Buy Chucking Reamers Online in Australia
Chucking Reamer Sizes — Quick Reference (H7 Tolerance)
Chucking reamers are precision toolroom cutters used in lathe, drill press or CNC to finish a pre-drilled hole to controlled tolerance and surface finish. AIMS stocks HSS chucking reamers from Sutton and Dormer in metric and imperial sizes. Manufactured to H7 tolerance class (the standard finish for bearing fits, dowel holes, pin locations).
| Reamer Ø | Recommended Drill Ø (Pre-Drill) | Common Use |
|---|---|---|
| 3.0 - 5.0 mm | 2.9 - 4.85 mm | Pin holes, instrument work |
| 6.0 - 10.0 mm | 5.85 - 9.85 mm | Small dowels, light bearing fits |
| 12.0 - 16.0 mm | 11.85 - 15.85 mm | General workshop reaming, medium dowel holes |
| 18.0 - 25.0 mm | 17.85 - 24.85 mm | Machinery dowel + alignment holes |
| 28.0 - 40.0 mm | 27.85 - 39.85 mm | Heavy machinery, large pin locations |
Pre-drill rule: leave approximately 0.05 mm × reamer Ø material for the reamer to remove. Too little material = wandering / poor finish; too much material = reamer dulls fast. Use cutting fluid for all reaming work. For deeper holes, see long drill bits. For adjustable hand reaming (multiple sizes from one body), see adjustable hand reamers. For complete background, see our reamer guide.
Chucking Reamers
AIMS Industrial stocks HSS chucking reamers for machine reaming on lathe, drill press and CNC machining centre — precision toolroom cutters designed to bring a pre-drilled or bored hole to a specific finished diameter with tight dimensional tolerance and a fine surface finish. Where a drill leaves a rough, slightly oversized hole with tool marks on the bore wall, a chucking reamer finishes the hole to a controlled tolerance class, producing a surface suitable for bearing fits, pin locations, dowel holes and seal bores. Sutton and Dormer are the primary brands — well-regarded in Australian toolrooms for consistency and long tool life on ferrous and non-ferrous materials.
Straight Flute vs Spiral Flute
Chucking reamers are available in two flute configurations. Straight flute reamers produce a fine, consistent finish on through-bores in medium to low rigidity setups such as manual lathe tailstock work and sensitive drill press applications — they are the standard choice for general toolroom reaming. Spiral flute reamers cut more aggressively and direct chips away from the cutting zone more efficiently, making them the preferred choice for deep bores, blind holes, interrupted cuts and CNC work at higher spindle speeds. The helix also produces a smoother bore finish on materials that tend to drag or tear under straight flute action.
Size Range and Shanks
The range covers metric diameters from 1 mm through to 50 mm in 0.5 mm increments, with imperial sizes from 1/16″ through to 2″ for inch-dimensioned components and legacy equipment. Shank configurations include straight shank for Jacobs or ER collet chuck mounting and Morse taper shank for direct tailstock mounting on lathes. The right shank for your machine eliminates adaptor stacks and maintains the rigidity essential to good reaming results.
HSS and HSS Cobalt Grades
Standard HSS chucking reamers handle the full range of engineering steels, cast iron, brass, bronze and aluminium at moderate speeds — typically 20 to 60 SFM depending on material and bore diameter. HSS cobalt reamers are specified for harder materials, stainless steels, heat-resistant alloys and production applications where higher cutting speeds are required to maintain throughput. Cobalt grade tools retain their cutting edge at elevated temperatures and resist the built-up edge that can occur when reaming work-hardening materials. For most toolroom and maintenance applications, standard HSS provides adequate tool life at lower tooling cost.
Tolerances and Applications
Chucking reamers are used wherever a drilled hole must be brought to a specific tolerance class — typically H7 for sliding fits and clearance locations, H6 for precision fits, or custom tolerance bands specified by the designer. Common applications include finishing bearing housing bores to accept bearing ODs without press interference, producing dowel pin holes in jigs and fixtures, reaming pivot and hinge pin bores in fabricated assemblies, and preparing hydraulic cylinder and valve port bores for sealing. Achieving surface roughness values in the Ra 0.4 to 1.6 µm range is routine with quality reamers and correct cutting parameters.
Setup and Technique
Reaming relies on rigidity throughout the setup — floating holders or poorly supported workpieces lead to bell-mouthing, chatter and oversize bores. The pilot hole should be left 0.1 to 0.5 mm undersize depending on reamer diameter; too small an allowance causes premature wear and poor finish, too large causes the reamer to cut on the outer corners and produce an oversize result. Cutting fluid appropriate to the workpiece material should be applied throughout — soluble oil for steel and cast iron, neat cutting oil for aluminium and brass. For assistance selecting the right chucking reamer grade, size or shank configuration for your application, contact our team. AIMS Industrial has been supplying precision tooling to Australian workshops since 1988.
People Also Ask — Chucking Reamers
Q: What's the difference between a chucking reamer and a hand reamer?
A chucking reamer is designed for machine use — held in a lathe chuck, drill press, or CNC spindle and driven by the machine at cutting speed. A hand reamer has a square drive tang for turning with a tap wrench and is designed for slow, manual finishing where the operator controls feed by feel. Chucking reamers cut faster and are the standard choice for production and machine-shop work; hand reamers suit fitting, repair, and situations where machine access isn't available.
Q: Can a chucking reamer correct a misaligned or crooked hole?
No — a chucking reamer follows the existing pilot hole and finishes it to size and finish, but it does not correct significant misalignment, taper, or off-centre drilling. If the pre-drilled hole is out of position or badly angled, the reamer will follow that error rather than fix it. Boring is the correct process for correcting hole position or removing significant stock; reaming is strictly a finishing operation on an already well-positioned hole.
Q: What speed should I run a chucking reamer at?
Chucking reamers run at roughly half the speed used for drilling the same material and diameter — typically 20-60 SFM (surface feet per minute) for HSS reamers depending on material hardness, with cobalt grades tolerating higher speeds. Running too fast generates heat and reduces tool life and finish quality; running too slow can cause chatter and a poor surface finish. Feed rate should be steady and continuous — stopping mid-cut leaves a step mark in the bore.
Q: Why is my reamed hole coming out oversize?
The most common causes are excessive stock left for the reamer to remove (the reamer pushes off-centre under load), a worn or chipped reamer, insufficient rigidity in the setup causing the reamer to wander, or reaming a hole that wasn't truly round to begin with. Confirm the pre-drill allowance matches the recommended amount for the reamer diameter, check the reamer for wear or damage, and ensure the workpiece and reamer holder are both rigidly supported.
Q: Do I need cutting fluid for every reaming operation?
Yes — cutting fluid is essential for good reaming results regardless of material. It reduces friction and heat at the cutting edges, flushes chips out of the flutes to prevent chip packing and surface scoring, and extends reamer life significantly. Use soluble oil or a water-based coolant for steel and cast iron, and a neat cutting oil for aluminium and brass to avoid built-up edge and achieve the best surface finish.
Q: What tolerance class can I expect from a quality chucking reamer?
A quality HSS or HSS-cobalt chucking reamer used correctly (right pre-drill allowance, correct speed, adequate cutting fluid, rigid setup) reliably holds H7 tolerance class — the standard for sliding fits, bearing bores, and dowel locations. Tighter tolerance classes (H6 or better) are achievable with premium reamers and careful technique, but consistency depends as much on machine rigidity and operator technique as on the reamer itself.