Why only six
Most work is done with very few bits: two cross-head sizes, two of whichever star or square drive your screws use, a slotted bit and one spare. A strip for exactly those lives where the work happens: on the drill shelf, inside the lid of a driver case, stuck to the side of a cabinet with a strip of double-sided tape. It is short enough to go in a shirt pocket, and because it is one row every bit can be gripped from both sides. When a bit wears out you see the empty pocket at once, which does not happen in a box of thirty.
What to measure
Measure one of your bits across two opposite flats of the hexagon. Standard bits are 6.35 mm, usually reading 6.30 to 6.35. Do not measure corner to corner, which gives about 7.3 mm and pockets that are far too loose. Then measure the place the strip will go. The strip is 60.6 mm long and 13.6 mm deep; every pocket you add or remove changes the length by 9.6 mm, so five bits make a 51 mm strip and seven a 70.2 mm one.
Clearance, walls and pocket depth
A clearance of 0.25 mm makes each pocket 6.6 mm across flats, a sliding fit in PLA: the bit drops in and lifts out with two fingers. For a strip that rides in a pocket or a tool bag, use 0.15 mm so the bits need a light push and do not shake out. The walls between pockets and around the edge are 3 mm. The strip is 14 mm high over a 2 mm floor, so the pockets are 12 mm deep, about half of a 25 mm insert bit. That is deeper than on the longer strips of this site, because a short strip gets carried around and tipped over more.
Printing
Print the strip flat on the bed with the pocket openings upwards, as generated. No supports are needed. Use 0.2 mm layers and three perimeters; with walls of 3 mm almost the whole strip is perimeter and the infill setting hardly matters. The pocket floors are printed over the solid base, so they come out closed and flat. The strip takes about half an hour on most printers and uses a few grams of filament, so try one clearance, test it with your own bits, and reprint with a different value if the fit is not what you want.
Outline drawing
To scale. Pocket centres are 9.6 mm apart; the first and last pockets are 3 mm from the ends.
Parameters the generator will use
| Setting | Link parameter | Value |
|---|---|---|
| Model | model | bit_holder |
| Bits per row | count | 6 |
| Rows | rows | 1 |
| Bit size across flats | across_flats | 6.35 |
| Pocket clearance | clearance | 0.25 |
| Wall between pockets | gap | 3 |
| Wall around the pockets | margin | 3 |
| Strip height | height | 14 |
| Floor under the pockets | floor | 2 |
All lengths are in millimetres. Outer size from these values: about 60.6 x 13.62 x 14 mm.
Open the generator with these values
This model needs the $7 licence key: one payment, one key, and it opens all five paid models. Get a licence key on Gumroad ($7)
The hex bit holder strip needs a licence key: without one the generator shows the model locked, lists the values from this link and fills them in as soon as you unlock. The fitted drawer organiser bin is the free model and downloads with no key.