What is a good way to cut a whole for a dryer vent though steel siding? The siding is double 4″ so the hole will have to be over one of the laps. I will place the vent so it be in one piece of siding, so I don’t have to cut the upper or lower part of the siding where it joins the next piece of siding. Can I use my 4 1/8 inch hole saw? Or will the lap in the middle of the piece of siding cause me trouble? I have read on this site about using a 4″ grinder for cutting strait lines, but I don’t think that would work good for a small circle. I could cut it with my red handled tin snips if the siding wasn’t on the house, but it is. Thanks for you help.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Listeners write in about haunted pipes and building-science tomes, and they ask questions about roof venting and roof leaks.
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
If it's heavy guage steel, you could mark the hole, and then take off the affected pieces. Cut them on a bandsaw with a metal cutting blade. After the hole is cut in the siding, re-assemble the pieces.
drill a hole and use a metal cutting jigsaw blade?
A good pair of aviation snips should do it.
Dan, I like the idea of cutting the whole with my red handle aviation tin snip, but have you done this while the siding is on the house?
4LORN1, I appreciate the info on the hole saw technique, I like the idea of replacing the bit with rod stock after. Just use a regular bit to drill the pilot hole and keep the rod stock in the whole saw. Maybe put a point on the end of the rod stock. No more cursing broken bits.
I've not cut siding, but have cut other things in fairly awkward positions. Good av snips have a fairly thin blade and should be able to get behind the metal without much trouble. If there's foam behind you can compress that a bit to get some more wiggle room. A pair of offset av snips with a slight curve should do it.
I use the hole saw.
Take your time. Use the side handle on the drill. High RPMs and very light pressure. I try, when thing cooperate, to use an old, dull and worn, hole saw and run it backwards, forward slower if it doesn't cut otherwise, to get the kerf started. Also helps to drill the starting hole without the hole saw installed.
This prevents the problem of the drill bit breaking through and, because it is so hard to reverse the forward pressure fast enough, the hole saw digging in. This can easily damage a wrist and the saw often goes sideways breaking the drill bit and scarring the work.
Get the quarter-inch hole in before mounting the hole saw. It is also easier to see the spot without the hole saw in the way. Replacing the drill bit with a solid piece of rod stock or all-thread, after the hole is drilled, is good practice with larger hole saws. Drill bits are brittle and tend to snap if the hole saw binds. Suddenly losing the stabilizing influence of the center bore can allow the saw to run rampant.