I've had many decks and found that the ones that been in use, never melted their belts. Usually decks just sitting for years have belts completely melted. Personally I think it's due to non-use, rubber needs movement to stay fresh - but it's my opinion/observation only. No real info on the Net about this apart from bad manufacturing rubber curing.
So I wonder what opinion or even definitive answer someone might have.
So I wonder what opinion or even definitive answer someone might have.
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I've had belts that started to disintegrate in use, turning gooey and eventually getting loose enough they no longer work. I've also seen a few that turn into a puddle of goo after some period of disuse. This has mostly been old Japanese belt driver turntables and tape decks. The small # of belts I have encountered have generally flat and fairly wide.
Rubber belts and plastic gears may deform if are kept under constant tension/stress for prolonged amounts of time, so movement is beneficial. It also helps to ventilate away volatile compounds released from the natural decay. This web page about the care of objects made from rubber and plastic gives some facts about rubber decay factors and some simple ideas to slow them. Care of Objects Made from Rubber and Plastic - Canadian Conservation Institute (CCI) Notes 15/1 - Canada.ca
That is a good link. Seem there are many factors that can cause it. I'll just keep giving my unused decks run every month or so for few minutes. If it works I don't know but the ones I have are all still good maybe just due to this.
Besides amount (or lack of) use, rubber degrades/melts/cracks/gets gooey/disintegrates (pick one or more) .
May last more or less, but always happens, and process is irreversible.
FWIW the rubber parts of Apollo Moon mission spacesuits held at the Smithsonian Institution are fully degraded .... and we are talking NASA spec rubber 🙁
To boot this is not fresh news but I read it some 15 years ago or more, so do the Math.
May last more or less, but always happens, and process is irreversible.
FWIW the rubber parts of Apollo Moon mission spacesuits held at the Smithsonian Institution are fully degraded .... and we are talking NASA spec rubber 🙁
To boot this is not fresh news but I read it some 15 years ago or more, so do the Math.
Silicone rubber is perhaps better than butyl rubber? I heard that sulphur in city air due to heating with wood is harmful for rubber.
Pinch rollers can also suffer the same fate becoming like a blob of chewing gum.
'Rubber' keypads used on almost all remotes can often leach a gooey liquid (plasticiser). Unless you are aware of the problem it is easy to think something has been spilled in the remote. The clue is that the top of the rubber sheet is usually dry and the underside with the conductive contacts all sticky and gooey. Fortunately these always wash OK.
'Rubber' keypads used on almost all remotes can often leach a gooey liquid (plasticiser). Unless you are aware of the problem it is easy to think something has been spilled in the remote. The clue is that the top of the rubber sheet is usually dry and the underside with the conductive contacts all sticky and gooey. Fortunately these always wash OK.
I've had this happen to cables too. Especially when they stay in contact with a furniture finish for a long time.
> the rubber parts of Apollo Moon mission spacesuits held at the Smithsonian Institution are fully degraded .... and we are talking NASA spec rubber
Hmmmmm. I have a 1967 Ford tractor in the yard. While mostly steel, there are many key "rubber" parts. Yes, I am about half-way through replacing the "rubber" hoses which are degraded; but a few appear to have another 50 years in them. So do the tires, amazingly enough. Sure not "fully degraded". Maybe NASA should have got rubber from Ford?
Hmmmmm. I have a 1967 Ford tractor in the yard. While mostly steel, there are many key "rubber" parts. Yes, I am about half-way through replacing the "rubber" hoses which are degraded; but a few appear to have another 50 years in them. So do the tires, amazingly enough. Sure not "fully degraded". Maybe NASA should have got rubber from Ford?
NASA probably used some cheap 🙂 rubber because I have some 1930's radios and in some of them the rubber wire hole seals are just fine. Some gone hard tho.
Ozone crossed my mind (ok I read it in the link) but yes motors create Ozone.
My Nakamichi 500 has what looks like a silicon belt, it's perfect. Why not use that in all decks. Maybe little more cost.
Belts going bad wouldn't be such big problem but replacing them can be really hard in some decks. I just replaced both belts in Pioneer CT-X5, had to pull whole deck mechanism apart to get to it. ...And than trying to remember how it goes all back 🙂
Ozone crossed my mind (ok I read it in the link) but yes motors create Ozone.
My Nakamichi 500 has what looks like a silicon belt, it's perfect. Why not use that in all decks. Maybe little more cost.
Belts going bad wouldn't be such big problem but replacing them can be really hard in some decks. I just replaced both belts in Pioneer CT-X5, had to pull whole deck mechanism apart to get to it. ...And than trying to remember how it goes all back 🙂
I forgot to mention...if you have a remote or something that's rubberized and it becomes crazy sticky, you can just remove the rubber surface by rubbing it with methylated spirits. Last thing I've cleaned was Alesis Io2. Both front and rear are rubberized but become like a sticky tape. Washed off clean to plastic.
Methylated spirits is what I use for melted belts as well, nothing else.
Methylated spirits is what I use for melted belts as well, nothing else.
1) I didn´t read it "on the Net" but on a real and "serious" paper magazine, might have been "Science" , "Scientific American" or some other same kind, which I regularly read.
2) Yes, *some* kinds of rubber last way more, notably tires , although eventually all degrade.
As I mentioned in my "sickness list", some become gooey, some do not, so on visual inspection they "look" fine, but they crystalize and crack, or at least lose flexibility and *will* crack if flexed enough ... what didn´t happen when new.
I *think* (might be wrong) that tires and similar materials, might include other black rubber car parts such as some hoses, appear to stand longer time, at least they don´t become gooey, because of the *high* amount of filler, usually some kind of carbon black.
It being that carbon is both an absorbent of nasty chemicals and an excellent UV barrier, that might explain longer life for some car parts.
But I have seen and replaced enough cracked surface tires , hoses, belts, to know aging *is* still a problem there.
As of the NASA rubber parts, I bet they optimized them for , say, flexibility, stretchability, maybe vacuum isoltion or ultra low temperature operation (outer suit surface can reach near absolute zero if outside in the shadow), don´t think that 20 year or more durability was the main priority, given other more pressing ones.
Of course, this is just thinking aloud.
3) I think "silicone rubber", including cured RTV and such , lasts much more.
That said, although it´s elastic and used as such, don´t think it´s chemically the same as what we normally call "rubber", which was originally a natural/organic product (harvested from a tree, go figure) and which was later synthesized, but I guess keeping basic original composition, with all that implies.
Rubber degrades with time and temperature. It can either harden and fracture, or become "goo-ey" and molten. It depends on the conditions it has been stored and the type of the rubber it is.
I recently saw a very insightful video explaining the properties of rubber (focused on super-heroes with elastic powers, of all things), but it's in portuguese (try it with closed captions on):
https://www.youtube.com/watch?v=a-O0he8zR6M
As silly as the theme of the video may be, the explanation of the different kinds of rubber there are, why and how they differ, is very worth the watch.
I recently saw a very insightful video explaining the properties of rubber (focused on super-heroes with elastic powers, of all things), but it's in portuguese (try it with closed captions on):
https://www.youtube.com/watch?v=a-O0he8zR6M
As silly as the theme of the video may be, the explanation of the different kinds of rubber there are, why and how they differ, is very worth the watch.
I have also noticed ( from my collection of boomboxes) the real early ones from 60's usually have rubber that goes hard, the 80's generally just melt. But not all off course.
Today I tried to repair 80's boombox only to find not only melted belt but also one of the plastic gears (only one white one) completely disintegrated, most of it was laying at the bottom of the case in sugar size grains. First time I've seen such deterioration in boombox.
I think as time went on they just used cheaper and cheaper materials till we ended up with junk they make today. Sad news for many 80's on collectables I think.
Today I tried to repair 80's boombox only to find not only melted belt but also one of the plastic gears (only one white one) completely disintegrated, most of it was laying at the bottom of the case in sugar size grains. First time I've seen such deterioration in boombox.
I think as time went on they just used cheaper and cheaper materials till we ended up with junk they make today. Sad news for many 80's on collectables I think.
As a service engineer I used to see this all the time, particularly on old reel to reel machines, which had been unused for a number of years - the belts just melted away.
Presumably it's down to the specific type of rubber used?.
No not true ! Some butyl rubber surrounds are in Perfect condition 45 years on .. Mine for example.
My Fish pond has 25 yr old Butyl rubber liner.... Still as good as new.
I have rubber bits in my '72 beetle that are fine.
Some have deteriorated developed slight edge cracks from close to 5 decades of sun exposure..but V few in truth.
Electronic contraptions seem to be the places where rubber bits fail soon..
Too much latex inna mixture?
Could be? I have had rubber bands that can dissolve /crumble in a couple of months with UV (daylight) exposure
My Fish pond has 25 yr old Butyl rubber liner.... Still as good as new.
I have rubber bits in my '72 beetle that are fine.
Some have deteriorated developed slight edge cracks from close to 5 decades of sun exposure..but V few in truth.
Electronic contraptions seem to be the places where rubber bits fail soon..
Too much latex inna mixture?
Could be? I have had rubber bands that can dissolve /crumble in a couple of months with UV (daylight) exposure
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What degrades the rubber? Humid, Temp, Sunlight, Tension, Vibration, Dust or Odor (chemical in the air)?
When I search some vintage stuffs on Ebay, I notice some of them are nothing wrong with the rubber, but the others are completely rotten at the same age.
When I search some vintage stuffs on Ebay, I notice some of them are nothing wrong with the rubber, but the others are completely rotten at the same age.
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