# Help identify old tool



## Emrald (Mar 7, 2021)

I have what look to be drill bits but I am not sure. They are from my grandfather's tool collection.


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## Bob Bengal (Jan 2, 2021)

Guessing from the shape, they make pilot holes for screws?


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## David Nickell (Jul 6, 2020)

Emrald said:


> I have what look to be drill bits but I am not sure. They are from my grandfather's tool collection.
> View attachment 425171


Are some of those hinged? Or, just two piece but rigid?


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## Jim Frye (Aug 24, 2016)

Yes, wood screw pilot, countersink bits. The markings designate the screw size they are meant to be used for. I have a set by Craftsman given to me by a relative as a Christmas present many decades ago. The set even has a depth stop, which I don't believe I ever used. They worked rather well and the set still hangs on the tool board in my shop, although I don't use screws any more in woodworking. Since the set is still in the original packaging, perhaps my descendants will know what they were used for.


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## Onefreetexan (May 3, 2018)

I find they are very useful for drilling pilot holes for screws. I use screws for furniture instead of nails.....works better, and with there bits I can get a nice clean hole,.


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## woodnthings (Jan 24, 2009)

Jim Frye said:


> Yes, *wood screw pilot, countersink* bits. The markings designate the screw size they are meant to be used for. I have a set by Craftsman given to me by a relative as a Christmas present many decades ago. The set even has a depth stop, which I don't believe I ever used. They worked rather well and the set still hangs on the tool board in my shop, although I don't use screws any more in woodworking. Since the set is still in the original packaging, perhaps my descendants will know what they were used for.


They combine the pilot drill and the countersink into one bit, saving time eliminating changing between two different bits. The flat "washer" is the depth stop to prevent from going too far down. As with some "combination" tools they may not be as precise as the two separate bits in some materials, but will work OK in most. I have several sets, but I use a separate countersink for a "cleaner" finish for fine work. A pilot drill and the screw have a "special" relationship. Too small a drill and the wood may split. Too large a drill diameter and the threads will have no "bite" . They need to be a perfect match for best performance and that means the solid portion of the screw, minus the threads should be the same as the drill's diameter. A wood screw is a tapered conical wedge with threads, and will tend to split the wood between the long grain if not pre-drilled with a pilot hole. Sheet metal screws are not tapered and may work better in some applications.


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## Tool Agnostic (Aug 13, 2017)

I haven't seen that type before. 

I have a modern set from Rockler and use them quite often. 

They are tapered drill bits with a built-in countersinks for #6, #8, and #10 screws. There is a sleeve that fits over the drill bit with a hex drive for screwdriver bits. You can drill holes and drive the screw with one drill/driver without removing the drill.

Go to Rockler's website and search for "insty-drive countersink". There are various choices and sets, all very expensive. Wait for a sale or coupon.


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## FrankC (Aug 24, 2012)

These from Wolfcraft are the best that I have used:








Wolfcraft Tapered High Speed Steel Wood Countersink Screw Setter Set (4-Piece) 2590405


Quality results require quality tools. Quick, professional results are easy to achieve with the Wolfcraft 4-piece wood countersink screw setter set. Wolfcraft's unique design lets you work efficiently,



www.homedepot.com




No affiliation with HD, just used the image.


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## kwoodhands (May 1, 2020)

I have a set maybe two sets of those drills. My sets do not have a stop. They have the tapered flat drill, countersink and counterbore. If I recall the shanks are 1/4". I rarely use them as they are weak compared to tapered twist drill types.
Nothing is replaceable, if you break or dull the twist drill type the drill can be replaced. I think the first set was bought in 1963, probably from Sears or a local hardware store. That takes care of the bottom pics. I think that the top pics are a type of combination drill .countersink and counterbore like the bottom pics but these may be made in a home shop, not bought like the others. What is the shank made from, looks like it may be pipe, Are the pipes or solid rounds slotted to receive the cutter? Looks like it is and the maybe cutter hard soldered to the pipe

mike


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## kiwi_outdoors (Jan 15, 2020)

I had a set - they worked fine for general use.


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## JayArr (Sep 18, 2018)

I bought this a few months back and I love it. It clamps onto the bit from both sides using two screws so it ends up properly centered. The cheaper ones use a single grub screw to tighten against the side of the bit and that makes them off center which leads to them wobbling and loosening. It's also universal, you can change out the bits for different sizes of screws.



https://www.leevalley.com/en-us/shop/tools/power-tool-accessories/drill-bits/40128-adjustable-carbide-countersink?item=15J7001











Adjustable Countersink/ Multi Diameter Countersink fits drills with Dia 1/8


Adjustable Countersink/ Multi Diameter Countersink fits drills with Dia 1/8" (3.omm) to 9/32" 97.2mm)




www.dimarcanada.com


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## HicksBenedict (Aug 11, 2021)

Bob Bengal said:


> Guessing from the shape, they make pilot holes for screws?


True...


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