Research in Central Africa

Hi,

I do research in some very tall tree from the oldest forest of Central Africa, looking for some unknown species of tarantula.

To do so, I would like to have some kind of crossbow to shoot my sand bag far enough, it has to reach 150 feet + sometimes.

I was wondering where to get such cross bow as I do not like my Sling shot ... innacurate and not shooting far.
Are there any Arborist store that sell them ?
If so, which one ?
If not, how do I modify a normal cross bow for my work ?

thanks in advance,

Cédrik

The art of ballistic projectiles has been a topic of discussion on many arborist related websites.

At New Tribe they have a page showing a sling shot modification that a skilled shooter can send a weight attached with fishing line high into the canopy.


The Tall Tree climbers at Cornell U. have a YouTube video of their modified crossbow for really high targets.

http://www.youtube.com/user/CornellTreeClimbing

Sherrill Arborist Supply sells a giant Sling Shot on an 8 foot tall pruner pole. This shoots a lead shot bag with an array of different lines.


http://www.sherrilltree.com/Professional-Gear/BIGshot_2/Big-Shot-Standard-Kit

I make latex tube weighted on one end that launches its entire assembly into the canopy. It is strong enough to pull a throwline up and over any limb under 125 feet and then directly hoist my rope.

In an interest to compare the pros/cons of each here are my thoughts.

First there are two methods of pilot line insertion: One is the use of fishing string that requires a large reel and holder to allow the lighting fast payout not to be tangled and then by its retrieval installed another pilot line. This is do the fact the fishing string is not strong enough to hoist a climbing rope. The pilot line comes is sizes from 1/8” braid yellow cord all the way down to 1.8mm super strong floss. The second method is to attach your pilot line to your projectile so it can hoist the climbing rope directly. This allows only one stage to rope installation and is less trouble. Fishing string is cheap per roll and as you abandon the evitable tangles you violate the “leave no trace” pursuit that we endeavor.

To determine which will be best you need to consider the difficulty in the string/line/weights ability to pass over your target; become isolated among the boughs; and most of all feed thru to allow both ends to reach the ground.
Trees with rough or large limbs require slick line or/or heavy weights. The heavier the line/weights the more kinetic energy is needed to reach your target.

The jungle climbers I know use the big sling shot to send a 10 ounce throwbag into the crown with the thin super strong pilot line. The redwood climbers I know use the fishing string method installed with either the cross bow or the jazzed up hand held sling shot.

I also suggest the use of a collapsible cube to store and feed your pilot line. It is so maddening to fire a perfect shot only to be interrupted by a line grabbed by a tangle on the ground.
http://www.sherrilltree.com/Professional-Gear/Storage_7/Deluxe-Cube-for-Bagline


Hopefully each will respond to your post here and if not the two other boards to poll are:

http://www.treeclimbercoalition.org/phpbb/

http://www.treebuzz.com/index.php

The best advice I can share is that you need to know which eye is dominate for sighting your shots; practice enough so each shot you take is completed with an effort best described as “unconscious competency”. Any skilled marksman using a hand held device will effortlessly move thru the firing motions without pause as the target comes into sight and is released in one fluid motion. Pausing at the end of your draw allows you to waver and strain which spoils your shot.

Sorry for the long reply but as you can read I enjoy sharing my thoughts about reducing the frustration of the most hair-pulling facet of rope installation- getting the stinking pilot line properly set over the target limb.

Thank's very much,

this reply is helping a lot.

Cheer's