Adjusting width for mass

[Nasr]

I have a problem with my bows turning out too heavy in mass about 3 ounces over. Should i start out with a narrower limb next bow? Latest bow i built is a white oak straight limbed bow about 60 inches ntn 1 3/4 " wide and fade half way threw the limb its not done yet but it its currently weighing 20.5 ounces and i am aiming for a 50 - 45 pound bow at 28 " now in this bow i dont mind it being a little heavy as it has a problem area near the tip on both limbs so i dont mind the extra weight to keep it together but i can never predict how much width i should remove to end up with 18 ounces . So assuming everything is the same draw length weight and length how wide would you go if using the same wood.

[Del the cat]

Easy solution... don't weigh them.
I've only ever weighed a bow illustrate to a modern target archer how ridiculously heavy their set up is.
Del

[Nasr]

lol that is one solution but i want to get the best performance out of my bows.

[jeffp51]

I am with Mr. the Cat on this one. While I love to read about others experiments with speed, mass, and set, I don't feel the need to follow suit. "The best bow possible" can be so many things.  Make a piece of wood bend, draw it back, and loose an arrow. That is what it is about to me.

You might get speed at the cost of durability. You might get both.  If you want fast durable, accurate, and deathly, get a compound with sights and counter balances.

Most of all, make the bow that makes you happy. If that is one that is super light, then try new things with the next one. If it breaks, try something else

[jeffp51]

That's a long way of saying I don't know how narrow to make a bow

[Nasr]

Jeff while i can appreciate where you are coming from i dont think there is anything wrong with chasing a faster bow. And i would never shoot a compound bow. Its also more of how much i can push myself as a bowyer. if i just wanted to make bows and not push myself i would make fiber glass laminate bows. i can always narrow the limb till i hit my mass i just thought maybe there was a better way of doing it so i wouldn't lose poundage. 

[Del the cat]

I think you are missing the point...
It's the performance that matters not the mass... I can saw any old log to any mass you like and it doesn't become a bow.
The mass principle is a tool and like other tools it needs to be used with skill and understanding.
It's a bit like the whole building a bow by numbers thing, yes you can rough out to dimensions if you have a good clean stave, but in the end you have to use your eyes and your feel to tiller anything that isn't homogeneous.
You don't just narrow the tips to hit a weight and risk spoiling the tiller any more than you drill a big hole in the grip to take off some weight.

More seriously:-
If you wanted to remove mass from a well tillered bow, it would be best removed evenly along the length. I suspect you can loose mass from the inners without effecting performance more easilly than you can from the tips, as there is more width and thickness there to start with.
Del
There's an old Yorkshire saying...
"You don't fatten a pig by weighing it!"

[George Tsoukalas]

NASR, have you had success making white oak bows 60" long ntn  for a 28" draw?
If yes, then we should be asking you questions. Seriously.
I like my bows 64" for a 26" draw.
If I had to make someone a white oak bow for a 28" draw I'd go 66-68".
I've weighed completed bows a couple of times. Can't help with mass theory much. Maybe Badger will check in.
Jawge

[Badger]

      Nasr, the mass is just a suggested mass that will have you in the right ballpark for various designs and draw weights. If your bows are not taking excessive set I think you are ok, 20 oz doesn't sound heavy to me. How long is your handle and fade area? Are you using any reflex? Are your outer limbs a bit stiff? With the mass principle you add a bit of mass for anything that might increase the strain on your bows. Most of my 50# bows used to come in around 18 oz now the majority of them are coming in between 20 and 24 depending on reflex, handle and length of bow.

     If I am coming in heavier in mass than I really need to be I start refining the sides of the bow when it is out to about 18" on the tiller tree. I have a hickory bow I am working on now that should weigh about 21 oz when finished. It is currently at 30 oz and I am at 15" on the long string. Every time I come off the tiller tree I use the scraper on the sides as well as the belly to refine it a bit more as I go.

[Nasr]

Badger the handle and fade is 8 inches long i heat treated some reflex across the whole limb no re curves or anything on this one do to the tips having a problem and did not want to risk breaking the tips when bending them. The set right now after pulling it to about 24" is about .25 " i reheated the belly but not too much just enough to get a slight color and hopefully will be pulling it to 28 inches tomorrow if it goes well ill post pics

[Nasr]

NASR, have you had success making white oak bows 60" long ntn  for a 28" draw?
If yes, then we should be asking you questions. Seriously.
I like my bows 64" for a 26" draw.
If I had to make someone a white oak bow for a 28" draw I'd go 66-68".
I've weighed completed bows a couple of times. Can't help with mass theory much. Maybe Badger will check in.
Jawge

Lol i just finished a deflex reflex white oak bow about that length that came out a little over 50 pounds @ 28 inches. White oak is amazing wood now granted i havent worked with much varietyof wood  but it seems to do what i want from it and more. Its really hard to break and once you heat treat it it doesnt take much set. also when i bend some recurves it bends really well to dry heat. But to be honest i might be pushing it too far at only 60" ntn but ive done it before and this piece of wood could not be any longer as 62" was all i could use from that piece and i will not settle for anything less then 28"

[Badger]

  That bow should be at least 20 oz or more, your non bending handle and fade area is more than 8" and you have some reflex. 1/4" set so far is fine. Send me a message and I will explain how to use that formula. I have a little download calculator I can send you where you just feed in the information and it gives you a suggested mass.

[Nasr]

Jus tsent a message thank you soo much

[Jim Davis]

I agree with George. If you got away with a 28" draw on a bow that short, you have pretty near used up your luck.

Although, a wide thin limb might work.

[Nasr]

I agree with George. If you got away with a 28" draw on a bow that short, you have pretty near used up your luck.

Although, a wide thin limb might work.

 Ill take your word for it guys i dont usually go this short but like i said before the reason as to why i did was in the piece of wood and not of my own preference. i usually like them 64" to 66" but this piece had some really bad grain towards the end of both limbs. i have however made bows that short and at that draw length. They werent that heavy and i can only remember a couple. I dont think it counts but i just finished a reflex deflex of the same length at 28 "  but then again its reflex deflex and probably not as stressed.