Couple O Questions about backing and flipping tips...

[hurlbri1]

It's been a while since I built any bows.  I am far from an expert.  Got a few shooters, but that's it.  My big disappointment is the one I made my 6'4" buddy as a gift.  He broke it.  Drew it to his ear instead of his chin...a few extra inches...it wasn't spectacular, but I felt horrible...not that I'm good enough to be making bows for others but he loved our shoots out in Michigan and he was the best man at my wedding...couldn't resist.

I mention that because now I'm a bit scared so I want to try backing...and flipping the tips since I seem to get a bit more set that than I like.  I got a nice rift sawn ash board.  72" tip to tip. 2 inches wide at the fades.  Pyramid design to 9/16" wide tips.  I want it to come in around 30# at 28" when it's all said and done.  I'm considering this my "practice bow" before making my friend another.

Question #1 order of process.  As I read through here on all the great build alongs and past advice, I see the process as: 1) Get a decent tiller--past floor tiller, but before final tiller--no hinges, bending evenly and smoothly 2) Flip tips 3) back bow (in my case, I'm going to try the dog bone rawhide) 4) finish tillering. 

So, is this the right order?  Do I need to completely tiller first, then flip tips, THEN back and adjust? Or do I flip tips first, then tiller? 

Question #2: Radius for flipping tips.  I read somewhere in the PA archives to make the jig using a 1 gallon paint can to get the curve right.  Is that a good ball park? The whole idea for flipping tips is to combat string follow.  I know my technique sucks, but all I got right now is whitewood board bows and I can't seem to keep the string follow under 1.5".  Now I've seen Pappy's build along where he steams the ends and flip the tips using just gloves and his knee!  Amazing!  But I'm not there yet

Thanks for any feedback you can provide!

Cheers,
Brian

[Wooden Spring]

The way I do it is to first cut out a 6' long, 2" wide, and 1/8" thick piece of hickory (my backing of choice), and glue it to my belly wood (6' long, 2" wide, and around 5/8" thick red oak, or jatoba, ipe, or purpleheart, or whatever...) over a curved form - usually imparting 3 inches of reflex into the board stave. (Don't forget to glue on a handle at this point as well)

I made my bow form by laying out a 2x8 on my shop bench, marking my center and ends by driving nails into the board, then bending a thin batten around the nails to define my arc, then mark that with a pen. If you've got any questions about how exactly to do that, just do a Bing search for "boat lofting with battens." I'm from eastern NC, so I tend to use a lot of boat building tricks in my woodworking. It's fun, plus I get to say "Arrrgh" a lot. 

[wizardgoat]

If I add recurve to my tips ill do quite early on.
I'll make my tips wide, about 3/4 to an inch, and about 5/8 thickness, and really try
to make both tips identical, so they bend, and keep the same amount of bend. Narrow them later.
paint cans are a good size for radius, but if you really dont want to see string follow build a caul and buy a heat gun. Theres a build along on here sonewhere.
if I back a bow and know from the start, theres no harm in doing it really
early on. I usually do it before I brace it.

[Wooden Spring]

"I can't seem to keep the string follow under 1.5"."

Actually, that's AWESOME!   Don't let anyone ever tell you that string follow is a bad thing. When you see a bow that lies straight when unstrung, you can rest assured that the bow started out with some amount of reflex - whether glued in with a backing, or heated into the wood.

When a bow has got some string follow, they are more pleasing to shoot - less handshock. Yeah, you get a little less velocity, but who cares? A deer, nor a target are going to care if your bow is shooting 130 fps or 140 fps.

[PatM]

At that velocity a deer might.

[scp]

At that length and draw weight, you definitely don't need to recurve the tips. When I "flip the tips," I don't think I'm making recurve bows but just reducing string follow by reflexing the tips. Therefore I never flip the tips until most of the tillering is done. I simply leave the tips at least 1/2 inch thick for the last 12 inches or so. If the string follow is less than 2 inches, I would not bother. If it's more than that, I would simply use a heat gun to put a nice mild curve in that 12 inch section to remove most of the string follow. If you do more than that, you would probably just increase the set. Another way would be to reflex the whole limbs by heat treating them, just enough to remove all string follow. Good luck.

[Wooden Spring]

"At that velocity a deer might."

Well, at least until he bleeds out.   

[bradsmith2010]

I dont feel any difference in hand shock if a bow follows the string or not, if it is well made, and a bow that has great cast for its draw weight is more pleasant for me to shoot,

[PatM]

"At that velocity a deer might."

Well, at least until he bleeds out.   

 "If"

[Jim Davis]

"At that velocity a deer might."

Well, at least until he bleeds out.   

 "If"

Rather  surprised to find a velocity cheer leader  here.... Of course, I'm in Kentucky, where the hunting regulations specifically state that there is no draw weight requirement for bow hunting. I've yet to see or hear of a deer wandering around with a superficial arrow wound in  the chest... And then there's the whole speed/inertia/momentum flogging of dead horses.

[PatM]

I would hope that we aspire to more than 130 or 140 fps though.

[Jim Davis]

Yes

[PEARL DRUMS]

I dont feel any difference in hand shock if a bow follows the string or not, if it is well made, and a bow that has great cast for its draw weight is more pleasant for me to shoot,

THANK YOU BRAD! Man Im tired of hearing that get passed along. bows that follow the string can rattle teeth as easily as any other poorly built bow.

[Badger]

  I never could figure out why string follow bows supposedly don't have shock. If you build an efficient bow, tillered to match it's design it won't have shock or at least much shock. You can shoot feather light arrows out of a well designed bow and not have any shock. As for string follow, hard to avoid but I believe we should always strive to avoid it. Better designs, proper seasoning of the wood, careful tillering and monitoring of the wood durring the tillering process and experience will result in less string follow and better performing bows. Sometimes it is hard to judge set on a heat treated bow because it is hard to say how well the profile has been set in by the heat. If you loose a little of your profile right off the bat and then it stops changing that can be a good sign.

[hurlbri1]

I just wanted to say thank you for all the thoughtful comments!  As far as hand shock goes, I really do not have the experience to even tell the difference so I am ok with the string follow/ hand shock argument.  But I agree with Badger's thoughts on string follow: that it is an indicator of poor design or inattentive tillering.  Until I get better though, I thought the stop-gap would be to flip the tips.  Plus, it's something different to try as I work in improving my bow building skills.  And I've never shot a bow with flipped tips!  Thanks again for your input!