Tape and then use any fine tooth saw and you will be fine. You will need to sand the edges anyway and then seal with epoxy.  I find that after cutting and gluing in the  spacers, I clean up the lines with a very small plane, then a good bit of sanding with a small backing block for the straights and a large diameter dowel for the corners.  After epoxying I have sometimes had to come back and cut a bit more clearance. I leave the wider piece that supports the gasket to late in the process.

If you search the forum there are many threads on how to do the hatch and coaming (just a hatch spacer and lip done upside down.

Hope that is helpful

Ed

Thanks, that's most definitely helpful.

Yes, I searched through the forum but didn't see this issue addressed, and I really don't want to screw this up at this point.

Follow-up question: I am worried about the cut-out falling into the hull, and breaking off a piece of the surface in the process. Did you make the cut in multiple segments, leaving small tabs to stabilize the hatch-cover?

Maybe I've just been lucky, but I've done it four times so far and never had a problem. First, I cut the hatch cover out BEFORE assembling the deck panels and before any fiberglassing. I use a 1/16-in bit in an electric drill to drill maybe 4 or 5 holes very close together along the line of the hatch cutout, then carefully angle the bit to "connect the dots". Then I use a fine-tooth saber saw blade to carefully complete the cut all the way around. It's worked just fine every time.

Jim

I think you have a highly exagerated idea of how fragile this stuff is.  These kayaks bang into rocks, fall off cars, etc without major damage. Dropping a hatch into the opening is only a fall of 12 "   No time to get up any speed.  If concerned use a little tape stuck on the hatch and folded over to hold it up for the last 3/4 " of the cut.  

I have done the drill small hole route and also the tilt a saber saw forward and then slowly lower the blade into the wood till it works its way through. Both work. Any minor dings can be sanded out.  

I never cut the hatch before assembling panels and epoxying because I want the glass to help hold the matching curve in the hatch.  

I recall one picture where a hurricane threw a CLC kayak nose first into the back wall of a car port.  the boat stuck 1/2 way the wall with the first 3 feet sticking out the other side.  If I recall the owner pulled it out and went kayaking. 

A little epoxy, a little sanding, a little varnish and you can fix anything.

Ed

Thanks for all the advice. I feel more confident now about the procedure.

BTW, I wasn't worried about dinging up anything if the cut-out falls into the hull. My worry was that it broke off before the end of the cut and tearing out a few fibers near the cut. Anyway, I'll be careful.

Thanks again!

Besides the tape, you could also use a utility knife with a sharp new blade to cut the outline of the hatch. This will break the fibers on the top layer where the cut line will be so there sould be little or no breakout.

I don't know about other models but when you cut out the back hatch on the wood duck 12 you will have to deal with the temporary bulkhead. It is thin stock but if you used the suggested stiffener your jigsaw will dance arround when you hit it. Just a heads up.

If you're cutting a glassed deck, instead of bare wood, you probably don't want to be using a pull saw. As it comes up through the wood and the glass, it will lift the glass fibers from the wood. Normally a light sanding should fix that, but there's always a chance of a larger delamination that would be harder to fix.

Even though I love pull saws and have always used them to cut my hatches, in your case I'd recommend a standard saw.

In case it would help, here's a link to how I cut the hatch for my WD12. Good luck,

Laszlo

Hatching a Wood Duck 12

I had more time invested in centering for the cut than the cut itself.  Once I used the Perot method of measuring twice or more I drilled two hole at the center point fore and aft. Placed the jig saw in and styed inside my lines. Easy and onto the doubler stiffeners.  The direction to apply a filet to the bulk head was a concern.  I cut two pieces to match the radius and propped them upward to fill the gap on the aft bulkhead and add stiffnes to the area where one enters the kayak. I turned the boat over to prevent runs.  While upside down I will apply additional fillet material with wood flour thickened epoxy.

All good suggestions above.

I used a sabre saw with a sharp blade to cut my hatches.  I taped the surface before to avoid tear out.

I angled the saw on its front feet, slowly started the blade, and let it slowly pierce through the deck.  Put some cardboard under the front feet to add protection and hold the front of the saw to steady it.  I performed a test on the waste part of the cockpit recess first to make sure my hand would be steady enough for this scary procedure.

Worked perfectly without tear out.  I was actually very surprised at how easy the cutting went and how fast it happened.

Covering the bottom of your jig saw with masking tape (the blue stuff seems to slide nice) before using it on your build helps prevent scratches on the deck.

If you tape the hatch behind the cut it should prevent it from twisting at the very end of the cut.

Amen to the temp bulkhead on the WD12. I couldn't imagine why my jig saw jumped out of the cut and snapped my last fine blade until I finished the cut with a utility knife (which takes a long, loooong time) and saw the offending lumber. Fortunately the line of "stitches" the stump of the blade left as it danced across the deck did not show on the finished deck.

I'd rather be lucky than good.

I am about ready to cut my first hatch, and this thread has been very helpful.  I'm planning to use the CLC bonsai saw, and to go verrrrry slowly.  Tape on both sides of the cut sounds like a great idea.

I am wondering about the pros and cons of cutting the hatch before, or after, glassing the underside of the deck?

Thanks,

Alec