Shaping & fitting new deck boards

[Swiftershifter]

I am undertaking the replacement of the foredeck on a 1955 Wolverine runabout with mahogany planks and caulked seams. Straight planks and perimeter planks are all rough cut and now I am trying to determine the best approach to getting the final shapes for the perimeter pieces and where the straight planks meet the perimeter. I can use a trim bit in a router to shape the outside of the perimeter to the gunwhale. I am concerned about shaping the inside of that arc as there is no way ro stabilize the router so it won't 'rock', leaving a divot on the inside edge. Maybe I need a template. Also, there is the issue of fitting the deck planks to the curved perimeter piece.

My thought regarding the caulk seams is to route a 1/8" x 1/4" deep rabbet along each edge prior to unstallation.

Suggestions on how to proceed are greatly appreciated. Thanks.

[Fuzz]

I am not the right guy to help you but I bet a picture of what you are doing would be a big help. And welcome to the group.

[fallguy1000]

I really prefer working with a belt sander for odd shapes and radiuses. Templates from cardboard can help. Lines on the board. Of course, no sanding where you need hard 90s, but anything on the edges should be hidden by gunwhale and caulk. No?

[TomW1]

Use a router table to route each edge of the planks to get an accurate cut on each board. Lay each board down wear they go and mark the back 1-20 or what ever so yoy know wher they go back down. Also left/fight soo you know which way to pas them through the bit. You can also buy a rabbit bit for a bouter if you are not just making a groove for the caulk.

Good luck, Tom

[jonnymac]

Like this boat? This boat has holly strips in between the mahogany, but is this the wood layout?
https://youtu.be/kbwM0T4xlO8

if it has a perimeter piece that is curved on the inside, then i would expect to fit each board individually marking the curve, cutting it, and the. sneaking up on the fit with a combination of hand plane and belt sander. Then temporarily attaching it, and moving on to the next piece. I’m not sure if you should start in the middle or at edge. my gut says the middle.

after all the wood fits together and looks good, I would mark the inner edges. Set up the router table with the bit where you want it using feather boards to keep the cut consistent and run all the caulk groove all at the same time. This will ensure that it is all exactly the same. Since it will be very obvious with even a small deviation.


And I would think about finding a wooden boat forum where there are people who have done this specific work. There are lots if great people here who have done crazy fiberglass boat repairs but wooden boats are a different animal. And experience is going to be key for a good looking boat.

Here are some relevant resources I found.
https://youtu.be/wm0FFTeiOFs
https://youtu.be/kbwM0T4xlO8
https://youtu.be/OsMGueZVrJ0
this next one at 6:30 has a pretty cool tool that could be helpful.
https://youtu.be/picVdP1IRZ0

[Swiftershifter]

Thanks for all the great responses. It seems that the course of action I am undertaking is what most have recommended. Make a template and proceeded with a lot of sanding and close fitting. I had hoped that there might be a way to use the router along the sheer line to get the outside perimeter shape, and then replicate that for the inside edge, but not to be. The belt sander is the answer. I have the first couple boards shaped for the perimeter. Once the perimeter is done I'll complete the interior deck boards, route the edges and caulk.

Thanks again, your responses have been very helpful and reinforced my thinking on the proper approach.

[jonnymac]

if you use the tool or something similar i linked in the one video above it will help you trace the outside edge to the inside edge a little easier. then it’s “just” shape to the line. It could be done with a router to follow the outside line with a custom base plate made from acrylic. Similar in function to this. https://woodhaven.com/products/woodhave ... f1EALw_wcB

Thanks for all the great responses. It seems that the course of action I am undertaking is what most have recommended. Make a template and proceeded with a lot of sanding and close fitting. I had hoped that there might be a way to use the router along the sheer line to get the outside perimeter shape, and then replicate that for the inside edge, but not to be. The belt sander is the answer. I have the first couple boards shaped for the perimeter. Once the perimeter is done I'll complete the interior deck boards, route the edges and caulk.

Thanks again, your responses have been very helpful and reinforced my thinking on the proper approach.

[fallguy1000]

The trouble with routing is chipout and overcutting and that the router hides the line you so closely desire to see. If the sander chips out the board; it was already weak. Sander is how you close fit strips in the football shape of a strip canoe. Maybe give us a picture when you get on a bit.

[jonnymac]

The trouble with routing is chipout and overcutting and that the router hides the line you so closely desire to see. If the sander chips out the board; it was already weak. Sander is how you close fit strips in the football shape of a strip canoe. Maybe give us a picture when you get on a bit.

that is why i suggested the clear acrylic base. you can see your line just fine. also, most wood sold as mahagony is relatively chip out resistant assuming going proper grain direction. Also, with a quality spiral bit from whiteside router bits its going to be better.