Boo backed hickory bow based on Arvin’s design.

[Kidder]

Fantastic bow Dave! How much of the reflex was glued in vs heated in?

[simk]

Great work Dave! For sure impressive reflex like many of your bows. Sure fast. Is that amount of reflex durable, how long? Just asking because I'm usually not capable to preserve that much reflex in a wood-only bow,...I dont even try anymore  My conversion rate is low, I usually can only keep 20-30% of the glued in reflex, the more the less...  The fulldraw pic is strange...do you tilt the bow in your hand to the side? Lower limb looks way shorter than the upper one with all the bend concentrated midlimbs.... I'd love to examine that true money shot.
cheeers

[superdav95]

Great work Dave! For sure impressive reflex like many of your bows. Sure fast. Is that amount of reflex durable, how long? Just asking because I'm usually not capable to preserve that much reflex in a wood-only bow,...I dont even try anymore  My conversion rate is low, I usually can only keep 20-30% of the glued in reflex, the more the less...  The fulldraw pic is strange...do you tilt the bow in your hand to the side? Lower limb looks way shorter than the upper one with all the bend concentrated midlimbs.... I'd love to examine that true money shot.
cheeers

Thanks so much Simk!  Yes I was very impressed at how much reflex these bow maintained.  Both bows were similar in length only difference is that the one with the handle laminated sections (give away bow trade bow) was only 1.3” at widest point while this one was around 1.4” wide.  Both started as seasoned hickory staves that had a deep heat treatment bake.  I decrowned the back of both to about 1/2” thickness thereabouts on limbs.  This allowed me to keep more of the darker belly I suspect.  It was a chance that I took wondering if it would be too weak in the end but it was pretty bang on.  Good guess I suppose.  The stave blanks prior to glue up looked pretty flimsy.  I also kept my boo slats very thin.  My worry was it overpowering the hickory.  So going thin thin moved the neutral plane to a favourable spot in the limb I suspect.  I tapered the boo like you would normally do thicker at the handle section and tapered out to the tips.  Thickness at the tips were around just under a tenth of an inch.  .090.  The handle are was around .120-.130”.  On these bows I did the glue up on the blank and then tillered it.  I did a very basic floor tiller prior to decrown of back in prep for glue up.  The glue I use isn’t anything special just the ea 40 smooth on.  I do a 2:1 (2 parts A to 1part B) mix according to the mix labels on the can.  I don’t find I need to hot box the glue up either.  Don’t find it made any difference for me.  I glued in 5” reflex on these ones and amazingly they kept 4-4.5”.  I’m not sure how as I too have had issues with this maintaining that much reflex after glue ups.  These two bows are a different animal for some reason.  The only thing I can think of that I did little differently on these two was that I toasted the belly of boo strip.  I noticed that as I did this it swelled up a little to the point where I needed to Re flatten them on the belly for glue up.  My boo is also not from prepared 2” wide  slats.  Not sure if this has anything to do with it but I use large mosso poles that I get in 10 foot lengths.  I prepare my own slats.  It’s more work and I can’t see it being a thing that makes any difference but one wonders.  Obviously taking into consideration the node placement along the limbs which you already know is I think important too. 

As to the pics ya they are not great.  I am canting the bow slightly it appears.  The top limb is an inch longer but ya the bend in the pic looks weird I should try and get another one posted.  My wife was in a hurry too so I took what I could get.  As far as durability I sure hope so .  Time will tell I suppose.  The one bow has aprox 200 shots thru it and the other has around 160.  The narrower one at 27” and this one at 28”.  As a point of interest the narrower one holds slightly more reflex for some reason.  Both bow creep back to around 4-4.5” after unstringing for around 10-15mins.  Hope this clarifies some things anyway. Thanks for Looking.   Dave

[Stixnstones]

It looks fast as all get out just sittin still

[Juan Ant. Espinosa]

Ufff... nice bows all arround. Congratulations for such a fast, agresive and beautiful bow.
For sure, a video about the bamboo side dying would be fantastic.

[superdav95]

Thanks guys.  Stix.  Yes it’s a good shooter.  Juan,  I will do that and post it on this build with a short vid link.  Stay tuned. 

[superdav95]

Hey guys.  I was asked about my boo strip prepare method so figured I’d post it here on this post as it applies to this build too.  Basically what I do as can be seen in the video clip is lightly heat temper or treat the belly of the strip and very lightly heat the back a little too not so much to toast it like I do on the belly but enough to get steam escaping as can be seen.  Too much and your boo strip will be too brittle and could find yourself is a situation where something explodes.  Don’t ask how I know this!   In the video you can see I’m moving back and forth over a radiant heat source.  This is just what I’ve found works for me.  You will get a smell similar to popcorn or slightly burnt popcorn when doing this. My wife hates it!  Lol.  You may also actually hear the steam coming out of the strip.  In the pics here you can see the the belly side does swell a tiny bit so like I said before on this thread you’ll have to resurface the belly prior to glue up.  The results I think are noticeable.  Can’t say it’s just this one aspect that makes all the difference between these two bows and others I’ve done but a few things done and minor tweak’s combined I think added up to make the difference.  Time will tell on the longevity of these bows have retained this much reflex being all wood laminates but one can be hopeful and it’s the little tweaks that sometimes make the difference.  In the pics you can see that after heat treatment this little 23” test piece in the demonstration loses about 11grams of mass. From 165 grams to 154 grams. Water weight loss.   You’ll also notice that the first pic shows the slight swell on the belly.   As I mention in the video the lignins and pectins in the boo harden up much like sugars and starches do when heated.  This was discovered to improve moe and overall strength of the boo.  There is a great study that was done in china I believe that I referenced when doing my own testing for its application to bows. They were studying the benefits of heat treatment of bamboo for application in construction.    Anyway enjoy the video and thanks for following along in my builds and hair brained ideas. 



Short video…

https://photos.app.goo.gl/vxKkhpGcawgg7xXh7

[bjrogg]

Sweet bow Dave

It would be so cool to get a bunch of us to the flats with Arvin.

I’m sure it would be a great learning experience for everyone involved.

I to have been the benefactor of help from Arvin.

I have a flight bow ready almost ready to go. Need a different string and a little finish work.

I just can’t get away in September I believe?

Sure would be a hoot

Bjrogg

[superdav95]

Sweet bow Dave

It would be so cool to get a bunch of us to the flats with Arvin.

I’m sure it would be a great learning experience for everyone involved.

I to have been the benefactor of help from Arvin.

I have a flight bow ready almost ready to go. Need a different string and a little finish work.

I just can’t get away in September I believe?

Sure would be a hoot

Bjrogg

Thanks Bj.  Yes for sure.  That would be a great time.  We will have to do it one of these years.  I might be able to swing it for next year!  I’ll reach out to Arvin and see if we can plan for it and make it happen.  He’s got me getting keen on the flight stuff and all the voodoo magic that goes with it.  😎.

[superdav95]

I was able get a better full draw pic uploaded.  Hope this looks little better.  Cheers

Dave. 

[Will B]

Nice bow!…and thanks for posting the video. Very interesting. I plan to heat treat my boo on my next boo-backed bow.

[Selfbowman]

Looks good Dave!! That’s a more of a contentious reflex but I think the most important thing is get the tips forward of the back of the handle as much as possible with out set. Looks like you achieved that really good! Excellent speed from that bow ! Yes that is a contender!

[Bob Barnes]

Thanks for the video, it does a good job of explaining how to do it.  The full draw profile of that bow is awesome!   

[Muskyman]

Okay, I watched the video. Your doing that over the kitchen stove, in the house. I’m thinking my wife would tell me to buy a hot plate and get out of the house with that nonsense.
You got a good one Dave, I’d keep her if I were you. 

[superdav95]

Okay, I watched the video. Your doing that over the kitchen stove, in the house. I’m thinking my wife would tell me to buy a hot plate and get out of the house with that nonsense.
You got a good one Dave, I’d keep her if I were you.

Ya she’s a good sport for sure.  lol