how to make a 4" hole?

[dirkdaddy]

I am trying to exhaust into my attic and I was wondering how one goes about drilling a 4" hole in a wall. I own a drill but thats about it when it comes to power tools. I'm no carpenter so I am at a loss as what to do. Anyone care to explain what it will take? The entrance to the attic has a removable door/cover I can remove to drill and make the process easier. I think I read a thread here once with a pictured tutorial or explanation as to how someone did it but I can't find it. I assume you start out with a compass and draw a 4" circle but after that I don't really know what to do.

 

[who me]

either a 4 inch hole saw or a compass and a jigsaw

 

[Murphy]

A Jigsaw to cut a 4"hole in sheet rock?
get a key hole saw.......or you can go ghetto and use a course tooth steak knife. Go to the HVAC isle in home depot and get a "4" starter collar". It's a collar that has "fingers" that you just bend over to secure it and then you have a mounting point for the duct......go there and ask, they'll show you and it will help you a lot with this give you a very clean, finished look. Make sure you go in the attic and cut down, if your'e not real handy, you may misplace your hole and hit a joist, just trying to help you out. If you want, pm me and I can take a pic of my duct for you so you can see it.

 

[Bumble Buddy]

Make sure you don't drill/cut into any electrical lines, water pipes, gas pipes, wood supporting joists, etc...

You can start by using one of the 4" diameter starter collars that was mentioned for a guide, draw a pencil line around it. Drill a hole near the perimeter large enough to get your saw blade into, the type of saw will depend on what you are cutting through, you could use a steak knife as was mentioned for drywall, a razor knife will also work for drywall. A keyhole type saw (can be found in drywall section of hardware stores) will work for wood lath but it may take some work, fine teeth are better. Caulk or use construction adhesive around the starter collar when you are done.

 

[petemoss]

For a really smooth hole, nothing beats this Dremel with a circle cutting attachment. When I was doing DWC with plastic tubs, I tried using a utility knife, a drywall hole saw, and a jigsaw but just couldn't get a smooth hole. This hole cutter is the best I've used.

 

[hoosierdaddy]

At Home dePot, in the drywall tools section (next to the sheet rock) they have a small tool that is to cut holes in drywall. It is about $12 and will do the 6" hole perfectly in drywall. Basically a small compass with a cutting wheel.
You can also buy, in the tools section, a 6" cutter that is made as a recessed light kit. It is a drill held hole saw, but has only an abrasive type cutter that is only good for drywall and light stuff. I think this hole kit is about $25-$30
They also have a full on 6" hole saw, w/arbor to fit your drill, that will run about $30-$35

If you plan on any sort of cab building, I suggest spending the money on the full on hole saw. The other options will not work real easy with anything but soft drywall.
The regular hole say will make life really simple.

EDIT:
OK...4" the above options are available in the 4" also, accept for the recessed light kit.

 

[dirkdaddy]

thanks for the suggestions guys. I am making my way to home depot sometime today. I'll check out what they got. there is also some particle board I need to make a hole through. would a 4" hole saw to go on my drill work for that?

 

[hoosierdaddy]

yes...

 

[Bumble Buddy]

Yeah the 4" hole saw with arbor to fit in your drill (usually separate purchases) would be great, I think they are pretty costly though at that size... An electric jig saw is also a good option for cutting 4" holes in plywood/particleboard and the like.

I had to make some 6" vent holes for my closet that has drywall construciton; I cut some rectangular pieces of OSB (similar to plywood) and then cut the vent holes in those using a jig saw, they came out nice and neat, the starter collars fit right in. I used some short wood screws in every 3rd tab of the starter collar for extra security, then caulked around it, then screwed the OSB pieces into the wall studs and used drywall joint compound and drywall tape to finish the edges, nice and neat and airtight.

 

[AinSophAur]

keyhole saw or a serrated kitchen knife

 

[fumancu]

Nail in the center.Another one on the right size string.