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I have at least 8 frames to replace starting at transom. Boat is upside down and Garboards are removed. (note: replacing keelson also-see other posting for input) Frames have single screw and nail at keelson. I'm not sure how they are attached at top-can someone tell me?
Frames appear to be 1 inch x 5/8 inch rough sawn white oak. Is this correct?
I know I need air dried wood.
Should I buy quartersawn 5/4 think and rip 5/8 inch strips?
How do I know if I'm buying heartwood?
The plan is to steam frames and feed them down next to frames to be removed. Once set I will remove old and replace.
Alternative is to remove one frame at a time and put new one in.
Suggestions please.
Thanx

You want to use all heartwood white oak. Heartwood is darker than sapwood. Sapwood is the band of wood on the outside portion of the tree.
Ribs stock is not rough cut as far as I have ever seen. It's surfaced smooth and top edges are beveled a bit. Just copy what you have in the existing boat.

Air dried is best for bending frames/ribs. You can use kiln dried, but soak it for a week or two prior to steam bending 'em.

Planking is attached to frames with screws at each lap joint. You will have to sand off the paint on the planking to find the puttied over screw head. Dig out the putty with an awl and back the screws out.

The frames are screwed from their bottom side into the sister keelsons (stringers). The only measn to get those screws out is to remove the garboard plank.

Andreas

Andreas
What is your thought on leaving (cutting back to good wood) frames and installing replacement next to old. I would attempt use the machine screw holes to screw new frames into place. I would mirror any such repairs at opposite side.
Still wondering what areas of attachment at deck area?
What type of cut should the frames be: quartersawn or flat?
Also considering additional frame material to tie into keelson on bottom. These would lay in between frames on bottom, using machine screw holes, but not turn up the sides. This will give me additional fastening into keelson.
Thoughts

Sounds like your latest thought is to "sister" frames. That is to add a new frame next to the existing one. This is an acceptable means of repair. As you mention, make sure you get rid of ALL the old decayed wood.

Frames are screwed to gunwale framing just under the deck covering boards. Or vice versa.

Quartersawn is probably better for bending stock.

I am not sure I understand your last stement. You want to add another short frame inbetween the existing?

Andreas

Andreas
Short frames, possibly length of garboard and first strake, tied into keelson for additional strength (bottom to keelson). Necessary?

I don't see a need for adding short frames. It can't hurt. Just adds weight.

Andreas

Here's a little schematic of how my gunwales are constructed:



In order to remove a frame, you have to take off the inner solid mahogany rail. (NOTE: All of this assembly is capped with a 1/4" mahogany plywood side deck that must be removed first.) That inner mahogany piece is screwed into the oak piece, and the screws are covered with wooden plugs. See my other posting on the easy way to remove plugs. On my '57 Sea Lancer, the position of these screws varied, some toward the top, some toward the bottom of that piece.

Once that mahogany piece is removed, you can see the exposed screw heads that hold the entire remaining sandwich in place. These screws go all the way through the oak piece, the frame, the plank, and they hold the outer mahogany gunwale piece on. I assume one of these pieces, probably the oak, is known as the "sheer clamp" but I'm not sure.... Anyway, you can't completely remove the outer mahogany piece without "unsandwiching" the entire gunwale, losing all structural support in the process. Again, I can only speak for my boat, but the sandwich screws are only placed on every other frame. This means that the top of the alternate frames is unsecured; the frame is held in place only by the screws through the planking. Of course, the tops of all the frames are in the sandwich and can't go anywhere anyway.

My frames are just over 1/2", but shy of 5/8", more like 9/16" thick. The back face (against the planking) is rough sawn, not surfaced. You can see the swirls from the sawblade. The exposed face and edges are smooth, with about a 1/8" radius on the exposed corners. The tops are typically beveled a little as Andreas said. My assumption is that they were inserted into the boat long, then sawed off in place.

From what I can tell, they didn't originally pay a lot of attention to the quartersawn/flatsawn/etc orientation on the frames, but it's a little hard to tell by looking at the rough end. I think the main thing is to avoid grain "runout", meaning you want the grain to run parallel to the long edge of the frame. Otherwise, you risk a split either while bending or - worse - later while in use. I believe Sam Devlin (http://devlinboat.com) says in his book that quartersawn wood is tougher to bend, but that may not apply to steambending. I think he was referring to cold-bending a piece like a gunwale, sheerclamp, or rub rail.

Hope this helps a little,

-wte

Now that I have my boat flipped and can see things from a different angle, I've found that there are more screws holding the outer mahogany piece in place. There are screws from the inside, running through only the planking and into the mahogany, spaced 12" (in every every other frame space).

-wte