Enlarging a Pattern

I know you have seen the occasional woodworking plan with a grid overlaid on the curvy parts and the publisher expects you to be able to enlarge that for your own project. There are a lot of ways to do this with the easiest probably being taking a trip to Kinkos to blow up the image until the dimension are right. For smaller pieces I like to just lay out an actual size grid and transpose the drawing myself.

I am creating some templates for ball & claw feet as well as some trim molding for the chest of drawers I will be building next as part of The Wood Whisperer Guild summer build. I thought I would bring you all along with this process since I haven’t really found much published on it and I believe this is a skill all woodworkers should have.

Let me first say that you need not have a set of plans with a grid overlaid although that is helpful and pretty commonly available. If you only have a photograph you can add your own grid and calculate your dimensions using some known quantities. This is probably a topic for it’s own post but I just wanted to put it out there as a possibility.

In this specific case I knew I was dealing with a 1/2″ grid so I laid out a 1/2″ grid on a piece of stiff cardboard. I normally would use something like hardboard or thin ply but this is what I had on hand and it is really heavy cardboard.

Now I begin looking at the drawing and marking dots on my grid where the drawing intersect the grid. You don’t need to get hyper accurate here and I tend break each grid square down into quarters and mark the dot at the quarter or halfway point. Pay particular attention to your place on the grid and make sure you follow the drawing. By the end of this exercise you have something like this.

All that is left to do is connect the dots. I did this with a Sharpie marker so it would show up on camera better but I sketched in the lines with pencil first and shaped the curves to my liking. This is the point where you can add your own character to the design or focus on getting the reproduction just right.

Now I just need to cut out the pattern, refine it to the curve and I’m set to start shaping my blanks.