I'm fitting an extractor fan this w/e and will need to cut two 4" holes - one in the plasterboard ceiling and one in a plastic soffit. The soffit already has a series of 3" ventilation holes and I was planning on opening one of those up to 4".
I've never used a hole-saw before. How easy are they to use and can they be used to widen an existing hole? I assume that the hole-saws fit a standard drill bit - or do I need a special attachment?
Thanks for any help Thomas
Once started it'll be OK but starting it without is skating all over the place when perched on the top of a ladder and working vertically might be interesting.
Personally I'd not bother with a hole saw for the plasterboard. Just use a compass to mark a circle, drill a small hole inside that circle and cut the rest out with a drywall saw or Stanley pruning blade in a handle.
The plastic soffit might be harder to saw with the relatively large teeth of a pruneing saw compared to the thicknes of the plastic. A junior hacksaw blade would be a better bet.
A decent 4" hole saw isn't cheap and there really is no need for one into plasterboard, unless you're making lots of holes. Simply draw out the hole, drill a pilot hole and saw with a padsaw. Will only take moments. Plastic can be done in the same way. I found a nice little padsaw with course teeth which cuts in both directions in a shed for a couple of quid. Very useful tool.
Get a scrap bit of ply/mdf and cut a hole through it with the hole saw. Fix this to the plastic with double sided tape and continue the hole through the plastic. The ply/mdf will keep the hole saw in place.
The holesaws usually need an arbour to mount on, that will also carry the pilot drill.
If you want to enlarge an existing hole you won't be able to do it with the pilot bit directly, so use the saw with a pilot bit to cut a hole in a bit of scrap plywood (or other sheet material). Then clamp that in the position you want your enlarged hole, and it will steady the holesaw until you get the hole started.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.