BBH design ? and Build

[Stick Bender]

Hi Fellas I need some exsperience using smooth on , on another bow I'm building so I figured I would make this BBH to get it , it's going to be 68 1/2 ntn 12 in. riser so it leaves me 29 in. of working limb I'm not puting in any deflex ,more  of a hill inspired design I want to put in 6 in. of tip reflex on the form but trying to figure where to start the reflex I'm thinking about 12 in. Out of the fade keeping the reflex in the last 17 in. does that sound about right ?

[Dances with squirrels]

6" of reflex in 17" of limb sounds like a good bit, but you can do it that way if you want. You should do a dry run to be sure the pieces will take that degree of bend. If not, and I HAVE had them break on dry runs, at least you don't have everything covered in glue, and you can take your time and fix or remake the piece that broke.

It's doable, but you'll have to get the hickory close to finished thickness dimension so it will take the bend without breaking.

You have a few other options. You can heat it and bend it to shape prior to gluing it up. Or, stop short and go for less reflex if, on your dry run, it's too hard to pull down and proves it to be too risky. Or, you can do it as a trilam, thinner pieces bend easier. Or, you can run the hickory into the bandsaw for 17" to create a saw kerf, then glue a 17" hickory lam into the kerf, effectively making that part of the bow 4 lams, in which case it will bend quite easily. Just throwin that stuff out there.

[Stick Bender]

Im going to do a dry run just looking for a good starting point Im pre tappering the limbs close to finish , I figured it would take a slow sweep to 6 in. maybe not I will try at 4 in. and go from there ! Thanks !

[Marc St Louis]

I like gluing-in a progressive amount of reflex, sort of like this

[Badger]

  One rooky mistake is to start the reflex too abruptly, pretiller the belly limb so the reflex happens in a long sweeping curve. With a sudden curve and then an almost straight limb tillering is a nightmare and the bows usually break. I would go for 3 1/2" maybe 4" and try to keep 2 1/2"

[Badger]

  I posted the same time as Mark, good example.

[Stick Bender]

Thanks Steve & Marc thats exactly the profile Im looking for I was figuring with 6 in. on the form would give me 3 after spring back & break in but just guess work on my part I am a Rookie on these , I will play with it on the form and down size the reflex to get a similar profile Thanks !

[Badger]

   Stick depending on how close you are to final thickness when you glue it up you might find yourself gaining reflex during tillering. It is good to get pretty close but always err on the side of caution and go a bit thicker.

[Stick Bender]

Well  my core is at 3/8 hickory ,bamboo 1/8 is where Im starting , limb split into 4 ths 1/16 th tappers
I was figuring on a 45 lb bow but like I said every thing is guess work on your first one of these ,Im 1 3/8 max width  originally I was thinking 66 ntn but wasn't  sure it would take my 29 1/4 draw so I streched it to 68 1/2 in hind site if I knew I was going longer I would have ground the core 7/16 !

[Stick Bender]

I went back this morning and looked at Dean Torges vid and for this type bow he he puts in about 3 in of reflex at the tips and 2 blocks  that keep the limbs neutral about the fade area and the profile looks about the same as Marc posted and Steve described , Marc's might be a little bit more then 3 in. as it looks in the pic but I'm going for the 3 in. on the first and hopefully will have a good feel for it after this one  I'm also going back to the 14 in. riser as it will keep 2 nodes more out of the fade area and give me better node placement along the limbs ! Half the fun on making these bows is working all the bugs out Thanks for the help !

[bradsmith2010]

thats gonna be a nice bow,,

[Stick Bender]

Thanks Brad hope your right !

[bushboy]

With lam bows,prep is everything!pretiller like Steve said"I also like to hit the boo with a bit of heat to make sure it follows the contrours.i find the bamboo will triple the draw weight.

[Stick Bender]

Thanks BB  I'm pretapering the core I have the boo down to 1/8 thick at the crown and 1 5/16 width the core I'm at 1 3/8 for a minor trap sense I'm pulling it to 29 in. I didn't start the limb width tapers tell past mid limb  hoping for 45-47 @29 1/4  I'm doing my best to get it to tiller off the form , will see !

[Stick Bender]

Got every thing ironed out  I think, nothing fancy but here is the finale design 70ttt  1 3/8 w tell 12 in. out of the fades then strait tapper to 1/2 in.  12 in. Riser , 3 in. Of progressive perry reflex like was suggested  hoping to hold 1 3/4in. 45-47 @ 29 1/4  that's a lot of wood hanging out hope it has some decent speed but looking for a decent 3 d lower weight bow !