On 8/25/2017 12:25 PM, Scott Lurndal wrote:


Or drill two or three 3/4" holes in the back. My electronics cabinet has a number
of these with friction-fit small metal round vents.


You need more than that to vent properly. If you have one outlet equal
to the size of the hose, the velocity of the exhaust will be equal to
the velocity of the inlet. Put your hand over the outlet on the vac and
see if a couple of 3/4" holes is enough not to make back pressure.