I've been watching a lot of woodworking videos, and I keep seeing folks use cauls with a curve or angle when gluing up panels. I'm curious how important that is! I don't have a bandsaw, just a table saw, jointer, and planer. I'm working on a project where I need to glue up some small panels (around 10 inches or 25 cm wide) to make the sides of a box. I'm wondering if I could just use flat pieces of scrap wood instead, clamping not just the ends but also the middle. I'll be running the panels through the planer afterwards, so I'm thinking that should keep everything aligned. Would that work, or should I go for the curved cauls?
3 Answers
While a curved caul helps distribute pressure better and can allow you to use fewer clamps, it’s definitely not mandatory for a small panel like yours. If you decide to make curvy cauls, just keep the curve subtle. Your jointer should handle that pretty well—just gradually work your way up in passes, flipping it as needed. But honestly, don't stress it for this project; flat cauls should work great!
I used to do it the same way, and it worked just fine for regular panels. Sometimes a slight curve can offer benefits, but for a straightforward glue-up like yours, flat pieces of scrap wrapped in plastic and clamped down should really keep everything aligned. Just make sure your clamps are well-placed, and you'll be all set.
One straightforward approach is to take a 2x4, get it cut to size on your table saw for some nice parallel edges, and wrap it in packing tape to keep the glue from sticking. This way, you can use it as a caul without needing any curve! Just clamp it down in the middle and at the ends, and you should be good for your 10-inch panels. You don’t really need the curve for smaller glue-ups like this.
Totally! Curved cauls are more for when you need even pressure across larger boards, but for your project, flat scrap will do just fine.