You can’t play Sea of Thieves with this type of “X Box,” but you can use it in your sewing projects to secure all types of straps and narrow panels. It’s simply a stitched box with an “X” through the middle. This stitching pattern provides a high level of strength and stability, and when done with precision, it also adds a pretty detail. Try it with a contrasting thread color for extra emphasis. Here at Sew4Home, we use the stitch often to hold an apron strap in place or to secure a handle to a bag. The function of an X Box in home sewing projects is to both achieve a tight bond and to look smooth and even. We show options for a classic single stitch box as well as the commercial-style double stitch box. 

You first need to determine the size of X Box you want to create, which includes how close to the edge you want the stitching. For our sample, we created a 2″ box with ¼” spacing from the sides and bottom of our prototype strap. This allowed us to use our Quarter Inch Seam foot for extra precision.

You can make your box any size you’d like, although the technique starts to lose some of its inherent stability at about 3″ tall.

You can also choose how close to the edge of the strap, or other element, you want to run your stitching. From ⅛” – ¼” is standard. Much closer, and you risk the edge of strap pulling out from the stitching. Much farther away, and you’ll create a “lip” of fabric that can flip up or otherwise look bulky and unprofessional.

Gather your materials. We most often use a standard all-purpose thread and universal needle for this technique, however, in situations where your bond needs extra strength, consider a 30 wt cotton or a nylon upholstery thread with a 16 needle. This would be a good choice when working with nylon webbing on a heavyweight canvas substrate.

A single stitch box with hand-tied thread tails to secure

1. Using a clear ruler and a fabric pen or pencil, measure for the height of the box plus your seam spacing. For our sample we used a 2″ box plus a ¼” seam spacing. We measured 2¼” up from the end of the strap and drew a horizontal line.
   
2. In addition to this main line, you may want to make an additional crosshair starting point in one bottom corner. Many people simply use their presser foot and/or the markings on their needle plate to determine this, but you can also use your seam spacing amount (¼” in our sample) to measure from the bottom up and the side in to create a crosshair for your starting point. 
3. If you are just starting out, you can certainly draw out the entire box and the “X” with your fabric pen or pencil, giving yourself a full set of guidelines.
4. Following your project’s instructions, place your strap into position as directed, such as centered over a seam or parallel with a pocket.
5. Pin the strap onto the base fabric. You don’t need a lot of pins, one or two at the bottom edge and one or two at the horizontal marked line are plenty.
   
6. Thread your machine with either matching or contrasting thread as indicated for your project. We used contrasting thread in two different colors (brown in the top and pink in the bobbin) so you could easily tell which thread was which when we hand-tied the tails. 
7. Depending on your fabric weights and the finished look you wish to achieve, you may want to consider lengthening your stitch. We like the look of a lengthened stitch for most topstitching. 
8. Starting in a bottom corner, drop your needle at the exact point of the corner. As mentioned above, use your presser foot and needle plate guidelines to determine the starting point or your own marked crosshair. Make sure your thread tails are 4-5″ long.
   
9. Do not lock your stitch to start. Simply start stitching from the bottom corner, continuing up one side. Stop, with the needle in the down position, at the drawn horizontal line.
   
10. Lift up the presser foot and pivot 90˚.
    
11. Stitch across to form the top of the box, following your drawn line and removing the pins as you go. Stop, with the needle in the down position, at your determined stitch width from the opposite side – ¼” from the opposite side in our sample.
    
12. Lift up the presser foot again, and again pivot 90˚.
    
13. Stitch down the opposite side, stopping with the needle in the down position in the bottom corner. 
14. Lift up the presser foot again, and again pivot 90˚.
    
15. Stitch across the bottom of the box, completing the box and arriving back at the exact corner point where you started. Stop at this original corner with the needle in the down position.
16. Lift up the presser foot, and pivot 45˚ so the presser foot is now aligned on the diagonal.
    
17. Stitch across the box on the diagonal, stopping at the opposite corner. Do not lock your stitch.
    
18. Remove the project from the machine, cut the tails to a long length, about 4-5″.
19. Replace the project under the presser foot, dropping your needle in at the opposite corner and positioning the foot to create the intersecting diagonal line. Make sure your starting thread tails are long – again about 4-5″ is good.
    
20. Stitch across the box on the diagonal, stopping at the opposite corner. Do not lock your stitch.
    
21. Remove the project from the machine, again cut the tails to a 4-5″ length.
22. You now have a finished box with four sets of long thread tails – one pair at each corner.
    
23. To secure these starting and stopping points, you will tie off the tails at the back and trim away the excess thread.
24. Flip over the project so you are looking at the back of the X Box. Remember, we used two colors of thread so you could easily see the two strands: brown in the top (for the front) and pink in the bobbin (for the back).
25. Pull on the back thread tail until you see a front thread loop pop through. We are pulling on the pink thread tail, looking for a brown loop.
    
26. Insert a pin into the front loop (the brown loop in our sample) and pull that thread all the way through to the back side.
    
27. Tie together the tails with two or three simple knots, pulling the thread tight against the fabric.
    
28. Trim away the excess thread close to the knot.
    
29. Repeat for the other sets of thread tails. Flip back over to admire your pretty X Box.
    

A reinforced double stitch box

1. A reinforced X Box is sewn in a continuous line, creating double stitching along the top and bottom. 
2. As mentioned above, this is an option for additional strength so you may want to consider switching to a heavier thread and a stronger needle.
3. Measuring and preparing for the box is done in the same manner as described above.
4. With your strap in position, start in the upper left corner. Because this upper line of stitching will be doubled, you do not need to lock the seam to start. Instead, drop the needle at the start point and shorten the stitch length to 0.5mm. Take three to four stitches, then return the stitch to the desired length.
   
5. Sew across the top. Stop in the opposite upper corner. With the needle in the down position, pivot 90˚. Stitch down the first side, pivot at the bottom corner, then stitch across the bottom.
   
6. Pivot and stitch up the second side, ending at the upper left corner where you started. As above, always stop with your needle in the down position prior to raising the presser foot to pivot.
7. With the outer perimeter of the box stitched, pivot 45˚ so you are aligned on the diagonal and stitch diagonally through the box to the bottom right corner.
   
8. Pivot so your foot is directly aligned with the previous stitching.
   
9. Stitch across the bottom of the box, directly over the previous stitching. At the opposite bottom corner, again pivot 45˚ so you are aligned to stitch on the diagonal.
   
10. Sew diagonally through the box to the upper right corner. Pivot and sew across the top of the box – as you did along the bottom, you are again sewing right on top of the previous line of stitching. End in the same upper left corner where you started.
    
11. Lock the stitch as described below or tie-off your seam as described above.
    
12. The illustration below shows the eight lines that make up a reinforced X Box and the order and direction in which they are sewn. Take note that stitches 1 and 8 as well as stitches 3 and 6 are sewn one on top of the other. In the illustration below they are spaced apart so you can clearly see the sewing direction, but as described above with the photos, both the top and bottom seams are doubled.
    

Using a lock stitch to secure

1. The hand-tied method shown above gives you the cleanest finished box, but it is more time consuming. 
2. We do not recommend using a traditional backstitch/back tack to secure your stitching; it will look too messy. But, if your machine has a lock stitch function, this is another option. All the steps are the same as above, simply adding a lock stitch at the very beginning, and ending with a lock stitch at the completion of the first diagonal line. 
3. Then start and end the final diagonal line with a lock stitch.
   
4. Trim away the thread tails as close as possible to the stitching on both the front and back.
   
5. In the photo below, the hand-tied box is on the right and the lock-stitched box is on the left. You can see the heavier thread coverage at the corners of the lock-stitched box. This means the lock-stitch method would be best for a box stitched with matching rather than contrasting thread so these heavier corners are less visible.