{"product_id":"r8-shank-collet-chuck-spanner","title":"R8 ER32 Collet Chuck \u0026 Spanner — ER25 \/ ER32 \/ ER40 Options","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThis R8 ER32 collet chuck and spanner set gives your Bridgeport-style or mini mill spindle a precise, quick-change tool holding system. Each kit includes the R8-shank collet chuck body and a matched hook spanner wrench — the two items you need to put the ER collet system to work. Available in ER25, ER32, and ER40 to match your tooling diameter range. The R8 shank has a 7\/16\"-20 UNF drawbar thread for use in standard R8 spindles.\u003c\/p\u003e\n\u003ch2\u003eAvailable Options\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eER25 — R8 Shank:\u003c\/strong\u003e Collet range 1–16 mm (1\/32\"–5\/8\"). Fits standard ER25 collets. Includes ER25 hook spanner. Price: $42.95.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eER32 — R8 Shank:\u003c\/strong\u003e Collet range 2–20 mm (3\/32\"–3\/4\"). Fits standard ER32 collets. Includes ER32 hook spanner. Price: $52.95.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eER40 — R8 Shank:\u003c\/strong\u003e Collet range 3–26 mm (1\/8\"–1\"). Fits standard ER40 collets. Includes ER40 hook spanner. Price: $68.95.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eNote: ER collets are not included. Order the collet size that matches your tooling; see our ER collet sets listed separately.\u003c\/em\u003e\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eR8 shank with 7\/16\"-20 UNF drawbar thread — fits standard R8 spindles without modification\u003c\/li\u003e\n\u003cli\u003eHook spanner wrench included for each collet size — no separate wrench purchase required\u003c\/li\u003e\n\u003cli\u003eHardened and ground collet chuck body for concentricity at the collet seat\u003c\/li\u003e\n\u003cli\u003eChoice of ER25, ER32, or ER40 to match your end mill and drill bit diameter range\u003c\/li\u003e\n\u003cli\u003eDrawbar thread engagement verified to standard depth — addresses common fit issues seen with budget alternatives\u003c\/li\u003e\n\u003cli\u003eWorks with any brand of ER-standard collets (ER25, ER32, or ER40 as applicable)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank type:\u003c\/strong\u003e R8 taper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrawbar thread:\u003c\/strong\u003e 7\/16\"-20 UNF\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eER25 collet range:\u003c\/strong\u003e 1–16 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eER32 collet range:\u003c\/strong\u003e 2–20 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eER40 collet range:\u003c\/strong\u003e 3–26 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Alloy tool steel, hardened\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWrench included:\u003c\/strong\u003e Hook spanner matched to collet size (ER25, ER32, or ER40)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCollets included:\u003c\/strong\u003e None — order separately\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eDesigned for mills with R8 spindle tapers. Confirmed compatible with:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eBridgeport Series 1 \/ J-Head (R8 spindle)\u003c\/li\u003e\n\u003cli\u003eGrizzly G0731 \/ G0758 (R8 spindle)\u003c\/li\u003e\n\u003cli\u003eGrizzly G0704 (R8 spindle, mini mill)\u003c\/li\u003e\n\u003cli\u003eSieg X2 \/ SX2 \/ X3 (R8 spindle)\u003c\/li\u003e\n\u003cli\u003eHarbor Freight mini mill #44991 (R8 spindle)\u003c\/li\u003e\n\u003cli\u003eLittleMachineShop HiTorque mini mill (R8 spindle)\u003c\/li\u003e\n\u003cli\u003eAutobox MD100930 (R8 spindle)\u003c\/li\u003e\n\u003cli\u003ePrecision Matthews PM-25MV \/ PM-727 (R8 spindle)\u003c\/li\u003e\n\u003cli\u003eTormach PCNC 440 \/ 770 (R8 spindle)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eNot for use in lathe tailstocks, drill press spindles, or MT-taper machines. All listed machines confirmed in our compatibility database.\u003c\/p\u003e\n\u003cp\u003eUnsure if this fits your machine? Message us — we'll confirm before you order.\u003c\/p\u003e\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1 × R8-shank ER collet chuck body (ER25, ER32, or ER40 — per variant selected)\u003c\/li\u003e\n\u003cli\u003e1 × Hook spanner wrench matched to collet size\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eER collets are not included. Sold separately.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Do I need to buy collets separately?\u003c\/strong\u003e\u003cbr\u003eA: Yes. This kit includes the R8 collet chuck body and the hook spanner wrench. ER collets (ER25, ER32, or ER40) are sold separately. See our ER collet sets or our ER32 R8 chuck-with-collets bundle if you want everything in one order.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Which ER size should I choose — ER25, ER32, or ER40?\u003c\/strong\u003e\u003cbr\u003eA: Choose based on the largest tool shank diameter you plan to hold. ER25 covers up to 16 mm (5\/8\"), ER32 covers up to 20 mm (3\/4\"), and ER40 covers up to 26 mm (1\"). Most hobbyists running end mills up to 1\/2\" do fine with ER25; those running 3\/4\" shanks or face mills need ER32 or ER40.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: What drawbar thread does this R8 shank use?\u003c\/strong\u003e\u003cbr\u003eA: 7\/16\"-20 UNF — the standard thread for R8 tooling in Bridgeport-style mills. If your drawbar is metric (M12), this chuck will not thread in without an adapter; check your mill's drawbar before ordering.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Will this fit my lathe tailstock?\u003c\/strong\u003e\u003cbr\u003eA: No. This is an R8-shank tool holder for mill spindles only. Lathe tailstocks use MT2 or MT3 tapers, which are physically incompatible with R8 tooling. For lathe tailstock work, see our MT2 or MT3 drill chuck arbors.\u003c\/p\u003e\n\u003ch2\u003eWhy Buy from Us\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eShips from our US warehouse in Toledo, OH — typical 3–5 business day delivery, no overseas wait\u003c\/li\u003e\n\u003cli\u003eSpanner wrench included with every collet size — no separate wrench purchase, no sourcing mismatch\u003c\/li\u003e\n\u003cli\u003e30-day returns, no restocking fee — if it doesn't fit your machine, return it\u003c\/li\u003e\n\u003cli\u003eUS-based customer support — email us a photo of your spindle, we'll confirm fit before you order\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Autobox","offers":[{"title":"ER25","offer_id":46727476347017,"sku":"TJT-ER25-R8","price":42.95,"currency_code":"USD","in_stock":true},{"title":"ER32","offer_id":46727476379785,"sku":"TJT-ER32-R8","price":52.95,"currency_code":"USD","in_stock":true},{"title":"ER40","offer_id":46727476412553,"sku":"TJT-ER40-R8","price":68.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0762\/4923\/5593\/files\/e433e0cc64a84451663c7f7be8750eb6.webp?v=1778736588","url":"https:\/\/autoboxtoolworks.com\/products\/r8-shank-collet-chuck-spanner","provider":"AutoBoxToolWorks","version":"1.0","type":"link"}