Pageviews past week

The cold world of skimo & alpine climbing

The cold world of skimo & alpine climbing

Sunday, September 26, 2010

Nomic mods?

A number of climbers have asked about modifying the original Nomic to change the umbilical attachment point like the new generation. The following is from a post I made on a climbing forum last winter after the OR show in SLC.

One of the new features Petzl has incorporated into the newest Nomic and other tools coming out the fall of 2010 is a way to add an umbilical attachment leash without it being under your hand while climbing.

Basically what they did is drill a hole through the aluminum section the protrudes into the pommel and then mill some of the Delrin pommel away to fit sling material down both sides and out the pommel. What Petzl showed at the OR show was some pretty thin cord (2mm or something like it). Not enough for my liking, thanks. So I did the same with a thicker diameter cord that would take something more than body weight. I have been using 4mm cord that tests at 900#

Easy mod to do to the old Nomic with a hand drill and a file if need be. I used a hand drill and a mill. Much cleaner answer than what I have been using.

Original attachment

Cut Pommel

Additional 5mm hole drilled.

both sides are then counter sunk and a new cord added

New cord slotted in the pommel, "New" Nomic!

After looking at this more closely I find it hard to believe that the new Nomic pommels with the serrated "spike" won't retro fit the old tools.

While looking at the new tools (all prototypes) and taking them apart at the OR show my guess was the old Nomics will take both the new picks and the new Pommel. Although Petzl originally said no on both, my Nomic pick/hammer fit their newest Nomic (I actually fit it to their tool)...but like I said they were prototypes at the OR show. I'll have mine shortly and will up date this blog entry when that happens.

More on the use of 4 and 5mm cord.

From an earlier BD email exchange last winter when I asked about the issue of the small BD biner (worried about the sharp edged proto types that I was using. The new Production stuff has much better and rounded edges) on 4 and 5mm cord laced to Nomics with a BD Spinner umbilical.

Black Diamond said:
"Just tested this to 800lbs (single leg). No damage to the 4mm cord or our steel clip (production quality with more tumbling to the part); the bungee webbing breaks first. Then pull tested our steel biner clipped to 5mm cord, this went to 1600lbs before the cord broke."

I would also make sure to use a knot like a dbl Fisherman's in drop form instead of an Over Hand which is typical and much weaker (30% less or more?) in this application. And something like half of the original tensile strength of the rope! Easy bet the cord broke at the knot no matter what knot he was using. But worth hedging your bets here for several reasons. But 4mm seems a good compromise for size (getting it under the pommel or in your hand) and strength. Hanging on a tool is not a dynamic load. Fall far enough and require static cord and webbing to take the dynamic impact load and you'll blow through 5mm or the webbing easily.

Either way I think the newest leash attachment is a good improvement on the tools...and worth doing on the older ones if you are so inclined. It isn't much work and I don't see a down side.

For those that asked. New Nomic picks (if they are cut for the hammer) will fit the old Nomic heads with a spacer...a simple washer will work there for a spacer. If they are not cut for the hammer the pick will bolt right up as normal.

From the prototypes shown at OR this winter the Petzl hammer and adze will not work without cutting up your old head a tiny bit. They were prototypes but I suspect very close to what we will see as production.

The new Petzl in cut head is to further support the hammer and adze in use. I used a similar technique to support the CT Nomic hammer without cutting the aluminum tool head and got a lower profile and better balance as advantages.

More details and photos in the link below.


Steve Barratt said...

Dane, will your hammer fit the new Petzl tools. I understange that the way they've milled the new picks is a little different. Are you going to do two versions - for old and new picks?

Steve, manchester, UK

Dane said...

Hi Stephen,
Yes our current hammers and picks will fit all the newest tools. Our hammer pick inter-face is slightly different in contour than Petzl used. I will be offering our hammer profile (smaller than Petzl's) in both versions shortly. So you can either have us cut your old picks (or buy new ones from us) to use our hammer or just buy the newest Petzl picks already cut for a hammer and fit our lower profile hammer the same way you fit Petzl's offering.


Anonymous said...

HI Dane.

Thanks for this helpful trick.

Just a question, which knot did you make with the accessory cord? A 8?

And can I use a 4mm without do something (like use a drill..)?

I bought yesterday 2 comics and a BD Spinner Leash ;)

Thanks a lot for your answer.

Regards, Laurent (Switzerland)

Anonymous said...

Rub the cord with snow seal to keep it from getting soggy.