Center of loom?
water hand NM
Possibly, while doing
extended strokes and braces with one hand at teh end or near the end of a blade and the other center on the loom.
Thats my hypothesis.
Jim
Yes
That is where I have cracked/broken a GP…at least somewhere in the loom area and while using an extended paddle with bad technique no doubt. Such as goofing around and trying a C-to-C from the chest sculling position.
Uhhh…
– Last Updated: Oct-17-08 7:58 PM EST –
One of my buddy's first attempts at a GP broke at the blade not too far from the loom. He got a little carried away with the minimalism. I suspect a GP will break where it's thinnest in the blade, not the loom. The fulcrum to your lever is at the water hand. The greatest stress will be toward the water from that fulcrum.
I think.
The area that I hear of the most
brakes is at the root of the blade, near the loom. If a greenland paddle is made the way that Greenlanders have made them, the loom is thickest at the middle and tapers down as it goes to the blade. This gives the loom a good amount of strength. We don’t use or depend on our paddles as much as the Greenlanders did, so most paddles are made with a symmetrical loom all the way across and they seem to be strong enough for our use.
Broke one at the water hand.
Laminated spruce. Really liked that paddle…
I’ve done some flex tests…
– Last Updated: Oct-18-08 9:28 AM EST –
...and the point of greatest flex is at around mid-blade. OTOH, I've seen more failures at or near the shoulder, but they've usually been due to either a defect in the wood or a poorly designed paddle. The few loom failures I've seen have all been due to wood defects (knots, pitch pockets) or really poor grain orientation (lots of run-out in the loom).
The classic design mistake is to make the blades too thin with a sudden increase in thickness at the shoulder. For durability, the blade thickness should taper gradually from the shoulder to the tip. I've been building them this way and beating on them for years and have never broken a paddle, nor has anyone broken a paddle I've made for them. I attribute this to a good basic design (it ain't rocket science) and to being very selective about the wood I use.
It’s the wood
Having built more then a few GP’s. My experience has been that they almost aways fail where there is a flaw in the wood.
I’ve made some really thin GP’s that have not failed and others that were realy robost that did. In every case it was the wood that failed not the design.
Its kind of like breaking a baseball bat. Turn the lable just a little off center and it fails. Unfortuatly finding the perfect piece of wood is very difficute. I just made two paddles over the last two days. Both had the grain properly oriented, but one had 30 lines per inch. and the other came out a 12 lines per inch. I’m willing to bet that the 12 fails before the 30. Nowadays I build my paddles according to what the wood will allow.
Michael
More good input. Thanks.
This chunk of WRC has a very open grain.I don’t think the blades will fail since I’ve glassed both sides.
The last 2 paddles I made , and the next one, have been from 2-1"x4" epoxied together. I use ‘select’ pine from HD. Clear, and I can usually find a tight grain. I think bonding the 2 boards makes a strong paddle and it will not warp.
I haven’t found any difference…
…in durability with tight vs open grain, as long as the orientation is good. I use only wood with clear, straight vertical grain. The easiest way to find suitable wood is to buy a 4x4 and re-saw it into two paddle blanks. 4x4s are cut from larger, older trees and are much more likely to have clear, straight grain than 2x4s. Also, you get less grain angle variation across the width of the blank. My “Greenland Paddles” album on Webshots has a photo of what good grain looks like. The top and bottom blanks were cut from 4x4s, though one is laminated.
Brian, I agree with your taper argument.
A consistant taper with allow the stresses to be applied uniformally accross the paddle, and most likely to the diamond shape or hump before the loom edge. This hump is just outboard of the hand placement and likely to be where the most leverage occurs. Any disruption of the taper on its way to this area might create a stress riser and area of failure. What do you guys think about material? I have used cypress for one of my paddles with a long and narrow shape. I think this wood is the best I have experience with and the shape also limits the chances of failure. ??? Bill
loom break
I’ve had one GP crack near the middle of the loom, didn’t break through. That was during rescue of a swamped river kayak in the surf. Don’t remember exactly what happened, but somewhere in hauling the swamped kayak over my lap, I rolled my body and kayak over to gain leverage. The paddle was across my lap, but out toward the side I was rolling towards like an outrigger. WRC, good grain, but a relatively skinny loom.
Broke one laminated paddle at the shoulder learning to do a reverse sweep roll. But that was a crappy engineering job, crappy wood.
Broke one pine paddle at the shoulder when I got windowshaded learning why I should not try to surf dumping beach break. Paddle was caught between sand and kayak when I rolled over it on my way to eating my “sand-sandwich”. Glad it wasn’t my arm. On closer inspection later, a pitch pocket was revealed running right through where it broke. Just a tiny mark on the blade face, but a “cavern” inside…
Have never broken a paddle on the blade, but I agree, about 2/3s down to the blade tip is where the greatest flex generally is, but it also depends on where the fulcrum is at the time…
I’ve broken a couple other early attempts at carving, but it was all junk wood/bad design.
I agree with Brian Nystrom:
- Get good solid wood.
- Carve a solid design.
And I’ll add:
- Carry a spare anyway : )
centre of loom … . . no
i snapped one half way down the blade doing a roll in a swimming pool.
i was doing an extended paddle roll with a couple of children hanging onto the bow and stern.
i was trying to demonstrate how the gp had lots of purchase on the water: and i did.
it flexed between the middle and tip of the blade and snapped just out from the cenntre of the blade.
i did the same to a euro paddle a year before.
f
the
– Last Updated: Oct-21-08 10:47 AM EST –
weakest part of the paddle when extended and used to enter the kayak from shore with one end touching the ground....whereever that point is, it will break.
one little OOPS...I didn't mean to put any weight on it and You will find out......it could be differant for all paddles.
most likely if it's paddling related (not car door or bracing off the bottom related)...it will be about 1/3 of the way down the blade from the shoulder.
Best Wishes
Roy
Based on the above,I will not glass
– Last Updated: Oct-21-08 9:58 AM EST –
the loom. My daughter-in-law shouldn't be too rough on the paddle.