Short, Rigid Drilling for Tough Metalwork
Sutton Tools Stub Cobalt Coated Drills are made for machinists, fitters, metal fabricators, automotive workshops & maintenance teams that need a compact drill for controlled holemaking in metal. Their shorter format makes them particularly useful for shallow holes where reduced drill flex, limited machine clearance & a rigid setup matter more than the extra reach of a standard jobber drill.
For a tradesperson choosing a stub drill, diameter is only the beginning. Workpiece material, required hole depth, available clearance, drilling equipment & what happens to the hole afterwards should all influence the selection.
A short cobalt drill makes the most sense when its compact construction solves a real problem—whether that's keeping the setup rigid on a machine, working around a restricted component or repeatedly drilling shallow holes in demanding workshop conditions.
Explore Drills, Drill Accessories or Cutting Tools for related holemaking equipment.
What Are Sutton Tools Stub Cobalt Coated Drills?
Stub drills are shorter than conventional jobber-length drills.
That reduced overall length means less unsupported drill between the chuck or holder & cutting point. Where extra flute length isn't required, the compact format can provide a more rigid drilling arrangement.
Cobalt refers to the cutting-tool material used in the drill, while the coating forms part of the working surface. Together with the drill geometry, these features make this style particularly relevant to professional metalworking.
Stub cobalt coated drills can suit jobs where the operator needs:
► A short drilling setup
► Reduced drill flex
► Controlled shallow-hole drilling
► Better access in restricted setups
► Metalworking capability
► Repeatable workshop holemaking
They're not simply shortened jobber drills for every application.
The useful advantage appears when the hole itself doesn't require a longer drill.
Why Choose Sutton Tools Stub Cobalt Coated Drills?
Imagine a steel bracket that only needs a relatively shallow hole.
A long drill provides reach the job doesn't need. That additional length also places the cutting point further from the chuck or holder.
A stub drill takes the opposite approach.
Its compact construction keeps the cutting point closer to the tooling interface, which can be useful where rigidity & clearance are priorities.
That makes Sutton Stub Cobalt Coated Drills particularly relevant to machinists, fabricators & repair workshops working with metal components that don't require deep-hole capability.
The cobalt construction also gives buyers a drill option aimed beyond ordinary light-duty holemaking.
Common Applications
Machine-Shop Holemaking
Stub drills can be a practical choice on suitable mills, pedestal drills & other controlled workshop machinery where shallow holes are required.
The compact format becomes especially useful when a component, fixture or machine arrangement leaves limited room between the spindle & workpiece.
Steel Fabrication
Brackets, plates, mounts & fabricated components frequently require holes that are relatively shallow compared with their diameter.
A stub drill can keep the drilling setup compact without carrying unnecessary flute length into the job.
For surrounding metalworking equipment, browse Metal Cutting & Grinding Tools.
Automotive Workshop Work
Repair brackets, mounts, fabricated modifications & workshop-made components can all require drilling in steel or other suitable metals.
Restricted access around an existing component can also make overall drill length relevant before cutting begins.
For a look inside day-to-day workshop work, read A Day With An Automotive Mechanic Peninsula.
Repetitive Shallow Holes
When multiple components need the same shallow hole, consistency becomes more important than unused reach.
A correctly selected stub drill can keep the tooling arrangement compact while the operator concentrates on positioning, cutting conditions & repeatability.
Maintenance & Repair
Maintenance work rarely arrives in perfectly convenient shapes.
Housings, fixtures, guards & existing assemblies can restrict the available drilling space. A shorter drill can help where access is limited & the required hole depth remains within the tool's working capacity.
Product Selection Guide
Choose the Diameter Around the Finished Job
Start with the required hole size, then consider what happens next.
Is the hole accepting a bolt? Will it be tapped? Does it need subsequent reaming? Is it simply a clearance hole?
Those questions matter because drilling is often preparation for another operation.
For threaded-hole work after drilling, browse Tap & Die Sets.
Check Hole Depth Before Choosing Stub Length
A stub drill is deliberately compact.
That advantage disappears if the required hole exceeds the practical flute capacity of the tool.
Check the component drawing or measure the required depth before choosing between stub, jobber or longer drill formats.
Identify the Workpiece Material
“Metal” isn't specific enough.
The demands of drilling mild steel can differ from stainless steel, harder steels, cast materials or non-ferrous metals.
Check the individual Sutton drill's material suitability & use cutting conditions appropriate to the actual workpiece.
Look at Available Clearance
Measure the space available around the job.
Large components, fixtures & restricted machine travel can make overall drill length an important selection factor.
A shorter drill may provide the required working room without introducing unnecessary reach.
Consider the Following Operation
A hole intended for tapping deserves different preparation from a general clearance hole.
Likewise, a drilled feature that will later be reamed or used for accurate component location may require closer attention to the initial drilling setup.
Knowing the complete sequence helps avoid selecting the drill in isolation.
Expert Tips
Keep the Workpiece Secure
Short tooling won't rescue an unstable component.
Support & clamp the workpiece appropriately before drilling, particularly when dealing with irregular repair parts, fabricated brackets or smaller components.
For workshop workholding, explore Clamps & Vises.
Check the Chuck or Holder
If the drill appears to run off-centre, don't immediately blame the cutting edges.
Inspect the chuck or holder, mating surfaces & spindle condition.
A compact drill setup works best when the tooling holding it is also in sound condition.
Match Speed to the Job
Cobalt construction doesn't mean the drill should simply be run faster.
Diameter, workpiece material, cutting conditions & drilling equipment all affect the appropriate approach.
Too much speed can create unnecessary heat, particularly when drilling demanding metals.
Don't Substitute Pressure for Correct Cutting Conditions
Pushing harder isn't always the answer when a drill stops cutting efficiently.
If progress changes, check the cutting edges, speed, chip evacuation & workpiece conditions before applying more force.
Pay Attention to the Chips
Swarf gives the operator useful feedback.
A noticeable change in chip formation, cutting sound or heat can indicate that the process is changing.
Investigate unexpected behaviour before continuing through a batch of components.
Stub Drill vs Jobber Drill
The key difference for the buyer is usable length.
A jobber drill provides additional flute length & reach for general drilling.
A stub drill sacrifices unnecessary length to create a shorter tooling arrangement.
Choose a stub drill when:
► The hole is relatively shallow
► A compact setup is desirable
► Machine clearance is restricted
► Reduced drill flex is valuable
► Additional reach provides no practical benefit
Choose a longer drill when the required depth or component geometry genuinely demands it.
The best drill isn't automatically the longest tool that reaches the workpiece. It's the shortest suitable format that can complete the required hole safely & effectively.
When the Hole Will Be Tapped?
Drilling becomes particularly important when an internal thread follows.
The preparation hole gives the tap the material condition it has to work with.
Check the required tapping drill diameter rather than selecting a drill that merely looks close.
Depth matters as well.
A blind threaded hole may require additional drilled depth beyond the usable thread length to accommodate the tap geometry & provide appropriate clearance.
Measure the preparation work before committing the component to threading.
Cobalt Drills & Demanding Metals
Cobalt drills are widely associated with professional metalworking because their cutting-tool material is suited to more demanding drilling applications than ordinary general-purpose tooling.
That doesn't make every cobalt drill suitable for every metal.
The individual drill specification, coating, geometry, workpiece material & cutting conditions still determine whether the tool belongs in the job.
For a machinist or fitter, that distinction matters most when working with stainless steel, harder materials or repetitive drilling where heat & cutting-edge condition can become increasingly important.
Know When the Drill Needs Attention
A drill doesn't have to snap before it tells you something has changed.
Watch for:
► Increasing cutting effort
► Additional heat
► Poorer chip formation
► Changing hole quality
► Unusual noise
► Visible cutting-edge wear
If a familiar drilling operation begins behaving differently, inspect the drill & setup before moving directly to the next component.
For practical guidance around cutting-edge condition, read The Black Print: Blade Sharpening 101 Sharpen Or Replace.
Keep Stub Drills Protected Between Jobs
Short drills still have precision cutting edges.
Once safely removed from the machine, clean the drill appropriately, inspect the point & store it where the cutting edges won't repeatedly contact other metal tools.
Keeping individual sizes organised also reduces unnecessary handling when the next drilling job begins.
For organised workshop tooling, browse Tool Storage.
For broader workshop-care guidance, read How To Clean Your Gear Without Ruining It.
