Ch 17 sheer clamp planing

After a 6 month hiatus I am back to working on my Ch 17 and am in the process of planing the sheer clamps - with some questions.  My understanding is that, except in a part of the midsection, they should be planed down to the point where the outsides just touch the plywood hulls - is that correct?  I may have installed the sheer clamps excessively proud of the hull and while I have a decent bevel in the bow and stern, I have what  I suspect is far too much of the sheer clamp exposed.  If I keep the angle (problematic?) I assume I can eventually get them down as far as the plywood but am wondering if there is a trick in doing this more quickly than planing a fraction at a time - and also losing th e angle in the process.?

Also, how important is it to maintain the proper radius angle at any given point. I seem to have a lot of high spots and am having trouble geting the template to lay pretty flush across the sheer clamp.  I havent gotten yet to the point where I need to plane into the plywood in the midsection, with respect to which I am lready suffering from some premature anxiety, but that may be the subject of another post.  Thanks in advance. bruce




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RE: Ch 17 sheer clamp planing

Well,  how are you going to meet deck plywood to hull plywood if you leave the shear clamps proud of the hull plywood?  How are you going to have good bearing and joint adhesion if you have high spots on the proud shear clamp?  Epoxy can only fill so much.  You still need good joints.  Unless you rabbited the shear clamps you need to follow the design and make the deck over lap to the hull. Better joints are stronger and provide a waterproof seal .

High spots when planing the clamps................put the radius guage on the clamps. It helps if the center of the gauge is always centered along the center line so you measure with the same part of the guage each time. Take several readings mark the high spots with a pencil. After say 2-3 ft of high spot marks plane them off.   I have several planes from small to big but my favorite tool for this is a belt sander. Sand, plane, whatever then check again. Repeat the process.   

Not having the proper radius may give you some flat spots in the deck. Or bumps and dips.

RE: Ch 17 sheer clamp planing

Hi Ruach! In the build manual for the 17LT (I think it covers both 17 and 17 LT it clearly says on page 105 

"When finished the top of the sheerclamp will be planed completely. You will need to plane into the plywood panels along the centre section, with the greatest depth at the deckbeam. From the deckbeam forward and aft, this bevel will roll back to level with the top edge of the plywood panel."

I hope that helps. I built my 17LT earlier this year and I did indeed have to plane into the plywood side panels to get the deck panels to fit well. 

Hope this helps.

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