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Happy National Pfeffernusse Day! ⚪🇩🇪😋
Solo expedition build
- Thread starter Alan Gage
- Start date
Another weigh-in for the fat b*st*rd now that the inside is fiberglassed: 36.3 lbs.
Then I flipped it upside down and started sanding the exterior. Got most of it done. Will add some more epoxy filler in places before continuing. In the process it lost .5 lbs.
I'm surprised how much rigidity that knuckle adds to the hull. Handling all my other boats, even when fiberglassed inside and out, felt like a delicate proposition. This boat feels quite stiff and even if I push in and out on the gunwales there's quite a bit of resistance.
Alan
Then I flipped it upside down and started sanding the exterior. Got most of it done. Will add some more epoxy filler in places before continuing. In the process it lost .5 lbs.
I'm surprised how much rigidity that knuckle adds to the hull. Handling all my other boats, even when fiberglassed inside and out, felt like a delicate proposition. This boat feels quite stiff and even if I push in and out on the gunwales there's quite a bit of resistance.
Alan
Wow amazing progress! I think I'd trade some of that wt for security if I could. Pretty impressive doing all that testing....and now you're going with carbon on foam.
Are float chambers going to be the decks also? seems like a lot of people kep them separate. Not really sure why.
Are float chambers going to be the decks also? seems like a lot of people kep them separate. Not really sure why.
I'm really not sure. I've been using multiple partial bottles and haven't kept track. It definitely takes less to wet out and fill the weave of 4 oz. cloth as opposed to 6oz.
Maybe......
Still more testing to do. I'm a little worried about using regular construction foam. If it was just one of my regular boats I wouldn't worry so much but this one may see some more extreme usage. Hopefully it won't need maximum strength but it's possible. One of the test samples will be carbon over cedar.As you all can see I can get hung up on this sort of thing pretty easily. It was the same when I decided to build my own house. Life would have been much easier (and cheaper) if I could just build a 2x6 wall and stuff it full of fiberglass insulation. But as I started learning how to build a house I began to run into terms like air barrier, vapor barrier, rain screen, thermal bridging, etc and all of a sudden I couldn't be content with a "regular" wall, even though it's what everyone else uses, seemingly without having a problem. And now here I am messing around with all this testing when life would seemingly be much simpler if I just bolted on a set of fat ash gunwales. But it's an itch I've gotta scratch so I'll keep messing around. I can somewhat enjoy doing this testing as long as it's not interfering with the build but I'm about ready for gunwales so I better come up with something quick.
Alan
If I go with the float chambers I'm going to do the same thing. If I do a really good job on the inside Fiberglas maybe I'll convince myself to skip the chambers.
I know your pain on the home addition, I went through the same thing. Ended up with dense pack cellulose.
I know your pain on the home addition, I went through the same thing. Ended up with dense pack cellulose.
I always struggle to get it neat far up into the ends. On this one, when I rolled on the seal coat, I cut small pieces and laminated them into the stems. So when I laid out the full layer of glass later I only had to get within a foot or so of the stems. Made a lot easier and since the full layer overlaps the patched in stem pieces the seam is hardly noticeable.
My last boat was the first one I bothered to put decks on and I was surprised how much it hid the uglies hiding in the stems.
Me too. A couple insulation contractors in the area do damp blown cellulose but none of them do dry dense pack, which is what I needed for my 10" cavities, so I ended up doing it myself. Not fun....at all.
Alan
I'm really not sure. I've been using multiple partial bottles and haven't kept track. It definitely takes less to wet out and fill the weave of 4 oz. cloth as opposed to 6oz.
Maybe......
As you all can see I can get hung up on this sort of thing pretty easily. It was the same when I decided to build my own house. Life would have been much easier (and cheaper) if I could just build a 2x6 wall and stuff it full of fiberglass insulation. But as I started learning how to build a house I began to run into terms like air barrier, vapor barrier, rain screen, thermal bridging, etc and all of a sudden I couldn't be content with a "regular" wall, even though it's what everyone else uses, seemingly without having a problem. And now here I am messing around with all this testing when life would seemingly be much simpler if I just bolted on a set of fat ash gunwales. But it's an itch I've gotta scratch so I'll keep messing around. I can somewhat enjoy doing this testing as long as it's not interfering with the build but I'm about ready for gunwales so I better come up with something quick.
Alan
Alan, are you going to use the semi rigid pipe insulation found at most home improvement stores? Are there any specialty foam places that you could look at something a little different? Like an upholstery type foam? I wouldn't want the epoxy to melt the foam and leave you with a collapsed tube.
Momentum
I'll be trying rigid foam sold in sheets at home improvement stores. The pink and blue stuff, also known as XPS (Extruded Polyester Styrene). The commonly available variety looks to have a density of around 1.7-2 lbs/cu. ft. The high test foam, such as Divinycell, normally used in foam core composite layups, is more like 5lbs/cubic foot. But that's not an easy thing to source locally or cheap to have sheets of it shipped. Getting some would probably require a round trip to Minneapolis, about 6 hours of driving.
Polyisocyanurate foam (polyiso) is also readily available at most home improvement stores and is a little more dense at 2.2lbs./cu. ft. It's foil faced so I'd need to remove that but it should be easy enough to do when cutting the strips to size.
Epoxy should play well with either of the above.
By most accounts XPS isn't up to the task as a composite core. We'll see how it does.
Alan
Polyisocyanurate foam (polyiso) is also readily available at most home improvement stores and is a little more dense at 2.2lbs./cu. ft. It's foil faced so I'd need to remove that but it should be easy enough to do when cutting the strips to size.
Epoxy should play well with either of the above.
By most accounts XPS isn't up to the task as a composite core. We'll see how it does.
Alan
Alan,
You might be able to convince the manufacturer to send you some sample divinylcell sheet for your testing.
After all, you are an established boat builder. I have several large chunks of Dcell, but I leveraged my position as chief designer at a world renowned R & D company.
It's worth a try, they can't say no if you don't ask!
You might be able to convince the manufacturer to send you some sample divinylcell sheet for your testing.
After all, you are an established boat builder. I have several large chunks of Dcell, but I leveraged my position as chief designer at a world renowned R & D company.
It's worth a try, they can't say no if you don't ask!
Dear Chief Designer at a world renowned R&D company:
I'm a lowly canoe builder in NW Iowa with nowhere to locally source Divinycell. I'm trying to make my life as difficult as possible by testing as many different materials with as many different laminations as I can. To further confuse myself I'd like to see how Divinycell compares to lower cost and more readily available rigid foams. It's come to my attention that you have several large chunks of Divinycell in your possession and I was wondering if you would be willing to ship them to me free of charge. If I'm ever able to straighten out my thoughts and decide that Divinycell is the correct core material for me I can easily see myself needing a whole entire sheet!
Just kidding
Never thought to ask for samples, not a bad idea. Should have done that yesterday when I called to order the carbon, all I'd have needed was a couple pieces of scrap for now. The cost of buying a partial sheet doesn't really bother me, no doubt I'd find a use for it somewhere, but I don't know that I have the patience to wait around to have it shipped or to go pick it up. It's getting warm and the water is turning soft. I'm going to want out of the shop soon.
Happy news is that the carbon arrived already! Express Composites is based out of Minneapolis and regular shipping usually arrives next day. So tonight I'll laminate some XPS, Polyiso, and cedar. I'll let it setup and break them in a couple days. Raka says, if I remember correctly, the fast setting hardener achieves working strength in 24 hours@75 degrees. The shop will be set at 70 and after the smell and tack has gone out of them they'll spend some time in the oven.
Alan
I'm a lowly canoe builder in NW Iowa with nowhere to locally source Divinycell. I'm trying to make my life as difficult as possible by testing as many different materials with as many different laminations as I can. To further confuse myself I'd like to see how Divinycell compares to lower cost and more readily available rigid foams. It's come to my attention that you have several large chunks of Divinycell in your possession and I was wondering if you would be willing to ship them to me free of charge. If I'm ever able to straighten out my thoughts and decide that Divinycell is the correct core material for me I can easily see myself needing a whole entire sheet!
Just kidding
Never thought to ask for samples, not a bad idea. Should have done that yesterday when I called to order the carbon, all I'd have needed was a couple pieces of scrap for now. The cost of buying a partial sheet doesn't really bother me, no doubt I'd find a use for it somewhere, but I don't know that I have the patience to wait around to have it shipped or to go pick it up. It's getting warm and the water is turning soft. I'm going to want out of the shop soon.
Happy news is that the carbon arrived already! Express Composites is based out of Minneapolis and regular shipping usually arrives next day. So tonight I'll laminate some XPS, Polyiso, and cedar. I'll let it setup and break them in a couple days. Raka says, if I remember correctly, the fast setting hardener achieves working strength in 24 hours@75 degrees. The shop will be set at 70 and after the smell and tack has gone out of them they'll spend some time in the oven.
Alan
Foam
This PAST, and I HOPE PAST ! Winter, I finished my first Kevlar canoe. In it I used the Pink 1/4" foam that comes folded like an accordion, from Menards. (By the way I have a bunch if you want to experiment with it )
It will require further testing to evaluate !! I had originally thought of using 1/4" cedar strips in the bottom. Fearing that it would be just as heavy as a stripper, I opted for the foam.
The epoxy bonds to it fine, without melting it.
My fear is that the foam will just degrade in time.
It's laminated on the water side with one 6oz S-glass, and a layer of 9oz Kevlar. Then a layer of S-glass to cover. This is just to the waterline.
Seems stiff enough for now. But as I said, time will tell !
Jim
Like the discussion on differing composites ! !
This PAST, and I HOPE PAST ! Winter, I finished my first Kevlar canoe. In it I used the Pink 1/4" foam that comes folded like an accordion, from Menards. (By the way I have a bunch if you want to experiment with it )
It will require further testing to evaluate !! I had originally thought of using 1/4" cedar strips in the bottom. Fearing that it would be just as heavy as a stripper, I opted for the foam.
The epoxy bonds to it fine, without melting it.
My fear is that the foam will just degrade in time.
It's laminated on the water side with one 6oz S-glass, and a layer of 9oz Kevlar. Then a layer of S-glass to cover. This is just to the waterline.
Seems stiff enough for now. But as I said, time will tell !
Jim
Like the discussion on differing composites ! !
I've heard you mention building a kevlar hull and am curious to know how you did it. What did you use as a form/mold? I've heard kevlar tends to float in resin and that it can be difficult to get it to stick tightly to the substrate when it's wetted out. Did you have any problems with this?
Glad to hear the XPS insulation seems to have worked out so far. I wouldn't worry too much about the foam rotting away. It's rated for underground use under concrete slabs. Good thing about XPS is that it does not like to absorb water. Bad thing about XPS is that once it does absorb water it doesn't release it very easily. But that shouldn't be an issue in a canoe. Even in the case of a puncture at the beginning of a trip the foam shouldn't absorb enough moisture for it to be a problem.
My carbon showed up yesterday so last night I laminated some foam and cedar. I pulled the peel ply from one of the pieces of foam this morning and couldn't believe how stiff it was compared to fiberglass.
Alan
Glad to hear the XPS insulation seems to have worked out so far. I wouldn't worry too much about the foam rotting away. It's rated for underground use under concrete slabs. Good thing about XPS is that it does not like to absorb water. Bad thing about XPS is that once it does absorb water it doesn't release it very easily. But that shouldn't be an issue in a canoe. Even in the case of a puncture at the beginning of a trip the foam shouldn't absorb enough moisture for it to be a problem.
My carbon showed up yesterday so last night I laminated some foam and cedar. I pulled the peel ply from one of the pieces of foam this morning and couldn't believe how stiff it was compared to fiberglass.
Alan
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Hi Alan
I used a cedar stripper that I had glassed just the outside, for the male mold. I covered it with heat shrink film, that they use for windows. This served very well as the release agent between the hull and 9oz stitched Kevlar.
At The time I was using System Three's " Clear Coat" It wet out the kevlar OK, it seemed to take a lot more resin, if my memory serves me.
The biggest problem I experienced was the heat shrink film pulling away from the tumblehome. I'll remedy that with double sided tape this time.
Also the stitching in the Kevlar, left a pattern, unlike woven cloth.
Looking forward to some more test results !!
Jim
I used a cedar stripper that I had glassed just the outside, for the male mold. I covered it with heat shrink film, that they use for windows. This served very well as the release agent between the hull and 9oz stitched Kevlar.
At The time I was using System Three's " Clear Coat" It wet out the kevlar OK, it seemed to take a lot more resin, if my memory serves me.
The biggest problem I experienced was the heat shrink film pulling away from the tumblehome. I'll remedy that with double sided tape this time.
Also the stitching in the Kevlar, left a pattern, unlike woven cloth.
Looking forward to some more test results !!
Jim
Final round (I hope) of testing is in!
The size of the strips, just shy of 5/8x3/4", was the same as the last test and so was the span (9"), so direct comparisons can be made.
I laminated with 5.7oz carbon tape and topped it with 8oz. fiberglass tape. Some pieces got one layer of carbon and some got two layers of carbon. This test was considerably more expensive than the previous ones so I only tested one sample of each. I used Raka's fast setting epoxy in a 72 degree shop and I turned the heat down to 67 when I left for the night. The roller I'd used to apply it was already stiff by that time. At noon the next day I put them in the oven at 170 degrees for 2 hours and that's where they stayed, during the cool down, until 8:00 this evening. If they weren't at full strength they should have been pretty darn close.
I appeared to have had some lamination problems on the foam, a couple of them didn't stick real good. When the pieces were left to setup they were sandwiched between two sheets of 3/4 plywood with peelply and then weights placed on the top. Perhaps the epoxy softened a bit in the oven and allowed the cloth to pull away? It seemed to stay stuck tight to the cedar strips.
And now for the results. Again, just like the last test, these were broke on the 5/8" dimension. So 3/4" wide and 5/8" thick.
Poly Iso foam, single layer of carbon - 55 lbs
----------------------------------------------------------
XPS foam, two layers of carbon - 47 lbs
----------------------------------------------------------
Cedar, single layer of carbon - 181 lbs
----------------------------------------------------------
Cedar, double layer of carbon - 196 lbs
----------------------------------------------------------
Ok, first a quick word about the foam. I think this test really worked against it. The lamination was questionable and only 3 sides of the pieces were covered by the laminate. I think this works against foam but probably doesn't matter much for wood. The contact point on the press is a circle about 3/4" in diameter, so fairly small. The failure of the foam was simply that it started to crush at the contact point right away. A thicker cross section of foam firmly attached to the hull and completely encased in carbon would no doubt make for a much stronger structure rather than just the foam standing alone. Just how strong that would be I don't know. And most stresses on a gunwale probably aren't point loads. It's also possible the lightweight foam I was using was the main cause of the failure and something like divinycell may have came out better.
I was very surprised how stiff the pieces of foam were. I really couldn't bend them at all by hand. But if I pushed very hard with my finger tips I could feel the foam begin to give way beneath the carbon, so a bit soft.
Now how about that cedar/carbon combination? Even with just one layer of carbon it was considerably stronger than the best performance turned out by either oak or mahogany. The mahogany had averaged 147 lbs and the oak averaged 130 (with lots of variation).
But most impressive to me was the way the carbon covered cedar failed. It wasn't dramatic at all and I was unable to get a complete break. With the other woods once it started to let go it took very little force to keep bending it farther or else it cleanly broke in two suddenly. The carbon covered cedar (the double layer in particular), on the other hand, still withstood a lot of pressure even after it began to fail. With the single layer the carbon broke on the tension side and buckled the compression side but I had to push it quite a ways after it began to fail before I would have called it "broken".
With the double layered cedar the carbon would not break on the tension side but did eventually break on the compression side after bending it some more. Once the piece started to fail the pounds of force dropped from 196 down to about 175 (still well more than any of the other woods tested) and just seemed to stay there. After taking it out of the press I still can't break it the rest of the way by hand even though it's bent at quite an angle and the cedar is obviously fractured. Not only can't I break it I can't even bend it.
In case you couldn't tell I think I've made my decision, I'm going with carbon covered cedar at 1-1.25" thick. I'll probably single layer it towards the stems and double layer it in the middle where it should see the most stress. It will be topped with fiberglass tape for extra wearability. I'm going to try and vacuum bag it on the boat to be sure I get the best lamination possible but that could prove to be quite difficult. We'll see.
As for weight I think the gunwales should come in under 5 pounds and be as strong, or stronger, than traditional ash. Time and use will tell for sure.
Thanks to everyone for humoring me for the past week and thank you for all the great advice and information, it gave me plenty to think about. I meant to respond directly to more of the comments and suggestions but just didn't get around to it.
And now back to our regularly scheduled build, already in progress.......
Alan
The size of the strips, just shy of 5/8x3/4", was the same as the last test and so was the span (9"), so direct comparisons can be made.
I laminated with 5.7oz carbon tape and topped it with 8oz. fiberglass tape. Some pieces got one layer of carbon and some got two layers of carbon. This test was considerably more expensive than the previous ones so I only tested one sample of each. I used Raka's fast setting epoxy in a 72 degree shop and I turned the heat down to 67 when I left for the night. The roller I'd used to apply it was already stiff by that time. At noon the next day I put them in the oven at 170 degrees for 2 hours and that's where they stayed, during the cool down, until 8:00 this evening. If they weren't at full strength they should have been pretty darn close.
I appeared to have had some lamination problems on the foam, a couple of them didn't stick real good. When the pieces were left to setup they were sandwiched between two sheets of 3/4 plywood with peelply and then weights placed on the top. Perhaps the epoxy softened a bit in the oven and allowed the cloth to pull away? It seemed to stay stuck tight to the cedar strips.
And now for the results. Again, just like the last test, these were broke on the 5/8" dimension. So 3/4" wide and 5/8" thick.
Poly Iso foam, single layer of carbon - 55 lbs
----------------------------------------------------------
XPS foam, two layers of carbon - 47 lbs
----------------------------------------------------------
Cedar, single layer of carbon - 181 lbs
----------------------------------------------------------
Cedar, double layer of carbon - 196 lbs
----------------------------------------------------------
Ok, first a quick word about the foam. I think this test really worked against it. The lamination was questionable and only 3 sides of the pieces were covered by the laminate. I think this works against foam but probably doesn't matter much for wood. The contact point on the press is a circle about 3/4" in diameter, so fairly small. The failure of the foam was simply that it started to crush at the contact point right away. A thicker cross section of foam firmly attached to the hull and completely encased in carbon would no doubt make for a much stronger structure rather than just the foam standing alone. Just how strong that would be I don't know. And most stresses on a gunwale probably aren't point loads. It's also possible the lightweight foam I was using was the main cause of the failure and something like divinycell may have came out better.
I was very surprised how stiff the pieces of foam were. I really couldn't bend them at all by hand. But if I pushed very hard with my finger tips I could feel the foam begin to give way beneath the carbon, so a bit soft.
Now how about that cedar/carbon combination? Even with just one layer of carbon it was considerably stronger than the best performance turned out by either oak or mahogany. The mahogany had averaged 147 lbs and the oak averaged 130 (with lots of variation).
But most impressive to me was the way the carbon covered cedar failed. It wasn't dramatic at all and I was unable to get a complete break. With the other woods once it started to let go it took very little force to keep bending it farther or else it cleanly broke in two suddenly. The carbon covered cedar (the double layer in particular), on the other hand, still withstood a lot of pressure even after it began to fail. With the single layer the carbon broke on the tension side and buckled the compression side but I had to push it quite a ways after it began to fail before I would have called it "broken".
With the double layered cedar the carbon would not break on the tension side but did eventually break on the compression side after bending it some more. Once the piece started to fail the pounds of force dropped from 196 down to about 175 (still well more than any of the other woods tested) and just seemed to stay there. After taking it out of the press I still can't break it the rest of the way by hand even though it's bent at quite an angle and the cedar is obviously fractured. Not only can't I break it I can't even bend it.
In case you couldn't tell I think I've made my decision, I'm going with carbon covered cedar at 1-1.25" thick. I'll probably single layer it towards the stems and double layer it in the middle where it should see the most stress. It will be topped with fiberglass tape for extra wearability. I'm going to try and vacuum bag it on the boat to be sure I get the best lamination possible but that could prove to be quite difficult. We'll see.
As for weight I think the gunwales should come in under 5 pounds and be as strong, or stronger, than traditional ash. Time and use will tell for sure.
Thanks to everyone for humoring me for the past week and thank you for all the great advice and information, it gave me plenty to think about. I meant to respond directly to more of the comments and suggestions but just didn't get around to it.
And now back to our regularly scheduled build, already in progress.......
Alan
Alan, Once again, great stuff man!!
It never occurred to me to put carbon over a wood gunnel... doh!
Now you have me rethinking my carbon fiber over foam skin on frame guideboat plan. If I use some CF tubing over wooden ribs and stringers, hmmm.
But enough about my daydreams.
Now that you've settled on the gunnel construction, what will be the gunnel design? Will you stop short, or over run the stems?
And decks? No, you planned on some smallish bulkheads only, right? Teardrops?
And as if I haven't tossed enough questions out there...how are you with the weight? I know you wanted to build a tough boat, it should be bullet proof.
But, you're not actually going to shoot it, are you?
It never occurred to me to put carbon over a wood gunnel... doh!
Now you have me rethinking my carbon fiber over foam skin on frame guideboat plan. If I use some CF tubing over wooden ribs and stringers, hmmm.
But enough about my daydreams.
Now that you've settled on the gunnel construction, what will be the gunnel design? Will you stop short, or over run the stems?
And decks? No, you planned on some smallish bulkheads only, right? Teardrops?
And as if I haven't tossed enough questions out there...how are you with the weight? I know you wanted to build a tough boat, it should be bullet proof.
But, you're not actually going to shoot it, are you?
Great news: lots of pictures tonight!
Bad news: none of them are of the boat.
Here's that section of cedar with two layers of carbon that won my heart:
20150319_003 by Alan Gage, on Flickr
20150319_004 by Alan Gage, on Flickr
Tension side held:
20150319_005 by Alan Gage, on Flickr
Compression side broke:
20150319_006 by Alan Gage, on Flickr
Even as it is now, with that big kink it in, I can't bend it by hand either forwards or backwards. Probably could if I bent it over my knee or the edge of a work bench but with hands alone I can't do anything to it, and it's less than 5/8" thick.
Now I need to decide on a gunwale profile. One that will provide strength, be easy to pick up, and that will allow the carbon and fiberglass cloth to wrap around it easily. So tonight involved many more test pieces. Most of these are pretty rough yet and not exactly symmetrical.
20150319_007 by Alan Gage, on Flickr
20150319_008 by Alan Gage, on Flickr
The angled ones have a smooth transition to the hull and do a nice job of matching the angle of the knuckle on the inside. They also take away a lot of meat, which means less strength.
20150319_009 by Alan Gage, on Flickr
20150319_012 by Alan Gage, on Flickr
20150319_016 by Alan Gage, on Flickr
Simply rounded over would be stronger and still nice to pick up but not such a nice transition to the hull:
20150319_010 by Alan Gage, on Flickr
20150319_011 by Alan Gage, on Flickr
20150319_017 by Alan Gage, on Flickr
Somewhere in between? That sharp edge near the hull would be rounded over:
20150319_020 by Alan Gage, on Flickr
20150319_019 by Alan Gage, on Flickr
As for the boat itself I've been sanding away at the outside trying to get everything smooth. When I get tired of sanding I add some more epoxy for filler and then sand it back off again. Sometimes, when it seems like things are going too well, I sand too far into the cloth and then have to add a little patch that I get to blend in. Fun times. A solid colored hull really shows off the flaws and cat hair doesn't disappear on a white hull the way it does on natural wood either. I'm hoping I'll done with that tomorrow and I can spend the weekend playing with gunwales.
Alan
Bad news: none of them are of the boat.
Here's that section of cedar with two layers of carbon that won my heart:
20150319_003 by Alan Gage, on Flickr
20150319_004 by Alan Gage, on Flickr
Tension side held:
20150319_005 by Alan Gage, on Flickr
Compression side broke:
20150319_006 by Alan Gage, on Flickr
Even as it is now, with that big kink it in, I can't bend it by hand either forwards or backwards. Probably could if I bent it over my knee or the edge of a work bench but with hands alone I can't do anything to it, and it's less than 5/8" thick.
Now I need to decide on a gunwale profile. One that will provide strength, be easy to pick up, and that will allow the carbon and fiberglass cloth to wrap around it easily. So tonight involved many more test pieces. Most of these are pretty rough yet and not exactly symmetrical.
20150319_007 by Alan Gage, on Flickr
20150319_008 by Alan Gage, on Flickr
The angled ones have a smooth transition to the hull and do a nice job of matching the angle of the knuckle on the inside. They also take away a lot of meat, which means less strength.
20150319_009 by Alan Gage, on Flickr
20150319_012 by Alan Gage, on Flickr
20150319_016 by Alan Gage, on Flickr
Simply rounded over would be stronger and still nice to pick up but not such a nice transition to the hull:
20150319_010 by Alan Gage, on Flickr
20150319_011 by Alan Gage, on Flickr
20150319_017 by Alan Gage, on Flickr
Somewhere in between? That sharp edge near the hull would be rounded over:
20150319_020 by Alan Gage, on Flickr
20150319_019 by Alan Gage, on Flickr
As for the boat itself I've been sanding away at the outside trying to get everything smooth. When I get tired of sanding I add some more epoxy for filler and then sand it back off again. Sometimes, when it seems like things are going too well, I sand too far into the cloth and then have to add a little patch that I get to blend in. Fun times. A solid colored hull really shows off the flaws and cat hair doesn't disappear on a white hull the way it does on natural wood either. I'm hoping I'll done with that tomorrow and I can spend the weekend playing with gunwales.
Alan
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I love this...you're doing all the leg work for my build. I vote for one of the tapered versions probably second from the left in the picture that has five profiles. Good luck with the Carbon, I wouldn't have guessed it would make that much of an improvement, it will look sweet when it's done. Great effort and thanks for sharing I'm sure it will help many builders.
Well I'm happy to hear I might have given you an idea because I've taken plenty from you in the last year.
I'm not planning to run the gunnels all the way to the stems. I plan to have some largish, squarish, float tanks that will be part of the deck and I can't see a strength advantage to running the gunwales past the point where the tanks start. That should also make it easier to get a seal for the vacuum bag.
When I started the build I wasn't going to worry about weight. Figured I'd put thick wood gunnels on and it would come in around the low 50's. I guess that plan didn't last very long. By the time I finish sanding the outside I should be right around 35lbs. I'd be happy with 5lbs. for the gunnels and I hope by the time thwarts (probably carbon over foam), seat (carbon), and float tanks/decks (material undecided) are in that the boat will be 45lbs or under.
Well, I am thinking of adding some kevlar, but I probably won't be shooting it. I don't have enough carbon tape to double layer the gunnels so when I ordered more today I also had them send some kevlar tape along as well. Kevlar is supposed to be even stronger in tension than carbon so I'm wondering about the first layer being kevlar with carbon over the top. Looks like there will be one more test piece to laminate and break.
This build is going to be more work and money than I'd planned. I sure hope I like the boat once it hits the water....
Alan
