johnstone question

[wvbowhntr]

well i went through my first couple of pounds of rock thought i would try an old toilet tank lid.  it was pretty thick i could thin it somewhat but got really bad hinges is there any trick to keep it from hinging so bad?

[mullet]

 Grind, grind, and grind. Then set up platforms to strike. Grind the square angles off.

[leapingbare]

Johnstone is tough. your platforms and angles and the right force of your strike have to be just right or it will let you know.

[Hillbilly]

Good advice. You also need to edge it and build up a bit of a lenticular cross-section with shorter flakes before you try to run flakes across it. They tend to step on the flat surface, especially since there is a layer of glaze on the surface. The tank itself is better than the lid, and older tanks are usually much better quality than new ones.

[DanaM]

The modern cheap made in china ones are really crappy
Find an old American Standard