R/D side profile design question.

[mtblucas]

Hi everyone,

I’m curious what kinds of things you are thinking about as you design the side profile of an R/D bow. Are there any rules of thumb? Can you just come up with any old curve for the limbs or is there more to it than that? Having never done it before I’d assume as long as the curves are all blended well and flow smoothly from one tip to the other it’d be good to go.

The reason I’m asking is because I just finished routing the bottom half of a form using Bingham’s 64” R/D template and think I may want a little more reflex at the tips. I’m contemplating increasing the curvature of just the outer half of each limb to achieve about 3/8 more reflex. I just wanted to see what y’all thought before I go altering Bingham’s tried and true design.

[kennym]

I added an inch on my 64" to make the modified version. It added 5# and 5 FPS to the design.

The tips were barely ahead of riser back (pointing it at target) unstrung and it was a sweet shooter. I had thought about it for a few years and thought, I gotta know.


It didn't really hurt the shootability but doesn't look as much like a longbow now.


IMO , I wouldn't put those tips more than 2.5" ahead of riser. Been there done that.

[C. Johnson]

A couple of things here.  In my experience, a guy cannot go wrong with one of Bingham's designs.  You will end up with a smooth shooting bow with good performance without reinventing the wheel.  What fun is that though?

I've noticed the further I put the tips past the riser, the less stable the bow becomes.  What I mean by this is that the bow becomes a lot less tolerant of inconsistencies in the shooter's form. 

Push the tips too far forward and you start to stray into recurve territory.  Before long, you'll be building those too.

[mtblucas]

IMO , I wouldn't put those tips more than 2.5" ahead of riser. Been there done that.

Thanks Kenny

The design actually is very shallow so the tips would probably only be an inch forward of the riser with the added reflex.

[mtblucas]

Push the tips too far forward and you start to stray into recurve territory.  Before long, you'll be building those too.

I have no doubt a recurve is in my future

I thought reflexing the tips ahead of the riser resulted in a better shooting bow. It sounds like you just gain speed but lose stability then? I assume there is a happy medium. As I mentioned responding to Kenny above, the tips still won’t be very far forward even if I increase the reflex. Still, you have me thinking I should maybe just leave it be.

[Roy from Pa]

I've played the more re-flexed tips game.

There comes a point where you go from a stable well preforming bow to a radical troublesome failure bow.

A lot of guys here have been where you are and where you want to go.

I would listen to the guys info above.

[kennym]

Yup , I can send you one from the corner of shop that has about 4" ahead of bow back.  If you ain't on your A game you miss stuff....


Hunting speed and failed there too... Glad I'm over that!!

[Bowjunkie]

If ya wanna do it, do it.

Binghams plans are a safe baseline.

3/8? That won't matter.

Rules? After a certain point I stop offering advice, and instead recommend...."Don't ask.... just DO it".

Spoon feeding makes for a reliant bowyer. Reliant bowyers don't think on their feet or advance their own crafting or our collective one.

I'll help ANYone when they need it, but will spoon feed NO one. Sorry if this sounds harsh... but it works.

[Roy from Pa]

Bowjunk..

Ya got a pm:)

[mtblucas]

So I think I just came up with a great idea. I’ll make a bow using Bingham’s plans, then I’ll make another after modifying them slightly. I mean why not right? Two bows are always better than one. I Wouldn't mind adding a couple R/D’s to the collection and comparing how they shoot.

[Shredd]

  What these guys said here are pretty on,  But you just gave yourself the best advice there is...  That is how you learn...

   If you want my 2 cents...  The curves don't mean chit if your lams aint right and visa versa...  It's about having some decent working curves and having those lams working with those curves...  It takes a  bit of time...  Just change one small thing at a time and keep lots of notes on everything...

[Forwardhandle]

I just got done modifying a KM design it was 3 in ahead of the riser and a stable bow unfortunately blew up do to botch glue up but I'm working on another of it this morning but the thing I noticed was the more reflex the more brace height needed so I'm sure there is a trade off some where between reflex/brace height /performance ,I'm not convinced reflex alone is the factor in shoot ability of a bow I personally think it's a combo of the over all design !

[Roy from Pa]

I'm not convinced reflex alone is the factor in shoot ability of a bow I personally think it's a combo of the over all design !

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