When we set out to determine how to test how well impact drivers perform in restricted spaces, we found there needed to be more resources from manufacturers and online reviews. This outcome didn’t make sense, mainly since size and agility are essential factors determining how well impact drivers perform compared to each other.
We decided to dream up a more rigorous and standardized way of testing the spaces an impact driver can fit into with our clearance tests.
Below, we detail how we test impact driver clearances and why it matters. Check out our impact driver clearance test results to learn how each model in our test fleet fared in these tests.
What we test
We test the interior spaces each impact driver can fit into to drive screws. Each impact driver in our test fleet is tested in three scenarios to replicate practical driving situations in tight areas with limited access.
How we test it
We run three different interior clearance tests that are discussed in more detail below. Regardless of each iteration, we run the test with a 2-inch Dewalt torx impact driver bit and 1 5/8-inch torx screw, representing common driving scenarios around the home.
All models are tested with a 2Ah battery or the next highest Ah-capacity battery available on the battery platform. For example, Makita’s 40V XGT lineup was tested with a 2.5Ah battery since no 2Ah version is available.
We designed a test setup made of a box constructed with 2×4 lumber. A craft measuring mat is then attached to the bottom of the box for recording results in inches.
We round results to the nearest 1/8-inch measurement.
Minimum interior width clearance test
When held perpendicular to the driving material, we test the minimum width an impact driver can fit into with a bit inserted and a screw attached.
This test most closely replicates the minimum tip-to-back length an impact driver fits into, such as when driving between two vertical boards flanking both sides of your impact driver, and inside boxes.
Highly compact and sub-compact impact drivers with stubby-like collet-to-back lengths outperform in these tests.
Minimum top edge clearance test
When held perpendicular to the driving material, we test how closely to the obstructed top edge an impact driver can fit into with a bit inserted and screw attached.
This test most closely replicates how near the top edge an impact driver can drive screws perpendicularly, such as when driving screws under a shelf.
Minimum interior 45-degree clearance test
When held at a 45-degree angle to the left side of our testing apparatus, we measure the minimum distance from the top edge down to where the screw is inserted into the work materials with a bit inserted and the screw attached.
This test most closely replicates the minimum unobstructed vertical height for driving a screw or fastener through two separate materials, such as when driving a screw as close to the top edge as possible when holding an impact driver at an angle.
Highly compact and sub-compact impact drivers with stubby-like collet-to-back lengths outperform in these tests.
Why it matters
Measuring an impact driver’s Interior clearances determines how easily you can reach tight spaces to drive a screw or fastener. Undoubtedly, all homeowners and professionals on the job site will encounter situations where fasteners are driven in obstructed and tight spaces.
The better an impact driver performs in our clearance tests, the more versatile it is to drive fasteners in any situation
