b'Productive TimesBRUSHING AWAY BURRSB urrs on machined metal partsEND USER SOLUTION PROVIDERScome in a variety of shapes and sizes but have one thing in com- JR Precision &Bass Tool & Supply Inc. Brush Researchmon: They must be removed. Welding LLC 800-442-0042 Manufacturing Co. Inc.JR Precision & Welding LLC gen- 972-322-2718 www.basstool.com 323-261-2193erates light, medium and heavywww.brushresearch.comburrs when machining 4140 steel muzzle brakes. Removing the burrsRemove burrs from 4140 steel muzzle brakesis challenging, said James Mawazeb,CHALLENGE for firearms.director of operations and lead engi-neer at the Houston-based machine shop, which was founded in 2017. SOLUTION An abrasive nylon wheel brush.A muzzle brake, or compensator, is a device connected to the barrelglassbeads,buttheprocessesthat can be removed with a thumb-of a rifle or pistol to help control re- proved ineffective, Mawazeb said. nail and said large burrs cant be. coil and the rising of the barrel thatManually deburring light burrsThe largest burrs the shop sees are normally occurs after firing. Muzzlewith a hook-shaped deburring toolabout 3.175 mm (0.125") high.brakes utilize slots, vents, holes,and removing large burrs with aAdding to the challenge was that baffles or similar features to redi- Dremel rotary power tool outfittedthe bar stock JR Precision & Weld-rect a portion of propellant gaseswith a sander were effective but in- ing previously machined was from a to counter recoil. Burrs form on theefficient methods. supplier that sold only heat-treated oval-shaped gas ports of parts. We pumped out 500 parts within4140 steel bars, Mawazeb said. The Mawazeb said the shop initiallyabout 10 days, Mawazeb said,shop eventually switched to a sup-took additional passes with the cut- and it took us an extra six days justplier of annealed stock, which is ting tools that had been used toto deburr all those parts. Even aftereasier to machine and deburr.machine the parts. we got done with deburring them, IFor a solution, JR Precision & It never helped us remove any ofstill had to make sure every part wasWelding turned to Houston-based the burrs, he said. right. A lot of people consider me atool distributor Bass Tool & Sup-JRPrecision&Weldingnextstickler for that, but if you are goingply Inc., which suggested testing sought whether another companyto put your name on a product, youan abrasive brush with filaments could deburr the parts with alumi- have to make sure its right. angled down. He said results were num-oxide sandblasting or evenHe defined a light burr as oneunimpressive.JR Precision & WeldingA 4140 steel muzzle brake is shown before and after deburring.ctemag.com/cteguide.com61ProTimes.indd 61 3/16/20 5:02 PM'