Re: Bike tech idea for Jeff

On Tue, 21 Jan 2025 22:11:02 -0500, Frank Krygowski
<frkrygow@sbcglobal.net> wrote:

On 1/21/2025 2:44 PM, Jeff Liebermann wrote:

 
Thanks for the suggestion (which got me thinking about the problem
again).  It will probably be a few years before I need to build
something.  One very useful takeaway is the Dyneema rope:
<https://www.dyneema.com>
I was going to use wire rope but I like the idea of making less noise.

I'd never heard of that stuff. Its strength sounds amazing. I wonder
about its abrasion resistance, though.

It's also new to me.  It's called UHMWPE (Ultra-high-molecular-weight
polyethylene).  It's one of the  polyolefin plastics (thermoplastic
polyethylene).  It's been around since the 1970's.  I must have been
asleep not to have noticed:
<https://en.wikipedia.org/wiki/Ultra-high-molecular-weight_polyethylene>

Abrasion resistance doesn't seem to be a problem.  The manufactory
claims "4X longer rope abrasion and creep lifetime compared to HMPE".
<https://www.dyneema.com/sectors/offshore-energy/engineered-lifting-slings>

I remember us talking about the inclined track idea.  But there may be
less elaborate methods that can do the job. I recall seeing, in some
European city, double clotheslines strung between two buildings, running
over a pulley at each building. Residents could haul their clothes in or
out by pulling the rope along the pulleys.

If I decide to do it crudely, something like that was my favored plan.
Two trees with a pulley attached to each tree and a wire or rope loop
in between.  Maybe a spring to maintain tension.  What stopped me from
just building something and testing it was that there is no tree at
the lower end of the hill that I can attach a pulley.  The nearest
trees are either 15 ft up the hill or across the road.  I would need
to bury a large concrete block in either my parking space or in the
road.  I have an idea for a compound pulley derangement that might
minimize the tension on the lower anchor block.

I wonder if a similar inclined cable could haul wood upstairs, from a
container hanging from one strand.

Yes.  That's roughly my plan.  However, to prevent spilling the load
on its way up, the container (box) will need to be supported by two
slings to the cable.  At this time, I carry the wood up the stairs
using one or two CLC 390 canvas slings:
<https://www.amazon.com/Custom-Leathercraft-C390-Canvas-Carrier/dp/B0001ZI53S>
It works nicely.  However, for a cable lift, I would need to wrap the
load with a self tightening strap to prevent spilling the load.

The problem with one cable strand or a single loop is that it takes
two people to operate.  One to load firewood at the bottom of the
hill.  Another to unload the firewood at the top of the hill and throw
it into a pile.  That's possible, but I'm trying to avoid solutions
that require and extra person.

Pedal drive would be charming, but an
electric motor would be easier to implement. One benefit would be no
infrastructure except at the ends.

Extrapolating my loss of strength and deteriorating stamina, I suspect
that an electric motor will be best for the long term.

Thanks again for the suggestions.

--
Jeff Liebermann                 jeffl@cruzio.com
PO Box 272      http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann      AE6KS    831-336-2558