Resistor Based Heated bed- Help needed

Hello, my build platform is 24 in by 24 in Aluminum sheet metal 3/16 think.
I intend to epoxy the resistors to the bottem of the sheet metal and follow these plans
[reprap.org]

however, how many resistors should I use? What values? and Can i really plug that strait to 115Vac?

I do plan to have mutiple temprature switchs with a heavy duty toggle switch so i can switch from 60 degrees C to 140 degrees C and it maybe a 3way switch so because I have also seen 110 degrees suggested after the first layer of abs.

any suggestions and help would be great!!

Thanks ahead of time,
Matt

That's going to take a load of power. Nine times the power of a regular heatbed, almost 1KW. So take ohms law, work out what resistance will draw enough power, and buy enough of that value to pack the bed with one every few inches. Use a square number of resistors to make the layout and wiring simple, n parallel strings of n resistors in series will have the same resistance as the resistors used.

Please confirm if this would work

36 resistors at 1.44 to 1.5ohm
setup in 2 18 resistor series
then the 2 series paralleled

it would be 9A so i would use a 10A or 15A fuse??

now if that would work... could i really plug that into the mains without causing harm?

thanks
Matt