Electrical box through metal garage wall

[Impala61]

What is the best way to cut a hole through the new metal wall for elec. box? And then seal it.
Thanks

 

[Nowater]

IMO cut a hole with a holesaw for a conduit that screws into the box. Seal the hole with silicone. Smaller hole than cutting a hole for the entire electrical box.

 

[EOC_Jason]

Greenlee knockouts will give you a nice clean hole... Seal with silicone caulk...

 

[Impala61]

Thanks a heap, Nowater. For some reason I hadn't even thought of that. I'll give it a try.

 

[tjdux]

Second the knockout cutter. They give much prettier holes than a drill

Sent from my SM-G900V using Tapatalk

 

[Mikeske]

Do not use silicon sealant on a metal building. The silicon will cause corrosion use a good butyl sealant.

 

[keen]

Do not use silicon sealant on a metal building. The silicon will cause corrosion use a good butyl sealant.

???!!???!!

You mean the curing compound (vinegar) in the silicone perhaps? I've been applying silicone caulk to cut edges of steel for 20 years and have never seen it cause corrosion (including pulling it off later). (where the cut edge is buried in the siliconed joint)

Certainly never seen it cause corrosion on a steel surface unless the finish itself reacted.

I have, however, seen plenty of rust under butyl sealants where the cut edges were not properly treated before hand where the installer simply expected the butyl to keep all moisture away....