30. Product Safety Advisory 07/01/19

Moses Enterprises TOMAHAWKS
Wire Sling Strength Variations

If you have purchased Moses TOMAHAWK aid climbing pitons made in 2019, the wire slings may not have been swaged properly in order to achieve their highest strength (close to or equal to the tensile strength of the wire itself). More and more of us rely on TOMAHAWKS for both progress and protection so both placement security and sling strength are important.

From time to time we tensile test various products. For decades we have tested carabiners, cams, nuts, quick draws and all sorts of stuff - singly or as may be rigged on a climb. Not to get too techy, but our rig includes a hydraulic pull back ram cylinder and a Dillon 10,000 lb Dynometer. We affectionately call it "The Destroyer".

Recently we tested the strength of our Ultratape Sling when fitted to a Moses Tomahawk Piton. It’s been a popular option for both upper and lower holes for a variety of reasons. Hand placed Tomahawks can be so darn good that many of us consider them better lead protection than the smaller half of our micro nut rack. We had a pretty good hunch of the outcome ahead of time because we regularly add this Sling (with 4 bartacks) to various aid hooks - with minimum breaking strengths way North of 3,000 lbf. The set up was to apply slow-pull force to a Moses Tomahawk Piton via our Ultratape Sling (upper hole) and Moses’ burly 1/8" wire sling at the bottom. These were connected to a 7/16" diameter steel carabiner at one end and a 7/16" diameter hardened steel bolt at the other. Web or wire - the goal is always to produce a splice that is stronger then the looped material that bears on the carabiner or bolt. We expected the Tomahawk wire sling (same size as a #10 Stopper TM) would fetch a similar value of the #10's rating - 10kN (2250 lbf)... and if the Ultratape was cut or the weakest link, we wanted to know about it!

What concerned us were two very different results:
1) Some Tomahawk's wire slings failed at very low strengths - some less than 500 lbf and closer to the strength of a 1 or 2 Stopper TM (not the #10) and possibly exceeding the force of an aggressive “bounce test”. The rest similarly failed (ie wire pulled out of swage) in the 900 lbf range.

2) Secondary testing of the same Tomahawks (no wire sling) proved the Ultratape Sling was quite durable and strong - again over 3,000 lbf in the upper eye with minimal visible damage. This suggested we take a closer look.

A bit about swaged cables – so you know what you are clipping: Aluminum swages are commonly known to net 50% of rated cable strength in straight-line pull tests. Copper swages are capable of making a straight splice as strong as the cable itself and 1/8” galvanized cable tensile strength is advertised at 2,000 lbf. Swaged loop slings theoretically are twice as strong as straight line splices and typically we see loops fail at their support points (carabiner or bolt) - not the swage - so a good Copper swaged sling (as Moses uses on Tomahawks) should fetch over 2,000 lbf.
We also dug around and found a 2017 Tomahawk and tested it with a similar sub-optimum result (under 1,000 lbf), again with the wire pulling out of the swage.

Another 2016 or maybe 2017 Tomahawk checked in as should be expected with the wire sling breaking at 2010 lbf - which was encouraging. See photo below.

We then tested a 2017 #3 Moses. Alumahead (1/8" cable w/ Aluminum swage) over the more "friendly" carabiner and bolt which netted 2700+ lbs and remained unbroken! Although inconclusive, these limited test results suggest revisiting both the swaging process and quality control points for Tomahawk Slings. Do to these variations and inconsistencies, we have alerted Moses Enterprises, shared our test samples and results and recommendations for a remedy - which we hope will be forthcoming very soon. Short term, back up the wire sling with a loop of high-strength Bluewater Titan Cord tied with a Grapevine. This fetches 2,000 lbf minimum in our tests.

In advance of a published manufacturer's solution, we want to offer our Friends and Customers a couple of options. At minimum, Mountain Tools will accept unused Tomahawks for exchange. Once assured and proven that new production wire slings meet common industry strengths for their product category, we will replace your Tomahawks. This will take time. Keep in mind, Tomahawks are primarily an aid climbing progression piece and are not currently strength rated. That said, all gear placements should be suspect, evaluated carefully, backed up and tested before relying on them.

A quicker fix is for us to add an Ultratape Sling at the bottom hole of your Tomahawks (new or used). Ultratape's proven toughness and Minimum Breaking Strength should boost you confidence – certainly on aid and while making carefully calculated free moves. **If you have received your Tomahawks from us this year January thru June 2019 and decide to choose this remedy – for the slight cost of return postage - we will add a sling free-of-charge.** See our Resling Page for additional info.

Thanks for your continued patronage and trust in us.
Your Partners in Climb,
Larry and Jane
800 5.10-2-5.14 / +831 620-0911

* You can read about UIAA Standards, EU Norms and CE Certifications online - as they pertain to PPE (Personal Protective Equipment), pitons and other climbing equipment.

** For Resling Service send your recently purchased Tomahawks with a copy of your invoice via post to:
Mountain Tools / Tomahawks
POB 222295
Carmel, CA 93922

For more information see: http://mosesclimbing.us


Good to Go! Tooling has been replaced and testing has been upgraded. Green paint on wire sling indicates manufacture after Aug 20, 2019 with acceptable swage strength. Problem solved!