spinningmagnets wrote:... Including my 12-volume set of "Understanding a Womans Mind" (sadly, its in Latin...
gtadmin wrote:spinningmagnets wrote:... Including my 12-volume set of "Understanding a Womans Mind" (sadly, its in Latin...
and in an ink invisible to the male eye ...
spinningmagnets wrote:I've been told by a friend I will likely only get 15-MPH (24-kph) from a 250-kV motor-winding at 22V with a 1" diameter roller on a 26" wheel (I guess we'll see).
spinningmagnets wrote:Found an electric rear-wheel friction-drive with separate motor and roller from 1899 by John Schnepf, (So I'm only 111 years late to the game. Thanks for the pic, Roni). I notice it uses an off-the-shelf concave pulley wheel as the roller (recently suggested by paultrafalgar http://endless-sphere.com/forums/viewto ... 90#p183070).
It is shockingly similar to our modern systems
I have often made a black felt marker dot on aluminum, then gently scratched an X onto it in a precise spot with the steel caliper tips (a professinal machinist would cringe, but the caliper tips are just fine). I place a dent into the center of the X with a sharp pokey-device made for that ("sharp pokey device" is a technical term I learned from an engineer in the aerospace industry), and the dent keeps the small pilot drill bit from wandering.
I use a 3/16" pilot, as its the smallest one I found with three flats on the shank. Drill slow, stop to clear shavings often, and use lubricant (insert joke here). Once the pilot hole is complete, a larger bit can finish the job in the precise spot you wanted a large hole.
spinningmagnets wrote: and I'm told the Starley "safety bicycle" of 1885 was a very big hit (in spite of the really weak front "spoon" brake).
spinningmagnets wrote:It is shockingly similar to our modern systems
Yes! that was my first thought, too. I thoroughly enjoyed Miles' post about old bicycle inventions, and there being nothing new. I have been told that most cars before the 1920's were purchased for cash, rather than making payments. It was suggested that the financing was one of several reasons the bare-bones Model-T (with ultra-low price) was so successful at the time.
Its easy to forget that before WW-one (1914-17), a bicycle was a major purchase, and a patent for a desirable bike invention had a very wide market. The penny-farthings with the giant front wheel (long spokes for 'some' suspension on hard roads) were prone to a 'face-plant' crash, and I'm told the Starley "safety bicycle" of 1885 was a very big hit (in spite of the really weak front "spoon" brake). (edit, take note that the entire frame flexes as added supension)
spinningmagnets wrote: The other option for designers who crave an RC-motor is to add hall-sensors and use a larger 6-FET Infineon controller,....!
Users browsing this forum: No registered users and 9 guests