Ten to 15 seconds should be adequate. It depends on the material and the exhaust volume. You always want to make sure that your exhaust is equivalent to the manufacturer’s specification, so that it’s drawing out the smoke. Typically, you shouldn’t have a problem if you have an exhaust that’s at the manufacturer’s specs. If you see smoke lingering on the inside of the machine after running a job, then you have an exhaust issue.
—Coherent
