John:

I am building a Mill Creek 16.5 and I have also built the Passagemaker. The epoxy 'soak' at the scarf joints will disappear when the rest is coated with unthickened epoxy. The Shear clamps, according to my Mill Creek manual, are long to enable you to trim the ends easily where the meet at the bow and stern.

Regards, Alan

It sounds like you made a nice clean scarf joint - something that is not easy to do. That 1/16" line will show up dark, though, as will any other kind of joint you might make. My opinion and practice is that plywood should always be painted, which is one way to hide the joints.

I have scarf joints, I had epoxy seep on the joints, sanded them down, and stained them again.  Now that they're glassed, I can hardly notice the scarfs.   Esp. the darker stain (mine is two-toned)  The boat is looking really nice.  I've got to fill the weave one more time and sand it down, then do the hull.  My carpenter friend Dave made the scarf joints for me.  He stayed with the puzzle joints, and he is going to paint his.  But I think mine looks really nice.  And like I said, the scarf joints look great. 

Many thanks, gents, for your input; I very much appreciate it. The majority of you (thus far) seem to think that the joints won't be an aesthetic concern after glassing/varnishing, and that's a relief to me.

Although I appreciate that painting the hull would totally hide the joints, I really am determined to varnish in order not to mask the beauty of the wood.

Thanks again,

John

John,

For scarfing wood-to-wood joints you probably used a thickener.  I used the silica equivalent shipped by CLC as part of the kit.  The thickened epoxy does have a color that will show through the glass if you do not remove it by sanding. It will apear white if thickened with silica or brown if thickened with wood flour.  The thickening agent, however, remains on the joint surface and does not soak into the wood.  So, as mentioned above, any epoxy that soaked into the wood will not be a problem but make sure that all of the "squeeze out" glue has been sanded away.

Tim 

Thank you, Tim. Will do.

John

This is my first time building a boat and I got a little nervous when I uncovered the dried scarf joints and found quite a bit of epoxy overflow. I am using 120 grit sandpaper to sand the dried epoxy overflow from the scarf joints on my Chesapeake Double. 

I just want to make sure that I don't sand too much.  The joint is now sanded completely smooth, but there is some remaining epoxy that I could continue to sand off, but I don't want to "take away" too much of the plywood and make a depression at the joint.

This forum gives conflicting advice on whether or not the epoxy (plus silica) will show up in the final varnishing.  I will let you know how mine turns out.  I am only going to sand the epoxy smooth at the joints, not competely remove it.

One comment: I've found scrapers (I bought the ones sold by CLC) to be great for removing epoxy on joints, drips, etc. Much more controlled than sand paper--you can shave off the epoxy without sanding down the wood around it.