Hard rubber conditioner

[Windsong]

Since hard rubber is technically a wood-gum  (reformulated, melted and molded), I suspect it may be slightly porous. Over time and kept in unfavorable temps, can become brittle, and I am wondering if there are conditioners that anyone knows of that may be used to strengthen it, like oils do for wood?  Most of my hard rubber clarinets are in fine shape, but a new acquisition has the beginnings of mild checking in the barrel and the bell sockets, and I want to mitigate this condition if at all possible.

[mechanic]

There are a number of products out there that are for cleaning and rejuvenating the hard rubber platens in dot matrix printers.  MG Chemicals 408A is one.  I have not tried any of the ones available today, but the ones that were available back in 2000 worked great, but were so toxic that looking at the bottle could kill ya.

[LarryS]

I don't think rubber is porous. Its structure is drastically changed during processing.

[windydankoff]

I also don't think there is any porosity with HR. I see no trace of absorption when cleaning with alcohol or water. Even thin CA glue doesn't absorb (though it bonds extremely well). I have lots of antique HR in which I see color fading, but never any surface cracking. Maybe your item was stored in bad conditions or was made from a troubled batch of material.

A rubber treatment for printer rollers would be intended to restore its paper-grabbing quality. Doesn't sound appropriate to an instrument.

[Windsong]

There are a number of products out there that are for cleaning and rejuvenating the hard rubber platens in dot matrix printers.  MG Chemicals 408A is one.  I have not tried any of the ones available today, but the ones that were available back in 2000 worked great, but were so toxic that looking at the bottle could kill ya.

Hah!  Well, Thanks for that.  I very well may try that just after being diagnosed with a terminal illness!   

[Windsong]

I don't think rubber is porous. Its structure is drastically changed during processing.
AND
I also don't think there is any porosity with HR. I see no trace of absorption when cleaning with alcohol or water. Even thin CA glue doesn't absorb (though it bonds extremely well). I have lots of antique HR in which I see color fading, but never any surface cracking. Maybe your item was stored in bad conditions or was made from a troubled batch of material./quote]

Good points.  The softeners may be the only way to go, as Mechanic suggests, but in diluted (less toxic) form, so as to add pliability, but not stickyness or actual softenening characteristics.  Until such a time, I will have to exercise extreme care, both in handling and in exposure to temperature extremes..

[GrumpyMiddleAgedMan]

I made a big booboo when I was messng with a conn director. I washed it in hot water with soap, water was foul smelling and brown after from the sulfer. Needless to say it dried out the outter layer, it was dry and slightly crackled.
I looked online for restoration solutions but didn't really find much but recommendations. One involves using glycerine. So I put on a nice thick slathering of vegetable glycerine and hit it with a heatgun to open up any pores there might be. Nothing too hot just a good warming up. It seems to have rehydrated the outside layer and reversed some of the damage.
When I think about it, it makes some sense. Glycerine is basically vegetable sap, and rubber is tree sap. At the very least it seems to serve as some sort of protection. I think it is also more preferably solution than using chemicals.

[Windsong]

That is a fine idea, Grumpy.  I appreciate the tip.

[Dibbs]

Glycerine isn't "vegetable sap." It's a bi-product of making soap from animal fat or vegetable oil.  It is certainly a chemical.

[GrumpyMiddleAgedMan]

OK, I was wrong about it being plant sap, I didn't exactly look into what I was just took that I was reading at face value. Its not exactly a chemical either.
"Glycerin is a sugar alcohol derived from animal products, plants or petroleum.
Vegetable glycerin is the variant made from plant oils. It is said to have been accidentally discovered more than two centuries ago by heating a mixture of olive oil and lead monoxide."
https://www.healthline.com/nutrition/vegetable-glycerin#what-it-is
It is relatively safe from what I read here and it did do what I needed it to do in this case.

[Dibbs]

So what, in your opinion, constitutes a chemical?

[GrumpyMiddleAgedMan]

Dictionary, any substance used in or resulting from a reaction involving changes to atoms or molecules, esp one derived artificially for practical use .
So technically you would be correct.  It is formed naturally then separated by other means. The base is still created by a natural process as opposed to being say combined in a test tube. In a common sense usage I would not consider it to be on the same level as say cyanide or Ammonia. I would think most people associate chemicals with harmful substances. Vegetable glycerine, unless you are allergic to the source plant, is basically harmless. It is not a bi-product so much but an adative to moisturizes, soaps, beauty products, food etc.
I would.think this would be a preferable option to the previously mentioned MG Chemicals 408A or something else of that sort.

[windydankoff]

Grumpy - you wrote "...  it did do what I needed it to do in this case."

Do you have before/after photos? or can you describe the effect it had? Did it help correct discoloration?

[GrumpyMiddleAgedMan]

No, I didn't take any pics of the damage I did to it after I donked it up.  I can try to describe it.
Problem was after washing it with the hot water and soap was the outside was dry, you could feel and see it. It had a kind of crackle look. It wasn't so much a discoloration as it was a drying of the rubber. I'll put received condition and current pics when I can take a new one.
I did try dying a pruefer I have, it must have been in a window or something with the case open because it is on one side. Tried calligraphy ink but it didn't penetrate, water based. I don't think sharpie worked either.

[Dibbs]

Dictionary, any substance used in or resulting from a reaction involving changes to atoms or molecules, esp one derived artificially for practical use .
So technically you would be correct.  It is formed naturally then separated by other means. The base is still created by a natural process as opposed to being say combined in a test tube. In a common sense usage I would not consider it to be on the same level as say cyanide or Ammonia. I would think most people associate chemicals with harmful substances. Vegetable glycerine, unless you are allergic to the source plant, is basically harmless. It is not a bi-product so much but an adative to moisturizes, soaps, beauty products, food etc.
I would.think this would be a preferable option to the previously mentioned MG Chemicals 408A or something else of that sort.

Glycerine is not formed naturally.  It is made by a chemical reaction called saponification that also makes soap.  It's also a waste product in the making of bio-diesel and it can be made completely synthetically from propylene.

However it is made, it is exactly the same substance whether from animal or vegetable sources.

The idea that chemistry only covers harmful substances is laughable.