{"product_id":"screw-pitch-gauge","title":"Screw pitch gauge, metric and imperial","description":"\u003cp\u003eYou have a screw. You need another one like it. A caliper gives you the diameter, and the diameter is only half the answer - M3 comes in 0.5 and 0.35, and a 0.35 screw in a 0.5 hole strips both.\u003c\/p\u003e\n\u003cp\u003eTwo fans of steel leaves, each cut to a thread profile and stamped with its pitch. The 60 degree set covers metric. The 55 degree set covers British and pipe threads.\u003c\/p\u003e\n\u003ch3\u003eHow you use it\u003c\/h3\u003e\n\u003cp\u003eHold a leaf against the thread and look at the light behind it. The right leaf disappears into the thread with no gap anywhere along its length. The wrong one touches at one end and stands off at the other, and the gap is obvious the moment you see the correct one.\u003c\/p\u003e\n\u003cp\u003eThat is also how you check a tap before you cut with it, and how you find out what a thread in a casting is before you order screws for it.\u003c\/p\u003e\n\u003ch3\u003eWhy both angles\u003c\/h3\u003e\n\u003cp\u003eMetric threads are cut at 60 degrees. British Standard Whitworth and BSP pipe threads are cut at 55. A 60 degree leaf will sit in a 55 degree thread and look almost right, which is worse than looking wrong. Having both in one tool means you find out.\u003c\/p\u003e\n\u003ch3\u003eWhere it stops\u003c\/h3\u003e\n\u003cp\u003eCarbon steel, not stainless. It will rust if you leave it damp. Oil it.\u003c\/p\u003e\n\u003cp\u003eIt tells you the pitch, not the diameter and not the class of fit. Pair it with the caliper - pitch from here, diameter from there, and then you know what to order.\u003c\/p\u003e\n\u003cp\u003eThe leaves are thin and stamped. Prying with one bends it, and a bent leaf reads wrong.\u003c\/p\u003e","brand":"Mikrabench","offers":[{"title":"Default Title","offer_id":47512876810431,"sku":null,"price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0760\/5826\/3743\/files\/S77b1389a6247496da42b5b44fbd5473aO.webp?v=1789875417","url":"https:\/\/arvonelle.com\/products\/screw-pitch-gauge","provider":"ARVONELLE","version":"1.0","type":"link"}