Explore essential tooling for milling machines including end mills, collets, vises, and coatings with expert 2025 buying tips and starter kits.

Core Types of Milling Cutters You Actually Need

When you’re setting up tooling for a milling machine, it’s easy to blow money on cutters you’ll barely touch. Let’s cut through the noise and focus on the core milling cutters you’ll actually use every week in a real shop.

End Mills for Milling Machines (Your Main Workhorses)

If you’re running a manual mill or CNC, end mills do most of the work. The key differences are flute count and geometry:

• 2-Flute End Mills
  • Great for: Aluminum, plastics, softer materials
  • More room for chips = better chip evacuation
  • Ideal for slotting and roughing in gummy materials
• 3-Flute End Mills
  • Great balance for: Aluminum and mild steel
  • Stronger than 2-flute, better chip evacuation than 4-flute
  • A very good “do-it-all” cutter for CNC users
• 4-Flute End Mills
  • Great for: Steel, stainless, and finishing passes
  • More cutting edges = higher feed potential and better surface finish
  • Not ideal for deep slotting in aluminum due to chip packing
• Variable Helix End Mills
  • Great for: CNC, tougher materials, chatter-prone setups
  • Uneven flute spacing breaks up vibration
  • Lets you take heavier cuts with a better finish and less noise

Bottom line:
For most shops, a smart starter set is:

• 2-flute for aluminum
• 3-flute as a general-purpose tool
• 4-flute and variable helix for steel and finishing

Square End, Ball Nose, and Corner Radius End Mills

You don’t need every shape under the sun, but you do need a few basic profiles:

• Square End Mills
  • Flat bottom, sharp corners
  • Use for: pockets, facing, slotting, general work
  • Default choice for most operations
• Ball Nose End Mills
  • Rounded tip
  • Use for: 3D contours, molds, fillets, organic shapes
  • Common on CNC when surfacing complex parts
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  • Common on Bridgeport-style knee mills
  • Flexible: you can run different shell mills on the same arbor
• Fly Cutters
  • Single-point cutter, often home-shop friendly and very cost-effective
  • Excellent for: mirror-like finishes on manual mills
  • Slower material removal, but great surface quality if your spindle is tight

General rule:

• Need speed and production? Face/shell mill.
• Need a beautiful finish on a manual mill, low budget? Fly cutter.

Roughing End Mills vs Finishing End Mills

You don’t mow a jungle with manicure scissors. Same idea here.

• Roughing End Mills (Corncob / Serrated)
  • Aggressive chip-breaking edges
  • Great for: heavy stock removal in steel and stainless
  • Lower cutting forces, less tool chatter
  • Leave a rough surface that needs a finishing pass
• Finishing End Mills
  • Smooth flutes and sharp edges
  • Great for: final passes to hit dimension and surface finish
  • Use after roughing for tight tolerances

Smart workflow:

• Use a rougher to hog material.
• Switch to a finisher to hit final size and finish.

Slot Drills and Woodruff Keyseat Cutters

Some features are just easier with the right dedicated tool.

• Slot Drills
  (In US terms, usually center-cutting end mills used specifically for slots)
  • Designed for plunging and full-width slot cutting
  • Good for accurate keyways, T-slot prep, and straight slots
• Woodruff Keyseat Cutters
  • Small, wheel-shaped cutters on a shank
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• Aluminum-Specific Cutters
  • Usually 2–3 flutes
  • High helix angle for fast chip evacuation
  • Polished flutes or ZrN coating are common
  • Designed to prevent chip welding and built-up edge
• Steel Cutters
  • Typically 3–4 flutes, tougher core
  • Coatings like AlTiN, TiSiN, or AlCrN for heat resistance
  • Optimized edge prep for durability rather than razor-sharp cutting alone
• Stainless Steel Cutters
  • Similar to steel tools but with even more focus on toughness
  • Coatings like AlTiN/AlCrN and specific geometries to handle work hardening
  • Shorter length and rigid setups are key

Practical advice:

• If you mostly cut aluminum: invest in a good set of aluminum-specific carbide end mills first.
• If you do a mix of aluminum and steel: get material-specific tools for your most common jobs instead of “one-size-fits-nothing” cutters.

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Key takeaway:
You don’t need a 200-piece assortment to get real work done. With a focused set of end mills, face/shell or fly cutters, a few specialty cutters, and material-specific geometries, your milling machine tooling will handle 90% of jobs cleanly, efficiently, and profitably.

Essential Tooling for Holding and Workholding on a Milling Machine

If you want accurate parts and consistent results, your milling machine tooling for holding and workholding matters just as much as the cutting tools. In a small U.S. shop or garage, smart choices here will save you broken cutters, bad finishes, and tons of setup time.

Spindle interfaces: R8, CAT, BT, ISO, MT

Your spindle taper dictates what tooling you can run, so start there:

• R8:
  • Common on Bridgeport-style knee mills and many benchtop mills.
  • Great balance of cost and accuracy.
  • Huge range of available tooling in the U.S. market.
• CAT40 / CAT50:
  • Standard in many American VMCs (CNC machining centers).
  • Very rigid, built for tool changers and heavy cuts.
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  • Used when the spindle itself is MT.
  • Good for basic setups, not my first choice for heavier cuts.
• 5C collets:
  • Excellent for holding round stock and small parts, especially in vises and fixtures.
  • More common for lathes and fixtures than for end mills.
• TG100 (and other TG):
  • High grip collets, often used where you really need extra holding power.
  • Good for aggressive milling, but more specialized.

For most benchtop and Bridgeport-style mills, I recommend an R8-to-ER32 or ER40 collet chuck as a primary workhorse, then add R8 collets for common shank sizes.

End mill holders, collet chucks, and Weldon shanks

How you hold the cutter affects finish, tool life, and chatter:

• Collet chucks:
  • Best balance of accuracy and flexibility.
  • Great for general machining, especially with small to medium cutters.
• End mill holders (set-screw/Weldon style):
  • Positive drive using the Weldon flat on the tool.
  • Less chance of the tool pulling out on heavy cuts.
  • Slightly more runout than a good collet chuck, but more secure.
• Weldon shank tools:
  • End mills with a flat ground on the shank.
  • Designed specifically for end mill holders.
  • I like these for roughing and heavy steel work.

My approach: use collets for most finishing and lighter cuts, and end mill holders for roughing or when tool pull-out is a risk.

Milling machine vises: 4-inch vs 6-inch, Kurt-style vs import

A solid vise is non-negotiable for accurate milling:

• 4-inch vise:
  • Great for small mills and benchtop machines.
  • Easier to move, less mass on a lighter table.
• 6-inch vise:
  • Standard on Bridgeport-size machines.
  • More clamping area, better for larger workpieces.
• Kurt-style vises:
  • Pull-down design minimizes jaw lift.
  • Consistent clamping and repeatability.
  • U.S.-made Kurt vises are pricier but worth it if you run the machine a lot.
• Import vises:
  • Budget-friendly for home shops.
  • Look for ground ways and low jaw lift. Many are good enough once cleaned and tuned.

If you’re in the U.S. starting out on a knee mill, a decent 6″ Kurt-style vise is often the single best investment in workholding you can make.

Clamping kits, step blocks, strap clamps, toe clamps

You won’t always put parts in a vise. A clamping kit is essential:

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• Parallels:
  • Used inside the vise to elevate the part and keep it parallel to the table.
  • Essential for through-holes and for keeping work flat and repeatable.

If you plan to machine materials like brass or bronze regularly, pairing good workholding with knowledge of the material’s behavior (for example, understanding its actual strength profile similar to the details in this guide on how strong brass really is: https://vast-cast.com/how-strong-is-brass-detailed-strength-and-durability-guide/) helps you choose clamping force and cutter strategy more confidently.

Edge finders, wigglers, and probing tools

Accurate setups are where you really feel the difference between “hobby” and “shop-quality” work:

• Mechanical edge finders:
  • Affordable and reliable on both manual and CNC mills.
  • Great for finding X/Y edges of your part.
• Wiggler sets:
  • Quick way to pick up center-punched marks and layout lines.
  • Useful on older manual machines and for rough setups.
• Probing tools (touch probes, 3D probe):
  • Best option for CNC machines.
  • Fast and accurate for part zero, bores, bosses, and complex setups.
• Test indicators:
  • Not technically a “workholding tool,” but critical for tram, vise alignment, and checking runout.

In a U.S. home or small pro shop, I’d start with:

• A mechanical edge finder
• A decent test indicator with a mag base
• One good Kurt-style vise
• A basic T-slot clamping kit

Then add fixture plates, toe clamps, and probing as your jobs get more complex and your milling machine tooling setup grows.

Tool Coatings and Geometry for Modern Milling Tooling

When you’re picking tooling for a milling machine, coatings and geometry matter just as much as the brand name. The right combo is what lets you push feeds, avoid chatter, and actually finish the job instead of burning up cutters.

Common Milling Tool Coatings (AlTiN, TiSiN, AlCrN, ZrN, TiN)

Here’s the short, real-world version of the main coatings you’ll see on end mills for milling machines:

• TiN (Titanium Nitride)
  • Entry-level gold coating
  • Good for mild steel and general-purpose work
  • Better than uncoated, but old tech compared to newer coatings
• AlTiN / TiAlN (Aluminum Titanium Nitride)
  • Go-to coating for steel and stainless in the U.S. job shop world
  • Handles high heat; loves higher surface speeds and dry or mist cutting
  • Great for harder materials and tool steels
• TiSiN (Titanium Silicon Nitride)
  • Very hard, very heat-resistant
  • Solid choice for high-speed machining and tougher alloys
  • Good for dry cutting in aggressive CNC applications
• AlCrN (Aluminum Chromium Nitride)
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Uncoated vs Coated End Mills on Small Milling Machines

For benchtop and smaller Bridgeport-style mills in U.S. home and small shops, you don’t always need high-end coatings:

• Uncoated carbide:
  • Great for aluminum and plastics
  • Ideal when your spindle speed is limited and you’re not generating huge heat
  • Often gives a cleaner finish on aluminum than some dark coatings
• Coated carbide:
  • Worth it for steel, stainless, and abrasive materials
  • More forgiving when your feeds and speeds aren’t perfect
  • Longer tool life, especially in production or repeated jobs

Rule of thumb:

• If you mostly cut aluminum: a good set of uncoated or ZrN-coated, polished-flute end mills is plenty.
• If you cut a lot of steel or stainless: step up to AlTiN or similar; the coating will pay for itself.

Variable Helix Geometry and Chatter Reduction

Variable helix end mills are a game-changer for chatter, especially on lighter mills and less rigid setups:

• What they do:
  • Change the helix angle from flute to flute
  • Spread cutting forces so vibration doesn’t build up at one frequency
• Why it matters:
  • Less chatter, better surface finish
  • You can push feed rate more without the mill “singing”
  • Very helpful on knee mills and benchtop CNCs with limited rigidity

If your machine chatters easily, a quality variable helix end mill is usually a better upgrade than just buying more horsepower.

Chipbreaker Flutes vs Polished Flutes

Chip control is a big deal in real-world cutting:

• Chipbreaker flutes:
  • Small “steps” or notches ground into the cutting edge
  • Break long chips into smaller pieces
  • Great for:
    • Roughing steel, stainless, and cast iron
    • Slotting and deep cuts where chips pack up
  • Downsides:
    • Rougher finish
    • Not ideal for final passes
• Polished flutes:
  • Smooth, shiny flute surfaces, often on aluminum-specific end mills
  • Help chips slide out and reduce sticking
  • Great for:
    • Aluminum, brass, plastics
    • High-speed, high-chip-load cuts with good coolant or air blast

A smart setup:

• Use chipbreaker roughers for hogging material.
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  • Great for:
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  • Pair of 1-2-3 blocks and a set of parallels
• Toolholding:
  • R8 or BT/ISO collet set matched to your spindle (depending on your machine)
  • One ER32 or ER40 collet chuck with a small starter set of collets
  • A few end mill holders for your most-used shank sizes (like 3/8″ and 1/2″)
• Cutting tools:
  • HSS or cobalt end mills in:
    • 1/8″, 3/16″, 1/4″, 3/8″, 1/2″ diameters
    • 2-flute for aluminum, 4-flute for steel
  • A couple of small center drills (No. 2 and No. 3)
  • Spot drill (for accurate hole locations)
• Setup and measurement:
  • Mechanical edge finder
  • Dial test indicator and magnetic base
  • 0–6″ digital caliper
  • 0–1″ micrometer (for more precise work)

This basic milling machine tooling setup lets you square stock, mill flats, cut simple pockets, and drill accurately without killing your budget.

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Budget-friendly starter tooling setup under a fixed cost

If you’re trying to stay under a fixed cost (say $500–$800 for tooling, which is common for new US hobbyists and side-hustle shops), prioritize as follows:

• Must-have (buy first):
  • Kurt-style 4″ vise (good import)
  • R8 (or your spindle type) collet set: 1/8″–3/4″
  • Mixed HSS end mill set (even an import set to learn on)
  • Edge finder
  • Clamping kit
• Nice-to-have (add as budget allows):
  • ER32 collet chuck with 1/8″–3/4″ collets
  • A quality 3/8″ and 1/2″ carbide end mill for aluminum
  • 1-2-3 blocks and parallels

General rule: spend more on the tooling that actually touches the part (end mills, vises, collets) and less on “assortment” kits you’ll rarely use.

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Intermediate tooling package for aluminum and mild steel

Once you’re past the basics and cutting aluminum and mild steel regularly, step up your tooling for better finish, faster cycle times, and longer tool life.

• Cutting tools:
  • Dedicated aluminum end mills:
    • 2- or 3-flute, high-helix, polished flutes
    • 1/8″, 1/4″, 3/8″, 1/2″ diameters
  • Carbon or low alloy steel end mills:
    • 4-flute AlTiN or AlCrN coated
    • Stub length for rigidity
  • A 2.0″–2.5″ face mill or shell mill for surfacing
  • One roughing end mill (corn cob) for heavy stock removal
• Workholding upgrades:
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  • Variable-helix carbide end mills to fight chatter
  • Longer-reach carbide only where absolutely needed

Use HSS for rough jobs and questionable setups. Use carbide when rigidity is good and the part matters. That’s how you get the best return on tooling for a milling machine.

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Professional-level tooling kit for daily shop use

If you’re running parts every day (job shop, small production, prototyping), your milling machine tooling package needs to be accurate, repeatable, and fast to swap.

Core shop-level tooling package:

• Toolholding:
  • Full ER32/ER40 collet chuck coverage
  • Dedicated end mill holders for heavy cutters
  • Balanced toolholders for high RPM CNCs
  • Shrink-fit or hydraulic chucks if you’re chasing tight tolerances
• Cutting tools:
  • Full carbide end mill library:
    • Multiple diameters, variable helix, stub and standard length
    • Material-specific lines for aluminum vs steel vs stainless
  • Roughing and finishing tools for each material
  • Indexable face mills (2–4″) for surfacing and squaring stock
  • Specialty cutters:
    • Chamfer mills
    • Slot drills
    • Radius and corner chamfer tools
    • Keyseat and T-slot cutters for standard features
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  • Two or more premium vises (Kurt, Glacern, etc.)
  • Vise soft jaws, parallels, and stops
  • Fixture plates with standard hole and dowel patterns
  • Modular fixturing clamps and low-profile toe clamps
• Process and QC:
  • Tool length measurement system (presetter or touch probe)
  • Structured tool libraries and tool life tracking

At this level, tooling equals throughput. The right tooling package can be the difference between a profitable job and a loss.

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Tooling packages for Bridgeport-style knee mills

Bridgeport-style knee mills are still everywhere in US shops. They’re versatile, and their tooling needs are a bit different from small CNC benchtop machines.

Core Bridgeport tooling package:

• Spindle and toolholding:
  • R8 collet set, 1/8″–3/4″
  • A few R8 end mill holders (3/8″, 1/2″, maybe 5/8″)
  • Drill chuck with R8 shank (0–1/2″)
• Cutting tools:
  • HSS and carbide end mills in common sizes
  • A 2″–3″ face mill or shell mill
  • Fly cutter for quick, clean faces
  • Keyseat cutters, Woodruff cutters, and T-slot cutters for classic Bridgeport work
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  • 6″ Kurt-style vise (this is the standard size on a Bridgeport)
  • Full clamping kit and angle plates
  • 1-2-3 blocks and parallels

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Common Milling Tooling Mistakes to Avoid

When you’re building up tooling for a milling machine, avoiding a few common mistakes will save you money, broken cutters, and ruined parts. Here’s what I see most often in small shops and home garages across the U.S.

1. Using the wrong flute count for the material

Flute count matters more than most people think.

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  • More room for chips to clear
  • Less chance of packing the flutes and snapping the tool
• Steel and stainless: 4–5 flute end mills work better
  • Stronger core, less deflection
  • Better tool life and nicer surface finishes

Rule of thumb:

• Soft, gummy, high-chip-volume materials → fewer flutes
• Harder, tougher materials → more flutes

2. Overusing long reach end mills

Long reach tools look “safe,” but they’re a bad default choice.

• Long tools chatter, deflect, and break easier
• They ruin surface finish and can oversize your pockets and slots

Use long reach only when you truly have to clear a wall. For 90% of your milling:

• Pick stub-length end mills
• Keep the tool sticking out of the holder as short as you can

3. Running carbide in bad holders or worn collets

Carbide is rigid and brittle. If your toolholding is sloppy, it will punish you.

Common issues:

• Worn collets: tool slippage, runout, random breakage
• Cheap or damaged holders: vibration and poor finishes
• Dirty tapers: chips between the spindle and toolholder kill accuracy

Invest in at least one solid ER collet chuck or quality R8 collet set and keep them clean. Even the best carbide end mills for aluminum or steel won’t perform if the holder is junk.

4. Ignoring spindle runout and cleanliness

Runout destroys tool life, especially on small diameters.

Watch for:

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If flood coolant isn’t realistic in your shop, a simple mist system or air blast is still a huge upgrade.

6. Using damaged or chipped end mills on critical work

Trying to “use up” bad tools on important jobs usually costs more in the end.

Signs you should pull the tool:

• Chipped corners
• Burned or discolored cutting edges
• Noticeable drop in surface finish or noise

Use rough or chipped tools only for:

• Roughing stock off non-critical parts
• Secondary operations where finish and accuracy don’t matter

For tight tolerances and good surface finish, always grab a sharp, known-good cutter.

7. Buying huge assortments instead of focused tooling

Those giant 50–100 piece “bargain” sets look tempting, but most of the tools never get used.

Instead:

• Build a focused core set of end mills you actually need
  • A few stub-length 2–3 flute mills for aluminum
  • A few 4–5 flute mills for steel
  • A couple of ball nose and corner radius tools
• Add specialty cutters (T-slot, dovetail, Woodruff) only when the job demands it

This way, your budget goes into quality tooling for milling machines you’ll use daily, not a drawer full of random sizes that just rust.

By fixing these common mistakes, your milling machine tooling runs smoother, lasts longer, and gives you cleaner, more accurate parts without wasting money on broken cutters and failed setups.

Maintenance and Storage for Milling Machine Tooling

Taking care of your milling machine tooling is non‑negotiable if you want consistent accuracy and long tool life. Here’s how I maintain and store end mills, shell mills, and holders in a small U.S. shop without wasting time or money.

Cleaning End Mills, Shell Mills, and Holders

Clean tools right after use—don’t let chips and coolant bake on.

• Wipe cutters and holders with a lint‑free rag.
• Blow chips out of flutes and tapers with low‑pressure air (not straight at your face).
• Use a soft brass or nylon brush on flutes; avoid scratching the cutting edges.
• For sticky coolant or oil, hit tools with a light solvent, then dry completely.
• Always clean the spindle taper and toolholder taper together—any debris here kills accuracy and increases runout.

Rust Prevention in a Small Shop

Humidity swings in U.S. garages and small shops will rust tools fast if you ignore them.

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When to Resharpen vs Replace End Mills

I treat resharpening like a cost decision, not a sentimental one.

Usually worth resharpening:

• Larger carbide end mills (½” and up)
• High‑value specialty cutters
• Standard profiles you use a lot

Usually better to replace:

• Small diameters (¼” and under) – resharpening costs more than a new tool
• Cheap import HSS where geometry is already poor
• Cutters with broken corners so deep they’d lose too much diameter

If surface finish drops off, cutting forces spike, or you see heavy flank wear but the tool isn’t chipped, that’s a solid resharpening candidate.

Inspecting Tools for Wear, Chipping, and Runout

Don’t wait for a crash to tell you a tool is bad.

• Visual check: Look for:
  • Dull or shiny “polished” land behind the cutting edge
  • Tiny chips on the corners or along the flute
  • Discoloration (blue/brown) from overheating
• Runout check:
  • Put the tool in a clean holder and clock it near the tip with a dial indicator.
  • For most manual mills, aim for under 0.001″ TIR at the tool tip.
• Shell mills and face mills:
  • Inspect inserts for chipped corners and worn edges.
  • Check pockets for chips and burrs that prevent proper seating.

Labeling and Tracking Tool Life

A simple tracking system saves carbide and time.

• Mark common cutters with a Sharpie or label:
  • Material used on (AL, CRS, 304, etc.)
  • Number of “jobs” or hours roughly run
• Keep a basic spreadsheet or notebook:
  • Tool size, material, coating
  • Typical feeds/speeds
  • When you notice finish going bad or chatter increasing
• Color‑code drawers or racks for “new,” “used,” and “needs sharpening.”

Safe Handling and Storage of Carbide and Coated Tools

Carbide is tough in the cut but brittle in your hand.

• Always grab carbide end mills by the shank, not the flutes.
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Mild Steel (1018)	80–120	250–400	3–4 flute, coated carbide works best
Stainless (304/316)	50–80	150–250	Keep feed up, avoid rubbing
Cast Iron	60–100	250–400	Usually dry, very abrasive

For deeper detail on tool behavior and cutter styles, I recommend checking a solid milling cutter types and applications guide.

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Recommended Chip Load by End Mill Diameter (Carbide, Side Milling)

These are safe starting chip loads per tooth for typical shop work:

Tool Diameter	Aluminum (in/tooth)	Steel (in/tooth)	Stainless (in/tooth)
1/8″ (0.125)	0.001–0.0015	0.0007–0.001	0.0006–0.0009
1/4″ (0.250)	0.0015–0.003	0.001–0.002	0.0008–0.0015
3/8″ (0.375)	0.003–0.005	0.002–0.003	0.0015–0.0025
1/2″ (0.500)	0.004–0.007	0.0025–0.004	0.002–0.0035

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• On a small benchtop mill, drop another ~20–30% until you know the machine’s limits.

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Under-tightening ruins tools. Over-tightening ruins collets and nuts. I keep this as a best-practice range:

• ER16 collet nut: 45–60 ft-lb
• ER32 collet nut: 90–130 ft-lb
• ER40 collet nut: 130–160 ft-lb
• R8 collet drawbar (manual mill): snug plus about 1/8 turn with a short wrench – don’t gorilla it

Tips:

• Always use the correct ER spanner wrench.
• Make sure collet, nut, and tool shank are clean and dry before tightening.

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Coating Temperature and Application Quick View

Use coatings where they actually help:

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TiN	~900°F	General steel, mild work	Basic, older tech
ZrN	~1,100°F	Aluminum, non-ferrous	Great to avoid built-up edge
AlTiN	~1,400°F	Steel, hardened steels	Needs heat; avoid flood in aluminum
TiSiN	~1,800°F	High-speed steel cutting, hard materials	Good for aggressive cuts
AlCrN	~1,650°F	Steel, stainless, high-temp alloys	Tough, good wear resistance

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Checklist: Must-Have Tooling for a New Milling Machine

For a basic but capable US small-shop or garage setup, I recommend:

Cutting Tools

• Basic set of carbide end mills:
  • 1/8″, 1/4″, 3/8″, 1/2″ in 2-flute (aluminum) and 3–4 flute (steel)
• A couple of roughing end mills in 3/8″ and 1/2″
• One face mill or fly cutter for surfacing
• A few spot drills and center drills

Toolholding

• Proper R8 or BT/CAT toolholders (depending on your spindle)
• ER collet chuck with a starter ER collet set
• Basic R8 collet set (if on a manual Bridgeport-style mill)

Workholding

• Kurt-style milling vise (6″ for full-size knee mill, 4″ for benchtop)
• Clamping kit with step blocks, strap clamps, studs, and nuts
• Set of 1-2-3 blocks and parallels

Setup and Measurement

• Edge finder or electronic probe
• Dial test indicator with mag base or clamp
• Calipers and a 0–1″ micrometer

Print these quick references and tape them inside a cabinet door near the mill. When everyone in the shop uses the same baseline numbers and checklists, your tooling lasts longer and your parts get a lot more consistent.