Cog Joints on the First Tie Beam – green oak barn

Saturday 16/1/21

Today we started by completing the mark-up of the cog joints between the tie beam and wall plate that we started marking up yesterday.

Tie Beam Cog v2

Then we cut the joints. We worked at our own ends of the tie beam – Ben had the wet end! Here’s a time lapse of the whole process.

Here’s a summary in still pictures. Completing the mark-up.

Cog joint mark-up - 2

The wall plate part of the joint (the hole in this joint is the mortice for the post that will sit below the tie beam).

Cog joint - wall plate

The tie beam part.

Cog joint - tie beam

Both parts of the joint pre-assembly.

Cog joint pre-assembly

The cog joint assembled at my end. Note the gap at the top of the joint – this is to ensure that the tie beam stays resting on the bottom on the joint when the wood shrinks.

Cog joint assembled - 1

And at Ben’s.

Cog joint assembled - 2

The tie beam in place.

Tie beam in place

At this point, Ben re-established the reference points on the jointed tie beam.

Re-establishing reference points

We then disassembled the tie beam and wall plates, turned the tie beam on its side and laid up the posts ‘under’ the tie beam so that we can mark-up and cut the braces that will join the posts to the tie beam. This was tricky as, obviously, it is not possible to put the wall plate in place. In place of the wall plate we used spacers of the right size to hold the post in the right position relative to the tie beam.

Lay-up the truss and post

With the posts and tie beam laid up correctly, tomorrow we will start by marking up the tie beam braces.

Lay-up the truss. post and brace





This entry was posted in DIY, Green Oak Barn. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *