The Evolution of an Invention

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jomoco

jomoco

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You must know me, cuz I've got that album, straight out of the 80's!

"The last man to be here was never heard from again,

he won't be back this way till 2010."

jomoco
 
jomoco

jomoco

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How do you engineer an 8 speed gearbox for prototype 2 of my rope ascendor?

With two of these, allowing me to spin my drive axis 90 degrees with a miniscule loss of power delivery efficiency.

http://www.dynamicbicycles.com/chainless/

One for arms, with a coice of 8 gears, and one for legs with a choice of 8 gears also.

I have every intention of out performing the wraptor under my own power guys.

Now that I have a choice of 8 gears, that little lightbulb in my head is blinking again telling me that a spool on your back with 100 feet of rope on it would not weigh too much, and that there's really no need at all to have any rope whatsoever below me, except perhaps an anchor line for my TIP, independent from me, tied off at the base, and perhaps very handy for aerial rescue from the ground?

jomoco
 
Hddnis

Hddnis

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I'll be following this invention. It is similar to an idea I've been thinking about and sketching since last winter.

Do you have access to a welder? Mig or Tig?


Mr. HE:cool:
 
jomoco

jomoco

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I've heard/read somewhere that there is a continuous velocity, or shiftless bike out there, just costs several $k

As soon as I saw that Dynamic shaft drive using bevel gears, with a choice of 8 gears, it was obvious to me the ability to gear down 8 times will compensate for the growing OD of rope on the spool as you near the top of the tree, exactly like a true spider!

jomoco
 
John Paul Sanborn

John Paul Sanborn

Above average climber
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... will compensate for the growing OD of rope on the spool...
jomoco

Seems to me that that will be a pretty big spool with 100ft of rope. I was envisioning something that self tailed and spilled the rope out the backside of the spool.

There are plenty of boating winches with tailing jaws out there you could find any diameter you need.
 
jomoco

jomoco

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Seems to me that that will be a pretty big spool with 100ft of rope. I was envisioning something that self tailed and spilled the rope out the backside of the spool.

There are plenty of boating winches with tailing jaws out there you could find any diameter you need.

One model's development, by no means precludes developing another version, utilising the very real mechanical advantages of the original concept/prototype.

In my opinion both models should have tailing mechanisms at both the rope spool feed point, and exit point. Tautness and uniform rope lay on the spool are paramount to a dependable and safe operating prototype.

100 feet of true blue weighs what? 15-20 lbs?

Holy mackerel! Only 8.8 lbs! No problemo JPS!

jomoco
 
Last edited:
John Paul Sanborn

John Paul Sanborn

Above average climber
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100 feet of true blue weighs what? 15-20 lbs?

Holy mackerel! Only 8.8 lbs! No problemo JPS!

jomoco

I was thinking volumetric, not mass.

Maybe a static-line would work better on something like that with the stepping motion, and km-III is 7lbs/100ft

1/2", White/Blue, KM III Static, New England 1/2 inch (12.5mm) White (Blue) mbs 10,341 lbf. (46kN) 7 lbs (3.2kg) / 100 ft 1.10 FT
 
jomoco

jomoco

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Kinda serendipitously funny that you chose today to bump this old thread Tree MD, since the JB weld casted modification to my rope bike's drive capstan was poured last night, and tested at home today successfully!

After two miserable failed field tests in which the 3 wraps on the capstan walked sideways and derailed before I could get 10-15 feet up the rope, it was nothing but sheer stubborn refusal to admit failure that led to this current drive capstan finally tracking true under load.

http://www.youtube.com/watch?v=6iBuYtmw304

I tried a spiraled worm gear capstan design to physically walk that rope in the right direction, and failed. Then just figuring out how to cast the incline plane at the capstan's initial feed point without tearing the unit apart took another week of trial and error, but it does track true at home, tomorrow field test number 3 will tell the real story.

I suspect that an hourglass designed capstan will be the only way to get the unit to track true in both directions.

I can't believe I spent so much time and effort on this particular prototype since my new design spools the rope into a backpack, making whether the rope tracks true or not irrelevant to it's function. I guess it's against my nature to give up before the job's done!

If it works in the field tomorrow, I'll post my success in vid here. If not? It may be another week or two!

jomoco
 
ssurveyor

ssurveyor

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I look forward to your vid, keep plugging.

do you weight the tail end of the rope to get the capstan to keep a purchase on the rope?

Gordon
 
jomoco

jomoco

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I look forward to your vid, keep plugging.

do you weight the tail end of the rope to get the capstan to keep a purchase on the rope?

Gordon

Yes, with a 5 gallon bucket of water.

For some reason I'm convinced I can ascend faster on this selfpowered contraption than the new twostroke powered ascendors like the Wraptor, which to me is a funny name, since you don't actually take a full wrap on the unit's capstan, which isn't really a true capstan so much as a cam powered rope squeezing pulley.

I've got the gearing on this vertical rope climbing bike just about right for a relatively quick ascension, provided my 3 wraps on the capstan track true all the way up this time.

jomoco
 
jomoco

jomoco

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Well I certainly got a little taste of how al gore must feel, about 15 feet off the ground in a tangled embarrassing mess!

Must be my english blood and churchillian resolve to never surrender!

jomoco
 
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