Ropetek Wraptor redesign

After I posted I thought for a minute I was supposed to reference Burrapeg, not Santiago, such was the contribution of Burrapeg in his threads which I followed closely. Kudos Burrapeg and I mean that sincerely. Brother from another mother sort of thing. My first unit looked like the rollgliss/dewalt combo. I scooped up a rollgliss from the same listing Burrapeg got from but I didn't do much with it. It was neat to study the sheaves on it.

A comment on safety. The sheaves on my first one were larger and would freewheel down in conjunction with hitch/wrench when you popped the clutch. Popping the clutch is not a safety concern. The wrench is above the hitch and the ascender is below it. The hitch is always the core.

I chose to squeeze the sheaves down to fit better under the bridge area of the saddle. That's when I found the overall drag just a little too much. Perhaps I should loosen the wrench. Popping the clutch is just slipping a small button. Going down for positioning changes under drive is just to avoid clutching and configuration changes. Click reverse squeeze trigger, get slack, grab hitch. Small position changes.

Batteries are pretty standard inside: 18650's series and paralleled as needed be it laptop drill or tesla. There's other out there but 18650's are the bread and butter. The hard part is protection and management circuitry - which is tied to liability. Heating or blowing up the drive control is the other issue. And wires/connectors integrity. Oops, frayed wire shorted - smoke, hot, melt was that rope plastic? Doh. Or electronic malfunction - "turn off you stupid ... thing ...!!!! crunch. The kill switch on a wraptor is a safety feature, not just a use feature. I've always got a few shivers thinking about my PSP being an ignitable tank of gas and a hot muffler and plastic rope. But, risks can be managed as has been shown (so far).

The drill based prototypes get to tap the manufacturers embedded safety features built into both the batteries and controllers. At least the newer LiIon batteries aren't as burnable as the original chemistry was. On an older drill instead of electronic torque limiting there's the good old bumpy mechanical slip clutches to prevent injury in case of some other control failure. This is in the under-hitch configuration which I guess is the big change from the original wraptor concept. Under hitch can be argued to be not-life-support just like the rope wrench which could alleviate a lot of concerns. Maybe this other class of ascenders/positioners is not true to the original wraptor moving overhead PSP/TIP concept i.e. you hang a DRT system off the bottom of a wraptor.

Best wishes to all.
 
Referencing Santiago was fine by me; it was originally his idea and his heads-up that the guy in TX was blowing them out pretty cheap. The current prices on eBay are rather higher but still a deal for a DIY'er. And thanks for the kind words.
 
I don't mind the derail and fwiw I may have a rolglis around somewhere if anyone is interested. I purchased it just to check it out.
I could use it if you want to resell it. My local arborist here on the island saw me climbing on mine and went bananas over it. He really wants me to make him one. I don't need the hard case and other stuff if you wanted to keep that.
 
I could use it if you want to resell it. My local arborist here on the island saw me climbing on mine and went bananas over it. He really wants me to make him one. I don't need the hard case and other stuff if you wanted to keep that.

What's his name? A fella that works with me, and saw your demo at the Everett TCC last summer also wants one. And I gotta get my arse up there and work with ya on mine!
 
Ah, and electric definitly is the future and for a good part the present as well ;)
Beeing compatible with a big brand would at least give me as European a chance to run it. Some really good batteries (and tools) come from Metabo, and they became part of a "cordless alliance" here in EU:

And then there is Bosch...
 
I remember once at the Competition at Freedom park in Charlotte, I was talking with Paul, and someone approached Paul saying the Wraptor was too expensive. It turns out his very expensive electric ascender had ceased to function for whatever reason, and he wanted Paul to give him a discount. I see that the electric Actsafe is just under 13,000
 
Burrapeg,
My small second unit ended up at 2.980 sheave od by sheer chance/guess and the rollgliss is 2.888 od. My sheave teeth that were inspired by the winch and wraptor stuff are much bigger than the tiny rope zigzag path in the rollgliss sheave's teeth. Also, the rollgliss rope is brutally firm and really holds its round profile compared to a climb line. If I may ask, what was your final tooth-tip to tooth-tip width, at the od, after you split your sheave? On my 2nd unit i made it just big enough to start to fit tachyon in to achieve minimum sink of the rope into the sheave. I also upped my sheave angle to lessen rope sinkage. With your split sheave, do you know if the bigger ropes ride on your smallest id or does the rope not bottom? I'm almost contemplating a version 3. That's what winter is for - it's more fun milling in the cold, isn't it? For a notion of tedious, imagine milling up the sheaves without a rotary table.... and leaving no rope-unfriendly features behind.

Do you think there's any hope of tucking needle bearings into the rollgliss casting? I've yet to take mine apart but I recall mention of it having brass bushings. I figure those bushings are begging to wear out and cause havoc.
 
Hi Bart, no, none of my various ropes bottom out on the widened shiv (widened 1/8 inch). But I have two Rollgliss units converted now and what I have found is that it was completely unnecessary to widen the shiv. The original shiv works fine with every rope I have, from some 9mm stuff all the way up to my Tachyon Ash and Poison Ivy. No chance of roller or needle bearings in the casing I fear. Just not enough area there. And neither of my units have brass bushings. They are some sort of high tech stuff like teflon. I use Moly-D tapping oil as a lube to minimize the wear. This is some bad-ass lubricant. Molydenum Dysulfide molecules are like tiny hard ball bearings, spherical in shape and the heavy oil has a tremendous film strength. I have metal-casting capability (four furnaces of various sizes) so have given some thought to casting both the shivs as well as a new design of case which would incorporate roller or ball bearings. I don't envy you trying to mill a shiv! With or without rotary assist! Any photos of your project?
 
https://en.wikipedia.org/wiki/Shiv_(weapon)

I think you're thinking sheave. A sheave (/ʃiːv/) is a pulley with a grooved wheel for holding a belt, wire rope, or rope. The grooved wheel spins on an axle or bearing inside the frame of the block. This allows the wire or rope to move freely, minimizing friction and wear on the cable.

Maybe it's a gangsta ascender!
 

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