Building an enclosure from scratch

I want to build my own enclosure for an electric panel consisting of a plc, terminal blocks, relays, hmi, etc....i was recently told to use pem, but i dont understand how pem works. If I install my panel to the enclosure before i put on all my electrical stuff, din rails and wire ducts, how would i put it on after?

If this does not make sense i can try to paint a better picture, but it really doesnt make much sense to me. I thought building an enclosure from scratch would be just as easy as bolting different pieces together.

can anyone clarify anything lol?
On a brighter note, happy friday!

Pem nuts, you mean?

Any panel I've ever built, I have just removed the back panel from the box, laid out the components and marked the mounting holes, drilled and tapped the back panel, screwed on the components and wireway, wired it on the bench, then installed it in the box.

Am I missing anything?

Oo-v-oO said:

Pem nuts, you mean?

Any panel I've ever built, I have just removed the back panel from the box, laid out the components and marked the mounting holes, drilled and tapped the back panel, screwed on the components and wireway, wired it on the bench, then installed it in the box.

Am I missing anything?

Click to expand...

I did mean pem nuts, and i just asked a senior engineer. he clarified things for me... this stuff is brand new to me, i thought once sheet metal had the design they would install the panel before i installed the pieces. but that clearly doesnt make sense, and i was beyond confused. the engineer will help me later choose which pem nuts to use and how to install later...thanks for everyone who read and oo-v--oo for the reply! TGIF!