Best scarphing method for frames?

[Seagreen]

Hello campers!

I'm about to start scarphing some frames, replacing the bottom ends which have gone soft and in some places, disintegrated.

Now as the flexing of the hull at this point is 'inward/outward' not 'fore and aft', so I wondered if there was any real advantage in having the face between the frames horizontal (one frame on top of the other) or vertical, so the frames are scarfed side by side? Is this clear? I Intend to use epoxy to glue the frames together and bolt through the scarfe. The only advantage I can see is that the scarfe could be bolted through the planking if the scarfe is horizontal.

Any thoughts?

 

[ccscott49]

I would go with the horizontal scarfs, easier to get the right shape and you can bolt through the planking or screw through from the outside, making sure there is no glue between frame and planking.

 

[Poignard]

If you want to go the epoxy route, have a read of "Wooden Boat Restoration & Repair" published by the makers of WEST epoxy and available from Wessex Resins Ltd, Romsey. It shows you how to do a repair in-situ.

Alternatively, you could "double" the defective frames by fitting new ones alongside the old. This is a very common type of repair seen in old wooden boats. I once had an ancient carvel dayboat that almost had two sets of frames as a result of this technique; when I sold her she was approaching the stage of needing "tripling"!

 

[jhughes]

A recent copy of wooden boat magazine had an ingenious jig for routing out the scarf on the frame in situ, sorry I don't know the issue because it was a free digital issue that I read online on the wooden boat website (skinflint that I am).

 

[JREdginton]

[ QUOTE ]
you could "double" the defective frames

[/ QUOTE ]

Getting technical they are called 'sisters'. I wounder if triples are call 'sisters in law' /forums/images/graemlins/wink.gif

 

[Seagreen]

Can't double the frames as I have 4" of concrete and scrap to hack through first. My efforts as of sunday afternoon are an inch deep into the scrap. I'd show you the photo but can't work out how to display it.

I'm having to dig out the hole then replace in place. A hard slog so far.

 

[ccscott49]

To scarph in new frames, I would step the old and lay in two or three layers of material glued together, makes them easier to bend to shape. if you understand what I mean.

 

[Seagreen]

Like "lamination in place", as it were? I'm thinking of laminating the replacement frames off site and then fitting them exactly. I think this will be the easiest method.

 

[ccscott49]

Yes, thats what I was thinking, but if you can get an accurate template, then no worries, do the job off the boat and them fit them, with stepped scarfs.