how many B-50 strands for 70#

[ozy clint]

how many strands of B-50 dacron should be in a string (endless loop) for a 70# recurve (bob lee). i was going to make it 16 strands, is that enough?

[DBerrard]

Whats the tensile strength per strand..#45 or something? Does it matter which brand the string is?

I haven't made any strings but judging on its strength the normal 12-16 strands should be more than adequate..unless you need more for an endless loop?

Apologies for adding more questions bud..interesting topic to me though.  

Regards,
  Dave

[Falk]

Clint,
16 strands B-50 is more then enough. If you need to play for nock fit, you can go down to 12 and don't need to worry the string will breake on you. Maybe you would like to reinforce the loops in the later case - mainly to built up the diameter here.

[ozy clint]

might try a 14 strand string as the 16 strand is a little tight on the nocks. but in saying that a string with a couple more strands in it has benifits in the wilderness. break a strand for some reason and you're still good to go. i think that was an old fred bear trick.

[Falk]

Hmmm?! From the really old days of hemp and linen strings there is an old saying which goes like this:
"Any archer is only thus good - as his spare string!"

Strings are way overbuild with modern fibers anyway - even B-50. Aside from tuning, which might call for a higher number of strands, why would you want to shoot, say 2000 arrows, with an unnescessary fat string, only because you might then slice one with your broadhead by accident?!  
What you can save in mass in the string you can later add to your arrows to your advantage. And a spare string will fit in every pocket or quiver. Just a thought ...

   Falk

[ozy clint]

yes that is a worth while point of veiw. i'll definitely try 14 strands.

[Danny Roberts]

My 63 # mulberry shoots great with a 16 strand. The classic nocks fit more snug on it also.

[nutmeg]

I would go with 16 strands.(nut)

[Orion]

16 strands of dacron has been the standard for bows in the 60# range for a long time.  A general rule that comes to mind, is something like the string breaking point should be some multiplier of the bow weight, ten, I think. That yields a large margin of error, of course.  70# times 10 equals 700 pounds.  16 strands times 50, the breaking strength of one strand of B-50, equals 800 pounds.  But keep in mind that with a continuous loop string, only half of those strands (8) are going around the nock.  Personally, I wouldn't go less than 16 strands of dacron on a 70# bow.  That's what I used when I shot 70# bows a few years back (quite a few).  Some use 18 strands for that weight.  You can get the nocks to fit by using a thinner diameter serving. Good luck.

[Mark Hedges]

I think 12 strands would work but you would have a lot of problems with the string stretching and screwing up your brace height.  With a 70 pound bow and B50 you will have problems anyway even at 16 strands. Are you planning on keeping the bow strung?

If you want to use carbon arrows you will probably have to work on the nocks some to get a good fit. I couldn't even find a nock that fit a 12 strand string properly!

Mark

[George D. Stout]

The string stretch will stop if the string is made correctly.  I rarely have to adjust the string once it has been shot about two dozen times.  I would go with the one that gives the best nock fit.

[fingers]

Dangit!I must be doing it wrong again as I made a 14 strand string for my 65# longbow. It seems to work just fine though and the nocks fit just like I like them to. I think I'll risk it