I'm working on a project for the kids that involves joining two 2x4's at a right angle using a mortise and tenon joint with a Narex 1/2" mortise chisel. However, I'm having a tough time because the construction lumber is quite soft. The walls of the mortise are getting crushed and they're looking uneven. When I try to remove the waste, it's tearing instead of chipping out cleanly. I've successfully chopped smaller 1/4" mortises in hardwoods without issue, and I've done larger 1.5" mortises by drilling out the waste first. But this half-inch size is proving challenging. I attempted drilling, but it's tricky to stay on the lines since I only have about 1/16" wiggle room, and I can't space them too closely without the drill bit falling into adjacent holes. I understand that my chisel needs to be sharp since I'm dealing with endgrain softwood, and I plan on sharpening it with high-grit water stones, but I worry about it staying sharp after some heavy hammering. Any tips would be greatly appreciated!
4 Answers
If this is for a kids' playset, it's fine to be a bit rough with those mortises. Just finish it up and don't stress about making it perfect. Trust me, I built a princess castle bunk bed for my kid years ago and it could have been perfect, but sometimes good enough is really all you need!
If you have a spare 1/2" chisel, consider sharpening it to a sharper angle for those softwoods. And maybe get a small fan going so you don’t get all sweaty during the process!
That construction-grade pine is not the best. You might want to try a lap joint with some screws instead.
Honestly, the joint doesn’t have to look perfect to function well. Just make sure it’s secure!