I have some old chairs. I think they're oak but at some point, they've been allowed to get wet at the bottom of the legs. I'm looking for ideas on how to go about repairing this damage as I think they're worth saving. Thanks.
Repairing a chair leg
- Thread starter Rufus
- Start date
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Cut back to good wood and use the off cut to size up some new wood ( looks like oak to me ) mark centres of legs and drill hole for a suitable dowel,, mark and drill centre of repair piece and use a quality glue ( tightbond dark) and assemble- your repair piece should be slightly oversized so you can plane it to shape when glue has dried. a 2nd option is to use a 3mm pilot drill and drill through repair piece into existing legs and use a long brass screws to secure each repair piece to the legs . The screw will act as a clamp and won’t be seen once complete. take note of any tapers in the original legs and keep this in mind when sizing the repair pieces . Sand -stain-varnish etc to your preference and sit back (on ya refurbished chair lol 
) and drink a cold beer and marvel at your work.
) and drink a cold beer and marvel at your work.rogxwhit
Established Member
How accurately can you drill into end grain? And I wouldn't use a dowel joint on something that can get as highly stressed as a chair leg. I'd want to use something like a scarf or a long grain half lap, and pay good attention to the faces to be glued to get good contact.
Clamp overnight - no screws needed. If the new wood's slightly oversize you can dress it back to the line to finish later.
Clamp overnight - no screws needed. If the new wood's slightly oversize you can dress it back to the line to finish later.
Phill05
Established Member
This is how I would do it, a little more time to make but you would never break it apart.
Inspector
Nyuck, Nyuck, Nyuck!
A simple scarf joint (as long as you can reasonably make it) held with good glue is enough. Make the replacement piece to match the grain but a little oversize in case it shifts a little while glueing.
Your other option is to get some of the thin epoxy used for consolidating rotten wood and harden it up, leaving it as is. The epoxy won't take stain etc so you will need to shade your finish to match the rest of the wood. A little easier is to use thin cyanoacrylate glue (CA, instant glue etc) to soak into the wood. Get a good quality glue that is fresh like the stuff pen turners are using to finish their pens with. If they don't work then you can cut it for new wood.
Pete
Your other option is to get some of the thin epoxy used for consolidating rotten wood and harden it up, leaving it as is. The epoxy won't take stain etc so you will need to shade your finish to match the rest of the wood. A little easier is to use thin cyanoacrylate glue (CA, instant glue etc) to soak into the wood. Get a good quality glue that is fresh like the stuff pen turners are using to finish their pens with. If they don't work then you can cut it for new wood.
Pete
Richard C-D
Established Member
Hi Rufus
I've done this type of repair hundreds of times and would go with the scarf joint Inspector recommends but I always add two side by side biscuits (size 0 or 10) along the scarf, being careful not to let the biscuit poke through the leg. This helps the joint carry the sitters weight and stops the joint sliding when clamping. Try to match the growth rings of the new part to the legs, it looks better but only you will notice.
There could be a problem doing this as the stretchers are quite low to the floor and the rot may go further up than shows in the photo.
If the chairs have been somewhere damp the joints might be coming lose (the right seat rail in the photo looks to be opening up) It might be worth knocking the rear seat and stretcher rails apart to get the back section off to make it easier to work on the legs.
If it's not possible to do a scarf joint due to the stretchers you might have to add a block to the tip. This is not easy but can work and is the way I would do it on turned legs. Cut back to sound wood and get an absolute 90 degree clean surface. Make a drill guide by making a hardwood piece the same size as the leg and about 40 to 50 mm long. On a pillar drill make a 12 or 15 mm centred hole through the guide piece. Glue 4 or 6 mm ply on the guide sides with about 75 mm extensions to position down the leg, clamp this on the leg, making sure it is tight to the leg cut surface, and drill to around 35 mm depth on the leg. Make a 2 or 3 mm oversize blank for the tip and turn on a lathe a pin the right size for the hole, leaving the rest square. Aim for a smooth fit, not slack but not too tight. If there is enough room I sometimes add 6 mm dowels towards the corners of the new part. On the pillar drill make four 6 mm holes near the corners but not too close. Again check the growth rings on the leg and new piece, mark the position you pick on the parts. In the 6 mm holes put dowel points in the new piece and push and tap on the end of the leg. You should then see four indentations on the leg where you can drill 6 mm holes with a lip and spur drill. This isn't easy to get spot on so you may have to pare down the dowels to 5.5 mm. The dowels only need to be about 30 mm long. Glue and clamp then pare down the surface. If the back legs curve you will need to make a block to clamp along the leg to get an accurate clamp orientation.
Whatever way you do it it has to be done very carefully and accurate. Get it right first time as there's no second go.
I've done this type of repair hundreds of times and would go with the scarf joint Inspector recommends but I always add two side by side biscuits (size 0 or 10) along the scarf, being careful not to let the biscuit poke through the leg. This helps the joint carry the sitters weight and stops the joint sliding when clamping. Try to match the growth rings of the new part to the legs, it looks better but only you will notice.
There could be a problem doing this as the stretchers are quite low to the floor and the rot may go further up than shows in the photo.
If the chairs have been somewhere damp the joints might be coming lose (the right seat rail in the photo looks to be opening up) It might be worth knocking the rear seat and stretcher rails apart to get the back section off to make it easier to work on the legs.
If it's not possible to do a scarf joint due to the stretchers you might have to add a block to the tip. This is not easy but can work and is the way I would do it on turned legs. Cut back to sound wood and get an absolute 90 degree clean surface. Make a drill guide by making a hardwood piece the same size as the leg and about 40 to 50 mm long. On a pillar drill make a 12 or 15 mm centred hole through the guide piece. Glue 4 or 6 mm ply on the guide sides with about 75 mm extensions to position down the leg, clamp this on the leg, making sure it is tight to the leg cut surface, and drill to around 35 mm depth on the leg. Make a 2 or 3 mm oversize blank for the tip and turn on a lathe a pin the right size for the hole, leaving the rest square. Aim for a smooth fit, not slack but not too tight. If there is enough room I sometimes add 6 mm dowels towards the corners of the new part. On the pillar drill make four 6 mm holes near the corners but not too close. Again check the growth rings on the leg and new piece, mark the position you pick on the parts. In the 6 mm holes put dowel points in the new piece and push and tap on the end of the leg. You should then see four indentations on the leg where you can drill 6 mm holes with a lip and spur drill. This isn't easy to get spot on so you may have to pare down the dowels to 5.5 mm. The dowels only need to be about 30 mm long. Glue and clamp then pare down the surface. If the back legs curve you will need to make a block to clamp along the leg to get an accurate clamp orientation.
Whatever way you do it it has to be done very carefully and accurate. Get it right first time as there's no second go.
Thank you, everyone, for your ideas. That's given me something to work with. I'll let you know how I get on 
sawtooth-9
Established Member
I would cut back the leg at least 3 inches, possibly 4 inches.
If you are worried about the strength of a dowel - I use brass rod as a dowel, rough the brass rod with a coarse file and set in epoxy glue. This system will beat any scarf joint and is much easier to do
If you are worried about the strength of a dowel - I use brass rod as a dowel, rough the brass rod with a coarse file and set in epoxy glue. This system will beat any scarf joint and is much easier to do
