Posted by PAUL GIANNOSA at 2/2/2001 11:56 PM EST
Engineer on team #27, TEAM RUSH, from OSMTECH and TEXTRON AUTOMOTIVE CO..
In Reply to: Connecting hub sprockets to shafts
Posted by Patrick Dingle on 2/2/2001 7:17 PM EST:
: Does anyone know the most reliable way to connect a hub sprocket to a rotating shaft (no keyway)? We are planning to drill and tap the hub, and bolt slightly into the shaft. Is this reliable, or are there better ways?
: Thanks
: Patrick
HI PAT. JUST LOOKED @ SOME OF THE RESPONSES TO YOUR POST. I HAVE USED RAUL'S "DUTCHMAN" METHOD VERY SUCESSFULLY ON OUR WHEEL HUBS LAST YEAR AND I AM USING IT ON MY PLANETARY HUB WITCH REPLACES THE FRONT .5 OF THE DRILL MOTOR TRANS. THE DRILL SHAFT IS A CUSTOM ONE TURNED ON A LATHE FROM A GRADE 8 .75 BOLT. WE ARE ATTACHING A 16 TOOTH GEAR TO THE .472 DIA. SHAFT BY USING A DOWEL PIN. THE WAY I DID THAT ON LAST YEAR'S MACHINE WORKED REALLY WELL. WE NVR BROKE A GEAR OR SHAFT. WHAT I DO IS DRILL OUT THE 8/32 THREAD HOLE IN THE HUB TO .187 DIA. I DRILL AND TAP A LARGER 1/4-20 THD HOLE ON CENTER WITH THE .187 BORE. NEXT I BORE A .1875 DIA HOLE INTO THE .472 DIA DRILL SHAFT .200 DP. THIS IS SLIGHTLY LESS THAN HALF OF THE SHAFT. I CUT A .187 DOWEL TO FIT INTO THE GEAR AND SHAFT AND HOLD IT IN PLACE WITH THE 1/4-20 SET SCREW. I DON'T THINK YOU COULD GENERATE ENOUGH FORCE TO SHEAR A DOWEL PIN THAT IS ABOUT 45-55 ROCKWELL C. YOU ALSO MAINTIAN STRENGH IN THE SHAFT BY NOT BORING A HOLE COMPLETLY THROUGH. SORRY IF I'M A LITTLE WORDY. I CAN SEND YOU A AUTOCAD14 FILE SHOWING YOU GRAPHICALLY HOW I DO THIS. MY E-MAIL IS
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