Note: Repairing a rib of a square canopy is similar to doing a partial panel repair. The biggest difference comes when the rib is either [1] a “loaded” rib or one with support tapes for the line attachment points, or [2] a crossport is damaged and needs to be repaired and recut. In this case, the crossport area needs replacement [Figure A].


  1.1 Determine the extent of the damaged area and unpick the top and bottom seams to access the rib [Figure B]. In most cases, restitching the rib to the top and bottom panels is fairly straightforward. Because of this, opening up the seam for a good distance (18" plus either side of the proposed patch) will allow easier access and sewing.

  1.2 Pin the damaged rib to the pin board to stabilize the material for marking. Mark out the damaged portion of the panel, following the weave of the fabric [Figure C]. This will be the patch fold lines and the limits of the partial rib panel. Note that the tears of the crossports have been taped together and that the crossport has been pinned down to stabilize the fabric during the marking process.

1.3 Using the patching square, mark a parallel line .75" inside the patch fold lines and then another one .62" inside the second line [Figure D]. The inner lines will be the trim lines for the rib patch.








  2.1 Cut a piece of fabric approximately 4" wider and longer than the damaged panel area. Make sure that one of the width edges is straight and even with the weave of the fabric.

  2.2 Fold the straight edge .75" from the edge and pin in place across the damage line. Make sure the fabric is centered on the existing panel.

  2.3 Remove the pins from the crossport area and smooth the new panel fabric over the damaged panel.

  2.4 Fold the new fabric outwards at the patch fold mark and pin in place. Use the patching square to mark a line at .75" in from the fold line [Figure E].

  2.5 Trim the repair panel at the inner line [Figure F], fold under and pin in place.

  2.6 Check the tension of the two panels. They should be equal. Mark the top and bottom edges [Figure G] and the crossport location [Figure H].

  2.7 Remove the rib from the pin board. Sew the two outboard seams approximately .06" from the edge with the single needle [Figure J].

  2.8 Trim the original damaged panel to the trim lines [Figure K]. Fold the fabric under to create a French fell seam. Repeat with the opposite seam [Figure L].

  2.9 Sew the inside row to complete the seam [Figure M].

  2.10 Cut the new crossport to match the original location and shape [Figure N].

  2.11 Trim the top and bottom edges as marked [Figure O].

  2.12 Pin the top seam back onto the top panel. Sew in place with either the single needle or if available, with the double needle machine and puller [Figure P]. Repeat with the bottom seam.

  2.13 Inspect finished work [Figure Q]. 3.0


  3.1 Seam alignment should be straight.

  3.2 Check the tension of the replaced rib material.

  3.3 Make sure the seams are restitched correctly.

  3.4 Verify that the crossport is cut correctly.

  3.5 The line attachment tape must be replaced correctly with no twists in the suspension line.




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