Stretcher Bars Online
  • Home
  • Buy
    • Canvas Stretcher Bars >
      • Wunderbars
      • Casbar
      • Traditional Stretcher Bars
      • Custom Made Stretcher Bars
      • Ready Made Stretchers
      • Stretcher Bar Shapes
    • Frames and Display >
      • Canvas Framing
      • Wall Decor Panels
      • Photo Frames
      • Canvas Hangers
    • Inkjet Media >
      • Inkjet Canvas
      • Photo Inkjet Media
      • Fine Art Inkjet Media
    • Frame Packaging >
      • Postal Boxes
      • Framing Tape
      • Wrap and Protect
    • Discounted Items
    • End of Line Clearance
  • Contact
  • Bespoke and Cross
  • Delivery Info
  • About Us
  • Blog
  • Stretcher Questions
    • What is a stretcher bar
    • What are stretcher bar wedges
    • How to fold canvas corners
    • Making mirrored canvas wraps
  • Privacy Policy
  • Terms and Conditions
  • Site Map

WHAT ARE STRETCHER BAR WEDGES?

HOW DO STRETCHER BAR KEYS WORK?

What are stretcher bar wedges
TYPICAL WEDGES/KEYS
Canvas stretcher bar wedges are the small triangular wooden (or plastic) triangles inserted into the four corners of a stretcher bar frame. By tapping these into the corners using a hammer they open up the join to stretch a canvas print. These may or may not be included by the supplier dependent on where you purchase them. Generally made from plywood or plastic there can be either one or two per corner. The amount per corner can vary between canvas stretcher bar suppliers.

STRETCHER BAR WEDGE MATERIAL

Wedges/keys can take on a variety of forms dependent on the stretcher bar supplier. Most commonly the wedges will be in plastic or plywood, however beech, solid timber and oak are also used, among other woods. This generally depends on the image that's being stretched. You'll find that museums use high quality wooden wedges made from high quality timbers to complement the artwork. Wooden wedges of any sort tend to contract and expand with the stretcher frame depending on the rooms environment, reducing the likelihood of them falling out in the future. As plastic wedges do not have this trait you'll find small "lumps" in them to hold them in the corners. 

WEDGE SHAPE AND QUANTITY

how to put wedges into a stretcher bar
HOW WEDGES ARE INSERTED INTO A STRETCHER BAR
Wedges will generally be triangular in shape. However, also common, especially in plastic wedges, is having one of the sides flattened to slide across the frame when inserted. Flat sides are also usually found on "one wedge per corner" stretcher frames. There is no real difference in having one wedge in the corner, though there are some schools of thought that this may cause uneven tension across the frame. UK stretcher bar manufacturers largely use two triangular plywood wedges, whereas Baltic or Chinese purchased stretchers tend to opt for one. Here at stretcher bars online, being a UK manufacturer we use two, supplied free, plywood wedges per corner.

HOW TO USE A WEDGE/KEY

Common stretcher bars like the picture on the right have two gaps to fit the wedges. If you look inside the gap you'll notice that the hole reduces in size the further back it goes. As the wedges are tapped into the frame it pushes apart the corners thus stretching the canvas. Although most canvases will be stretched initially using stretcher pliers, wedges can be used to also stretch the canvas. Typically this will happen when the canvas becomes slacker over time. By tapping in the wedges once more re-stretches a canvas
Return to stretcher bar questions
STRETCHER BAR KEYS INSERTED IN A CANVAS BAR
HOW A KEY INSERTED IN A CANVAS BAR

contact

  • Get in touch
  • Send us an email
  • How to find us
  • Help and Support

Products

  • Available Stretchers
  • Canvas
  • Tape
  • Packaging
  • Hangers

Terms

  • Privacy Policy
  • Delivery terms
  • Refund

This website is maintained by Wunderbars Limited, trading as Stretcher Bars Online. For more information on Wunderbars, please visit www.wunderbars.com
Wunderbars Limited. Unit 9 Broadwyn Trading Estate, Waterfall Lane, Cradley Heath, West Midlands, B64 6PS. 0121 559 4476.    Company Number - 6931371
Google+
  • Home
  • Buy
    • Canvas Stretcher Bars >
      • Wunderbars
      • Casbar
      • Traditional Stretcher Bars
      • Custom Made Stretcher Bars
      • Ready Made Stretchers
      • Stretcher Bar Shapes
    • Frames and Display >
      • Canvas Framing
      • Wall Decor Panels
      • Photo Frames
      • Canvas Hangers
    • Inkjet Media >
      • Inkjet Canvas
      • Photo Inkjet Media
      • Fine Art Inkjet Media
    • Frame Packaging >
      • Postal Boxes
      • Framing Tape
      • Wrap and Protect
    • Discounted Items
    • End of Line Clearance
  • Contact
  • Bespoke and Cross
  • Delivery Info
  • About Us
  • Blog
  • Stretcher Questions
    • What is a stretcher bar
    • What are stretcher bar wedges
    • How to fold canvas corners
    • Making mirrored canvas wraps
  • Privacy Policy
  • Terms and Conditions
  • Site Map