Ed Huntress wrote in
:
On Tue, 5 May 2015 02:18:19 +0000 (UTC), John Doe
wrote:
Ed Huntress wrote:
John Doe wrote:
Ed Huntress wrote:
Ed Huntress wrote:
John Doe wrote:
Assuming the drill needs to be held against the bicycle's bottom
bracket anyway, a non-locking connection turns out to be easy.
Lowe's sells 1/2 inch 20 TPI nuts in their specialty drawers (2
for $1.67). That nut fits on the DeWalt drill spindle. The
bicycle bottom bracket tapered spindle is about 1/2 inch square.
So a 1/2 inch drive socket that fits the drill spindle nut neatly
completes the connection.
I might carefully grind a little bit off of the bottom bracket
square tapered spindle and/or maybe the socket drive area so that
the 1/2 inch drive socket slides on a bit further, if I can
confidently do that. Don't want to make it off-center though.
Aha. It sounds like you're trying to lap-in the bearing cones on
the bottom bracket, right?
That should be "cones and cups." I have done this with bicycle
wheel bearings, but that was in my engine lathe.
https://farm8.staticflickr.com/7665/...ec9d50e7_z.jpg
A 1/2 inch drive socket pushes onto that but only about 3/16 of an
inch. Would be useful to shave the four sides of that spindle and/or
the inner square drive area of the socket, so that the socket will
slide onto the spindle further, but only if it can be done without
misalignment. A tiny bit of wobble would be okay, but only tiny.
Just what is it you're trying to accomplish?
I wanted to get the drill 1/2 inch closer to the bicycle, but since I
just realized how to secure the socket to the spindle, I will probably
forget about that optimization.
Maybe I missed it. That bearing looks sealed, so lapping it probably
is not what you're doing.
My bottom bracket is not like the picture. That picture is just to
show what the square tapered spindle looks like. There are different
bottom bracket designs, but apparently most use a square tapered
spindle like that.
The connection between the cordless drill and the bicycle's bottom
bracket spindle is even better than I thought. As described above, all
it requires is two parts, a nut and a socket. The nut goes on the
drill spindle (exposed after the chuck is removed). The 1/2 inch drive
socket goes on the bicycle's square tapered bottom bracket spindle.
And the working side of the socket goes over the newly acquired drill
spindle bolt.
And, as I just did, if about 1/4 inch of the socket (drive side) is
removed with a rotary tool, the bicycle spindle sticks into the drive
side of the socket far enough so that, inserted into the socket from
the other side, the small spindle nut (or bolt, depending on your type
of bottom bracket spindle) holds the socket securely on the spindle.
So the only loose part is where the working outer side of the socket
slips onto the large nut that's on the drill spindle.
Here are the parts in the order they fit together...
https://farm9.staticflickr.com/8822/...02750a4f_z.jpg
My electric bike will be extremely efficient like the following
YouTube example, but much better mechanically.
https://www.youtube.com/watch?v=MtmSXgjXXB8
That's pretty wild. I never would have guessed that would work --
spindle rpm is so low that I wouldn't have guessed that you have
enough torque, and the storage capacilty of the drill motor battery
would also seem to be low.
I suspect he's using a 36 V drill. He should be using the drill's
slipping clutch to help prevent motor wear and to prevent bicycle
damage, but doesn't look like it.
Cordless drills are designed for powering ultralight vehicles. They are
made to withstand harsh environments, they are light as possible,
include a slipping clutch, at least two speeds, compact and rugged, with
the best battery technology.
Unlike the YouTube video example... Mine will have a small 14 tooth
front sprocket and a large 42 tooth rear axle sprocket. That should put
it easily within the drill's low-speed setting for providing more than
enough torque. The high-speed setting may or may not work unless/until
it's replaced with a more powerful drill.
DeWalt's current cordless drill battery is 5 amp hours. Still not much
compared to gas, but I have real-world experience with 2.6 amp hour
NiCad's, so 5 amp hour lithium-ion should be fun. Two batteries being a
total of 10 amp hours is significant for typical electric power,
especially being lithium-ion.
I tried gas, and it wasn't. So I will use ultraquiet and reliable, clean
and compact electric power. And suffer shorter trips, or take lots of
spare batteries.
There is another ultra-simple way to attach an electric motor to a
bicycle, that allows pedaling at the same time. But it's not as sleek
looking. I will try that if this doesn't work out.