Cleaning tar off of parquet flooring

[foxyfeet]

Please, please does anyone know the best way to remove old tar or whatever it is, from parquet flooring blocks.?
I have to replace a section of floor where an old fireplace was and have plenty of spare blocks, but have no idea how to clean them off. I have a "volunteer" to lay them for me and then sand and varnish the floor again, but the deal is,.... I clean the 100 year old gunk off of them first.

Any advice would be very welcome.

[jakesi]

I used white spirit on mine, took a while but it was worth it.
Quick question, are you sanding down the blocks with a hand sander or a industrial sander from the hire shop?

[foxyfeet]

Thanks Jakesi
Yes I believe its an industrial sander, but as I am a million years from that stage, I dont know really.
Should I soak them in it and then just scrape them ?
Someone also suggested petrol but that sounds a bit dangerous ans smelly !

[tony1941]

Maybe irrelevant, but I recall that the best way to remove tar from car bodies is Oil of Eucalyptus. In any case, I would soak rags (old towel(?)) in the solvent and cover the worst bits first, then a sheet af plastic to prevent evaporation and leave overnight. After softening, the tar should come off with a stripping knife. Repeat for the next layer.
Good luck
Tony

[foxyfeet]

Ok, here is an update, I have thad 4 blocks soaking all day, one in white spirit and the other has eucalyptus oil in, the smell is unbelievably bad, but the black stuff is still rock hard. Maybe it isnt tar. These blocks seriously are 100 years old. What on earth would theyn have used back then ???