Running coax through an exterior wall

[ka1njl]

I need to run 5 lengths of LMR400 through an exterior wall so I bought one of these. DX Engineering DXE-UE-2P DX Engineering Utility Enclosure Kits | DX Engineering That enclosure has two holes for running PVC pipes through the wall to carry the feed lines. However, I can't quite figure out how to cut the holes through the wall so any suggestions will be appreciated. Both the interior and exterior walls are 3/4" pine with 5.5" of Kraft faced fiberglass insulation in between.

I am concerned about perturbing the fiberglass insulation in the wall when I drill the holes. If I drill from the inside I can force the drill bit against the face of the insulation, effectively crushing the fiberglass against the inside of the exterior wall, to minimize disruption. However, I have no good way of aligning the hole begun on the inside with the holes in the enclosure. If I drill from the outside, even if I use a small pilot bit, I am likely to spool the insulation on the bit. Does anyone have any ideas that will enable me to align the inside and outside holes without compromising the insulation?

 

[ramal121]

Carefully drill through the first wall then stop. With the drill off push the bit through insulation and press real hard against the back wall. Then run the drill in reverse for several seconds. This will not catch any insulation on the bit and seat the cutting edge on the wall. Without pulling the bit away from the far wall, flip the drill to forward and finish the deed. Use a smaller pilot bit. I have a long 1/4" that works but smaller is better.

 

[ka1njl]

Thanks ramal121. I hadn't considered running the drill in reverse to seat the bit on the far wall. I'm nearly ready to move forward on this project so I'll let you know how it turns out.

 

[ramal121]

Starting in reverse also works well when drilling through carpet in vehicles. Good luck!

 

[ka1njl]

ramal121 - great advice. I just got around to drilling the holes and I used your method. I went through the fiberglass insulation without disturbing it very much at all. Once I was through the outer wall I pushed the drill bit through the fiberglass batting and I could feel it pass through without any problems. Then I reversed the drill for a few revolutions and continued to drill through the inner wall. Overall it was easy and not very disruptive. Thanks for the great advice.