Hole saw TPI chart: teeth per inch by material
Teeth per inch is the spec every bandsaw guide leans on, so people arrive at hole saws asking the same question: how many TPI for steel, for wood, for stainless. The answer works differently here, and the difference is the most useful thing on this page. In bi-metal hole saws, TPI is set by the product line, not by the diameter of the cup. Milwaukee prints one pitch, 3.5 TPI, on its entire HOLE DOZER range from the 5/8 in cup to the 6 in [1][2][3]. So there is no TPI-by-size table in any manufacturer catalog this build checked, and any chart that tells you a 3/4 in hole saw wants 6 TPI while a 2 in wants 4 is describing bandsaw practice, not hole saws. What does exist, verified against manufacturer pages and catalogs, is TPI by material: which pitch each brand builds for which job. That is the chart below, with every number sourced.
What TPI means on a hole saw
TPI counts teeth along one inch of the cutting rim. A constant pitch line repeats the same spacing all the way around and publishes a single number: 3.5, 5.5, 8. A variable pitch line alternates coarse and fine spacing and publishes a pair: 4/6 or 4.5/5.5. The purpose of varying the pitch is vibration control: uneven tooth spacing breaks up the harmonic rhythm of teeth hitting the work, which Starrett markets as NVP (New Variable Pitch) on its Deep Cut line [5] and Irwin describes as reduced noise and improved performance [11]. Bosch's Progressor design takes a related route, alternating tooth sizes rather than spacing [18].
One piece of geometry keeps the "by size" confusion alive: bigger cups carry more teeth only because their rim is longer. Tooth count is circumference times TPI, so a 2 in cup at 3.5 TPI carries about 22 teeth and the same cup in an 8 TPI line would carry about 50. That arithmetic is ours, labeled as such; no brand prints per-size tooth counts, which is itself telling.
The chart: TPI by material and job
| Material or job | Pitch to look for | Example lines |
|---|---|---|
| General purpose: wood, nail-embedded wood, plastics, sheet metal | 3.5 TPI | Milwaukee HOLE DOZER bi-metal, one pitch across 5/8 to 6 in [1][2][15] |
| Stainless and mild steel sheet, tube walls up to 3mm (1/8 in) | 5.5 TPI constant | Starrett Fast Cut, 41mm cutting depth [4][5][7] |
| Solid metal and tube walls over 3mm, wood up to 51mm | 4/6 variable | Starrett Deep Cut, 51mm depth [5][7] |
| Stainless and mild steel sheet on cordless drills | 8 TPI constant | Starrett CSC Cordless Smooth Cut, 13mm depth cap [6][8] |
| Sheet metal on impact drivers | 8 TPI | Bosch Edge Impact Tough [9][10] |
| General wood and metal, mixed DIY work | 4.5/5.5 variable | Irwin WeldTec bi-metal [11][12] |
| Fiberglass, ceramic tile, laminates, abrasive sheet | No teeth: grit edge | Lenox carbide grit hole saws [13][14] |
| Tile, stone, glass | No teeth: diamond edge | Lenox Diamond grit hole saws [13][14] |
Brand-line TPI reference, with corroboration status
Every row below was checked against at least two surfaces: the manufacturer's own pages or catalogs, plus an independent surface where one exists. Where a claim rests on the manufacturer alone, the row says so.
| Brand and line | TPI | Pitch type | Surfaces |
|---|---|---|---|
| Milwaukee HOLE DOZER bi-metal | 3.5 | Constant (one figure, line-wide) | Manufacturer product and kit pages [1][2][3] plus independent summary [15] |
| Starrett Fast Cut bi-metal | 5.5 | Constant | starrett.com and starrett.co.uk [4][5] plus HellermannTyton catalog [7] |
| Starrett Deep Cut bi-metal | 4/6 | Variable (NVP) | starrett.co.uk [5] plus HellermannTyton catalog [7] |
| Starrett CSC Cordless Smooth Cut | 8 | Constant | starrett.co.uk category page [6] plus dealer listing [8] |
| Bosch Edge Impact Tough | 8 | Constant | boschtools.com [9] plus dealer spec listing [10] |
| Irwin WeldTec bi-metal | 4.5/5.5 | Variable | irwin.com category pages [11][12]; no independent surface found, manufacturer only |
| LENOX Speed Slot bi-metal (T3) | Not published | Not stated | Two Lenox catalogs print full diameter tables with no TPI column [13][14] |
| LENOX dealer spec feeds | 5/8 to 18 (bogus) | Mis-parsed | Two dealer feeds print the arbor thread in the TPI field [16][17] |
Why pitch tracks the material
The pattern in the chart is consistent across brands: coarse and constant for general work, fine and constant for thin sheet, variable for thick stock. The manufacturers' own positioning explains each step. Starrett draws its line at 3mm of wall: Fast Cut's 5.5 TPI tooth form is specified for stainless and mild steel sheet and tubes up to 3mm, while Deep Cut's 4/6 variable pitch takes over for solid material and tube walls beyond 3mm, trading some speed for penetration and deeper 51mm reach [5][7]. Fine constant pitches show up wherever thin sheet is the whole job: Starrett's 8 TPI CSC line (depth capped at 13mm, recommended cut depth 3mm) and Bosch's 8 TPI Edge line both exist because a fine, even pitch shears a thin cross section cleanly without grabbing [6][9]. Milwaukee goes the other way for general construction: one coarse 3.5 TPI form it describes as the longest-life design in metal applications, cutting wood, wood with nails, plastics, and drywall with the same cup [1][3].
Where the material has no chip at all, pitch stops being a spec. Abrasive and hard-brittle materials call for edged cups instead of toothed ones: Lenox assigns fiberglass, ceramic tile, and laminates to tungsten carbide grit edges, and tile, stone, and glass to brazed diamond edges, with a best/better/good material matrix in its catalog [13][14]. A grit edge has no teeth, so asking its TPI is a category error. Our how to drill into tile page covers running those.
What Lenox publishes, and the 5/8 to 18 TPI artifact
Lenox sells more hole saws than almost anyone and publishes no TPI for them. That is a verified absence, not an oversight of this build: the master catalog's bi-metal Speed Slot table lists every diameter from 9/16 to 6 in with product numbers, pipe tap sizes, and arbor assignments, and no TPI column anywhere; the carbide grit and diamond tables repeat the pattern [13]. The Lowes-hosted Lenox hole saw catalog carries the same diameter tables plus selection and RPM guides, still with no tooth pitch [14]. Lenox does publish TPI selection guides, but for reciprocating and bandsaw blades, which is exactly where the by-material TPI habit comes from.
The absence creates a vacuum, and syndicated dealer feeds fill it with garbage. At least two retailers print "Teeth Per Inch: 5/8 to 18 TPI" on ordinary Lenox bi-metal cups [16][17]. That string is not a pitch range; 5/8-18 is the arbor thread on 1-1/4 in and larger cups, the same 5/8 in by 18 threads-per-inch designation documented on our hole saw arbor size chart. The spec feed drops the thread designation into the TPI field and the store renders it verbatim. No hole saw on the market has an 18 TPI rim. If a listing quotes a TPI range for a hole saw, treat the listing as broken and check the manufacturer's page for the line instead.
Speed matters more than pitch
For metal work, RPM ruins more hole saws than tooth count does. Lenox's own recommended-speed table for bi-metal saws drops steeply with both diameter and material, and stainless runs at half the speed of mild steel at every size [13]:
| Diameter | Mild steel | Stainless | Cast iron | Brass | Aluminum |
|---|---|---|---|---|---|
| 3/4 in | 460 | 230 | 300 | 600 | 690 |
| 1-1/2 in | 230 | 115 | 150 | 300 | 345 |
| 2 in | 170 | 85 | 115 | 230 | 255 |
| 3 in | 115 | 55 | 75 | 150 | 170 |
Those are Lenox's suggested RPMs [13]; Starrett's speed bulletin prints 165 RPM mild and 85 RPM stainless for the same 2 in size, close enough to confirm the shape of the curve rather than any single number being gospel. The full speed story, including the wood side where hole saws run fast, is our drill speed chart.
Quick answers
- Is there a TPI chart by hole saw size? No. In bi-metal hole saws TPI belongs to the product line, not the diameter: Milwaukee prints 3.5 TPI on every HOLE DOZER from 5/8 to 6 in, and Lenox's diameter tables carry no TPI column at all. Chart TPI by material instead.
- What TPI for stainless steel? 5.5 to 8: Starrett Fast Cut 5.5 constant for sheet and tube to 3mm, Starrett CSC 8 constant for cordless sheet work, Bosch Edge 8 for impact drivers. And run it slow, about 85 RPM for a 2 in cup.
- What TPI for wood? Coarse general-purpose pitches: Milwaukee 3.5, Irwin 4.5/5.5. Every bi-metal saw cuts wood; speed control and plug clearing matter more than pitch.
- Why does a listing show 5/8 to 18 TPI? A mis-parsed spec feed: 5/8-18 is the arbor thread on larger cups, dropped into the TPI field. No hole saw has an 18 TPI rim.
Related guides
Also on this site: the hole saw size chart for which diameter your job needs, the hole saw arbor size chart for the two cup threads (including the 5/8-18 that dealer feeds mis-print as TPI), and hole saw pilot bit sizes for the center drill. For how fast to run each cup in each material, the drill speed chart and the drill press speed chart carry the RPM ladders. For picking the tool class rather than the tooth pitch: drill bits by material, how to drill through metal, and step drill bit sizes for thin sheet holes that need a cone instead of a saw.
Sources
- Milwaukee Tool, 3-1/2 in HOLE DOZER Bi-Metal Hole Saw (49-56-0193) product page, "new 3.5 TPI tooth design": milwaukeetool.com
- Milwaukee Tool, 5/8 in HOLE DOZER Bi-Metal Hole Saw (49-56-9603) product page, 3.5 TPI at the smallest size in the line: milwaukeetool.com
- Milwaukee Tool, 19PC HOLE DOZER Bi-Metal Hole Saw Kit (49-22-4035), kit-wide 3.5 TPI claim with the full size list: milwaukeetool.com
- Starrett, hole saws category page: Fast Cut 5.5 TPI constant pitch, Deep Cut NVP variable pitch: starrett.com
- Starrett UK, hole saw design article: Fast Cut 41mm height, constant 5.5 TPI; Deep Cut 51mm, variable 4-6 TPI (NVP): starrett.co.uk
- Starrett UK, CSC Cordless Smooth Cut category page: 8 TPI constant pitch, 13mm depth cap, recommended cutting depth 3mm, stainless and mild sheet: starrett.co.uk
- HellermannTyton Electrical Installation catalog, Starrett hole saw section: Fast Cut 5.5 TPI/25mm tooth form, 41mm depth; Deep Cut 51mm depth for material over 3mm (independent distributor catalog): manualzz.com mirror
- Vachri Tools, Starrett CSC Cordless Smooth Cut 24mm dealer listing, constant 8 TPI and 13mm depth: vachri-tools.com
- Bosch, Edge Impact Tough Hole Saw Set page: "Bi-Metal 8-TPI teeth, engineered for optimal cutting in sheet metal": boschtools.com
- 1Top Tools, Bosch Edge 3/4 in Impact Tough hole saw HTW34 dealer listing printing Teeth Per Inch 8: 1toptools.com
- Irwin, hole saws section: "patented Weldtec 4.5/5.5 variable tooth design": irwin.com
- Irwin, hole saws and mandrels accessories page, same WeldTec 4.5/5.5 variable tooth claim: irwin.com
- LENOX master catalog 209205012: bi-metal Speed Slot diameter tables 9/16 to 6 in (no TPI column), hole saw selection guide, and recommended RPM tables by material: Lenox catalog PDF
- LENOX Hole Saws and Accessories catalog (Lowes-hosted PDF): diameter tables, selection guide, RPM guide, no tooth pitch anywhere: pdf.lowes.com
- Real Buyer Experiences, hole saws explained (independent): Milwaukee HOLE DOZER 3.5 TPI constant, Starrett Fast Cut 5.5 constant, Deep Cut variable: realbuyerexperiences.com
- MyToolStore, Lenox 3003232L 2 in Speed Speed Slot listing printing "Teeth Per Inch: 5/8 to 18 TPI" (the mis-parse example): mytoolstore.com
- Contractor Tool Supply, Lenox 3002424L 1-1/2 in listing printing the same "5/8 to 18 TPI" field: contractortool.com
- Bosch, Bi-Metal Hole Saws (M42) category page: Progressor alternating tooth size design for wood, metal, plastic: boschtools.com