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My 2015 bow

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Marc St Louis:
I can't say I believe that a high crown can pull a bow back into shape.  It's more likely that a flat back would do that since there would be more wood on the back working to do so.  No I think that a high crown takes some stress off the belly by making the back work harder thereby allowing the belly wood to take less set.  I'm convinced that a balance between tension forces and compression forces will give optimum performance.  Elm for instance is much stronger in tension than it is in compression and that's why it does so well when heat-treated.  The increased compression strength it gets when heat-treated makes the bow work harder in tension giving the wood a better balance.

sleek:
^ What he said. I would add to that but id only be parroting the TBB without any original thoughts, though I do agree.

Matthias Wiltschko:
Steve

You wrote that the bow did not reach the intended 50#. Do you think it would be a wise idea to heat treat the working section of the bow into a little bit of reflex, only 1/4", to reduce the set and increase the draw weight? Of course it would not reach the 50# but give you some fps more. Or would then the bow be to unstable for save stringing and shooting?

I was also wondering if you heat treated the recurves to a high degree to increase stiffness.

Matthias

Badger:
  The bow underwent extensive heat treating several times durring the building and tillering process. I cut the bow down to 57" NN to gain weight but after retillering wound right back up at 35# but with a better tiller. Performance is still very good but it lost quite a bit of stored energy at the shorter length.

Badger:
  I was fortunate that the gentleman who supplied me the first stave sent me the sister stve which was almost identical so in effect I was able to get a rematch.
I went a little less aggressive on this one. Slightly shorter riser, a little more working limb and less reflex. I charted the draw curve when the bow was fresh and immediately after charted it agin so I could see the difference due to set. The bow came in at 51.8#@27"  so hopefully will settle in at 50# after sanding and break in. Very happy with it so far, a little handshock but tips have not been reduced yet. Will try and test when finished.

8"            12.4#       7.8#
9"            17.4         12.2
10"          20.2         15.2
11"          23.2          18.0
12"          25.6         20.6
13"          27.8         22.8
14"         29.2          24.4
15"         31.0          26.2
16"         33.0          28.0
17"         34.4          30.2
18"         36.4          32.6
19"         38.0          34.0
20"         39.6          35.8
21"         41.0          38.0
22"         42.5          40.2
23"         44.8          41.2
24"         46.2          43.8
25"         47.6          46.0
26"         49.8          48.2
27"                          50.2
28"                          51.8

  The reading on th right is freshly drawn bow, excersised at each point, the left is the second reading. You can see where the breakdown first starts to take place at 17". This is where the spread between the two sides starts to narrow. Just based on the stored energy and typical efficiency the bow should hit about 190 fps which is faster than any self bow I have ever built. I believe Mark St louis has crossed that bridge allready.

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