Unicender

[Tom Dunlap]

A couple of years ago I crossed paths with Morgan at TCI Expo in Long Beach. He had just made his first version of the Uni. When I got home to try out this new tool I fell in love with it. Finally, a way to ascend and descend on a single rope with the same tool. No switchovers needed. That version wore a bit and the rope slipped. Morgan designed a solution using some small pieces on the leading edge of the bars. This wasn't the best solution because the Uni couldn't be dialed in very well. It went from lock to drop too easily. No feathering was available.

http://www.thompsontreetools.com/

Now he has the bugs worked out. Adding the radiused lips to the bars has made the tool so smooth use. For the last few weeks I've been using the Uni exclusively. No DdRT work at all. The trees that I've been working in have tie in points from 80-100 feet.

My ascending system is sort of a Frog setup. The Uni is my upper ascender and is attached to my harness with an adjustable bridge. In the pic I have a small screwlink. This didn't work very well so I changed to a bowshackle.I think that the best setup would use a delta link to keep things fair. This setup has promise. This morning I got the idea to use my Positioner as an adjuster. In the next couple of days I'll have reconfigured.

My left foot stirrup attachs to the bridge and it comes off when I get to the TIP.

The Pantin goes on my right foot and stays there all of the time, including going to lunch...I like the jangle of spurs

My chest ascender attachs to the bridge shackles on my BF II by a short webbing runner on the left and a delta screwlink on the right. The two attachments allow the chest ascender to offset to the right just a little. This was an unforseen advantage. The rope tails out of the chest ascender and lines up nicely with the Pantin. When the chest ascender is centered the rope comes in at a bit of an angle. The upper part of the chest ascender is attached to a piece of nylon webbing which clips to a loop on the back of my harness. The chest ascender stays on while I climb, but not to lunch, since I occasionally have to ascend a bit while in the canopy.

By adjusting the bridge close I can make easy adjustments and position myself perfectly. When I get the adjustable bridge tweaked I'll be able to make the fine adjustments.

When descending I slide the bridge up, loop the rope over the top of the Uni and pull down. The action is very similar to using a Munter. The difference is that when the I let go of the rope I don't fall and the rope doesn't spiral and get hockled up.

Last Sat. at the GaTCC Gary aka Panteraba gave it a go. Since he hadn't used the Uni very much I gave a backup belay by holding the rope. Then I had him let go of the rope so that I could lower him to the ground. This worked very nicely.

 

[Tom Dunlap]

Another version using a Microcender

 

[Tom Dunlap]

Ascending

 

[Tom Dunlap]

Working

 

[Tom Dunlap]

Descending using my hand to release the Uni.

 

[Tom Dunlap]

Descending using the rope to release the Uni.

For a long time I've been tinkering with using SRT as an arborist working system. With the invention of the Unicender we are now able to begin. Morgan has some other devices in development that will push this idea further. In time, I firmly believe, we'll see more and more arbos working completely on SRT.

 

[NickfromWI]

Tom let me splice that thing!!!!

love
nick

 

[Blinky]

Looks like some pretty sharp bends on the rope... is that a strength loss issue?

 

[Blinky]

You know... Guy would probably fire me if I showed up with one of those.

 

[Tom Dunlap]

The rope doesn't make any sharp bends. Did you look at the Unicender webpage?

 

[Blinky]

Yep I did... it's the loops of rope above and below the device illustrated on the 'usage' page that I'm not up with. It was the picture of descending using the rope to control the device that first made me think that... but now I see what's happening with the wrap thrown over the actuator to control it.

I like it. Interesting that at the estimated $.45 per hour (dirty ropes with advanced mode on SRT), it's probably close to most manufactured split tails in cost.

The idea of working SRT is very cool... you could still put in a second crotch using the tail with DRT if needed too. I'm in no position to buy one right now but I'll be watching closely. SRT could speed up movement in the tree for me a good bit... minimize my blundering with a fouled rope too.

Of course, Guy will still give me grief about my gear no matter what.

 

[rich_h]

Let me state for the record that I am not the worlds biggest fan of mechanical devices for friction knot replacement for various reasons. That said, I absolutely will own one of these Unicenders. The action on it is so much nicer than any other mechanical device I have used that it is frightening. It descends beautifully and can be feathered for precision positioning, all of this on a single line!!!! Granted I did not get to work an entire tree with the piece and I am not entirely sure that I would use it for that purpose anyway, it will be an excellent addition to the tool box for single rope ascending and more than likely for working a spar with a single line.

 

[snakekeepr2]

When will they be available on ebay?

Keck fu master your numbers up

 

[Tom Dunlap]

Blinky,

Both of the eyes where a rope is terminated are radiused. They are both larger in diameter than carabiners so there isn't a concern about diameters.

 

[No_Bivy]

Ok so your are on the return trip from a long limb walk, how do you tend slack back in?

 

[OTGBOSTON]

good stuff Tom!

would you mind posting a pic of the attachment of the chest ascender to the bf2?

Thanks,

 

[Tom Dunlap]

NB,

Returning from a limb walk and tending slack is the [smallest] negative with the Uni. On DdRT it works so smooth!

On SRT I've found a couple of ways to tend slack.

By pushing the Uni bridge up I grab the bitter end of the rope for balance and push the Uni up with my other hand. At times I find that there is enough rope weight below that the Uni slides up almost as smoothly as in DdRT mode.

If a comparison chart is done with DdRT/SRT I think that this issue would be the only loosing point for the Uni. And...it isn't a complete capitulation. Tending slack with two hands isn't that hard or awkward.

OTG,

I'll see if I can get a decent pic of my current chest attachment. Yesterday I thought of a different attachment system that I'm going to configure.

 

[kevknep]

Nice looking device. The Unicender seems to solve the one main problem I always had when trying SRT, and that was trying to switch to descent if I decided not to go all the way to a tie in. I would practice low to the ground, so never had a chance to lanyard in to switch. Sometimes I had a lot of trouble removing ascenders and the like. This looks like you could hang from the unicender, tie a prusic on for a backup and then just remove the chest ascender and descend.

 

[moss]

Tom, do you always use a Yates Screamer for SRT or is it mainly because you're configuring for work climbing on the Uni?
-moss

 

[KentuckySawyer]

Tom,

I'm unfamiliar with a Yates "Screamer." What role does it play in your setup. Also, do you adjust the length of your Unicender setup (short piece of Blaze w/ micro adjuster) much? For what reasons? Ascending vs descending?

Looks like an interesting tool. Personally I like the aesthetic idea of rope on rope, but thats just a personal bias.