0.2 is the example result. Read it using the units and relationship stated below.
Tap Drill Size uses tap major diameter (in), thread pitch (in).
Keeping feed calculations attached to the cutting conditions
For tap drill size, the relationship is Result = [Tap major diameter (in)] − [Thread pitch (in)]. The amount depends on the supplied tap major diameter (in), thread pitch (in), rather than a live market price or a value imported from another record. A machining relationship connects diameter, speed, feed and engagement. It does not choose a safe starting point without the cutter, material and setup. Manufacturer cutting data should provide the process assumptions used in the form.
What the model includes
Result = [Tap major diameter (in)] − [Thread pitch (in)] Keep millimetres and metres distinct, and record whether feed is per tooth, per revolution or per minute. A correct conversion can still be unsuitable when tool reach, workholding, machine limits or chip evacuation changes. Use the result as a conversion or comparison, then validate the process against the tool guidance and machine capability. This page does not replace a tested setup sheet or account for every cutting condition.
Example with the supplied inputs
Tap major diameter (in): 0.25; Thread pitch (in): 0.05. Result: 0.2. The values are illustrative.
Compare one changed input
Tap major diameter (in) changes from 0.25 to 0.275. The result becomes 0.225. All other inputs remain fixed.
Calculation rule
Result = [Tap major diameter (in)] − [Thread pitch (in)]
Inputs and output
| Input | Example value | Entry convention |
|---|---|---|
| Tap major diameter (in) | 0.25 | Measure tap major diameter (in) in the displayed unit. Convert the source measurement before entry if it uses another system; a changed label does not perform a unit conversion. |
| Thread pitch (in) | 0.05 | Use the source quantity represented by thread pitch (in). Keep the counted population fixed and avoid mixing a unit value with a period total. |
Output: 0.2 is the example result. Read it using the units and relationship stated below. Use the formula to distinguish a cash amount, count, percentage or ratio.
How to use the page
Collect the inputs
Gather Tap major diameter (in), Thread pitch (in). Use one period and the units shown in the form.
Run the calculation
Enter the values and select the action. The calculation rule above explains how the inputs produce the result.
Compare a scenario
Change Tap major diameter (in) on its own, keeping the other inputs fixed. Read both results before changing another assumption.
Worked example
With the example inputs listed above, the result is 0.2.
Change Tap major diameter (in) from 0.25 to 0.275 while keeping every other value fixed. The result becomes 0.225. This comparison isolates that input; it does not forecast how other variables will respond.
Check the stated formula, units and limits before using the result in a decision.
Keep the displayed formula, input units and model scope with the result. Corrections or questions can be sent through the request section on this page.
Content updated: October 11, 2026