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Main Boards => The Bowyer's Bench => Topic started by: K. Mogensen on May 19, 2018, 12:48:53 AM

Title: Riser Delam
Post by: K. Mogensen on May 19, 2018, 12:48:53 AM
Would some 420 fix this? Drew it back and heard a tick. Looked the bow over and found the limb material and fade are delaminated from the riser material. It opens up when strung and drawn.

Title: Re: Riser Delam
Post by: Shredd on May 19, 2018, 08:50:46 AM
  IMO, the only way to save that is to work some superglue gel or ea-40 in the crack as far as you can get it, clamp it tight until the glue cures then take some cotton string saturated with epoxy and wrap the damaged area...  When you wrap it start in the window area and work your way out so that the string wants to stay together...
Title: Re: Riser Delam
Post by: Pat B on May 19, 2018, 10:09:27 AM
I'm not a glass bow officianato (sp) but I'd use a thin glue so it reaches as deeply as possible. Warmed epoxy or thin super glue perhaps. I don't think cotton wrap would work because even saturated with epoxy it would stretch. Maybe one of the strong, no stretch man made string materials would work.
Unfortunately the area that delaminated has the most stress of anywhere on a bow. Whether it will work or not is another question.
Title: Re: Riser Delam
Post by: Shredd on May 19, 2018, 10:52:38 AM
  Trust me...  Wrapping the whole area with epoxy saturated cotton cord will be like concrete and you could drive your truck over it... You want to use something about the thickness of kite string...  What I like about using cotton is that the epoxy saturates into the fiber and just not around it... It makes for one good solid unit...
  You could use a man-made fiber and go with a lot smaller string... But you risk the chance of the epoxy wanting to separate and delam from the fibers...  For example look at some of your old fishing rods where the coating (possibly epoxy) came loose from around the wraps that hold on the guides...  The fibers and the epoxy (coating) were not compatible...  That will never happen with cotton...
Title: Re: Riser Delam
Post by: Horsey on May 19, 2018, 11:08:21 AM
I have experience fixing such a separation.  I would cut two pieces of wood the width of the bow and shape the pieces to fit on each side.  These will be used as a mini-form for clamping.  String the bow to open up the crack and pour the Locktite 420 or other really thin super glue into the joint.  Use plenty of glue so that it completely contacts the failed area and runs out the other side.  Wrap the riser section with plastic wrap and unstring the bow.  Use c-clamps and the "mini-form" and clamp the section tightly.  Allow to cure for 24 hours.  Remove the clamps, form and plastic wrap.  You will have a significant dried super glue mess.  Sand off all the super glue.  I use 220 grit emery paper followed by 320 grit.  You will need to refinish the area.  This is the only type of repair method I would feel comfortable with if you want to preserve the strength and beauty of the bow.