graemefindlay
New member
Before I buy a box of pitch I wondered if anyone in/near Portsmouth has some leftover from previous projects/years?
It’s me, hi, I’m the answer it’s me!Before I buy a box of pitch I wondered if anyone in/near Portsmouth has some leftover from previous projects/years?
Pitch is solid (almost; it flows very slowly over periods of years). Tar is gloopy (technical term ) liquid. I presume @graemefindlay wants to use it to fill seams or similar, in which case he will melt the pitch and pour it into the seam where it will set. Although both result from the destructive distillation of wood, they are taken off at different stages of the process.Is it the the same product called Stockholm/pine tar? I needed a small quantity I bought about half a kilo from Decathlon horseriding department, it's sometimes used on hooves. By the look/smell of it it's the same as boatbuilding tar.
Thank youPitch is solid (almost; it flows very slowly over periods of years). Tar is gloopy (technical term ) liquid. I presume @graemefindlay wants to use it to fill seams or similar, in which case he will melt the pitch and pour it into the seam where it will set. Although both result from the destructive distillation of wood, they are taken off at different stages of the process.
55 years ago I worked for the Coal Tar Research Association, and the properties of pitch and tar were everyday matters.
Tar isn't a drying oil; it will become more viscous on exposure to air as lower molecular weight fractions evaporate preferentially but it doesn't polymerize and set like linseed oil does. I suspect that the one thin coat soaked into the wood, but the second coat couldn't and so remained on the surface. As the tar doesn't "set" it would remain sticky.Thank you
Indeed I used it (tar) on a couple of wood pieces, on one I used a thin coat and it has dried in a few days, on another one I gave two coats and a few weeks later I am still waiting for it to dry completely, it's still sticky here and there.