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I have a little bit of trouble with the pilot bit in the hole saw mandrel when I use big hole saws to cut 5 and 6 inch recessed light holes in old work drywall. Before the holesaw has a sufficient groove cut in the drywall, the pilot bit starts to wallow out the pilot hole and it makes it hard for the saw to "track" nice. To solve this, I've started to just drill the pilot hole first with a seperate drill, and then replace the pilot bit in a dedicated mandrel with a piece of smooth 1/4" rod. It's solved the problem entirely, and I've never had better looking holes in drywall.
 

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;) You can also use an aircraft or "phone installer" type bit that has about an inch of flutes then a smooth shaft. Cut to length so the flutes clear the drywall before the cutter hits the surface. If you use jobber length bits and have a sharpener a broken bit can be re-habbed for cutter duty as well.


Either way makes a world of difference.:thumbsup:
 

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I really don't use hole saws for recessed, but I have been doing this for years with my hole saws.
That is one the most frustrating things when using one.



Here's another tip, although pretty common these days:

When drilling 1/2 & 3/4 conduit hole saws (7/8" & 1 1/8"), put a big 1/4" fender washer between the saw and the material. This way when the pilot bit goes through if you can hold it back the teeth do not "grab" the material and break the pilot bit. The washer just spins. :thumbsup:


Also:
This stuff is AMAZING to me. Use Lenox cutting oil!!! This stuff is great!
It comes in small squirt bottles and is usually right near the holes saws on the rack. :thumbsup:
 

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For the 3/4" hole saw I have been using a actual 1" 0.d. hole saw instead of the 1 1/8th. those 3/4" connectors fit in there real tight! It's so nice. As for the recess light hole saws, I use my skinny flat head for my starter hole. and a longer than normal 1/4" bit when it time for the hole saw, and of course my half a basketball between the drill and the hole saw bit. bk
 

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Usually for a buck more you can get tungsten carbide pilot bits that hold up a lot better with sheetrock and especially plaster - which is basically cement. I use an adjustable hole cutter from holepro.com and it has double tungsten carbide blades that cut great through sheetrock and even button board. I used the high speed steel blades that also came in the kit to cut 18 holes in 5/8" T&G for light cans and was done in under an hour. With plaster I used to worry about cracking it when using a saber saw and going through a blade per hole. With the hole pro cutter it get through a lot more holes with the blades and no more worries about delaminating the plaster. cheers
 

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I have a little bit of trouble with the pilot bit in the hole saw mandrel when I use big hole saws to cut 5 and 6 inch recessed light holes in old work drywall. Before the holesaw has a sufficient groove cut in the drywall, the pilot bit starts to wallow out the pilot hole and it makes it hard for the saw to "track" nice. To solve this, I've started to just drill the pilot hole first with a seperate drill, and then replace the pilot bit in a dedicated mandrel with a piece of smooth 1/4" rod. It's solved the problem entirely, and I've never had better looking holes in drywall.
I have been using that technique on sheetmetal for a long time for hole saws, it makes a huge difference.
 

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I use pilot bits on all of my hole saws that are long enough so I can just flip them over after the hole is started. The pilot retainer screw has a rounded base that holds snuggly in the flutes of the pilot bit without damaging them.
When using the Hole-Pro type cutter on the other hand, it cuts so quickly in drywall, that there is no time or need to reverse the pilot bit.
 

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I use a drywall circle cutter to score the drywall,then use a drywall saw.Never mastererd my Rotozip enough.

I don't trust a rotozip in my hand upside down and dust flying. Last cans I did were in a 3/4" thick faux stone soffitt, had the installers cut the holes for us.
 

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Wow you guys have the right tools for the job! I find myself reduced to bending ceiling wires to the radius of the circle, tracing out the hole, and drywall-sawing it.

You have heard of that new fangled circle maker thingy called a compass? It makes them perfectly round and you can even tune it in to a center mark pretty quick.
 

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You have heard of that new fangled circle maker thingy called a compass? It makes them perfectly round and you can even tune it in to a center mark pretty quick.
Why, yes I have. I sure don't remember seeing such a thing on my tool list. You will notice from my last post that I know there are hundreds of available hole making options, but none have been made available to me on the job.
 

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Why, yes I have. I sure don't remember seeing such a thing on my tool list. You will notice from my last post that I know there are hundreds of available hole making options, but none have been made available to me on the job.
???

None made available to you?

A piece of cardboard, 2 holes and a pencil is a compass.
 

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I'm stuck with two nails and a scrap of 14 wire.:laughing:


Whatever it takes, I'd be damned if I was gonna try and make a circle out of ceiling wire. I would make a compass from anything available.
 
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