Author Topic: Best way to pull out reflex  (Read 8276 times)

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Offline DC

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Re: Best way to pull out reflex
« Reply #45 on: June 15, 2018, 05:39:09 pm »
.  I'm curious, what did the raw stave looked like before heat reflexing?

It was pretty straight as far as reflex was concerned but it had a bunch of twist and a crook in each limb. it was a bit of a pain to work because I had to remember where it used to be bent when I was trying to reflex it. While I was reflexing it I also had a wrench on it to keep the twist from coming back

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As yet unproven, my theory is that if I add reflex to a straight stave with dry heat, I'm extending the belly in a way that may allow it to take back some by set, despite the remarkable things a good toasting does to a belly.   That's still beneficial, of course, unless I then kill it during tiller.

  BUT!!  If I start with a stave that dried in to 9" of reflex or was naturally already reflexed, and pull back the middle of the bow to flat or even deflexed to arrive at a manageable an=mount of reflex, then I have COMPACTED the belly using heat.  That area should be less prone to taking set, and that's where the limbs will work most, so I'm happy.   Perhaps.
Yup and i think a natural bend is even better. PatM said a while back that a backed bow with the reflex glued in holds the reflex better because the backing is actually shorter than the belly. I think a stave with a natural bend is like that.

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DC:  "There seems to be a bit of a paradox here, if you just put in a little reflex it will pull out but if you get stupid about it, it stays." 

Hmmm....  I need to think about this.  I hadn't noticed the same thing myself, but I confess, i am scared of reflex much more than 3-4", unless I'm pairing it with some defelx near the middle.  Marc's bows look really intimidating to tiller.
There may have been a touch of frustration in that statement :) I have now rasped the back off and glued on a hard maple back. I returned the reflex/deflex to about what it was when I started. After tillering for about three hours I'm now at 40#@15" on a shortish string The picture show how it is now. It feels like a bow this time. Last time(with the natural back) it felt like a noodle

Offline bradsmith2010

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Re: Best way to pull out reflex
« Reply #46 on: June 15, 2018, 05:43:31 pm »
well ok then,, proceed,,  :D

Offline Badger

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Re: Best way to pull out reflex
« Reply #47 on: June 15, 2018, 05:44:44 pm »
      I never heard that before about the glued in back being shorter but in all honesty it is so simple yet makes so much sense. That probably is the best explanation for why the Perry reflex works.

Offline Badger

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Re: Best way to pull out reflex
« Reply #48 on: June 15, 2018, 05:46:07 pm »
  I like that profile, I imagine your limbs will be considerably thinner this time around.

Offline DC

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Re: Best way to pull out reflex
« Reply #49 on: June 15, 2018, 05:51:29 pm »
I really hadn't noticed a difference between tension and compression wood before but some people on here that know way more than me claim that there is a difference. I think either Weylin or Vinemaplebows have said they won't even use compression Vine Maple. Douglas is similar to Vine. This bow just started me thinking that they were right.

As far as sinewed deflex bows goes I just thought that sinew wants to be strained and deflexing relieves strain. That's where that was coming from.

Badger- I think my comment when PatM said that was,"It can't be that simple can it?"

Offline Badger

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Re: Best way to pull out reflex
« Reply #50 on: June 15, 2018, 05:53:17 pm »
  Deflexing does relieve strain but that design of yours has plenty of strain and is an excellent candidate for sinew.

Offline DC

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Re: Best way to pull out reflex
« Reply #51 on: June 15, 2018, 05:56:21 pm »
  I like that profile, I imagine your limbs will be considerably thinner this time around.
Yeah, I just hope I don't scrape off all the heat treated wood. One of the things I don't like about backed bows is that you're very limited as to how much heat you can hit them with.

Offline Springbuck

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Re: Best way to pull out reflex
« Reply #52 on: June 15, 2018, 08:09:03 pm »
"Last time(with the natural back) it felt like a noodle."

That's very interesting.  Got me wondering if there is a logical/physical limit to reflexing due to the back not holding the tension (starting off compressed), rather than belly strain, instability, or any of the other things I'm usually worried about re: excessive reflex. 

I have had great luck with some bows that dried into lots of reflex, where I took some back with heat and left a just a few inches. 

Good stuff guys.

Offline DC

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Re: Best way to pull out reflex
« Reply #53 on: June 15, 2018, 08:27:42 pm »
I think the next thing to try is kerfing the whole bow. Very neatly and carefully saw of the back. Smooth it out a bit and glue it back on with some reflex. It would have to be a pretty good stave without to many dips or lumps.

Offline DC

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Re: Best way to pull out reflex
« Reply #54 on: June 20, 2018, 12:27:05 pm »
OK I finished this off. I backed it with Hard Maple but tried to leave everything else the same. It started out with 3" of reflex and by the time I was finished it had taken 4" of set. It was very close in appearance and performance to the natural Doug Maple back. I did see 183 fps @ 10gpp but after finishing and shooting a bit that dropped to 176-177. I'm thinking that a Doug Maple belly has to be wider than 1 1/4". Maybe 1 3/4" next time. It ain't yew but it's a good wood. :)

Offline Badger

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Re: Best way to pull out reflex
« Reply #55 on: June 20, 2018, 12:38:03 pm »
   I don't think Doug maple is even considered a bow wood. I have made a lot of self bows from it but never a laminated. I usually go about 2 1/4" on the self bows for 50#. Do you know the mass weight of this bow. Not bad performance but this design should be hitting over 182 as it did on the one shot.

Offline DC

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Re: Best way to pull out reflex
« Reply #56 on: June 20, 2018, 12:44:17 pm »
420 grams no string. I was happy with the 183 but it just started diving.