Question

Dear Mitch,

My husband and I are hanging small pictures in our new home on a wall next to the fireplace. The wall is not quite three feet wide, but we're having trouble getting the pictures centered the way we'd like. 

The trouble is we have a yardstick and a tape measure and just about everything else we could need, but even when we want to make sure we're lining things up right, we just seem to be a little to the left or a little to the right, but never perfect.  We can do the math, of course, and just cut the wall's dimension in half, but both the yardstick and the tape measure slide around and there's no way to assure that it's parallel with the floor or the ceiling. We tried using one of those t-squares, but it too seemed to slide out of position. My idea was to cut a strip of paper the exact same width the wall, and then fold it in half and put a hole in the middle of that fold with a hole puncher.  But again it didn't seem to land the little pictures in the center.  Any ideas that won't require us to mark up the whole wall?

Sincerely, 

K. Cole

Wilmington, DE.

Answer

Dear Ms. K. Cole, 

Your idea with the folded paper sounds pretty good to me, especially if the paper you use is wide enough to use its side to assure that things are reasonably close to square.

But, unless I am mistaking the part that you're finding most challenging, you need to find a way to check that you are holding your tape measure or yardstick at a right angle to the wall's edge ("perpendicular") or all your centering will not go well. 

Here's a way I very recently did a similar procedure in my new home, and I'm satisfied with the results. Combining the well-known geometric principle that the shortest distance between two points is a straight line with the well-known idea that if one of those two points is the vertex of a circle, and you rotate a radius (yardstick) from it, you will end up forming an arch of the set of all points the same difference from that vertex, and the one which lands on the wall's other edge is the second point worth dotting with a pencil (The first is, of course, the one from which you pivoted the yardstick to form the semicircle; dot that point as well.)

With a minute's practice you will note that any other point of the yardstick that hits the edge of the wall will give a larger measurement than the radii of the arch, and therefore not be the correct endpoint to form the perpendicular line segment you need.  NOW, it should be relatively easy to use your same yardstick or tape measure, hold it along the line segment that connects your two dots, and put a third dot on the wall above the measurement of 'halfway-ness'.  So, for example, if the wall is forty-two inches wide, twenty-one inches will be the 'dot spot'.  Place the nail or hook there and see how it looks.

Then, if you really are hanging a sizeable series if pictures along the same center line of the wall, you just have to do this swinging of the yardstick once more to get one other midpoint (either higher or lower than the first).  Then connect those two midpoints with a light line or a string with scotch tape or thumbtacks and you have your guide line for all points equidistant from both sides of the narrow wall.

Good luck in your new home!

Hope this helps,

Mitch