get original replacement parts from the era, will those parts even be good after 40-50 years, or document the changes and keep the original parts in a bag stored inside the computer itself for historical purpose. in the end you will have what the original builder wanted something that works and can be used.

Or stick it behind a glass cabinet never to be touched and when you are sick of looking at it sell it to the next person that will put it behind glass.
 
furball1985 said:
This is like the old riddle:

My grandfather left me his AXE.

one day chopping wood with it the handle broke. I bought a new handle.
sometime later while using it the axe head broke. I bought a new axe head.

i replaced the Axe head and the handle, is this still my grandfathers AXE?


If you want to see the computer work then fix it, most likely you will have to replace components, and you may have to rewire it because in its last days maybe the owner was in the middle of tinkering with it and caused it to fail in some way. then the usual compromise of can you get original replacement parts from the era, will those parts even be good after 40-50 years, or document the changes and keep the original parts in a bag stored inside the computer itself for historical purpose. in the end you will have what the original builder wanted something that works and can be used.

Or stick it behind a glass cabinet never to be touched and when you are sick of looking at it sell it to the next person that will put it behind glass.
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Hehe yeah the good old Ship of Theseus. In that debate, I fall firmly on the side of those who say it's no longer the same ship. And on a lot of the machines I have I don't feel like that matters, because the owner is anonymous, and I might be the third or fourth owner down the line anyway. It only gets tricky for me here when I'm dealing with two pieces that are in the historical record. I don't think swapping a few ICs with date code correct parts would be the end of the world.. it's more that I fear breaking and having to replace a lot of stuff with my own.

I think I will just clean it as well as I can, document everything and do my best to make sure it's not going to short out, replace the obviously missing chips, power up and see what it does.
 
I think I'm with the majority of you here who want to see things work so if I have to replace parts I do, but my compromise is to keep all of the original parts even when I know for certain they are defective in case the next owner, if there is one, wants to return the machine to 'museum condition' - in other words they would rather have it 100% original than working. That's not my way of doing things but I respect that other people may differ.

Depending on the age and rarity of the machine I may ultimately try to source era-appropriate parts for it but I have no qualms about fitting modern equivalents to prove that the era-appropriate parts will be worth seeking out. An example of this might be where a system originally had mask programmed PROMs which have failed and the only easy option is to replace them with pin compatible EPROMs. I would use the machine with EPROMs fitted but I would keep the failed original PROMs close by so that a future custodian can put them back in if they so wish.
 
At least people still make axe heads and axe handles, so you can show somebody what an axe does properly. If we stop making parts for these computers, then eventually I don't think we can properly show what these things can do. With the way things are made these days, these newest computers probably won't hold up for very long. So I guess if anyone helps a little, it's better than nothing. I think a little repair is going to be needed no matter what.
 
If the axe was mass produced and you keep replacing heads and handles from the same production run exactly what would be the difference? Your grandfather would not know the difference by looking at it or by using it.

In the days before mass production where a pattern was not used, and parts were not interchangeable then you would have a problem. Computers came along way after mass productions and anything you can't just replace with an equivalent can probably be machined, 3d printed, or just reverse engineered to work.

There will always be hardware guys who want the machine to be as it left the factory (or garage) and those who just want to run the software as it was supposed to run. Then there are people who want working hardware with original software often times using newer tech to make storage transfers easier. If a computer was built with card slots or breadboard areas for future expansion you might as well use them.
 
falter said:
Do you restore it, knowing to do so involves substantial disassembly and potentially undoing some of the original owners' work? Or do you preserve it as is so it can go unmolested to a museum or something one day?
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You restore it, because the original owner would have done the same thing. It was period-appropriate to repair systems you used, instead of treating them as disposable.

If you're worried about losing history, make a video documenting the work you're undoing. The video can serve as a record of what work was originally done, and what work was done to it at the time of the video to restore the unit to functionality.

Another way of phrasing your original question is "Is it more important to preserve items, or history?" If the former, you restore the item. If the latter, you take tons of pictures and then bury the item in a time capsule. But if you shoot a video showing what you did, you can do both.
 
Trixter said:
You restore it, because the original owner would have done the same thing. It was period-appropriate to repair systems you used, instead of treating them as disposable.

If you're worried about losing history, make a video documenting the work you're undoing. The video can serve as a record of what work was originally done, and what work was done to it at the time of the video to restore the unit to functionality.

Another way of phrasing your original question is "Is it more important to preserve items, or history?" If the former, you restore the item. If the latter, you take tons of pictures and then bury the item in a time capsule. But if you shoot a video showing what you did, you can do both.
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I actually did film something - ended up being about 2 hours of fairly granular going over both machines, some background on them and the owner. Youtube will probably tank it, but I want to do decent videos that could be considered useful reference material one day.

I suppose one other consideration we didn't talk about was value - there are some machines that have real monetary value and I know some examples where the owners really don't want to mess with originality (ie. Apple-1). I've seen it affect prices on other machines like the Altair, so I suppose that's a consideration if you want to make your lies to your wife about your machines not being a total waste of money somewhat true. :)
 
ScanDisk said:
I'm fine with yellowing and wear and tear, but if something if filthy, or overly rusted, that is a completely different story.
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Those are the best kind to get cheap and work your magic on! I like the ugly ones if the price is really low if not free. I have a pretty large collection. If I get a machine and its working. Well I play with it for a bit and it gets put on a shelf. If I have to repair it on the other hand, then I sort of develop a relationship with it. I get to know its workings better and then I have a connection with it. I feel that way about most of my repairs. The working ones.. Well I simply own them.. I have no real connection to them.
 
You know, with plastics dissolving over time, I wonder how long before we get a spray-on surface and we'll just spray the surface with this material, and the plastic will decay and disappear and leave it's "imprint" as a thin veneer on the new clear surface that was added later, and then be backfilled for strength, so that these museum artifacts can last forever - or closer to forever than plastic will.. Just a visual reminder of what things once looked like... And smaller items that are only for viewing might just be locked in solid materials forever after being rendered internally inert so the parts won't react with each other.


Trixter said:
If you're worried about losing history, make a video documenting the work you're undoing. The video can serve as a record of what work was originally done, and what work was done to it at the time of the video to restore the unit to functionality.
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I also am in two minds about what should and should not be removed. My zx80 has a zx81 conversion - a full daughter board and all the extras, and it actually still works - no repair needed. So I left it all there, including the composite output mod ( though it has a weird bayonet fitting halfware between BNC and Micro BNC that I can't find a plug for ) and I have all the original conversion documentation, schematics, kit contents etc. The original zx80 is all there, and could be restored to a zx80 - which I love, because it was the first computer I ever got to program on - but I'm leaving it as a zx81 convert because that's what they did back then. Sure, I'd love one that looks like an original zx80 as well, but there's nothing wrong with an original zx80 that was converted into a zx81 either.
( For those who aren't familiar, it looks like a zx80 with a zx81 keyboard overlay, which literally just sits on top of the zx80 keyboard. The rest of the mods are all "daughterboard" mods with wires to the original PCB )
 
Hey Falter. Great Job on the Video. Cant wait for the followup. I really want to know how much you paid. its killing me not knowing! What a find....
 
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