Drilling Holes for EZ-Lok Thread Inserts

[Mike Goetzke]

I have a cheese cutting set project that needs the subject holes drilled (1/4-20). I also need to make a mandrel. I have a chuck with MT that I'm using in the tailstock but my twist drill bits don't want to drill straight. Would a spur point, spade, or forstner bit work best? I have also seen some use center drill bits to start the hole. (I trying to be economical and not buy the $12 mandrel from Rockler :D ).

Thanks,

Mike

[Marvin Hasenak]

I would use a jobber bit to dill the hole after starting it with a center bit. As to the mandrel if you have a drill chuck that fits the headstock that has drawbar, I would make a mandrel out of a 1/4-20 bolt, cut of the head and add some washers to the bolt after it is chucked up. If you have a collet chuck, I would use that before the drill chuck.

[John K Jordan]

I would use a jobber bit to dill the hole after starting it with a center bit. As to the mandrel if you have a drill chuck that fits the headstock that has drawbar, I would make a mandrel out of a 1/4-20 bolt, cut of the head and add some washers to the bolt after it is chucked up. If you have a collet chuck, I would use that before the drill chuck.

I agree, I always start with either a machinist's center drill or a spotting bit - either are stiff enough to start the hole perfectly. I keep one in a spare MT2 chuck all the time. These are cheap to buy (I got some from Amazon)

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For drilling the hole I like to use Screw Machine bits. These are shorter and stiffer than jobber's length bits although a set is typically more expensive. If I have a along hole I'll drill it part way with the short bit then finish with the longer. I prefer standard twist drill bits.

Another thing that helps me is to eliminate the Jacobs chuck in the tailstock! I found a deal with incredible prices on taper shank drills. The MT2 tapers are held directly in the tailstock and the smaller ones with an adapter. What I like about these is there is less extension from the tailstock and less that can go wrong.

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JKJ

[Sid Matheny]

I have a couple of sets of center drills I use. Makes a big difference for me.

[Tom Giacomo]

I got a set of center drills from HF for $6 and they work fine.

[Mike Goetzke]

Thanks for the replies. Think I will start with a set of center drills from HF.

Mike