Updated: Jan 25
Italian Postmodern Tripod Black Lacquered Dining Chair, Repair. The two dovetail tenons damaged a large section of plywood as they broke loose of their mortises. This section of plywood has been replaced with a solid wood (poplar) patch. Plywood is weakest from this angle, so the patch was done to give the two dovetail tenons a better material to mount into from this particular angle. The chair has been repaired and reassembled the same way the manufacturer had designed it, with a few updates to increase its durability.
Since this chair is a part of a set, the client decided to have it repaired.
Instead of patching the missing layers of plywood, I decided to remove the damaged section. First, I used my track saw to make two parallel angled cuts, about a half-inch deep. Then set the track saw angle back to 90 degrees. I then began the tedious process of kerfing out the rest of the damaged plywood one cut at a time, shifting the saw over 1/8 inch until I removed all the material between the first two parallel cuts.
Kerfing works well to remove material in a straight line and at a specific depth, but it does not leave a smooth surface behind. So I threw together a simple router sled big enough to span the gap. If set up correctly, the router and sled will precisely level out the rough surface left by the repeated cuts made with the track saw. I then planed down a piece of poplar to the same depth as the patch and cut both ends with a matching angle. Before gluing the patch into place, I roughly cut out the approximate mortices that will need to be there to reattach the rest of the chair. Doing this eliminated a lot of measuring later in the project when trying to fit tenons back into place.
After hand planing the excess outer edges, I sanded it down to its final profile using sandpaper wrapped around a block of wood to maintain a consistent edge. Fitting the tenons back into the mortises was awkward, to say the least. The original joint was poorly done, the tenons never fit correctly, and there were remnants of wood glue and shims shoved onto the joint to fill in the gaps. I did my best to make a tighter joint, and it was good enough to hold everything in place, but I wasn't satisfied enough with it to just use wood glue to join the chair back together. After some research, I decided to use PC-7 Epoxy Adhesive Paste to join the chair back together. I usually avoid epoxies as much as possible, but this product worked well in this situation. I put a fair amount of the epoxy into the tenons and then slowly worked the tenons into place. The thick epoxy paste filled in the awkward joint, and after clamping, it resulted in a strong joint I was satisfied with.
To help create a seamless transition between the chair and the new patch, I used Goodfilla Wood and Grain Filler. This filler can work as a leveling paste under paint to hide small seams and imperfections.
On the backside of the chair, there were two very noticeable cracks in the lacquer, So I sanded these down and then leveled the surface out using the previous method.
I used Bulls Eye 1-2-3® Water-Base Spray Primer to seal in the repairs. Then sprayed on two coats of Premium Decor Gloss Lacquer Finish, Black. Then finished with two coats of Premium Decor Gloss Lacquer Finish, Clear.
Disclaimer/Reminders/Products & Tools Mentioned.
These tools are used for cutting, carving, planing, sanding, and routing wood and other materials with ease, and they will do the same to your body if you don't follow the manufacturer's instructions. Your reflexes aren't fast enough; by the time you realize what's going to happen, your finger is already gone. Read tool instructions and product labels, wear eye protection, gloves, and ear protection. Nothing you're working with can be eaten, inhaled, or inserted into your eyes in any way, and always work in a well-ventilated area. Whether it is a solvent, paint, spray, filler, lubricant, oil, grease, finish, assume it's flammable. Sawdust is just wood with more air, so it is extremely flammable.
To prime or not to prime? PRIME! No, all in one "paint & primer" does not count as priming.
Expensive chisels don't sharpen themselves, so buy the cheap ones and learn how to sharpen them.
Festool - Plunge Cut Track Saw TS 75 EQ-F-Plus
PC-7 Epoxy Adhesive Paste
Goodfilla Wood and Grain Filler
Bulls Eye 1-2-3® Water-Base Spray Primer
Premium Decor Gloss Lacquer Finish, Black.
Premium Decor Gloss Lacquer Finish, Clear.