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Scarf joint question
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Scarf joint question
I am about to make the wing spars for the Charlesworth K-18, 4 metre. I need to scarf join the spruce spars, what is the recommended length of the joint? 5 x width? More?
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Re: Scarf joint question
Harry
A structural scarf joint should be 15 x the thickness of the pieces being joined.
AEB
A structural scarf joint should be 15 x the thickness of the pieces being joined.
AEB
AEB = Aeronautical Energiser Bunny (with thanks to CW)
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Re: Scarf joint question
Thanks John,
the spars are 10mm wide x 3 mm thick, so the joint should be 15 x 3?
the spars are 10mm wide x 3 mm thick, so the joint should be 15 x 3?
- RobbieB
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Re: Scarf joint question
.................and Harry, make sure they are perfect. Check both down their length and across the width with your straight edge and clamp really tight.
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Re: Scarf joint question
Harry , what glue are you using on such a critical joint ?
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Re: Scarf joint question
Yes Harry. 45mm.harry curzon wrote: ↑23 May 2019, 09:16 Thanks John,
the spars are 10mm wide x 3 mm thick, so the joint should be 15 x 3?
AEB
AEB = Aeronautical Energiser Bunny (with thanks to CW)
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Re: Scarf joint question
Thanks John
- VinceC
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Re: Scarf joint question
Vince, the splice angle recommended from the table is 15 to 1 for ply and 20 to 1 for wood. This is what we were working on with K13s and K8s. What I can't understand is the diagram below ? Surely the joint is stronger in bending load than shear load ? Regards John.
- chris williams
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Re: Scarf joint question
What about the scaling factor...? Surely, a 1/4 scale spar would only need 1/4 of those dimensions?