I'm someone who has had difficulty with synthetic valve oils. My spit seems to cause the synthetic oils (Hetmann, Yamaha, etc.) to "gunk up." I would be interested if the Houghton Horns oil is any different for people like me.
Are you saying that you do NOT get the gunk with petroleum oil? For me it seems able to show up with either.
Dave Werden (ASCAP) Euphonium Soloist, U.S. Coast Guard Band, retired Adams Artist (Adams E3)
Alliance Mouthpiece (DC3) YouTube: dwerden Facebook: davewerden Twitter: davewerden Instagram: davewerdeneuphonium