Jet BD-920W Operating Instructions Manual

Also see for BD-920W: Brochure Brochure Operating instructions and parts manual

Contents

Jet BD-920W Operating Instructions Manual Manual pdf 5 page image

76.6 Turning with auto feedThree automatic longitudinal feedsare readily available by selection onthe gearbox handle. Further feedrates are possible by differentchange gear setups.By moving lever (A, Fig 9) upward,the automatic feed is engaged.Fig 9The correct feed depends on thematerial to be cut, the cuttingoperation, the type of tool, therigidity of the work piecechucking, the depth of cut and thedesired surface quality.For example:OD-turning mild steel of 20mmdiameter with an HSS tool at 350RPM and with rigid chucking.Change gear setup as shown (Fig10).Fig 10Stock removal and roughing cut:Depth of cut 1,5mmFeed per revolution 0,15mm(change gear box position III)Finishing cut:Depth of cut 0,5mmFeed per revolution 0.07mm(change gear box position II)Micro finishing and calibrationcut:Depth of cut 0,2mmFeed per revolution 0.04mm(change gear box position I)When roughing big diametersreduce the depth of cut!6.7 Thread cuttingThreading is performed in multiplepasses with a threading tool.Each depth of cut should be about0,2mm and become less for thefinishing passes.A) To cut inch and metric threadsSet the machine up for the desiredthreading pitch and first depth of cut.Engage the halve nut (A, Fig 11).The halve nut must be engagedduring the entire threading process.- Start the machine at the lowestspindle speed.- When the tool reaches the end ofcut, stop the motor and at the sametime back the tool out of the part sothat it clears the thread (Attentioninertia: Stop the motor in time)- Reverse the motor direction toallow the cutting tool to travel backto the starting point.Repeat these steps until you haveobtained the desired results.Caution:The spindle direction may not bechanged during machineoperation!Fig 11B) To cut metric threads withpitch 0,4/ 0,5/0,75/0,8/1 /1,5 /2 /3mm:On these pitches the threading dial(B, Fig 11) can be used.The halve nut can be opened at theend of cut, rather than the motorbeing stopped and reversed.The halve nut may only be engagedat any graduation match (every12mm on the lead screw).6.8 Drilling operationUse a drill chuck with MT 2 arbor(option) to hold centring drills andtwisted drills in the tailstock.Fig 12For recommended speeds refer tosection 6.4To eject the drill chuck, fully retractthe tailstock quill.7. Setup and adjustmentsGeneral note:Setup and adjustment work mayonly be carried out after themachine is protected againstaccidental starting by pulling themains plug.7.1 Change gear setupUnplug the machine from the powersource.Loosen the locking screw on thepulley cover, then open the cover.-Loosen screw (1, Fig 13)-Unscrew bolt (2), remove washer(3) and gear (6)-Loosen bolt (7) to allow movement.-Loosen nut (5), remove washer (4)and gear (8)Fig 13Reassemble with desired gear setup