September 02, 2005
Bevel Gear
 After a long absence - noted in the forum I'm back with more Workshop Notes. I'm designing a model that needs a ninety degree rotation in drive direction so I am trying to construct a bevel gear. Pictured here is an early prototype. the lower gear with have fifteen teeth, the upper one twelve. The teeth are constructed in groups of four, one cut off for the larger gear. It seems to work as is but I am worried about teeth bending, rectangular tubes are obviously not a rigid structure. Next step is to construct a complete pair of gears and mount them into a frame, see if they work. I am slightly uneasy about the shape of the gear. I wonder if it is not really a card project. I have simply taken the shape of bevel gears from their metal counterparts and recreated it in card, perhaps I should be looking for a different solution more suited to the material. It reminds me of the construction of Iron Bridge. The bridge was the first to be constructed from iron. The arch shape was designed by engineers more used to using wood, so, using their well know techniques, parts were joined using dovetail joints... |
Comments
A long fan of your work, Rob, this site is spectacular. It gives your craft the honor it deserves - presents it in a really professional light, and shows how impressive it is.
Mucho congratuloso!!! :)
(BanjoMan has his bags packed. hehehe)
Linda(Tee)
Sunnyvale, CA
would a round tube (in this case, cone) pushed inside the gear tooth stiffen it up?
Posted by: john tobako at September 15, 2005 04:20 PMJohn, I put a card disk top and bottom of each gear, the result is a suitably rigid gear and a place to glue the axle.
Rob