As you know you've got no safety features built into a mechanical
mod, so that's all up to you. How many amps you draw from the battery will depend on the ohms of the coil you make. Here's
an ohms law calculator. Plug in 4.2 volts for a full battery and the resistance of the coil you want to make, hit calculate and it will tell you the amps current the battery will see.
If you draw too many amps from the battery it will heat up. Get it hot enough and it will vent. Short the battery and it will vent quite quickly. Here's a
list of safe batteries for sub ohm vaping with safe amp draw limits in yellow. As long as your coil resistance is in a yellow cell for your battery, you're safe.
Your
batteries are in that list. Note that there are two different AW IMR 18650s with different amp limits. Ask away if you have any more questions!