WTB: Hemlock Peregrine

[Glenn MacGrady]

The most common bi-weave used in Canoes and Kayaks is a 50/50 blend, with arimid running longitudinally and carbon fill inserted at 90 degrees. As per Sweet Composites, it is ~8 mills thick and weighs 5.6 oz per square yard and costs $29/yd in 50" fabric by the roll. Carbon is 58% of it's weight. By comparison, the standard arimid fabric used in paddlecraft is 5 oz sq yd and 10 mills thick, costing $16/yd in 50"goods by roll. The usual carbon is 5.7 oz sq yd and 9 mills thick, costing $28/yd in 50" goods by roll lots. Both are 0/90 degree taffeta weaves, but I've always preferred the four harness crowsfoot weave because it lays in better and has a slightly lower "kink", which improves strength a little.

So if I'm reading this correctly, a square yard of aramid (Kevlar) would be lighter than a square yard of carbon at the same thickness. Is that right? For some reason I thought carbon was lighter. Maybe because every lightweight thing from bikes to car parts seem to be made of carbon.

Gavia, congrats on your purchase.

 

[charlie wilson]

Relative Densities of lamination fabrics, fresh water =1, Fiberglass 2.5, carbon 1.8, aramid 1.4, UHDPE 1, Innegra .8, all rounded to first decimal pt. Carbon and glass are more compression resistant, all others have higher tensile strength. Many items can be made lighter with carbon because it is so stiff, or resistant to compression and flex, but it is prone to traumatic failure.

 

[Guest]

Dave's boats would make that seem counter intuitive. The heavier boats are made with Kevlar, and are stiffer and the lighter boats are made with some content of carbon and are ever so slightly more flexible.

It then would come down to the thickness of the layering and the attributes of the different glass fibers on the outer layer which give these attributes.

I believe the goal is to achieve similar strength and stiffness characteristics between the different layups but reduce weight in the premium versions.

 

[yellowcanoe]

Have you considered how the resin is applied? Weight of resin and the method it is applied is not inconsequential. Are you a materials expert? I am not but am learning from Charlie who has worked with materials..

A more complete understanding is needed by some.

 

[Guest]

Have you considered how the resin is applied? Weight of resin and the method it is applied is not inconsequential. Are you a materials expert? I am not but am learning from Charlie who has worked with materials..

A more complete understanding is needed by some.

For the boats I was talking about the method is the same AFAIK. In fact I'm sure none of us know more about Hemlocks process than the guy who does it. So you might consider asking Dave instead of Charlie if you want to know for sure.

If you truly want to compare manufacturer A to B, then actually test it instead of analyzing how it is done. If you want to talk numbers, then include quantitative tests but I've never seen or heard of canoe validation. Seems to me all that backs up the expert is anecdotal evidence and material data which I can provide that myself.

I understand strength of materials, solid mechanics and know how to apply material properties to solving such problems but I find it much easier to just poke the boat and make my own judgement.

I should also add that I work in an industry that has more experts than I can count stars in the sky. If everything was so simply understood I should wonder why we spend so much time and money on validation?

 

[Guest]

Gavia, congrats on your purchase.

Thanks!

 

[yellowcanoe]

I don't fancy sitting except to stretch a leg out from time to time. I tell my canoeing students that most capsizes happen at the dock and one time one of them was so kind as to demonstrate.

One instructor demonstrated very well the effect of looking backwards over her shoulder and kind of hunching over. Now that's embarrassing!
What layup did you get and what gunwale material. I remain kind of locked to wooden gunwales. That way the yoke doesn't slide.

 

[Guest]

What layup did you get and what gunwale material. I remain kind of locked to wooden gunwales. That way the yoke doesn't slide.

He mentioned earlier it was the Kevlar hybrid... the standard. All Dave's rails are wood. Standard is ash. You can get spruce but I don't think he'd advise you putting them on a the heavier layup.

BTW the red looks real nice. Probably my favorite of his color choices (the orange is pretty cool too... it is General Lee orange... all it needs is a confederate flag decal).

Both mine are white. My least favorite color but it doesn't show the scratches as much.

 

[Glenn MacGrady]

Dave's boats would make that seem counter intuitive. The heavier boats are made with Kevlar, and are stiffer and the lighter boats are made with some content of carbon and are ever so slightly more flexible.

It then would come down to the thickness of the layering and the attributes of the different glass fibers on the outer layer which give these attributes.

Yes, this is now one of the greatest mysteries in canoe history: How does Dave Curtis reduce Peregrine weight by three pounds using a (heavier) Kevlar-carbon hybrid fabric on the interior rather than (lighter) all Kevlar fabric?

Maybe he uses less S glass on the outside in his "premium" layup. Maybe the different fabrics take up different amounts of resin even when resin is equivalently minimized. Maybe the Kevlar-carbon fabric he uses isn't really heavier than his all-Kevlar fabric because the weave tightness and densities are different. I can see on the Jamestown site that all these fabrics come in different weaves, which must affect weight.

Googling reveals that the Kevlar-carbon hybrid fabric appears to be very popular for a variety of uses including boat hulls and airplane fuselages. Interestingly, sites that sell this stuff often tout that it combines "the best" (rather than "the worst") features of Kevlar and carbon. Well, this is the old glass half full or empty conundrum.

Probably not many people have built more kayak hulls than Nick Schade. Here he is applying Kevlar-carbon fabric to the interior of a stripper hull. He also uses reinforcements of pure carbon and fiberglass in different areas. He says fiberglass wets out more quickly and uses less epoxy.

Who can solve the Peregrine mystery?

 

[yellowcanoe]

Well I am not about to run my Peregrine through a meat slicer for cross sections! Dave can solve it Proprietary knowledge. Maybe one of you will become his scion.

 

[Guest]

My 27# premium layup/spruce rail Kestrel is very stiff. Especially considering it's low freeboard. Maybe the stronger biweave requires fewer layers and so,less heavy resin? Anyway,it's a great,light layup and it works.
Turtle

 

[Guest]

It is a bit sad that Dave doesn't have a scion to take over his business. I think once he's had enough, there will be no new Hemlocks.

We could say that Bill Swift is Dave's scion in a way. He did work for Dave when he was in Rochester. Swift has taken a jump in technology though. Sometimes good, sometimes bad... but either way it is what it is. I rather like the hometown, cottage industry canoe. But those industries can't supply rental fleets for Algonquin or have the numbers in the field for feedback as a larger builder can. So in theory they should be able to go beyond and develop better products. But you don't get the personal feel you do with a small boat builder. You don't get the sense you bought something from a craftsman more than a factory. Those days are quickly fading, and I miss the craftsman.

The whole thing is a bit non-nonsensical sometimes. Hundreds or perhaps thousands of years old concept utilizing aerospace material technology. A hollowed out log will work, but leaves some things to be desired. I try to remember this. I also try to remember that I just do this for fun and while it might be fun think about new canoes and better processes, it doesn't take much to make one that will work. Same can be said for paddling. There are all sorts of spin moves and things that you can do in the canoe, but I think the most important thing is that you can go straight, and turn... and once I learned how to do that in a solo canoe, I was happy. Simplicity is bliss

 

[Bob B.]

l'oiseau,

Well said! I enjoyed reading your post and could not agree more. Technology can make things lighter, that is not all bad and when my knees have had enough or my shoulders refuse to work like they should I reckon I will praise it.

" You don't get the sense you bought something from a craftsman more than a factory. Those days are quickly fading, and I miss the craftsman."

"There are all sorts of spin moves and things that you can do in the canoe, but I think the most important thing is that you can go straight, and turn... and once I learned how to do that in a solo canoe, I was happy. Simplicity is bliss "

Well said indeed.

Bob.

 

[memaquay]

Simplicity is a relative concept. As long as simplicity gets you to where you want to go, it's all good. After my first white water course, my instructors were encouraging me to take more. I was ambivalent, said I didn't mind portaging. They came back and said that I was decreasing my opportunities to continue my wilderness explorations by not enhancing my skill levels. At the time, I think I mentally dismissed their arguments, but in the long run, their arguments have won out. The knowledge I gained from them enabled me to assess risk at a much higher level, and also enabled me to run many rapids that I had previously ported. I'm no whitewater specialist, but I'm a lot better than I was.

There are similar traits associated with canoes. After one has paddled enough of them for extended periods of time, one begins to notice differences in performance. Things are no longer simple. The old grumman canoe with a beat up aluminium paddle that used to serve all my needs is now something I don't like using. I especially don't want to ever carry it again. I have left it behind.

My idea of simplicity now is to sit in my canoe at dusk, as a full moon is coming up, several dozen miles down the Kapikotongwa river, fishing for walleye in a pool where no other person has been to for years. In order to get there, I had to learn more than simply going straight and turning. But the learning was a joy and exhilaration, and it never stops….I don't want to shut it off…an old dog can always learn new tricks.

 

[yellowcanoe]

Part of the joy of canoeing is that it can be simple. But it doesn't have to be..Starting way back with that old Grumman that got out once a year.. I was happy. Somewhere I wanted more and started messing around in my own boat. Canoeing went from once in a while trips to an everyday event after work (water permitting) with six hours in the boat whenever I could. Somewhere it became not a method of transport but a fun way to stretch and exercise and experiment.

I am still seeking all the ways the boat will turn or not turn and how can I maximize progress for minimal effort when I need to make speed in all condtions. The process of continually learning is exhilrating. The changing boat behavior under different loads and trim makes me wonder "Why?".

Similarly learning about various designs and why things were done or not done to me is most interesting. Some of the most educational time I have spent in canoe discussions has been with a block of wood. Charlie plugs it with an arrow to demo paddle forces. Tom MacK turns it into a boat to demonstrate hydrodynamic forces. And David Yost designs on it.

If only high school physics classes had involved canoes I might have liked physics much better.

And now hogging, oil canning, flat spots, sticky stems and lamination schedules are a lot more important to me than they used to be.

 

[Guest]

I have no idea why it feels slow, but it really does to me too. Oddly enough a kestrel doesn't feel that way despite being nearly the same boat just scaled down.

I'm pretty sure it's because the Peregrine just glides so good. It really doesn't take a lot of effort to keep it moving. Paddling near shore out of the wind I really noticed how long I could glide on a single kick.

In good conditions you can meander along in that boat with seemingly no effort. If you put the screws to it and bent shaft it, it will really cook too.

 

[yellowcanoe]

I have no idea why it feels slow, but it really does to me too. Oddly enough a kestrel doesn't feel that way despite being nearly the same boat just scaled down.

I'm pretty sure it's because the Peregrine just glides so good. It really doesn't take a lot of effort to keep it moving. Paddling near shore out of the wind I really noticed how long I could glide on a single kick.

In good conditions you can meander along in that boat with seemingly no effort. If you put the screws to it and bent shaft it, it will really cook too.

Skin friction . The Kestrel has less. That theoretical hull speed from the Peregrines increased length requires horsepower. Most of us aren't going to dedicate that hp over the long haul.

 

[Guest]

Skin friction . The Kestrel has less. That theoretical hull speed from the Peregrines increased length requires horsepower. Most of us aren't going to dedicate that hp over the long haul.

Agreed, but with a fatass like me in there the Kestrel is adding a lot more skin being lower in the water.

I think my point was that I don't think the Kestrel really is faster with a 200 lb person - it just feels faster.

I can't figure out how to double quote on this new fangled forum... but Gavia, 3 mph on an out and back river seems pretty good to me as well. I usually don't keep much track of speed but my last stream trip we averaged 2.5 mph in the Eagle including 3 beaver dams, a stop to filter water and some other misc. dawdling.

I may have said this already but side by side with the Eagle I'm a bit slower in the Peregrine with my straight stick and a bit faster with my bent shaft.

P.S. This text editor sucks. My cursor keeps jumping around me when I try to fix errors.

 

[yellowcanoe]

Um.. I'm not having problems with the edit function.. happy at last. I used to have issues. Buoyancy is a factor.. I would love to see the day when we can have a virtual canoeprint from the side and bottom with various loads.. and put it into motion using various paddler effort. So much is still anectdotal.. I suppose we have to factor in the development of such program would be hundreds times the cost of a canoe or a boatload of canoes...

 

[yellowcanoe]

Somewhere there has to be a desktop app that would do this. I'll ask my brother this weekend; he's a CAD designer.

In spite of my previous opines.. where is the like button?? YAY!