Joined: 01 Jun 2005
Posts: 220
Location: Melbourne, Victoria
Got some pictures
16" Wheelbarrow wheel
16" Wheelbarrow wheel on its side to show that wheel sticks out alot further than the centre
Just the hub with the bearings removed
Ratchet with the sprocket
Ratchet & sprocket on top of the hub
Ratchet & sprocket on top of wheel, showing how little clearance there is and why it needs to be offset
Also got some dimensions:
16" Wheel barrow wheel - 35mm internal dia and 38mm outside dia for the shaft
Ratchet has same PCD (pitch circle diameter) as the inside of the 80 tooth sprocket from Oatley. It has a thread at around 34mm dia, apparently it will thread onto the threaded section of the back wheel of a push bike.
Thu May 10, 2012 8:13 pm
Andrew W
Joined: 01 Jun 2005
Posts: 220
Location: Melbourne, Victoria
After speaking to Glen the other day, he suggested I don't need the 19/20mm shaft. He suggested I just get the 35mm shaft (just after the welded ratchet) turned down to 19/20mm and mount the bearings on that.
Just a question, since the bearings is butting straight against the edge of the shaft, will I have any problems with a stress concentrator ? and is this feasible to be made of steel ?
Looking good. Gotta love the seamless jump from 2009 to 2012. _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
Wed May 16, 2012 11:30 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
We'll you can always step it down with a taper on the shaft. Or use a 30mm bearing. Either way i don't think anything this side of a bus falling on top of it would break an axle that thick the wheels will buckle long long before that! _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Wed May 16, 2012 11:35 pm
Andrew W
Joined: 01 Jun 2005
Posts: 220
Location: Melbourne, Victoria
@Marto - I gave up on using the 16" wheels and tried the 10" trolley wheels and still didn't get anywhere (still needed the sprocket to be offset from the hub). I put the project on the back burner a couple of years ago and only just decided to bring it back and use live axles instead of dead.
@Glen - Thanks for your help.
Forgot to mention that the ratchet has a thread on the inside, not really sure what it is (~34mm). Apparently it is supposed to screw onto the rear wheel of a push bike (according to Oatley).
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the wheels will buckle long long before that!