Custom made gutters are allowed which are not listed or "evaluated". If I had our custom gutter builder weld in some couplings to use as box hubs to screw our connectors into, why would that not be acceptable? I understand that whenever an aspect of the profession isn't directly spelled out in the code book that it becomes a grey area that can be fully governed by the AHU. However, in many cases it feels like someone wanting to make their presence known (throwing their weight around) rather than using any kind of sence. Again using my example in my first post, does anybody disagree that the connection/impedance between an emt connector and a rigid coupling would prove to be better that that between an emt connector and a "Bell box" with its coating/enamel? Also, there is nothing that states directly that a coupling cannot be used as a transition and a connector actually has a shoulder to increase surface area of contact. I believe I have heard the argument that a connector has less threads of contact when compared to rigid pipe but it is still much more overall contact than a connector with a locknut. I wish the code would simply spell out this situation so that it would be held to the same standard everywhere. The only reason the "proper" connectors are so expensive is do to their low production numbers. If everyone was using them they should drop dramatically in price.
