Vintage Rubber Feet + Bare Wood = Very Bad?

[dcr]

I had two pre-ADB keyboards with rubber feet in perfect shape.  Now, I only have one with rubber feet in perfect shape.

One was a donor model.  It had a missing key, so I removed a second key from it to repair the other one which had a broken and/or missing key.  The other day, I was looking through some of these old Mac peripherals and discovered this donor keyboard was stuck to the shelf it was on.  Upon getting it loose, I found all four feet had melted into the wood shelf it had been sitting on.  This was an unfinished wood shelf.

I immediately checked the second keyboard which was kept in a metal cabinet.  I figured if the feet melted on the wood shelf, the feet sitting on metal would surely be a mess as well.  But that one was fine.  (Although I am now storing it face down just in case.)

I'm not sure why the feet would become a gooey mess on wood but not metal.  Both keyboards were in the same room.  The keyboard with the melted feet was closer to a window.  I thought perhaps it got more sun than I anticipated, but I have some compact Macs in the same location except placed where they would get more sun.  (Not on purpose--it just happened to be the only storage space available.)  I'll have to check on a sunny day, but I don't believe they are in direct sunlight.  Regardless, the feet on the compact Macs, which I would presume to be the same material, are fine.  But they are sitting on cardboard and not directly on bare wood.

Has anyone else encountered the same problem?

Second question, is there a good source for replacement feet?  I have grey rubber I can cut to size if need be, but if there is a source for actual matching feet that would be better, especially for a third keyboard I have that only has two good feet so needs two more for balance.

 

[joethezombie]

I had this same thing happen with my IIfx.  After sitting on the wood table overnight, I went to move it and the feets had half-liquified leaving a horrendous grey/white streak across the table.  I can only guess that the rubber is breaking down much like the seals in the Quantum HDDs.

I haven't been able to find any exact replacements.  3M makes some similarly sized feets available in clear or black.  Not sure what I'm going to do... probably get some clear ones for the time being so I don't damage the bottom of the IIfx case or what I am sitting it on.

 

[Danamania]

I had similar - a color display sitting on MDF for years, and it was fine. No marks left on it. I pulled it out while setting up a 6360, and sat it on a satin-coated set of drawers. Overnight it turned to a sticky awful liquid. 

I can only presume that age had made it sensitive to whatever is in the coating of the wood on the top of the drawers, and the rubber was stable until it came into contact with that. Then it turned to goo.

 

[Scott Baret]

I can do one worse.

This past fall, I got an ADB keyboard and one of the feet was a little worn. I left it in my car for a day before taking it in. The foot melted on the seat of my car.

It took a good hour and lots of elbow grease (and Turtle Wax interior cleaner) to get that mark off.

Beware of the feet on LCs, too...they can get wonky over time.

 

[TjLaZer]

It's not the wood, the rubber stops are 30 years old and decaying and they get gooey.  Happened on my Atari computers too.  PITA to remove!