A E & list, Hoppe's ingredients: INGREDIENTS NAME CAS NUMBER CONCENTRATION BY % VOLUME Severely Hydrotreated Heavy Naphthenic Petroleum Oil 64742-52-5 >85% Polyalpha-olefin 66070-54-0 <10% Proprietary Additive Proprietary <10% Possibly A E chose to use this having heard of the use of ballistol, which has been used in Europe in lubricating action parts. It's also a component of Mother Goose's Goose Juice. >From Wikipedia: Ballistol (meaning 'Ballistic Oil') is a <a href="http://en.wikipedia.org/wiki/Mineral_oil" title="Mineral oil" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">mineral oil</a>-based chemical which advertises that it has many uses. It was originally intended for cleaning, lubricating, and protecting <a href="http://en.wikipedia.org/wiki/Firearms" title="Firearms" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">firearms</a>. The product originated from <a href="http://en.wikipedia.org/wiki/Germany" title="Germany" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">Germany</a> before <a href="http://en.wikipedia.org/wiki/World_War_2" title="World War 2" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">World War 2</a>, after the military requested an 'all-around' oil and cleaner for their rifles and equipment. The chemical is a yellowish clear liquid with a consistency expected of a light oil. However, when it comes in contact with water it <a href="http://en.wikipedia.org/wiki/Emulsion" title="Emulsion" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">emulsifies</a>, becoming a thick creamy white substance. It has a sweet and mildly pungent smell similar to black <a href="http://en.wikipedia.org/wiki/Licorice" title="Licorice" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">licorice</a>. It is distributed in liquid and <a href="http://en.wikipedia.org/wiki/Aerosol" title="Aerosol" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">aerosol</a> forms. The aerosol uses <a href="http://en.wikipedia.org/wiki/Butane" title="Butane" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">butane</a> or <a href="http://en.wikipedia.org/wiki/Propane" title="Propane" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">propane</a> as a <a href="http://en.wikipedia.org/wiki/Propellant" title="Propellant" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">propellant</a>. One of its selling points is that it is not <a href="http://en.wikipedia.org/wiki/Petro-chemical" title="Petro-chemical" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">petro-chemical</a> based, and uses biodegradable ingredients. It also advertises it has no <a href="http://en.wikipedia.org/wiki/Carcinogen" title="Carcinogen" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">carcinogens</a>. Some other similar chemicals contain petro-chemicals which can pollute the environment if improperly handled, and can damage the 'seasoning' developed on the bore of a black-powder gun. <a name="11aeb79a1646b57d_Ingredients" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial"></a> <h2 style="color:black;background-color:initial;font-weight:normal;margin-top:0px;margin-right:0px;margin-left:0px;padding-top:0.5em;padding-bottom:0.17em;border-bottom-width:1px;border-bottom-style:solid;border-bottom-color:rgb(170, 170, 170);font-size:150%;margin-bottom:0.6em"> [<a href="http://en.wikipedia.org/w/index.php?title=Ballistol&action=edit&section=1" title="Edit section: Ingredients" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">edit</a>]Ingredients</h2> (according to a specification from December 2002)<ul style="line-height:1.5em;list-style-type:square;margin-top:0.3em;margin-right:0px;margin-bottom:0px;margin-left:1.5em;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px"> <li style="margin-bottom:0.1em">pharmaceutical <a href="http://en.wikipedia.org/wiki/White_oil" title="White oil" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">White oil</a>: CAS RN 8042-47-5</li> <li style="margin-bottom:0.1em"><a href="http://en.wikipedia.org/wiki/Oleic_acid" title="Oleic acid" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">Oleic acid</a>: CAS RN 112-80-1</li> <li style="margin-bottom:0.1em">C-5 alcohols: CAS RN 78-83-1; CAS RN 137-32-6; CAS RN 100-51-6</li><li style="margin-bottom:0.1em">different essential oils to perfume Ballistol</li></ul> <a name="11aeb79a1646b57d_References" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial"></a> <h2 style="color:black;background-color:initial;font-weight:normal;margin-top:0px;margin-right:0px;margin-left:0px;padding-top:0.5em;padding-bottom:0.17em;border-bottom-width:1px;border-bottom-style:solid;border-bottom-color:rgb(170, 170, 170);font-size:150%;margin-bottom:0.6em"> [<a href="http://en.wikipedia.org/w/index.php?title=Ballistol&action=edit&section=2" title="Edit section: References" style="text-decoration:none;color:rgb(0, 43, 184);background-color:initial" target="_blank">edit</a>]</h2>   As someone has already noted, WD-40 is a lubricant which was used by piano technicians in an earlier era; it loosened things up for a while but eventually got gummy, caused parts to freeze up, and soaked into the wood as well -- essentially ruining everything it came into contact with. It's appropriate for use on metal parts. Patrick Draine <div class="gmail_quote">On Thu, Jul 3, 2008 at 12:21 PM, A E <<a href="mailto:eve_ane@hotmail.co.uk" target="_blank">eve_ane@hotmail.co.uk</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div> Ive used the lube for guns for years now and it worked only marvels in my piano, its only thing that keeps it functioning comfortably...   Alicia</div></blockquote></div>