If a standard tap can’t reach the thread start in a deep, recessed, or through-bored feature, you need a special extra long tap: a custom tap built with extended overall length or neck length to clear shoulders, bosses, and fixtures. As a Canadian tap manufacturer, Taylor Tool builds these long reach taps to your drawing or sample, matched to your thread form, material, and tolerance. This guide covers when to specify one, what to define up front, and how to avoid breakage in deep hole tapping.
What Are Special Extra Long Taps?
Special extra long taps are taps with extended overall length or extended neck length, designed to thread deep, recessed, or through-bored features that a standard-length tap cannot reach. Standard-length taps stocked by general suppliers work for ordinary hole depths; once geometry gets in the way, an extended length tap is the practical answer.
Taylor Tool manufactures special thread taps to your exact thread form, material, and tolerance rather than offering off-the-shelf compromises. Whether you need a modified standard or a completely unique tool, our engineering team works from your drawing or sample. If you’re not sure whether a stocked tap will clear your part, treat that uncertainty as your cue to go custom.
When Do You Need an Extra Long Tap?
You need an extra long tap when standard reach cannot clear a shoulder, boss, fixture, or deep bore to get to where the thread begins. If the tap’s flutes can’t reach the hole start without the shank or holder colliding with the part, standard length is out.
Typical cases include:
- Recessed holes where the thread starts below a counterbore or shoulder
- Thick sections where thread length plus approach exceeds a standard tap’s reach
- Tapping through housings where the tool must pass through one feature to thread another
- Long-reach tooling setups where fixtures or adjacent geometry limit access
These situations come up across the industries Taylor Tool supplies: automotive, aerospace, and power generation, as well as general manufacturing. For a broader look at one-off requirements, see our special purpose taps page.
Key Specifications to Define Before You Order
Before ordering, define the thread form, overall length, thread length, shank and neck dimensions, and tool material. Getting these on the drawing up front avoids back-and-forth and lets us quote accurately.
| Specification | Why it matters | What to send |
|---|---|---|
| Thread form | Determines geometry and tooling | Standard, size, and pitch, or the special form required |
| Overall length | Sets the reach to the thread start | Required length measured from your part geometry |
| Thread length | Controls how deep the cutting portion runs | Full thread depth plus any required approach |
| Shank diameter | Must fit your holder or spindle | Shank size and any drive style |
| Neck relief | Clears the bore or shoulder behind the thread | Bore or opening diameter the neck must pass through |
| Flute style | Governs chip evacuation | Through hole or blind hole, and workpiece material |
| Hand of thread | Right-hand or left-hand | Specify clearly, including left-hand requirements |
| Tolerance | Defines thread class and fit | The class or tolerance your part drawing calls out |
| Material/substrate | Affects wear and tool life | Workpiece material and production volume |
Don’t have a finished drawing? Taylor Tool can work from your drawing or sample, so send what you have.
Choosing Flute Style and Chip Control for Deep Holes
Chip evacuation is the main risk in deep taps, so flute style is the most important choice after length. The longer the cut, the more chips must travel out of the hole, and packed chips are a leading cause of broken taps and poor threads.
- Spiral point taps push chips forward, which makes them ideal for through holes. See our spiral point taps.
- Spiral flute taps pull chips up and out, making them ideal for blind holes and stainless steel. The question “what flute style is best for deep blind holes?” usually lands here. Explore high performance spiral taps.
- Form (thread-forming) taps produce no chips at all in ductile materials and yield stronger threads, which removes chip evacuation from the equation entirely.
Match the flute style to hole type and material, and tell us both when you request a quote.
Substrate and Material Options: HSS, Carbide, Powdered Metal
Match the tap substrate to your workpiece hardness, abrasiveness, and production volume. A long-reach tap that wears quickly costs you in downtime and cost per hole.
| Substrate | Best suited for |
|---|---|
| HSS taps | General-purpose tapping across a wide range of materials |
| Carbide taps | Hardened steels, high-silicon aluminum, and other abrasive materials where tool life and consistency drive cost per hole |
| Powdered metal taps | Heavy machining, thanks to an exceptionally uniform, tough substrate |
For a long-reach tap in demanding production, the real question is “carbide or HSS?” If you’re threading abrasive or hardened material at volume, carbide taps are worth discussing. For tough, heavy cuts, powdered metal taps offer a uniform substrate. Ask Taylor Tool’s engineers which suits your application.
Extra Long Taps for Special Thread Forms
Extended-length taps can be built in specialty thread forms well beyond metric and unified. If your part calls for an unusual form and a long reach, both can be combined in one custom tool.
Taylor Tool manufactures taps for Acme, trapezoidal, buttress, Whitworth, BSPT, BSPP, and PG threads, and more. We also build left-hand, multi-lead, and large-diameter taps, so yes, extra long taps can be left-hand threaded. For related custom work, see our special Acme taps and special form taps pages.
Tips to Avoid Breakage and Poor Threads in Deep Tapping
Rigidity, alignment, lubrication, and chip clearing drive success in deep hole tapping. Long taps are more flexible than short ones, so small errors multiply with reach.
- Support the tool. Use a guide or support so the long tap doesn’t deflect on entry.
- Keep alignment true. Any misalignment between spindle and hole is magnified along the length of the tap.
- Lubricate consistently. Make sure coolant or lubricant reaches the cutting zone, not just the hole opening.
- Clear chips. Back the tap out periodically on deep holes to break and clear chips before they pack the flutes.
- Confirm parameters. Speeds and feeds depend on material, tap geometry, and setup, so confirm them with Taylor Tool engineering rather than guessing. Our engineering data resources are a good starting point.
Ordering Custom Extra Long Taps from Taylor Tool
To order, send your drawing or sample and Taylor Tool will quote and build to your specification. We’ve been a Canadian manufacturer of special taps, reamers, and dies since 1918, and our 24 HR Jet Tap service is available for production-critical needs.
In Canada, Taylor Tool sells through a distribution network; our sales team can direct you to your nearest distributor. For U.S. ordering, contact sales directly, as we’re expanding our U.S. network.
Call Canada: 1-800-265-2145 | USA: 1-855-221-8277 Email: sales@taylortool.com Taylor Tool, 4 Goebel Avenue, Cambridge, ON N3C 1Z1
Contact us or use Request a Quote to get started.
Frequently Asked Questions
What is an extra long tap used for? An extra long tap threads deep, recessed, or through-bored holes that a standard-length tap can’t reach. The extended overall or neck length lets the cutting portion clear shoulders, bosses, and fixtures to reach the thread start.
Can you get taps made longer than standard length? Yes. Taylor Tool designs and manufactures custom taps to your specification, including special lengths. Send your drawing or sample, and our engineering team will work with you on the right solution.
How do you tap a deep hole without breaking the tap? Support the tool, keep alignment true, lubricate the cutting zone, and clear chips regularly. Choose a flute style suited to the hole, and confirm cutting parameters with Taylor Tool engineering.
What flute style is best for deep blind holes? Spiral flute taps are ideal for blind holes because they pull chips up and out of the hole. They also suit stainless steel. For through holes, spiral point taps push chips forward instead.
Do extra long taps come in special thread forms like Acme or BSPT? Yes. Taylor Tool builds specialty taps in Acme, trapezoidal, buttress, Whitworth, BSPT, BSPP, PG, and more. Contact sales with your thread form and length requirement.
Should I use carbide or HSS for a long-reach tap? It depends on your material and volume. Carbide suits hardened steels and abrasive materials like high-silicon aluminum; HSS covers general-purpose work. Ask Taylor Tool which fits your application.
What information do I need to send to order a custom long tap? Send thread form, overall length, thread length, shank and neck dimensions, flute style, hand of thread, tolerance, and workpiece material. A drawing or sample works.
Can extra long taps be left-hand threaded? Yes. Taylor Tool manufactures left-hand taps along with multi-lead and large-diameter options. Specify the hand of thread clearly on your drawing.
Does Taylor Tool make custom taps from a drawing or sample? Yes. Our engineering team works from your drawing or sample to deliver a tap built to your thread form, material, and tolerance.
How do I order special taps in Canada or the U.S.? In Canada, Taylor Tool sells through a distributor network, and our sales team will direct you to the nearest one. For U.S. ordering and lead times, contact sales directly at 1-855-221-8277.