MakerKiln

Drill Guide Block Generator

A 3D printable block that keeps a hand drill square to the work, for the bit sizes you set.

Holes

Thickness (bore length)

The block

Printed holes come out small. 0.2 mm lets the drill turn without wobble.

drag to turn · scroll to zoom
Length
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Width
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Thick
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Across
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Spacing
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Hole through the plateflat to flat
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Print time-rough, see below
PLA, estimated-
Printsflat, no supportsfence up
Price this print in the cost calculator →

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Local onlyThe jig is built and checked by JavaScript in this tab, and the STL is made on your computer. Your settings are remembered in this browser's local storage, and nothing is uploaded.

Drilling a straight hole by hand is hard. The bit wanders as it starts and leans as you push, and by the time you notice, the hole is off. A guide block fixes that: a thick block of plastic with the hole bored dead square, that you hold on the work and drill through. The longer the bore, the straighter the bit has to run.

What each setting does

Bit diameter. The size of drill you are guiding. The number you set is the finished hole; the tool adds a little clearance so a printed hole still passes the drill cleanly.

Bores and spacing. One bore does one size. Set several in a row and you get a block for a whole set of bits, each labeled by where it sits. Keep the spacing wide enough that the walls between bores stay solid.

Thickness. This is how long the bore is, and it is what keeps the bit square. Aim for at least one and a half times the bit, more for a small bit in thick stock. A block too thin lets the drill lean.

Printing it

The block prints flat with the bores running top to bottom, so no supports are needed. Use 100% infill and 0.2 mm layers, and PETG if you can, because it wears better than PLA. For a block you will use for years, choose the bushing option and press a steel bushing into each bore, since a drill turning in bare plastic slowly wears the hole oversize.

Before you download

The file is read back before the button turns on: every edge has to be shared by exactly two triangles, every face has to point outward, and the solid has to have a positive volume. When a setting cannot make a sound block, such as bores that overlap, the page says why instead of handing you a broken file.

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