Pre-Stretching a New String

[Emmons]

How long do you string makers pre-strech your strings for?  I just twisted up a new string and set-up a strecher.  I have two ratchet stretching the string between two tree in my yard.  I proably have about 250 pounds on it now and need to know how long you would leave the tention on the string?  By the way it is a 10 stran Dynaflight 10 with padded loops.
 
Thank you,

James

[T Folts]

I dont know how many pounds I have on my strings but I leave them about a 1/2 hour with lots of tension, seems to work good. Some leave them over nite but I dont.

[A.S.]

I give mine at least an hour, starting at 300#

[McDave]

When you guys stretch your strings, is it just because you don't want to go to the bother of adding more twists the first few times you use the string, or is there some other reason?

[Randy]

I let my new strings stretch overnight with a 15lb weight hanging from them. I make my strings from dacron for my selfbows. Never had a problem doing it this way.

[Over&Under]

Originally posted by McDave:
When you guys stretch your strings, is it just because you don't want to go to the bother of adding more twists the first few times you use the string, or is there some other reason?

I was wondering the same thing...good question Dave.

[X2]

250 lbs for about 2.5 hrs.  I pre stretch them to get everything settled in, so I can then put on the serving, and not have much adjustment after I get it on the bow.

[Swamp Yankee]

Dacron can takes weeks to settle in and stop creeping; pre-stretching it makes sense.  FF, not so much in my experience.

[Razorbak]

stretch on a jig that can generate at least 300# for a hour then let relax for at least 1/2 then serve..will have no issues..when I do this..never have to worry about my BH after that

[Cyclic-Rivers]

I usually string them on the bow and then rub it with a piece of leather before I serve it. It will still stretch after I shoot it some. (B-50 and B-55).

I have a friend that hangs a heavy bucket one one end and hangs the other end on a nail in the rafters. he sticks a handle through the bucket handle to keep it from spinning. hang it for one day or night and he's usually good to go.

[L82HUNT]

Prestretch is the way to go.  I made enough of different strands and material and have it figured what each string will stretch.  
 A 8 strand D10 I will make .75" shorter then I want it to finish while the same string with ultracam will be.50" shorter.

 I stretch at 125 lbs at min of 3 hrs.  Once this done they will require little if any brace height adjustment once there put on the bow.  Its just nice to have a string ready and not moving on you them first couple hundred shots.

[Emmons]

Thanks guys,

I stretch the string for three hours at around 250 pounds.  It stretch out about 3/4".  

It is now on the bow ready to shoot tomorrow.  I hate mess with a bow in the middle of the season, but the old string was cut half way thru on the top loop.  This was the second string to do this in less then 500 shots.  So I ran some 400 grit sand paper thru the string groove to smooth everything out, then put a light coat of tru-oil on it.  Hopefully this one will stay together.  I got everything transfered over from the old string and will see if the tune changed tomorrow.

[JamesKerr]

I stretch mine over-night on my bow. Once they have been strung on the bow for atleast 12 hours they are good to go.

[ironmike]

i use b50 and make flemish strings,string bow and use the bow like a gym set. put my feet on the string and pump the bow a couple of dozen times,watching carefully,serve and shoot..

[Bowjunkie]

150 pounds for a minute or so. B-50

[Stone Knife]

I just put mine on the bow and leave it strung while i shoot it in, I add twist as needed till it quits stretching.

[frank bullitt]

Pre-stretching strings, it's more a quality issue for a maker. When building for either a bowyer, supplier, or individual customer, you want the length to be correct! And without alot of adjustment, twisting, when installing the string and fine tuning.

Just good business. When AMO set standards, stretching a string at 100lbs was used to determine proper length, in the industry.

But, with the popular use of Flemish twist type strings, it helps to settle the loop and neck twists sooner, again for the customer's ease!

[David Mitchell]

I'm with Stone Knife--never stretched a string other than putting it on the bow and pressing the limb tips to seat it in good and then just leave it strung maybe overnight. Even with my plain old dacron strings. It's always been fine that way--sometimes I think we over-think this stuff too much.  Guess I'm just an old timer who doesn't get all this stuff people think they have to do.....Oh, and Merry Christmas.  

[Buckwheaties]

X2 David Mitchell.

[frank bullitt]

Excuse me, overthinking what?

You said you put it on the bow, press down on limbs, to apply "extra" force ... weight, to the string. Let sit overnight to stretch. Correct?

No different, just a little faster getting to proper length, ...brace.