Top 10 Forstner Bit Extension 3/8 Shank – Forstner Drill Bits

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1. Fulton

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Carpentry and Construction, Fulton 6 inch Long Forstner Bit Extension for Adding Over 5-5/8 inches of Drilling Depth to Your Forstner Bit. for Wood Turners, Furniture

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Fulton #ad - The collet outside diameter is 25/32 inch without the set screws protruding outward. The reason this is important is that as we mentioned earlier, some bits may have slightly different shank sizes. To remedy this issue we have developed a heavy duty steel extension that allows you to secure a 3/8 inch shank forstner bit into the end collet.

If you measure your bit shank and it is 3/8 inch, your bit should fit once the set screws are loosened. One of the most common uses for the forstner bit extension is for woodturners who need to bore out starter holes on larger vessels. However, the extension works exceptionally well for projects like salt shakers, pepper mills or even wood turned beverage mugs. This will help you create larger diameter starter holes or help when you need to drill in just a little further than the standard bit length will allow. Forstner bits and Machinery shown in pictures are NOT included.

The minimum size hole this extension will allow you to drill is 13/16 inch. Drilling with forstner bits to achieve a flat bottom hole or to start a deep hole turning project like on a larger vase or vessel is essentially impossible with a standard length forstner bit. Contractors use the extension when they need to bore deep holes for running cables or wires and they also use it for joining larger timbers. It is designed to be used with forstner bits only. This tolerance is very tight and designed to accept forstner bits with shank sizes of 3/8 inch or slightly smaller.
BrandFulton #ad
ManufacturerFulton Woodworking Tools and Accessories #ad
Part Number927

2. IVY Classic

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High Carbon Steel, 1/Tube, IVY Classic 46152 4-Inch Forstner Bit Extension

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IVY Classic #ad - Shank: 3/8-inch, length: 4-inch. To fasten the shank in place, use the hex key to tighten these screws. Ideal for use with any 3/8" shank bit. Two set screws and hex key included. Extends any forstner shank bit an additional 4 inches, Swift Bore Registered Trademark. High-carbon steel construction, precision ground and polished.
BrandIVY Classic #ad
ManufacturerIVY Classic Industries #ad
Height0.63 Inches
Length4 Inches
Weight0.03 Pounds
Width0.63 Inches
Part Number46152
Model46152

3. Fulton

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Fulton 10 inch Long Forstner Bit Extension for Adding Over 8" of Drilling Depth to Your Forstner Bit Ideal for Wood Turners Furniture Carpentry and Construction 3/8 inch Collet

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Fulton #ad - The forstner bit extension gives you additional 8-1/2 inches of reach to bore deeper into your projects. The collet inside diameter is 3/8 inch. The forstner bit extender is made from solid, heavy duty machined steel. Drilling with forstner bits to achieve a flat bottom hole or to start a deep hole turning project like on a larger vase or vessel is essentially impossible with a standard length forstner bit.

The minimum size hole this extension will allow you to drill is 13/16 inch. This tolerance is very tight and designed to accept forstner bits with shank sizes of 3/8 inch or slightly smaller. Forstner bits and Machinery shown in pictures are NOT included. However, the extension works exceptionally well for projects like salt shakers, pepper mills or even wood turned beverage mugs.

The extension can be used with forstner bits on drill presses, lathes with a drill chuck installed drill chuck not included or with a power drill. This will help you create larger diameter starter holes or help when you need to drill in just a little further than the standard bit length will allow. It is designed to be used with forstner bits only. This means the set screws may protrude outwardly from the collet. If you measure your bit shank and it is 3/8 inch, your bit should fit once the set screws are loosened.
BrandFulton #ad
ManufacturerPeachtree Woodworking Supply Inc. #ad
Part Number200-2206
Model2206

4. Century Drill & Tool

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Century Drill & Tool 38112 12" Ship Auger Extension, 3/8" Shank

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Century Drill & Tool #ad - 12" length. Extension’s shank fits ½" drill chucks. For use with ship auger bits with 3/8” hex shanks. Securely grips ship auger drill bits for extended length.
BrandCentury Drill & Tool #ad
ManufacturerCentury Drill & Tool Corp #ad
Height0.75 Inches
Length12 Inches
Weight0.35 Pounds
Width0.75 Inches
Part Number38112
Model38112

5. Taytools

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Taytools 774403 6-3/4 inch Round Shank Forstner Drill Bit Extension for 3/8 Inch Round or Hex Shafts

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Taytools #ad - Hole opening is. 375 inches and hole depth 1-3/8 inches. This round shank forstner bit extension will extend the reach of any Forstner bit 3/4 inch and larger with a 3/8” hex or round shank. Note: will fit auger bits. Overall length 6-3/4 inches and adds up to 5-5/8 inches of drilling depth. Contains two set screws for a secure grip on bits. Made from precision machined steel. Hex wrench included. Can be used in a hand drill, drill press or lathe.
BrandTaytools #ad
ManufacturerTaylor Toolworks #ad
Part Number774403

6. Peachtree Woodworking Supply

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Furniture, 10” Long Forstner Bit Extension for Adding Over 8" of Drilling Depth to Your Forstner Bit. for Wood Turners, Carpentry and Construction Use 10" x 3/8" Extension for 3/8" Forstner Bits

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Peachtree Woodworking Supply #ad - Can be used with hand drill as well. This is often not enough of a depth for many of your projects and it can get quite frustrating without the proper tools. The 10” forstner bit extensions are available in two different shank diameters: 3/8” and ½”. 10” long by 3/8” extension has an inner diameter of 3/8” and an outer diameter of ¾” and works with bits 25/32” in diameter or larger.

Worse yet, even with a standard length extension you’ll probably only add about 3” of depth to your bit. The bits are secured with two hex socket set screws using a hex key wrench which is included. This means that the 3/8” extension will accept 3/8” shank forstner bits while the ½” extension will accept ½” shank forstner bits. With the 10” long forstner bit extension you can now add over 8” of extra drilling depth to your current forstner bits! That alone makes this extension especially ideal for woodturners when having to hollow out large vessels or objects like salt and pepper shakers.

The extension also works great for rustic furniture, joining wide timbers, wooden beverage mugs and even works great on things like turned kaleidoscopes. Unlike other brands of forstner bit extensions, this extension is non proprietary so they will work with most any brand of forstner bit. To be certain, please make sure your bits fall into the correct socket size before purchasing. The 10” forstner bit extensions are made from heavy duty solid machined steel and feature a 3/16” thick socket wall to firmly hold the bits in place.
BrandPeachtree Woodworking Supply #ad
ManufacturerPeachtree Woodworking Supply inc. #ad

7. Alfa Tools

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Alfa Tools FB61492 3/8 x 5 1/8" Forstner Bit Extension

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Alfa Tools #ad - 5-1/8-inch overall Length, 3/8-inch Shank. Premium quality design. Forstner Bit Extension Shank. Quantity - 1 per Pack. 3/8-inch barrel Inside Diameter.
BrandAlfa Tools #ad
ManufacturerAlfa Tools #ad
Height0.63 Inches
Length5.13 Inches
Weight0.06 Pounds
Width0.63 Inches
Part NumberFB61492
ModelFB61492

8. WOODRIVER

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Forstner Bit Extension 3/8" x 10"

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WOODRIVER #ad - Woodriver is proudly made by woodcraft, wood stain and paint, power tools, routers, america’s leading supplier of saws, videos, planes, hand tools, dust collection and more.

Designed for use with WoodRiver forstner bits only. Extension adds 10” to length of forstner bit. Socket accepts forstner bits with 3/8” diameter shanks. Our award winning family of brands includes WoodRiver, sanding, Highpoint, Woodcraft and Woodcraft Magazine as well as the greatest selection of woodworking books, kits, wood, and plans. Forstner bit held in extension socket with two set screws - 3/8” diameter drive shank allows use of multiple extensions.
BrandWOODRIVER #ad
ManufacturerWoodcraft Supply #ad
Height0.85 Inches
Length11 Inches
Weight0.45 Pounds
Width1.9 Inches
Part Number147999W

9. WOODRIVER

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Forstner Bit Extension, 3/8" x 4"

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WOODRIVER #ad - Designed for use with WoodRiver forstner bits only. Our award winning family of brands includes woodriver, wood, america’s leading supplier of saws, sanding, Highpoint, kits, planes, Woodcraft and Woodcraft Magazine as well as the greatest selection of woodworking books, wood stain and paint, hand tools, videos, and plans.

Socket accepts forstner bits with 3/8” diameter shanks. Extension adds 4” to length of forstner bit. Forstner bit held in extension socket with two set screws - 3/8” diameter drive shank allows use of multiple extensions. Woodriver is proudly made by woodcraft, routers, power tools, dust collection and more.
BrandWOODRIVER #ad
ManufacturerWoodcraft Supply #ad
Height0.8 Inches
Length5.15 Inches
Weight0.26 Pounds
Width2.35 Inches
Part Number145705W

10. Alfa Tools

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Alfa Tools FB61490 5/16 x 5" Forstner Bit Extension

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Alfa Tools #ad - 5/16-inch barrel Inside Diameter. Quantity - 1 per Pack. Forstner Bit Extension Shank. 5-inch overall Length, 3/8-inch Shank. Premium quality design.
BrandAlfa Tools #ad
ManufacturerAlfa Tools #ad
Height0.63 Inches
Length5 Inches
Width0.63 Inches
Part NumberFB61490
ModelFB61490