{"product_id":"cobalt-drill-set-03-3","title":"Cobalt Drill Set, 0.5 to 3 mm — 10 pieces","description":"\u003cp\u003e\u003cstrong\u003eTen cobalt bits that stop exactly where the machine stops.\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eMost kits at this price ship a 19-piece set running 1 to 10 mm. It reads generously right up until you notice that this chuck closes at 4 mm and the motor is 30 watts, so two thirds of those bits would never turn in this machine. You would be paying for a nice box.\u003c\/p\u003e\u003cp\u003eThis set is 0.5 to 3 mm because that is the working range of the press you are putting them in.\u003c\/p\u003e\u003ch3\u003eWhat is actually in the pack\u003c\/h3\u003e\u003cp\u003eTen bits in five sizes, two of each: \u003cstrong\u003e0.5, 1, 2, 2.5 and 3 mm.\u003c\/strong\u003e We say five sizes rather than ten because a spare of each is the useful thing at this scale - fine bits break, and the one you break is always the one you needed.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-speed steel with 5 percent cobalt (M35).\u003c\/strong\u003e Cobalt is what you use when plain HSS goes blunt on the second hole - harder metals, stainless, anything that work-hardens. It is not M42, which is the next grade up and costs several times this.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStraight shank.\u003c\/strong\u003e Fits the 0.3 to 4 mm chuck directly, no adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e135 degree split point\u003c\/strong\u003e so they start where you put them instead of wandering.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eIf you need below 0.5 mm\u003c\/h3\u003e\u003cp\u003eBuy the carbide PCB bits instead. This set starts at 0.5 mm and we are not going to pretend otherwise - the very fine sizes are a different material and a different job.\u003c\/p\u003e\u003ch3\u003eCobalt versus the carbide PCB bits\u003c\/h3\u003e\u003cp\u003eDifferent jobs. The carbide micro bits are for circuit board holes - very fine, very brittle, very fast. These are for metal: slower, tougher, and they bend before they snap.\u003c\/p\u003e\u003cp\u003eIf you are drilling boards, buy the carbide. If you are drilling brass, aluminium, steel sheet or a watch plate, buy these.\u003c\/p\u003e\u003ch3\u003eWhere they stop\u003c\/h3\u003e\u003cp\u003eThe bits will cut harder material than the machine can push them through. On a 30 W press the honest limit in metal is nearer 2 mm than 3, whatever the bit is made of. Cobalt buys you edge life, not torque.\u003c\/p\u003e\u003ch3\u003eAbout the photographs\u003c\/h3\u003e\u003cp\u003eThese are the manufacturer's. Ours are not taken yet, and we would rather say so than let you assume otherwise.\u003c\/p\u003e\u003ch3\u003eDelivery on this item\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003e6 to 10 business days.\u003c\/strong\u003e These ship from stock, so they are faster than the machine.\u003c\/p\u003e","brand":"Mikrabench","offers":[{"title":"Default Title","offer_id":46207865028799,"sku":"MB-BIT-CO10","price":16.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0760\/5826\/3743\/files\/Sd4041dd0bf57483a9dd3a6ab84fccc25m.webp?v=1789521692","url":"https:\/\/arvonelle.com\/products\/cobalt-drill-set-03-3","provider":"ARVONELLE","version":"1.0","type":"link"}