J.W. DONCHIN CO. 4841-43 W. Chicago Ave. Chicago, IL 60651-3224 Ph: 773-261-2182 Fax: 773-261-2867 Sales@jwdonchin.com www.jwdonchin,com CALIPERS, DIVIDERS Contents Page Description Range 357 CALIPERS, DIVIDERS 358 Toolmakers Spring-Type Calipers and Dividers with round legs and solid nut Nos. 274, 275, 277 Series 3, 6 (75, 150mm) Fay Spring-Type Calipers and Dividers with heavy square legs and quickspring or solid nut Nos. 74, 75, 77 Series 6 (150mm) 359 Yankee Spring-Type Calipers and Dividers with flat legs and quick-spring or solid nut Nos. 73, 79, 83 Series 4, 6, 8, 12 (100, 150, 200, 300mm) 360 Yankee Spring-Type Hermaphrodite Calipers with quick-spring or solid nut No. 43 Series Thread Calipers Nos. 179 and 184 361 Firm-Joint Hermaphrodite Calipers No. 243 Hermaphrodite Calipers Firm-Joint No. 563 Lock-Joint with fine-adjustment No. 42 Series 362 Improved Firm-Joint Calipers No. 26 Series (Outside) No. 27 Series (Inside) 363 Lock-Joint Calipers with fine-adjustment No. 38 Series (Outside) No. 39 Series (Inside) 6 (150mm) 6 (150mm) 6 (150mm) 6 (150mm) 6, 8 (150, 200mm) 6-36 (150-900mm) 6-24 (150-600mm) 6-24 (150-600mm) 6-24 (150-600mm) 364 Lock-Joint Transfer Type Calipers with fine-adjustment No. 36 Series (Outside) No. 37 Series (Inside) 365 Divider Ball Points with holder No. 88 Series 6-24 (150-600mm) 6-24 (150-600mm) 4, 7 1/2 (100, 188mm) 366 Improved Trammel Heads with divider points, pencil socket No. 50 Series 367 Trammel Heads, Divider Points, Attachments No. 59 Series 368 Steel Beam Trammels and Attachments No. C251 Series 10 1/2-20 (260-500mm) Beams
This section concerns so-called skill tools. A pair of calipers (in common terms, one caliper) is one of the oldest types of comparison measuring tools. They depend on feel to measure a part, transfer the dimension to a precision rule, micrometer or slide caliper, and get a good reading. This involves skill and experience. If used properly, calipers can measure to at least.004 or 0.01mm. Measuring with a caliper requires as light a touch as possible because most comparisons are made with rules, where the caliper is laid against the graduations, without the contacts touching anything. Calipers and dividers are offered in two general designs: spring-type and firm-joint. Spring-type calipers are tensioned against the screw adjustment, while the firm-joint is held by friction. Caliper sizes refer to the distance from the fulcrum to the end of the leg. The measuring capability of spring-type calipers and dividers is approximately the same as the size. The measuring capability of firm-joint and lock-joint calipers is approximately one-third more than the size. Caliper points are not hardened because they only compare measurements. The contact points can be easily shaped in whatever manner desired. All divider points however, are hardened. Dividers and trammels are usually set to rule graduations and can be set more accurately than calipers.
Toolmakers Spring-Type Calipers and Dividers with round legs and solid nut Nos. 274, 275, 277 Series 3, 6 (75, 150mm) Starrett Toolmakers Calipers and Dividers are the finest tools of their type. Designed for toolmakers and all good mechanics who require finer adjustment and better balance so a more sensitive feel can be obtained. Precision made to rigid Starrett standards throughout. The fulcrum stud is hardened and the bearing surfaces of the legs are large enough to prevent any side deflection. The bow spring is strong and flexible, and the adjustment is centrally located in the legs to assure smooth action. Left to right: No. 274-6 Inside Caliper, No. 275-6, Outside Caliper and No. 277-6 Divider. Size and Approx. Capacity Inside Calipers Outside Calipers Dividers Catalog No. EDP No. Catalog No. EDP No. 3 75mm 274-3 51301 275-3 51305 277-3 51309 6 150mm 274-6 51303 275-6 51307 277-6 51311 Fay Spring-Type Calipers and Dividers with heavy square legs and quickspring or solid nut Nos. 74, 75, 77 Series 6 (150mm) Starrett Fay Calipers and Dividers feature exceptionally rugged construction. The legs are made from heavy square stock, machined to a smooth taper. The fulcrum stud is hardened and has a large bearing surface to prevent side deflection of the legs. The bow spring is both strong and flexible, and the adjustment screw is centrally located in the legs to assure smooth action. Furnished in either spring nut or solid nut models. The Starrett quick-adjusting automaticclosing spring nut is designed for making quick, positive adjustments. The threads of the nut firmly engage the screw at the slightest pressure from the leg. When the pressure is withdrawn, the nut automatically releases itself, sliding freely over the screw. Inside Calipers Size and Approx. Capacity Solid Nut Quick-Spring Nut Catalog No. EDP No. 6 150mm 74A-6 50349 74B-6 50348 Outside Calipers 6 150mm 75A-6 50355 75B-6 50354 Dividers Left to right: No. 74B-6 Inside Caliper, No. 75B-6 Outside Caliper, No. 77B-6 Divider Below: Quick-adjusting spring nut. 6 150mm 77A-6 50361 77B-6 50360 358
Yankee Spring-Type Calipers and Dividers with flat legs and quick-spring or solid nut Nos. 73, 79, 83 Series 4, 6, 8, 12 (100, 150, 200, 300mm) Starrett Yankee Calipers and Dividers are made from a high-grade steel and wellfinished. The legs are made of flat stock and are very durable. The fulcrum stud is hardened and has a smooth bearing surface. The bow spring, although flexible, is exceedingly strong to assure reliability. All sizes are available with either spring nut or solid nut. The Starrett quick-adjusting automatic-closing spring nut is designed for making fast, positive adjustments. The threads of the nut firmly engage the screw at the slightest pressure from the leg. When the pressure is withdrawn, the nut automatically releases itself, sliding freely over the screw. This feature saves time in opening and closing. Quick-adjusting spring nut makes fast, accurate settings. Left to right: No. 73B-6 Inside Caliper, No. 79A-6 Outside Caliper and No. 83A-6 Divider. Inside Calipers Size and Approx. Capacity Solid Nut Quick-Spring Nut Catalog No. EDP No. 4 100mm 73A-4 50334 73B-4 50335 6 150mm 73A-6 50336 73B-6 50337 8 200mm 73A-8 50338 73B-8 50339 12 300mm 73A-12 50342 73B-12 50343 Outside Calipers 4 100mm 79A-4 50364 79B-4 50365 6 150mm 79A-6 50366 79B-6 50367 8 200mm 79A-8 50368 79B-8 50369 12 300mm 79A-12 50372 79B-12 50373 Dividers 4 100mm 83A-4 50376 83B-4 50377 6 150mm 83A-6 50378 83B-6 50379 8 200mm 83A-8 50380 83B-8 50381 12 300mm 83A-12 50384 83B-12 50385 359
Yankee Spring-Type Hermaphrodite Calipers with quick-spring or solid nut No. 43 Series 6 (150mm) These calipers have the same overall design and finish features as our Yankee calipers. One leg is bowed for clearance and capacity. The fine-adjustment screw allows for close setting accuracy. This tool will scribe lines parallel to outside edges easily and consistently. Quick-adjusting spring nut makes fast, accurate settings. No. 43A-6 with solid nut. Size and Approx. Capacity Solid Nut Quick-Spring Nut Catalog No. EDP No. 6 150mm 43A-6 66575 43B-6 66576 Thread Calipers Nos. 179 and 184 6 (150mm) Starrett Thread Calipers are designed for measuring screw threads. The points of the No. 179 are tapered for measuring outside threads, and the points of No. 184 are shaped for inside threads. These calipers are made from a high-grade steel and wellfinished. The fulcrum stud is hardened and has a smooth bearing surface. The bow spring, although flexible, is exceedingly strong to assure reliability. Furnished with solid nut only. Left, Outside Thread Caliper No. 179-6; right, Inside Thread Caliper No. 184-6. Size and Approx. Capacity Inside Caliper Outside Caliper Catalog No. EDP No. 6 150mm 184-6 50674 179-6 50669 360
Firm-Joint Hermaphrodite Calipers Starrett Hermaphrodite Calipers are used in layout work for locating and testing centers, laying off distances from an edge, etc. We offer a complete choice from which machinists and toolmakers can select to best suit their requirements. The rugged, properly shaped legs are made of finely finished, high-grade steel. Sizes listed are the lengths of the legs. Actual measuring capacity is approximately one-third greater than the leg size. No. 243 6 (150mm) This caliper features a round, adjustable leg and an improved firm-joint, which allows the joint to be adjusted at any tension. The leg that holds the adjustable point is offset. Left, reverse side of No. 243-6; right, front side. *NOTE: Actual capacity is one-third greater than the listed size. 6 150mm 243-6 51143 Hermaphrodite Calipers Firm-Joint No. 563 6 (150mm) Lock-Joint with fine-adjustment No. 42 Series 6, 8 (150, 200mm) No. 563 This caliper has a round, adjustable point held by a straight leg. An improved, firm-joint feature permits the joint to be adjusted at any desired tension. No. 42 Series These calipers have an adjustable point, locking joint and fine-adjustment feature for close measurements. After the legs have been set to approximate size and the joint locked, the final adjustment is made by a few turns of the knurled adjusting nut. *NOTE: Actual capacity is one-third greater than the listed size. Left, No. 563-6 Firm- Joint. To the right, No. 42-6 front side (left) and reverse side (right). No. 563 Firm-Joint 6 150mm 563-6 52572 No. 42 Series Lock-Joint 6 150mm 42-6 50263 8 200mm 42-8 50264 361
Improved Firm-Joint Calipers No. 26 Series (Outside) 6-36 (150-900mm) No. 27 Series (Inside) 6-24 (150-600mm) Starrett Firm-Joint Calipers have an improved joint designed so the tension can be adjusted as desired. After adjustment has been made, the tension will not change with the opening and closing of the legs. The legs are made from a high-grade steel, are ruggedly constructed and are wellfinished. The sizes listed are the lengths of the legs. Their actual measuring capacity is about one-third greater than the given size of the legs; for example, the 36 size will caliper a 46 diameter. Left, No. 26-6 outside model; right, No. 27-6 inside model. No. 26 Series Outside Calipers 6 150mm 26-6 50186 12 300mm 26-12 50189 18 450mm 26-18 50190 24 600mm 26-24 50191 36 900mm 26-36 50192 No. 27 Series Inside Calipers 6 150mm 27-6 50193 12 300mm 27-12 50196 18 450mm 27-18 50197 24 600mm 27-24 50198 *NOTE: Actual capacity is one-third greater than the listed size. 362
Lock-Joint Calipers with fine-adjustment No. 38 Series (Outside) 6-24 (150-600mm) No. 39 Series (Inside) 6-24 (150-600mm) These calipers feature a joint that can be quickly and firmly locked by a partial turn of the large knurled disc. A spring washer under the disc maintains proper tension of the legs when the joint is unlocked. These calipers are also provided with an adjusting screw to permit fineadjustments for close measurements. After the legs have been set to approximate size and the joint locked, the final adjustment is made by a few turns of the knurled adjusting nut. The legs are made of a high-grade steel and well shaped. They are ruggedly constructed and nicely finished. The sizes listed are leg lengths. Their actual measuring capacity is about one-third greater than the given size of the legs. Left, No. 38-6 outside model; right, No. 39-6 inside model. No. 38 Series Outside Calipers 6 150mm 38-6 50253 12 300mm 38-12 50254 24 600mm 38-24 50256 No. 39 Series Inside Calipers 6 150mm 39-6 50257 12 300mm 39-12 50258 24 600mm 39-24 50260 *NOTE: Actual capacity is one-third greater than the listed size. 363
Lock-Joint Transfer Type Calipers with fine-adjustment No. 36 Series (Outside) 6-24 (150-600mm) No. 37 Series (Inside) 6-24 (150-600mm) One of the handiest and most versatile calipers ever made Starrett Lock-Joint Transfer Calipers have three key features a transfer arm, fine-adjustment screw, and locking joint. The transfer arm makes it possible to transfer measurements from the inside of chambered cavities, over flanges and other places where it is necessary to move the legs after they have been set to size. Simply lock the joint, loosen the transfer arm binding nut and swing the leg out or in to clear the obstruction. Then move it back against the transfer arm stop and the exact size can then be transferred to a rule or gage. The adjusting screw permits close adjustments for fine measurements. After the legs have been set to approximate size and the joint locked, the final adjustment is made by a few turns of the knurled adjusting nut. The joint can be quickly and firmly locked by a partial turn of the large knurled disc. A spring washer under the disc maintains proper tension of the legs when the joint is loosened. The legs are made from a high-grade steel and are well-shaped. They are ruggedly constructed and nicely finished. The sizes listed are the length of the legs. Their actual measuring capacity is about one-third greater than the size of the legs. Left, No. 36-6 outside model; right, No. 37-6 inside model. Measuring outside dimension. Checking inside groove. No. 36 Series Outside Calipers 6 150mm 36-6 50245 12 300mm 36-12 50246 24 600mm 36-24 50248 No. 37 Series Inside Calipers 6 150mm 37-6 50249 12 300mm 37-12 50250 24 600mm 37-24 50252 *NOTE: Actual capacity is one-third greater than the listed size. 364
Divider Ball Points with holder No. 88 Series 4, 7 1/2 (100, 188mm) These accessories are used with dividers and trammels when it is necessary to use a hole as a center point for layout, scribing and measuring. The ball point is placed in the hole and bears against the edge, forming a seat for the divider leg or tram. The set consists of either a 4 or 7 1/2 (100 or 188mm) holder with four balls. They are not recommended for exceptionally close work because it is impossible to keep them exactly in the center of the hole. Complete set No. 88A including holder and four balls. Complete Sets Holder Balls Fits Starrett Catalog Inch mm Inch mm Dividers No. EDP No. 4 100mm Four: Nos. 85A, 85C, 1/2 13mm No. 92 Series 88A 50410 7 1/2 188mm 3/4 19mm 1 25mm Nos. 85B, 85D, 1 9/16 40mm 85E, 85F 88B 50411 Individual Balls/Holders Size Fits Starrett Catalog Inch mm Description Dividers No. EDP No. 1/2 13mm 88C 72005 3/4 19mm Nos. 85A, 85C, 88D 72006 Ball Only 1 25mm No. 92 Series 88E 72007 1 9/16 40mm 88F 72008 4 100mm 88G 72009 7 1/2 188mm Holder Only Nos. 85B, 85D, 85E, 85F 88H 72010 365
Improved Trammel Heads with divider points, pencil socket No. 50 Series Used to measure the distance between points that are too great to be reached with dividers. The heads are die cast with black wrinkle finish and have hardened, forged steel divider points. The points screw into the heads, and the pencil socket accompanying each set of trammel heads can be used in place of either point. No. 50A has an adjustable point. Longer points (5 /125mm) are also available. A beam is not furnished with these trammels. The heads will accommodate a beam up to 3/8 (9.5mm) thick and 3/4 (19mm) wide. No. 50A Trammel Heads with points (adjustable point capability on right side head) mounted on beam (not furnished) for demonstration purposes. Pencil socket (lower left) can screw into a head in place of points if drawing (instead of scribing) is desired. Trammel Heads Point Size Inch mm Description Catalog No. EDP No. 3, 2 1/2 75, 63mm 3 75mm (Longer) Points Only (Adjustable) Includes 2 Heads, 2 Points, Pencil Socket Includes 2 Heads, 2 Points, Pencil Socket 50A 50268 50B 50269 5, 4 1/2 125, 113mm 2 Adjustable Points for Starrett 50CA 50270 No. 50A 5 125mm 2 Points for Starrett No. 50B 50CB 50271 366
Trammel Heads, Divider Points, Attachments No. 59 Series The No. 59 Series is very useful for laying out and scribing circles beyond the capacity of ordinary dividers. The trammel heads have a clamping device that firmly holds various attachments. The attachments consist of two sizes of caliper legs, 6, 9 1/2 (150, 238mm), two sizes of divider points 6,9 (150, 225mm) which are eccentric for close settings, and a set of four ball points with holder. The ball points with 6 (150mm) holder are for scribing circles from the center of any hole up to 1 1/2 (38 mm) in diameter. One of the large caliper legs features a joint operated by an eccentric thumb piece for fine adjustments. A pencil may be clamped in either head in place of the caliper legs or divider points. The heads will accommodate any size beam from 3/4-1 1/2 (19-38mm) in width. Since beam length requirements vary widely, and they are easy for the user to fashion, we do not furnish a beam. No. 59F Set, complete (beam not furnished). Description Catalog No. EDP No. 2 Trammel Heads, 2 Small Points (6 /150mm) 59A 50297 Set of 4 Ball Points and One Holder Only 59B 50298 Pair Small Caliper Legs Only (6 /150mm) 59C 50299 Pair Large Caliper Legs Only (9 1/2 /228mm) 59D 50300 Large Points Only (9 /225mm) 59E 50301 Complete Set: Nos. 59A, B, C, D, E 59F 50302 367
Steel Beam Trammels and Attachments No. C251 Series 10 1/2-20 (260-500mm) Beams A rigid, well-designed trammel for layout, scribing, and measuring distances and circles. The top of the beam is flattened so that when the trams are clamped in position, they will not turn from pressure on the points. The trams are held in place by spring friction, which prevents them from sliding when the nuts are loosened for setting. One tram has a fine-adjusting screw for the points. Each tram has a knurled swivel grip at the top that turns freely, making it very convenient to swing the tool when scribing circles. The 3 (75mm) points may be adjusted for length in the spring chucks and can be easily replaced with caliper legs or other attachments listed. The ball points with 3 (75mm) holder permit working from holes up to 1 1/2 (38mm) in diameter. A pair of 3 (75mm) caliper points is included with each trammel. J No. C251A. F H E Ideal for draftsmen, engineers, metalworkers for layout work, scribing and measuring Furnished with rigid steel beam 10 1/2 (263mm), 14 1/2 (360mm) or 20 (500mm) sizes Bright chrome finish for longer life, resistance to corrosion Highly versatile handy attachments available to extend range and measure Packed one in a box. Attractive, protective cases are available for trammels Nos. C251A, B, C. To order, add ZZ to catalog number. (Example: C251AZZ). Trammels Max. Max. Circle Scribing Dividing Range Diameter Range Beam Size Inch mm Inch mm 9 225mm 18 450mm 10 1/2 263mm C251A 51205 13 1/2 338mm 26 650mm 14 1/2 363mm C251B 51207 18 450mm 36 900mm 20 500mm C251C 51209 Individual Attachments Only D Attachments; D, E, J, H. Description Photo Key Catalog No. EDP No. Coupling, with Extra 20 (600mm) Beam (When used with No. C251C will scribe circle D C251D 51211 72 [1800mm] diameter) Ball Points and Holder E C251E 51212 Extra Caliper Points, Pair F 251F 51213 Steel Point and Socket (One) (Has.076 [1.9mm] hole diameter to hold leads) H C251H 51214 Needle Point (Chrome not available) (One) J 251J 51203 368
J.W. DONCHIN CO. www.jwdonchin.com Precision Measuring Equipment and Industrial Supplies since 1924. 4841 W. Chicago Ave. - Chicago, IL 60651 Phone: 773-261-2182 Fax: 773-261-2867 sales@jwdonchin.com J.W. Donchin Co. was established in 1924 and has been known world wide ever since. Customer Service is our Main Focus. We offer Expert Product Knowledge, Large Stocking Inventory and Competitive Pricing to assist you in locating and selecting the correct tool or product to fit your needs. (J.W. Donchin Co. is one of L.S. Starrett s largest stocking distributors.) Contact Information: Phone: 773-261-2182 Fax: 773-261-2867 Email: sales@jwdonchin.com Direct Access Links (View specific information, click on any of the following) Latest Website Updates: Website: Quotes: Latest Promos: Line Card (Product Lines & Mfg) Catalog / Promo / Pricelist Starrett Mitutoyo Fowler Brown & Sharpe