Okay, my plans are set, and I purchased materials. The admiral will be out-of-town for a week, so I can hopefully get some work done. I'm planning to leverage some wood pieces sanded to shape for my rudder upgrade. Here's the simple plan:
Step 1: Buy wood parts.
Step 2: Glue them onto existing rudder.
Step 3: Sand the wood down to shape.
Step 4: Finish the wood for durability.
My materials are two 1x12 wood boards (22" long) to attach to each side of the metal plate, and a 2x2 wood board, also 22" long, to create the front blunt edge, both select pine, and marine epoxy for glue. Still have to figure out the finishing, maybe cover with fiberglass.
The cross-section of the rudder will approximate the foil shape, but how should the bottom be? Should it just end flatly? If the rudder is like a wing, many airplane wings have little winglets. I am curious if adding a short horizontal stabilizer type winglet across the bottom of the rudder would help it be more efficient? It could also help keep the rudder in the down position too, maybe.
I'll post some pictures as the work begins.
If you are using the stock rudder as the template for your foil, why not let the aluminum plate act as the leading edge and sculpt the wood just up to that? The quarter inch plate will not break or deform if it hits something, so the wood should not be impacted at all. I may do the same thing with my old rudder someday. I have a manufactured foil on my 16 now, so the original is just sitting. You may also want to through bolt the wood in a couple places just in case the glue lets go. You can set the head and nut into the wood and epoxy over them. If you do it this way I would recommend that you glass the whole thing and finish it bright. I don't recommend this out of aesthetic sensibility, rather to make it so that if the wood starts to rot under the glass you will be able to spot it before it gets too bad. If you add a 2X2 to the front of your foil you will change the lead of your leading edge which might affect the way your boat handles. That may not be a bad thing. I have read that doing this can help with weather helm. I guess you would have to try it out and change the shape if it doesn't feel right.
This should be a fun little project. Sculpting wood is one of my favorite parts of boat building.
Al
Quote from: Duckie on December 11, 2015, 10:27:07 PM
If you are using the stock rudder as the template for your foil, why not let the aluminum plate act as the leading edge and sculpt the wood just up to that? ..... If you add a 2X2 to the front of your foil you will change the lead of your leading edge which might affect the way your boat handles. That may not be a bad thing. I have read that doing this can help with weather helm.
Al
Extending the leading edge forward about 1 1/2" is actually one of the two main critical design improvements in this modification. The second is the foil shape. The IDA/ruddercraft design, which has quite a bit of R&D put into it, moves the forward so that the leading edge is actually somewhat under the boat, as opposed to behind it.
You WANT the leading edge to move forward. This is what improves the weather helm. Not doing so will lead to a lot of trouble for much less than benefit than one would expect. Without a doubt, put that leading edge on there.
I would not use pine here though. Use 1088 marine plywood or solid hardwood with anti-rot qualities. A 4'x8' 4mm sheet will cost you about $35 and should be enough to do the entire rudder with some to spare. It's lightweight, easy to laminate/sand, resists warping in temp changes, and should last a long time provided it's sealed well. Sheath the wood in a layer or even two of 6oz fiberglass once shaped, then fill in the glass weave with more epoxy until smooth. I would add a little thickener to the second coat..not a lot, just a little, then let cure, sand and apply a third smoothing coat. Sand, prime, then paint. You'll need the thickener for the lamination process anyway.
You could also extend the rudder downward a few inches to offer more surface area to bite the water.
The devil is in the details when it comes to DIY rudders; there is a lot of info on this site to design it correctly if you search for it.
Nothing wrong with using foam too. If I were to build one, I would probably lay foam over the metal blade behind the leading edge, then cover the foam in thin marine ply. You want about 1 1/2" of chord so calculate the thickness of foam and/or wood you need considering the thickness of the rudder. Remember the fiberglass layer is going to add about 1/8" overall (1/16" on each side), so your raw materials should be about 1/1/4" thick at the chord before 'glassing.
It's going to want to float anyway, so might as well make it as light as possible and plan on a downhaul line, or one of the neat Com-pac rudder handles that are equipped on newer boats.
Just my opinion as a long time reader of this site.
tmw:
I did the exact project you are describing when I rebuilt my flat blade rudder into a wood foiled blade. It really transformed the feel of the boat. I have photos I can send you but the process is described in my thread "The Continuing Adventures of Koinonia"....somewhere....I'll try to find them. Meanwhile, see if this makes any sense:
http://s617.photobucket.com/user/Bob23_photo/library/Koinonia%20rudder%20project
Some of the photos may not be pertinent to your project but some will be. I'd be happy to discuss this with you on the phone, just message me your number.
Have fun!
Bob23
Okay, so I began the process of glueing the wood into place, currently held by clamps. I'm thinking to keep the wood strong, using a copper naphthenate treatment after sanding to shape. If things go to crap, I'll have to order and IDA rudder as a replacement.
Thanks for all your comments.
Tonight was glue for the leading edge piece of wood. Let's try some pictures.
Here was last night, putting the side parts on, and you can see the boards don't cover the entire existing metal rudder, but that's okay because at the trailing edge they would be sanded down to match the metal thickness anyway:
(https://lh3.googleusercontent.com/3ftci4TxHxlttMex-UtjPVGdMkHidkNm9efhw0jdFGYOpc8yA740thR21DmmTtgZcVmxPRBgur55Y9E_6Q-iTnTpfJcKfQMLzMZhiH5SJkMm4XnNFq7M35mBh2Vbpzxq6_NB68pu3zfoKW0ViHE6Fv1iUt-xf50y_hd2vvePiSSlR0uopAyp5q0sKOSF15azppC8bQUN87a5HbWjs5wBrIGmgBG4TCMsvVdDVYE7pH2ex1aVgZJ6cETwmXy47VYoea6TmSS61QYOCtS0oNIx1TFh5u6b3HOKJoN61JC9RXetpF6nl7EbsqzTkk4nz574CDpYcL6bpwheQTEsMF996BHxYq9pzx1kaQ3pXazsJEgBJQ7g_lzcG3glP9hINHQb01YckNys_t0M6RSFj7tDGMuUyIow32Obz2f1uhueF4_04N9mr2g839r5gq4HYZDHIQncIXO5fCm9Fcl7bUd9hnxReUudQsMOfNW7B7x6CKDZ9QDokjB3-n4EE3nwzUm3EwpwUL2rYCPj3O13VbCg8Vrjgv0shgaUeRpL21PYRU6THCS47DziNlzlDK703UgsXJCU=w382-h679-no)
Here is tonight, attaching the front leading edge. It's not quite as wide as the boards with the metal plate in between, but should make a smooth surface once they are fully sanded to shape:
(https://lh3.googleusercontent.com/qOFKgvfuIoHO64vdpdKZL95-aEQnZ4v67_v8h70Bbil-74dz2wm2O3XkmpP3YQ1bo3VPylRI1BmxSuwvwf4RCgr4LhhPOyjppCDCWQ6Nnv5_hX469gu45h8v90Yn7cG0S5WKHgtKVpghGux6OR3sW-cLD90_4fgddRSTRlfacEU8B8ZiTmxVV1b4QT2IEEe1zLsimLZRQ7Tq53gK_NG0AGO0dArOuno_0bpAeEC8Di4iVVRyRSAVvXxIas-0kxVuuRZ-rkbARdk_9EITlsEXDdEUsFvedQxfkDR7tpwRez-2ulyN2jw4zbBhxLSWHEH4FoSVQY499PUOjpcE3Z66iWyyiTqc9U0zDw_kztBc9TwIiaxHBNgMRilxV49ynDGWmf-QN_at-0Q9PEVT7mMnsR14LODs6m4a-K5xZmrO9al8zirgB_9F1_L1olEFj2OMi_1Jt1ue6gw-UUjBGkmVuDVrQ-bot0RtbhgkFaQH8DUbs5LCvRA2iacwtHpvBY91Tazu4thI2t9Sysc5tsWrQT9wT-vqBg4D2Fi_VIGPpc8cHZFOsPtyMj3FVI52d1j__Zip=w382-h679-no)
Happily, while purchasing more glue (using marine epoxy, because it says "Marine", wait, would anyone here be offended at jarhead jokes? I don't want to get banned already) at the Home Depot, I found the supply of fiberglass and resin, so I purchased that tonight, along with the coarse belts for shaping the rudder (hopefully tomorrow); and the copper stuff should arrive tomorrow also. My goal is to be nearly done before the admiral returns Friday, and kicks me out of the house.
These images aren't photobucket, but rather the image url from the google photos, and it works for me so I'm hopeful they show up for others. If the images don't show for you, let me know. Last night photobucket was giving me fits trying to upload pictures, kept getting 98% complete and quitting on me, so I'm optimistic this method might work.
Tim
I see them. I found a pic of the latest incantation of my rudder with hold down bracket. Notice it tilts quite far forward.
Bob23
(http://i617.photobucket.com/albums/tt260/Bob23_photo/Koinonia%20rudder%20project/20150503_123627_zpssuycchyd.jpg) (http://s617.photobucket.com/user/Bob23_photo/media/Koinonia%20rudder%20project/20150503_123627_zpssuycchyd.jpg.html)
I'm following this with great interest!...Why Pine wood? Pine is a soft wood, but easy to work with. Why not a hard wood like white oak? I bet you could get 20 years service out of oak? Good job and great pictures! Tim
What type of glue? White Elmers wood glue?
Bob, is the rudder supposed to sit that far forward? Also, how did you finish the top and bottom parts? I keep thinking that a small horizontal fin (like a wing keel) across the bottom could be fun, but also scared about that option. Anyone have guidance on the benefits of wing keels, and how that can apply to a rudder?
My reason for selecting pine was that I could readily find the size and shape needed from my local home depot, and it was pretty inexpensive. It's also easy to work with, and hopefully sinks better than foam. Foam would be much less expensive (have a bunch sitting around), but could lead to a floating rudder. Light and big enough, and it could help provide buoyancy to the boat ;)
The other reason I think pine is acceptable is that I plan to seal it. The copper naphthenate solution arrived this morning, and then encapsulate the whole think in fiberglass (hopefully helps with the softness too, maybe).
The glue I used was Loctite Marine epoxy. I don't think Elmers wood make a good connection with the metal plate, although it could make removal pretty simple.
The sad thing is I didn't get the sail the boat before the cold weather set in, so I really don't know how much of a difference this will make, so I guess that means anything can be a success.
TM:
Mine does because I trimmed some off the top of the blade to allow it to tilt like that. The stock blade does not.
A few notes on your project: Although you have not sailed your boat without it, the improvement will be obvious to anyone who has sailed a 16 with a stock blade. It will float! No doubt. If it's pine of foam, it will float. You will need a downhaul or better still, the Compac hold down bracket. I devised a rope downhaul and it worked ok but didn't hold the blade plumb. The bracket will. If the blade is allowed to float back even just a little, the weather helm will increase resulting in less fun and less speed.
Mine is foam around hardwood frames with 1/8" okueme plywood and fiberglass over all. The top and bottom are white oak which was from rift grain white oak flooring.
I'd advise you to forget about the wing on the rudder. The keel and rudder, while working together really perform different functions. Your foiled blade without the wing will perform just fine.
Bob23
I wanted to be lazy and watch a movie, but took the time to work on the rudder while the admiral was away. My grandfather, who loved woodworking, said he often went to the basement to make sawdust. My wife constrains me to the shed, but my grandfather would have been pleased with the amount of sawdust created tonight. I was power-sanding for over an hour. I thought the 36 grit sandpaper on the belt sander might be too coarse, but no longer think that is possible with the amount of material removed. I thought that pine being a "soft" wood would come apart easily--that wasn't true. I can't imagine how hard it would be with a real hard wood. It was a dusty night.
I drew some lines where it should be sanded, front center and about 4.5" back on each side, as reference points, and then tried to guestimate as best as I could. I'm sure it's not a perfect airfoil, but looked close enough for me.
Here's a picture of the post-sanding rudder:
(https://lh3.googleusercontent.com/rWUS0sZfyEe0gBmU9QgpFQh7H1WmamZzxhnYuW052YfpF3XHndOrvRsO_Kvr0b-ARr_pRxcnt1uj1oQeVeXADHXsKcRSI5asFgzZ4Lji-COotHy68DhSvGFF4lPw0ShehuDqM8UQC83mynyB3Ta8nNNtatADECvUV3gmCXs0iHkc4IFrdZSFKAxSLCXWke1EGTq9KChYBs1ZWtFD2o9zO1j80mbAQOnHUJ42QefLpSTZtAty8y_-ztAGlxcbQcxNV8k2l0072Bm_hugy2TR_81ekTxLul6_BBn9E5dKW-gScKDc_JnS06V9T2cZS6ftwY1fz_HDK3l6jqhet4zdx9q47eAl-xYiZxFpFOQXuBt8Q_2of3D0cNsjn8w7qTalN70ezaOyS8NhxOW9skQtdVSNPsQDuordbzjlfvpQkPcfLBYdCwawumv9JOgMLcB1coDJomAxbDp0QduEjsx61QBtgwwu931uoYcwwZ3cEBa4gJ9Ca1-7EmlbhkeDeOIsg5E-4v0O7x0Z4sb2lG7jKNOFLM0mSAs_gYz4NemS1WPNynNC7PDnYHNzOpSYZHnmlY1d_=w1758-h989-no)
After sanding was completed, I treated the wood with the copper naphthenate. I'd never used it before. The interesting thing was hearing the wood crackle as it was soaking in. I'm hopeful the wood remains attached.
One nice thing was the rudder has a hole for easily hanging for the treatment:
(https://lh3.googleusercontent.com/mghMvFde2iG-4bk-Rnz0bXEJMmDF1AVv19esxOX-3osGkFNpjtGDTKjXdnLTSoyX_Wdld4CGeVMXky2-XUh0kRlilw-YPmLcuPeREflb-WSUw0YaYPwaye75SdCeg6DcwkgnZhMqB-hqFuTLWXA4gIGo9zYKrT2A6HUTylk2TuI0mSIqd6q7pCztenY8wbYfcPZ58iYflYvBdTGWWi1ZByWFnBQAs7F0TCKMy0RnLbX_cZY_K4pIAOHgOA00EjbV25s2qOTdJo2voZWNL8zmMsZmF7IBj-mhDs45gpLgauwfIap-yMTzyHLXn8J8NwJkoykAAmvCeg07tvkUG2Vx6daEiqaLf66-XZQ8r1nuKDBeSTz8ljUxeqUXA0Sa3M3kaphqJ9Ry1rP-rGNoiO9RDvbYLNqwSvyas_9MKkTxsMQAcb2TTJvUxiiV5kJwsTGjspkyHVzUtvJ8PERa9D-W0xwN6MoP-qqaocYHt_GJ8UBHZVw6qqjmIMPM_MpFQDluf-mEPrBVvMmIfBWQDqvyzfyPMj2jUnoSwV7bOvkN0iwxDrgjQ22jNo5TmVXR8b8x97f_=w557-h989-no)
Next will be covering with fiberglass, unless I end up with a wing. My thinking is the wing could serve a downhaul function, and still keep contemplating the idea. Per wikipedia, the wing is helpful when side-force is required, but provides extra drag when running. I'm guessing the rudder spends more time doing the equivalent of running than reaching, and I should listen to Bob, but I want to keep noodling about it.
Tim
Many people have made the mistake of listening to me: You may not want to join that group! It's looking good! I really can't comment on the wing except to say maybe reserve it for your next project. Too many changes and you won't be able to tell which change is and isn't working. I can't wait to see the finished project: And just in time for Christmas- a nice gift for your boat.
Bob23
Are you sure this is the same "I DEMAND TOTAL ALLEGIANCE!!!!!" Bob23 going to the Chesapeake Bay Mid-Winter Gathering?
I've been trying to read to understand the design implications from this:
http://www.sponbergyachtdesign.com/keel%20and%20rudder%20design.pdf
Thus far, I've come up with my 13% foil thickness as percentage of chord and 33% maximum thickness location are good choices as long as the foil remains clean and smooth (e.g. break out the wax polish, no bottom paint).
There's something about elliptical rudders generating the least vortex drag, which clearly isn't going to happen. Hmm, still thinking about it....
Wow...It sure looks nice. What an interesting green color....Fiberglass? I'd love to see the leading edge of rudder. Great Job! How much time/labor do you have in the project? I might get motivated and make my own too! Tim
The green is the copper treatment which hopefully makes the pine wood last. It should be covered up by the time it's finished. The boards were pre-cut to 22" length at home depot, and setting up and glueing in place was really only like 30 minutes. The hardest part by far thus far was the sanding down to shape, which took a good 90 minutes. I prepped the fiberglass, but opted to take a night off tonight. I'm guessing maybe 5 sessions of 30 minutes each (side one, front edge, side two, front edge again, bottom and top?) and then however long sanding a smooth finish will take.
Ask me next week if it really did finish as planned. I probably should have started the fiberglass tonight, while I'm still allowed to work indoors.
Anyone have hints for how to put down fiberglass? I put the "middle" of the fiberglass on the trailing edge, that way it has a double layer on the leading edge where there is overlap. Getting the corners to work flat isn't very simple. Without a professional vacuum system, is there a best practice or hints to make it sound? I've done one side thus far, and man that stuff is smelly--admiral will probably not be happy when she returns...
(https://lh3.googleusercontent.com/ss0uswN_81bfDNdBwVXs_zmi6bTtibBPBcjtsK9jZlx-pkyv3qPVJg33bpHk0H-ppWfSKK-Oqe-NOXMl0JhGYrH9iYB3LqNdFv3WpEvqPhaPOaWZr3nIq7iBUEmQQk37DIRLwo98MJwb2sTy5DRiyC1eUOt0P8SIMiG5IIvK9w9If-JZq3-V73VbG2xJbF05uDm_p3fmo6ssF2AJxW7ohr5G6jj3BZEsN2XfQ0IEiWmB9kxDi0zSq8G7ptQkyWV65G6qGdUvw_-cK5I7593_FvlDRHGvGCe0Lxf-0Zve6D0YKt2xfS9fqHOoKvJec0oznXczGCyKHgRE_m_n5d1IWNelnDVy9AzuiGo3bGA2qrvP76bN0Q2273MhK6UpRHwVt7a_zZ6LGVJPJozRGukr-6A8oIC1SkXD9kzS1IlwxXxlcU62ZxgTg9Iry7xOJBtP9DWWP-sIMdeL9hK3jUnsYhXH-4emJoOpDxIiVuf-Z5hjLQ1qKW-BFr_mvL9LPSf4FYuKodH-qwSKTApCShS0M9NrWmbU6q14pxvjZp-M08SmVnqtatPu_bDmhE8R96xnE-hc=w1208-h679-no)
I know it's a bit late for this layer of glass, heavily radius the edges and put 'darts' in the cloth as you need, to get the cloth round the edges. (Darts as in clothing and not pointy things!). I also put the overlap on the leading edge.
Having said that it loks like you've done a good job.
Hmmm, darts look like they would have been helpful. They seem like a great idea.
Anyone have guidance on bubbles? Are they like death in fiberglass, or just things to avoid and fill in later? Maybe I should have watched a couple youtube videos on it first.
Possibly a different fiberglass product and polyester resin would have made rounding the corners a bit more easier.
Check out the video on Fiberglass selection.
https://www.youtube.com/watch?v=ioj1YBm6bJY (https://www.youtube.com/watch?v=ioj1YBm6bJY)
My lesson learned is that if I started over again, I would not have used the fiberglass mat as one big sheet, but cut it up into smaller sheets sized for where they would go. My edges, especially corners, are total messes, and not sure exactly how I will clean them up eventually. I suppose it's a good thing I have until spring to be ready. The Tap Plastic videos are pretty helpful.
With the snow and colder temps, and working in the shed because the epoxy smells really bad, this project has been going slowly. During the plateau, I had an idea on which I'd love to hear your thoughts. This idea comes from centerboards and a different set of boats (obviously).
The idea is to add about five pounds of lead cast into the bottom of the rudder so help ensure it doesn't float. I think that would be about a cup (volume wise) from my rough calculations. I think I can buy this for about $17 from the Amazon.com, and then melt it and cast it onto the bottom of the rudder, and then encapsulate it with fiberglass and epoxy.
What do you think? I've been avoiding foam to minimize the floating, and would adding lead ballast possibly help as well? Glad it's not summer, so I have plenty of time to work in this.
TimW
I bet if you tossed it in the bath tub, it would sink like a rock. You have a downhaul on it right? I wouldn't worry about getting it down to where it belongs if you have a downhaul. I have a tendency to rely on my downhaul to make sure that my rudder is in the right place because just hanging it from the pivot bolt won't get it far enough forward to knock down the weather helm. If you are concerned about cleating off a downhaul, I use a pop up cleat on mine. If the rudder grounds out, the cleat releases. Otherwise it holds the rudder in the down position even when hard pressed by the water.
I am rebuilding one rudder this winter and have built a new one for two of my boats. It is kind of fun isn't it?
Al
It's warming up, and I'm back to finishing up this project, because it has to be done before I can sail.
Question about laying fiberglass: What do I do with my imperfections where there is space between the epoxied glass and the wood? Do I sand out the glass and try again? I had a horrible shape on the bottom, as my glass laying technique over the corner sucked, so I sanded it out and tried again, which was better, but not great. There are other places (e.g. look at the trailing edge on the picture above) where there are gaps between the epoxied glass on the layer underneath. I'm finding that putting more epoxy on top doesn't seem to help. Any guidance from people who know fiberglass much better than I?
Thanks,
tmw
this is a project that has been on my list for years.
let me start by saying that i'm no expert in boat building, but i was a pattern/model maker for over 20 years and the fiberglass casts i produced had to be stable and strong.
this is how i would go about it...start by placing a long thin piece on the trailing edge, then a piece on either side, with the side pieces overlapping the trailing edge piece. next a long piece on the leading edge, overlapping the side pieces.
you're better off using smaller pieces that overlap than trying to cover the whole project with one piece.
with that said, it is also better to apply several layers of a lighter weight cloth than one heavy layer.
next, after sanding down any large humps use a good fairing compound to fill any voids and smooth out the surface.
now, for your situation, sand down the high spots and fill the low ones with epoxy. then use the fairing compound to create a smooth surface for painting.
again, i've never done this project, so maybe someone who has can speak up.
c.c.
tmw, having gone through this, a couple of options...
In this photo you can see where the fiberglass resin ate away the foam underneath (my bad for not testing prior).
(http://i1125.photobucket.com/albums/l594/CPYOA/com-pac%2016%20pics/BaBaLeLe/Rudder%20Project/Days%203-X/IMG_0235.jpg) (http://s1125.photobucket.com/user/CPYOA/media/com-pac%2016%20pics/BaBaLeLe/Rudder%20Project/Days%203-X/IMG_0235.jpg.html)
In the large areas, I cut through the fiberglass and used thickened epoxy to fill in the holes. You can see some of the hardened epoxy after being sanded down in this photo.
(http://i1125.photobucket.com/albums/l594/CPYOA/com-pac%2016%20pics/BaBaLeLe/Rudder%20Project/Days%203-X/IMG_0236.jpg) (http://s1125.photobucket.com/user/CPYOA/media/com-pac%2016%20pics/BaBaLeLe/Rudder%20Project/Days%203-X/IMG_0236.jpg.html)
In smaller areas, an option is to drill a hole of about 1/4" and use a plastic plunger or plastic bag with the corner cut to squeeze in a thickened epoxy paste which will fill the void (like cake frosting). Consistency is a trick you gain over time, and currently I'm getting much better at adding the right amount of thickener (current choice is wood flour) to get the consistency I want.
For the smallest of "bubbles," it may not be worth doing anything. The fiberglass has sealed over the gap and is now a solid layer (which is why no amount of resin on top will penetrate). You have to get under, or you can just leave it. With another layer or two of glass and resin, the likelihood of it being an issue is minimal. It's going to be hidden under paint anyway.
For my rudder, I used a single large sheet on each side with an overlap of about 1/2" at the nose. Fiberglass does not like to stick around sharp corners, and the heavier the glass, the more rounded the corner needs to be. Using the technique described by Carl is a good one for the trailing edge. Another choice is to lay down a layer of thickened epoxy before you lay the glass or tape. This will help prevent the small gaps/bubbles as you apply resin over the top.
In the end, it may not be perfect, and you can see the low spots on this rudder indicated by the remaining paint. With the thickness of the bottom paint I'm going to apply over the primer, I'm not sure how much will gained by trying to get it perfect before going out sailing again.
(http://i1125.photobucket.com/albums/l594/CPYOA/com-pac%2016%20pics/BaBaLeLe/Rudder%20Project/Days%203-X/IMG_0248.jpg) (http://s1125.photobucket.com/user/CPYOA/media/com-pac%2016%20pics/BaBaLeLe/Rudder%20Project/Days%203-X/IMG_0248.jpg.html)
-Justin
I'm right in the middle of glassing the new rudder for my sailing canoe. I did very much like you and folded the dry glass over the leading edge of the rudder and clipped it behind the trailing edge with clothes pins. My intention was to hang the whole affair by the clothes pins so that the leading edge would be forced to lay down tight. That didn't happen. Instead, I clamped it in my bench vise, and painted on the goo. I ended up with a couple areas where the glass didn't adhere to the wood on the leading edge. After it cooked off I carved off the fabric that wasn't adhered, and now today I intend to fill the voids with thickened epoxy. I am going to try using baby powder to thicken the stuff for the first time. I will make the goo thick enough that it will stand up and fully fill the void so that I can file it down fair. If you put enough epoxy in the hole it won't matter if there is no glass in it. The glass is mostly there to stabilize the surface like tape would do on paper. As long as the epoxy is thick enough, it alone will water proof the area.
If you have areas where the fabric floated up, you can sand that down fair as long as it isn't a huge spot and don't worry about going through the fabric. As long as it isn't a big area, the same applies. As long as the goo is thick enough, it will water proof the spot. I would not advise this on a large area like a hull bottom, but on small piece like a rudder, I don't think it is a big deal. If these defects drive you nuts, sand the whole thing fair and put another layer of glass on. If nothing else it will be good practice.
Al
So, for an update, I had the rudder finished glassing and ready to go. It was painted white, and seemed to work. Here is an installed picture:
(https://lh3.googleusercontent.com/yc77o_79aD9FlkeQymNOhAyrPS8zaWqZLf8jxsXFVn-8mlcINBJkrV4llyRtH2N6lK9Lxvib3MHJ7SiiMkbtrJVnlhMF6PGaxJaO6FfM3ZsyV5NM3KmOGO2guTqF6IvIXrhKG_0OdFhLqqU5bXVt5F7gbJf6TzwxR5r5JlneluT8N8bBW0Qdo04rwlP56oTElwqsR2eAmq08YPiIiAsNynAuvQcEIy0w1YP8763MzzYk92aBM_4R1-H_LUZzWXYrMMaKD97qtuy0q4_PC8jluzzclTahSZ2kNENtu8rE42hJzxzQol4QmFk58a8DqqY7RtrN4d3MO6VV4DaIYhL_MOWn7e4IfeHzAOu5zjIa6QYpXkvV2GzOK-7obhKm4qqt6HqvRDEnbCYsWsvHCz28JkmWIjJKZEASiKwA9Tr87uJqBEYlLqndTov49bA_6raoaVNsMJZ43a3kDcDaynnlntTgLjmq1GEFqL70B0G6sz8FKIjDQJm7o6u4D6LbLGnTzbhE-z54_5DEhVOLDhS8wbnDhtFQjMJYljB6Ot2dBEooQLhM9g9A478GdTVEWJT1hem0qtLOMlC275OzZlFh7fvVKytJXI25Cv8rwgMYzYAUIgDnykbl32t-TsaW3O7NGmFQVIv_V5edkplrpJ3oHl8OmpPUctsUN97rxdtqfbY=w1199-h674-no)
The rudder worked very well, easily controlled, and did occasionally rotate up, but for the most part stayed in the normal position (reaching over was pretty easy to push back down). I want need a method to hold it down, like others have built, as the next upgrade.
However, evidently my glassing wasn't waterproof near the trailing edge. The result was that one side warped off the metal blade.
(https://lh3.googleusercontent.com/g2ae4BfkVpkugart_zDU5bpiAoe99OFB7xdIovZUAYZmviKycm2hmyTgS9ISv8zbFJ7Z51YEAGq56DetnFK4xqUeN6btf7tu7eRFKtZFZLbIZfnAcSSJ086LdUMKftpCOURWSztMtsyiQ5kInQA0EGWqQoH37VxcI69DJuBXqLQuEYfNZVYW_n1HZzZOHCgzw7JUF83Wji20t62qouPfc8mtefE-esXgf6aZO_UsY-M7BFeGpfuCPnUyemV-v92DfGFsY3yxKUyxuPGjJXMQ_aPAINd0ddBPUFw0M7CDc_08xz6sYRXMW5473HjFN1c099ZfjYlJJQ3XGDTpaZet9TqnX3umY3HpBlRvbPwXjJlzY5x1iu-Ir3N9su4f-cbz62-BUVUXq0BBOc8A_02Jxm0lHtBEbi97gXg6glr-Y9YFLanPXmjUtPle5JrwY81nc9RoQV_pq8402UUzhZbFzzLxYVDUXC5u_KGUsnxRsdPFqDn5h7G78rec3cxZLH-xyTkO3rRXgZ7qbdcFR6YvYOa0qDiaWDpD_l_jZJy1kKEp--u9W5qS3NY6SLqSeC0n-4_wAJ2yQB8it2xxCyXv60UcJqMrn3sqSu9R_aHjhbSDYf-5HSQYT-vGcpS5TMCF_T87_Utx24FYjnIZRsdt8RndWKYJMntrwldKxEZ70Do=w380-h674-no)
Now I'll have to think about what kind of short-term and long-term fixes I can get in place, since it's no longer winter....
I am sorry to see that tmw, you put a lot of work into it. I wonder if some through bolts would work, and then some glass over that. When I did my rudder, I draped the big pieces of glass over the front edge of the rudder and brought them together at the backend. After it dried, I sanded it, and then I flipped the rudder over so the aft side of the rudder was up and I ran a few lengths of glass strips on that edge and let it dry. I then sanded the edges down to try to fair it to smooth. It seems to be holding up pretty well. Hope this helps.
Chris
Thanks, I'm thinking I could always wet it down and use clamps to force it back into shape. I sanded too much on the trailing edge, trying to get to a nice point (or relatively close). It's a good learning project--I had a suspicion the wood wasn't the best material, but was willing to try and learn as I went. It doesn't float as bad as a foam rudder probably would, but that is my current next best alternative (and probably much more work than clamping it back into shape).
Yeah, the foam in my rudder definitely wants to float! I think Bob23 made a wooden one, maybe he has some pointers.
The clamping back into shape did "work" at least for the short term. I used some fiberglass to patch back between the clamps, and that has been holding well enough, at least to get through some sailing effectively. I don't want to permanently trap air inside there, so at some point I'll probably have to remove all the work and start again, being careful to not sand so far that I expose the wood again.
Picture showing the "patches" along the trailing edge of the rudder in kicked up position:
(https://lh3.googleusercontent.com/UPYMfj2bJYhT6T84-2h-GUErJk2p01oEji5l_deLlgE0SHiqgy9ukdoDv33p3Kiys8HlTSKaPXRmsa4FR8J0yq5p8CtXc40Ki3PZ7DhCgsQqIMSg2M40Da1ZC5c8lVITBCTNp41ywndF_udi2QcjcJ9_kK2WCoWdinBJ4xi8tsbrgYuEs6-TUEyl_5V2Mlgt_RWvK5DGUb_KhAfiU-gNM4xb2m5Ug4xRGrd3qweWSNryMrQo3gLW-arCzwfFsM1fifKzqW7x6BfhJchBagF5a4SgmGbchlQ9U4xjhaYjQjo3YCqxHjOBxQZakDpeORU1O1Ajk4x9tdgdPIHKBnliQzlH53zHBhrA2BccIIWsX7uaTf0OKSji0XcJf7hJnhB31lYAymWj4pD9CMWaL8dFEvxP_MTAAIa1sKKrN-zmIbS0F70H4X36I_XI5r6uqF8B70WQ1Hz2nIUIOYp_GTCp4fACy5HQhhyjDPlv_NWHbDLa3KCVM0hA-palBYKraFc97aWMGFSJhAZ2M3hp_pE9wLIvJpv2wdadvP6pHq8kwN-ZIhs4naZWLKKuPtDPLVIh_hVQrdM-ONer-OJpdb7to6y5oWhzANrue6K0IzRuOnvvRyv4B5qQh8vxMEuT64CWbSB0cF4XxE-LrKeFIexgFtc5B3vPBYhPPFSr--pj7ts=w535-h950-no)