Shearwater 16 Hybrid - sanding the hull

I finished filleting and taping the inside and yesterday I fiberglassed the cockpit.  I did end up taping the cockpit - didn't see the message in time but I am not concerned about a little extra tape. 

So now I am moving on to sanding the hull.  When I put the panels together - some of the epoxy leaked out on the outside and formed the impression of the plastic - so the area around the joints is not completely smooth.  Should I be worried about how this will look?  Will is disappear when I put more epoxy and fiberglass on it?  I tried sanding it and it doesn't smooth out easily.

I couldn't figure out how to post a picture so I created this blog so that you can see what I mean.  Let me know what you think.

4 replies:

« Previous Post       List of Posts       Next Post »

RE: Shearwater 16 Hybrid - sanding the hull

Hard to judge from the pics, kts, how much the epoxy is proud of the surface, but if I were you I'd definitely sand it back.   It won't take long and if you don't and it spoils the final appearance (a) too late (b) you'll be forever kicking yourself!   Use a fairly coarse sandpaper ona solid cork or wood sanding block (others may recommend scrapers) and sand only in the direction of the grain.   You may or may not - depending on how fussy you are - want to do both sides of each panel, that is, what will eventually be the inside and outside of the hull.

The final 'glass and epoxy coats will then take care of any tiny remaining irregularities.

The best 'tool' to use to judge the smoothness of the final joint area is not your eyes but your finger-tips - just run them over the joint lightly until you can feel that everything is smooth with no difference at all between the joint area and adjacent ply.

Enjoy the rest of the build!


RE: Shearwater 16 Hybrid - sanding the hull

Thanks Wordsmith. 

I appreciate your advice.  The joint does not feel smooth yet so I will work on sanding it.

RE: Shearwater 16 Hybrid - sanding the hull

You should go over the whole hull before glassing. Starting with 80 grit sandpaper and finishing with 120 or 220. Smooth out rough spots like that, and round over the edges at the keel and along the chines so that the glass will conform to the curves.(The glass will not conform well and will lose strength if the edges are too sharp along the chines and keel.)  The shearwater manual recommends rounding over to about a 1/4 inch radius. A fairing board is useful for this, especially for rounding over the keel line near the bow and stern. You should be able to clean up the puzzle joints so that there is not much visual artifact outside of the line of the joint itself. But be careful not cut through the outer veneer when you work on that or it will leave an ugly mark.


Ogata (eric)

« Previous Post     List of Posts     Next Post »

Please login or register to post a reply.


Follow us on Instagram: @clcboats & @clcteardrop