{"id":15260,"date":"2017-06-12T18:41:10","date_gmt":"2017-06-12T22:41:10","guid":{"rendered":"http:\/\/chcollins.com\/100Billion\/?p=15260"},"modified":"2024-12-03T11:04:49","modified_gmt":"2024-12-03T16:04:49","slug":"hang-it-with-two-hooks-calculator","status":"publish","type":"post","link":"https:\/\/chcollins.com\/100Billion\/2017\/06\/hang-it-with-two-hooks-calculator\/","title":{"rendered":"The “Hang It with Two Hooks” Calculator"},"content":{"rendered":"

Asked and Answered 3.2<\/em><\/strong><\/h4>\n

\"Click<\/a>Two years ago, I posted an article here called Why Frames Tilt Forward<\/a><\/em>, explaining why the top of a picture frame tilts away from the wall and what one should and should not do to address this.<\/p>\n

The mistake that most people make (and a remedy that even some frame shops prescribe) is to fasten the wire tightly across the frame so that there is almost no slack in it.\u00a0 But as I pointed out in my article, this can put considerable strain on the wire and the frame when the picture is hung.<\/p>\n

If you don’t believe that a professional framer would make such a mistake, let me share a little story.\u00a0 We recently took a favorite picture of ours to a local frame shop for reframing so that it would better suit our d\u00e9<\/span>cor.\u00a0 It was a large frame, about 46″ wide and 34″ high.\u00a0 When we picked up our frame, I noticed how taut the wire was, and I mentioned this fact to the owner.\u00a0 I also told her about my blog post on this topic.\u00a0 She seemed disinterested.<\/p>\n

Rather than argue with her, I decided I would rewire it when I got home.\u00a0 As I was carrying the frame into our bedroom by its wire (the only practical way to carry such a large piece), the wire snapped and the corner of the frame hit the floor.\u00a0 Luckily, I was carrying it only eight inches or so above the floor and, luckily, the floor was carpeted; otherwise, the frame or the floor or both would have been damaged.\u00a0\u00a0 Rest assured, I was not carrying the frame in such a way that it bounced around and tested the wire.<\/p>\n

I rewired the frame with my own hardware, my own wire and according to my own rules, and I am confident that it will now not fall, bend or break.<\/p>\n

On our next visit to the framer, I told this story to the owner, who remained unconcerned. Her response was that a frame should not be carried by its wire.\u00a0 Apparently, she was not\u00a0 familiar with the concept of a safety factor.\u00a0 I thought her excuse was as flimsy as her wire.<\/p>\n

Clearly, this frame shop is winging it.\u00a0 They are content to string a wire across the frame and call it a day.\u00a0 They are not mindful of physics — and they will not have a second chance to demonstrate this to me.<\/p>\n

So… how do you know whether your<\/em> frame shop is using their heads?<\/p>\n

\u2022 \u2022 \u2022 \u2022 <\/em><\/p>\n

But enough of cautionary tales.\u00a0 In Why Frames Tilt Forward<\/a><\/em>, I suggested that one way to achieve a low-tilt and low-tension installation is to use two wall hooks and 45\u00b0 wire angles\u00a0 (see figure below<\/a>).\u00a0 My instructions, however, were not so easy to follow — I know, because I tried to follow them myself.\u00a0 The main difficulty was figuring out exactly how much wire to cut, something my instructions had not spelled out.\"Two<\/a><\/p>\n

This is an ideal application for an online calculator — no fancy math, just basic geometry.\u00a0 So, to help my readers, I have programmed my formulas into the wiring calculator below.\u00a0 The user enters the outside dimensions of the frame (W<\/span><\/strong> and H<\/span><\/strong>), the size and position of the D-rings fastened to the frame (D<\/span><\/strong> and V<\/span><\/strong>), and the desired distance from the top of the frame to the bottom of the wall hook (Z<\/span><\/strong>).\u00a0 The calculator returns the vertical position of the D-rings (Y<\/span><\/strong>), the spacing of the wall hooks (X<\/span><\/strong>), and the length of wire to cut, which includes three inches at each end for making knots.\u00a0 To make things easier, some default values are suggested and results are rounded to the eighth-of-an-inch.<\/p>\n

Notice that my illustration suggests the use of D-rings as well as double-nail wall hooks.\u00a0 D-rings are preferable to screw-eyes because D-rings lay flat against the back of the frame, reducing the propensity for the frame to tilt forward.\u00a0\u00a0 And the wide base of double-nail wall hooks can help distribute the lateral forces associated with a two-hook installation.\u00a0 More on this in the final post of this series, The Physics of Hanging Pictures<\/a><\/em>.<\/p>\n

In my low-tilt, low-tension scheme, the D-rings are placed one-fifth of the frame height below the top, for frames that are 30 inches tall or less.\u00a0 (For frames taller than 30 inches, the calculator transitions to the one-sixth rule.)\u00a0 The wall hook spacing and the wire length follow directly from this.\u00a0<\/p>\n

However, if the calculated wall hook spacing is less than one-third of the D-ring spacing, the calculator suggests values for a one-hook installation instead.\u00a0 In the one-hook case, the wire angle varies with frame height, but the angle will be at least 33\u00b0 above horizontal.<\/p>\n

One final note:\u00a0 If you are not using D-rings, then set D<\/span><\/strong> equal to 0<\/span> and set V<\/span><\/strong> equal to the horizontal distance from the edge of the frame to the wire attachment point.\u00a0 Y<\/span><\/strong> will be the distance from the top of the frame to the wire attachment point.<\/p>\n

Click CALCULATE after editing your entries to view the installation instructions.<\/span><\/p>\n\n\n\n