Thicker is better. It has less tendency to bend. It also has increased mass, which helps with decreasing the curling problem.
Just remember: If you put on a piece of glass, you have to pre-heat your bed to temp (90-100) and let it sit there for a while, like 10 minutes. The temp sensor is underneath the aluminum, so the temperature of the glass is not near that temperature unless it sits for awhile. Glass is an insulator, so it resists a change in temperature, but if it sits long enough it will reach equilibrium. THis also works in reverse, the glass will stay hot longer after the heater has been turned off.
So, clip on a piece of glass, heat the bed, home your Z axis and check how level your bed is while the bed is heated, then run your job. Hairspray is a big bonus too.
Chuck Bittner is a quadriplegic gamer who is petitioning the major console developers to include internal button remapping in all console games. You can help.
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