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PostPosted: Mon Jun 22, 2009 1:42 pm 
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Hey Tom.....I bought some West 105 Epoxy Resin and West 206 Hardener....graphite powder will arrive tommorow. Did I get the right stuff? :)


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PostPosted: Mon Jun 22, 2009 1:52 pm 
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AlanRV8 wrote:
Hey Tom.....I bought some West 105 Epoxy Resin and West 206 Hardener....graphite powder will arrive tommorow. Did I get the right stuff? :)


I don't remember the numbers but I'm guessing you did your homework when ordering. I'm sure there are other epoxies that would work fine too but I've never had a reason to go away from West System since it first came on the market.

You can probably get squeegees at Advance Auto or Autozone. It's worth getting them instead of using something makeshift like cardboard. They will be back where the Bondo is.


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PostPosted: Mon Jun 22, 2009 6:28 pm 
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I saw a video on rudder refinishing at Surf City Catamarans. He uses a roller, so I'll give that a shot. I sanded them first with 80 grit, after they dry I'm gonna use either 600 or 800 grit. That should make em as smooth as a baby's butt! :lol:


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PostPosted: Sat Jun 27, 2009 2:58 pm 
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Location: SE PA/ Chesapeak Bay
Over the years I've done maybe 6 or more sets of EPOv1 for myself and my friends.

As usual, Matt B is quite correct as the EPOv1's will degrade just from longterm UV exposure to look like those shown in the pics.

And I also use the WEST products ... but I hang them vertically .... coat w/ WEST ... and hang them out in the sun to cure .... then wet sand (200 ... 320 ... 400 ... 600 ... 800 ... 1000 .... 1200 ... 1500 ... 2000 ...) Studies have shown you can not make a rudder/dagger board too smooth ... sand until water does not "bead" and runs off leaving the blade dry. ( I used to race ... alot)

Thoughts: Considering that decent replacement blades were not availible for the EPOv1's until the "new" EPO's and the cost of the "new" EPO's ... I keep my blades in my sailbox. Also the sun/UV's also can weaken the rudder head which is not covered by the covers availible ... but since most damage to the surfaces of rudder blades happen inside sailboxs from chaffing/rubbing together I use covers (since I can not sew I purchased covers from Murray's but I've seen lots of homemade covers ... "fleece: works best since that material will not hold moisture. (Remember to rinse your rudder covers periodically since the salts from salt water can build up in them and that allows the retention of moisture) I installed the "20's" style tiller/crossarm connecters so I could easily disassemble the rudder system and place it in my sailbox using the minimum amount of room and having the rudder system still in alignment when re-installed.

If you do trailer w/ your rudders on, consider that most-likely you will be in violation of most states "overhang" laws if you do not have "RED" on the ends. Get Rudder covers and a mast cover that have "RED" on the ends ..... they just may save you from some legal troubles if someone runs into you boat/trailer.

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PostPosted: Tue Jul 07, 2009 12:50 pm 
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I finally got around to putting a fresh coat of epoxy on my EPOs. I applied it with a roller, and much to my surprise, the roller left a nice, very glossy finish. I don't think I'm even gonna sand them at all. What surprised me was was how HOT that stuff gets when the reaction gets going. I wasn't sure how much it would take to cover both rudders, and I ended up mixing up WAY more than I needed. About 15 minutes after I finished rolling it on, I found the pan I mixed the stuff in was actually SMOKING! It was too hot to pick up for about 2 hours...LOL. It took about 16 hours for the re-coated rudders to set up completely, overall they came out really nice. Is sanding really required? :lol:


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PostPosted: Wed Jul 08, 2009 10:47 am 
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AlanRV8 wrote:
Is sanding really required? :lol:


Yes....before you topcoat them. I did the same as you on my first EPO refinish job. They came out so smooth and shiny that I stopped there. A month of sun and they're chalked right up again....epoxy will not hold up to UV (see M. Bounds post above). Now I topcoat mine with rattle can "epoxy" appliance paint.....relatively cheap and easy to use/recoat as necessary. Rudder covers help a lot, too.

Jerome Vaughan
Hobie 16
Clinton, Mi'sippi


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PostPosted: Wed Jul 08, 2009 11:48 am 
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rattle 'n hum wrote:
AlanRV8 wrote:
Is sanding really required? :lol:
A month of sun and they're chalked right up again....epoxy will not hold up to UV.


What chalked up so quickly was the amine blush.

When some epoxies harden, a byproduct of the curing reaction rises to the surface
appearing as a greasy, waxy layer. On contact with high humidity or water, this coating
turns into an opaque white smudge (during or even after cure) which turns into dry chalky
powder with time. This 'blush' will not wipe off easily with thinners or solvents. It can only
be dry or wet sanded after the epoxy completely cures.


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PostPosted: Wed Jul 08, 2009 1:33 pm 
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So I should wet or dry sand them and do one more coat of epoxy with graphite, then re-sand until smooth? Also, at high speeds, the rudders make a humming noise which I assume is cavitation. I fly, and this to me indicates drag which is not a good thing. I slightly thinned out the trailing edges before I epoxied them, see if it quiets them down.


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PostPosted: Thu Jul 09, 2009 10:45 am 
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For the record, I understand the amine blush, and maybe the "chalked up" term i used was misleading. But it did not take long at all before my rudders were chalky black. As in they left chalky black crap on whatever they touched. As in chalky black in appearance like the photos above (just with no fibers showing). Perhaps I used too much graphite powder, but that I doubt. They were slick and hard upon completion, but just didn't stay that way. I used the same procedure when I refinished them again later except for adding a topcoat of appliance paint.....no problems for the last three years. After all the work put into refinishing, I strongly recommend topcoating with something other than epoxy for UV protection.

Jerome Vaughan
Hobie 16
Clinton, Mississippi


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PostPosted: Tue Jun 22, 2010 8:13 am 
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Genmar, did you use any filler or just the resin and hardner, along with the graphite for color? Or does the graphite act like a filler?

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PostPosted: Tue Jun 22, 2010 8:52 am 
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http://www.youtube.com/watch?v=jNwMgX48uwQ

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PostPosted: Tue Jun 22, 2010 1:45 pm 
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Thanks Rich. I have been watching that video. They used West System 404 filler. I was just checking to see what you advocated. Your post implies 404 is the way to go.

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PostPosted: Tue Jun 22, 2010 2:32 pm 
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Thats a Surf City Catamarans video. I was just getting it up there for you. I have seen Jeremy's work on old EPO's and they come out great.

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PostPosted: Wed Jun 23, 2010 8:46 am 
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The 404 filler is just used to fill the larger gouges made by the castings etc. I use it as a high density fairing compound. Matt's right about amine blush 'chalking'. Ive had a problem with the coating yellowing. I now use a 'super clear' epoxy and make sure to mix in at least 10% graphite powder into the epoxy. The graphite inhibits UV from attacking the epoxy. I might even go up to 15%, but read the directions.

I like to sand them down to 1200 and buff them to a shine. Stock, they were just wetsanded to 800 I believe.

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PostPosted: Wed Jun 30, 2010 6:41 am 
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SurfCity, so the super clear final finish, with graphite, avoids the amine blush issue, as I understand your post.

West Systems 207 hardener is supposed to provide a clear finish (overcoming the yellow tint of the 105 resin), is this what you used? If not what did you use to provide the final finish? Also, may I assume that it is the final finish that needs to be like this, and one can simply use West 105 with the 205 or 206 hardener on the lower coats?

Picked up an 1985 H-16, with EPO's and they need to be refinished rather badly. This is my first experience with a Hobie. They are showing a lot of fibers, but still do not feel them, so they are not too bad. I was planning to just use the West 105/206, sanding as recommended here in the forum, then a final coat as you describe.

Thanks to all for the helpful posts.
Image

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