Jump to content

A Bone To Pick


Recommended Posts

While at the market selecting marrowbones for making soup, I was also inspecting them with an eye to their potential usefulness in making "the bones", such as I use for playing percussion. And it occurred to me to wonder what sort of bone was used to make all those old concertina buttons.

 

In some earlier Topics -- particularly here and here -- there has been some excellent information about the differences in leathers... not just which animal, but which part of the animal and even the orientation of the grain, and how this relates to characteristics appropriate to different uses. (Rich Morse has been an especially knowledgeable and helpful contributor.)

 

So I wonder, is/was selecting the right bone for buttons equally specialized?

Link to comment
Share on other sites

So I wonder, is/was selecting the right bone for buttons equally specialized?

Jim,

 

Whilst leather has not been surpassed as a material for making bellows, bone has not been used for making concertina buttons since the late 1920's, when Lachenal's started to use Erinoid (an early Casein plastic), followed by both Wheatstone's and Crabb's. In more recent times, Delrin seems to have become more the material of choice. So I fear you may find little, or no practical experience of the subject today.

 

I must look in my 19th century Holtzapfel books on turning, and see what he has to say on types of bone (not a pleasant material to turn), though I believe that plenty of those buttons described today as "bone" are actually ivory, and plenty of those described in the past as "ivory" were actually bone ... :huh:

Link to comment
Share on other sites

Whilst on this subject I have often wondered if nylon would be a better product for buttons.It is very hard wearing but not brittle.The milky white finish may put some people off ,but it is flexible and needs no lubrication.Or is Delrin a derivative of Nylon?.

Al

Link to comment
Share on other sites

I don't know about the relationship delrin has to ivory, if any. However, Delrin machines better and can be polished. Nylon has the tendency to melt when being cut by machine. As far as strength is concerned, for all practical purposes, Delrin buttons are unbreakable, can be polished nicely and will last forever. :)

Link to comment
Share on other sites

I enquired some time ago with a knife maker about the source of bone for buttons and was told, anything big enough. Modern cow bones from an abbatoir are apparently not very big because we kill and eat them earlier than they used to. In the old days horse would have been a consistent source, and they are large enough. You have to boil the bones to get the softer residue off, very smelly, and it also stinks when it is machined.

 

Delrin (or Acetal) is a form of formaldehyde. I think it is called formaldehyde dimethylacetal. You need to make sure it is not heated excessively as formaldehyde is an animal carcinogen. Easy to turn, I find them slightly slippery when the weather is warm, maybe I polished mine too much. In the end the only thing wrong with Delrin buttons is they have an image problem; we associate plastic with all the connotations of cheaper...

 

Chris

Link to comment
Share on other sites

... and it also stinks when it is machined.

So much so that, I am told, you need to change your clothes and take a shower after turning it !

 

 

Delrin (or Acetal)  is a form of formaldehyde. I think it is called formaldehyde dimethylacetal. You need to make sure it is not heated excessively as formaldehyde is an animal carcinogen.

Whereas Casein is the protein in milk, hardened by immersion in formaldehyde. Erinoid (the variety used by the old concertina makers) was so-named because it was developed by the Condensed Milk Co. of Ireland (a.k.a. "Erin"), though then manufactured in Stroud, Gloucestershire.

 

 

Easy to turn, I find them slightly slippery when the weather is warm, maybe I polished mine too much.

Though it would make it all the better for harpsichord plectra, which is what I first heard of Delrin for. It lasts much longer than quills !

Link to comment
Share on other sites

... and it also stinks when it is machined.

So much so that, I am told, you need to change your clothes and take a shower after turning it !

Seems an exaggeration to me. I've shaped bones (slabs of cow bone as a rhythm instrument) on a belt sander, and while the odor is distinctive and strong, it didn't "come home with me", nor did other workers 10 meters away complain about the odor while I was working.

Link to comment
Share on other sites

I SEEM TO REMEMBER A COMMENT ABOUT CAMEL BONE AS IT HAS SMALL BLACK FLECKS. IF YOU CLEAN THE BLACK BUTTONS ON TREBLES THEY ARE USUALLY FAIRLY GROTTY IN APPEARANCE.

DELRIN IS PROBABLY THE BEST MATERIAL FOR BUTTONS . ALTHOUGH POLYCARB OR LEXAN WOULD BE OK. IF YOU MACHINE DELRIN / ACETAL AT LOW SPEEDS IT WILL NOT SMELL. IF YOU CAN GET DELRIN 2 THEN THAT SMELL OF THE LARGE TOM CAT WILL NOT BE APPARENT.

I DONT KNOW MUCH ABOUT THERMOPLASTICS AS IVE ONLY BEEN INVOLVED FOR 40 YEARS AND WE PROCESS ABOUT 800 TO 1000 TONNES A YEAR

Link to comment
Share on other sites

Well, it was the man's wife who said it !

 

Well, then you KNOW it was an exaggeration! :D

 

I once painted a motorcycle frame in the basement, resulting in some fumes leaking into the house...my wife accused me of "trying to kill the whole family"! Clearly, a feminine tendancy toward alarmist behavior!

Link to comment
Share on other sites

As to bone for buttons, Rosalie Dipper told me she won't use it because of the risk of Mad Cow

 

Is it neccesary to use a particular animal's bones? It strikes me a deal might be struck with a local vetrinarian if one isn't picky....

Link to comment
Share on other sites

Sorry but I now have a mental image of a vet looking somewhat loke a jelly-fish.

 

-------------------------------------------------------------------

 

Correct me please, but is not derin the US term for nylon??

 

Dave

Link to comment
Share on other sites

Sorry but I now have a mental image of a vet looking somewhat loke a jelly-fish.

 

NOT exactly what I meant.... I was thinking that they have to dispose of carcasses anyway....

 

My Canadian wife and her mother were confused when I was giving directions, and said to "pass the Vet's Cemetary"...The MIL thought "vetrinarians" and the wife thought "Vettes"....should have taught me phrase things properly then, I suppose.

Link to comment
Share on other sites

Correct me please, but is not derin the US term for nylon??

Dave,

 

Delrin is the brand name for an acetal resin engineering polymer, discovered by DuPont and patented by them in 1956. It is described as "a lightweight, low friction, and wear-resistant plastic capable of operating in temperatures in excess of 200 degrees Fahrenheit", and it is often marketed and used as a metal substitute.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...