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theTarget
09-09-2010, 12:09 PM
how is the string length in the martin specs measured?
Is it the length of the finished string that has twists already or do the specs give the string length without twists?

If the specs include twists:
- how much twists per lenght (per inch?)
- how much do I have to make my own string longer so that it will be twisted down to specs?

If the specs do not include twists:
- how much twists per lenght (per inch?) are recommended?

Montalaar
09-09-2010, 12:17 PM
Strings are measured with twists in it under a pressure of 100lbs and with string posts on each side of 0.25" in diameter.

It is up to you how many tiwsts you put in a string. Some put one twist per two inches, other put one twist per one inch or even less. I prefer 1 twist per 1.5" to have some room in both directions.

That depends on how many twists you put into your string. That is a thing of experience and depends also on the pressure you out on the string while prestretching and some other factors.

theTarget
09-09-2010, 12:25 PM

Is there a starting point of length for string making? How much longer do you make your string to get the final twisted length as in the specs? Can you calculate this as percentage, because strings and cables are different length?
E. g. like: use 2% longer distance of string pegs to get the final twisted length?

scepterman30x
09-09-2010, 12:57 PM

Is there a starting point of length for string making? How much longer do you make your string to get the final twisted length as in the specs? Can you calculate this as percentage, because strings and cables are different length?
E. g. like: use 2% longer distance of string pegs to get the final twisted length?

I like to use 1/2 a %, for instance if you string is 100" long multiply that by 100.5% or 1.005. Either way it will give you 100.5" or if your string is 50" it will end up at 50.25".

Destroyer
09-09-2010, 03:03 PM
Strings are measured with twists in it

Is this official or just your opinion?

Montalaar
09-09-2010, 03:31 PM
This is official.

There is no sense in measuring a string without twists as their is no rule of how many twists should be in a string.

If you order a string at any string maker he will send you the strings at the length you ordred with a certain amount of twists in it. If they are longer you should send them back.

Furthermore:
If you remove the strings from a factory new bow and measure them they will have the exact lengths that are written on the tech charts. WITH twists.
Also:
If you make a string you NEED to twist it as you can only serv it WITH twists in it. If you put the serving onto the string before twisting it you will always have certain peep rotation and a bow that will never tune in as easy as others.

Destroyer
09-09-2010, 07:13 PM
There is no sense in measuring a string without twists as their is no rule of how many twists should be in a string.

Minimum 15 twists as far as I know. Always done this and makes sense to me, its not that precise a length. The spec length is just a guide, a length that will give the right specs with at least minimum twists in it. There is a fair bit of allowance, you can always add some length and twist some more. Its pretty easy to do that. Most bows the same model will work out very similar.

If you order a string at any string maker he will send you the strings at the length you ordred with a certain amount of twists in it. If they are longer you should send them back.

Most of the twists in the string are a result of the current trend to do it before center serving. Then put as many twists as needed to get to the specs. This is great for them, so if the string is a bit long (made that way) a few more twists bring it up to spec. This way they don't waste as much. This doesn't make them the right length though nor does it prove anything. Mine have needed to be twisted up more to get the DW, DL, ATA.

Furthermore:
If you remove the strings from a factory new bow and measure them they will have the exact lengths that are written on the tech charts. WITH twists

Not on mine and due to manufacturing, they can't always turn out correct, each bow is different.

Also:
If you make a string you NEED to twist it as you can only serv it WITH twists in it. If you put the serving onto the string before twisting it you will always have certain peep rotation and a bow that will never tune in as easy as others.

They always use to make strings without twists and I doubt that the center serving causes the peep rotation.

Sorry but this sounds like opinion to me. Someone from Martin could settle this. If it is or isn't, I'm happy either way, I just like to officially know.

:)

Montalaar
09-10-2010, 12:13 AM
Oh, c'mon Destroyer. If you do not believe me go to AT. There are some professional string makers. They will ALL tell you the same. You could even send an email to the 'big ones' and will get the same answer.

Montalaar
09-10-2010, 12:19 AM
Minimum 15 twists as far as I know. Always done this and makes sense to me, its not that precise a length. The spec length is just a guide, a length that will give the right specs with at least minimum twists in it. There is a fair bit of allowance, you can always add some length and twist some more. Its pretty easy to do that. Most bows the same model will work out very similar.

That may be right.
But it does not influence the facts that a string is measured WITH twists.

Most of the twists in the string are a result of the current trend to do it before center serving. Then put as many twists as needed to get to the specs. This is great for them, so if the string is a bit long (made that way) a few more twists bring it up to spec. This way they don't waste as much. This doesn't make them the right length though nor does it prove anything. Mine have needed to be twisted up more to get the DW, DL, ATA.

Not on mine and due to manufacturing, they can't always turn out correct, each bow is different.

They always use to make strings without twists and I doubt that the center serving causes the peep rotation.

Sorry but this sounds like opinion to me. Someone from Martin could settle this. If it is or isn't, I'm happy either way, I just like to officially know.

:)

I do not think that you will believe me as your opinion seems deadlocked.
There is no trend in putting twists in a string. This has always been done even before there have been hightech materials in Archery. It is right that there can be the need of putting or removing twists to fine tune the bow. But this is not the rule.

If you put too many twists in a string that has been served under a certain amount of it the string will stretch and the peep will rotate. You may even get broken strands under the serving. But is i already mentioned you seem a bit deadlocked to me.

scepterman30x
09-10-2010, 05:32 AM
It amazes me how many folks believe that if you sell string on AT you become a professional string maker. I have been making strings longer than some have known what one is (figure of speach but you know what I mean).

I will shed some light on a few of the reasonings why you twist a string.

For one it makes the string bundles round and not flat. They need to be round for consistency in tension.

2. The strings strands do not occilate so it is usually more quiet.

I put 1 twist per 1.5" in string length, this is a good "happy medium" and works great for me.

Another thing I do to avoid string twist while serving is serve the ends toward the loops (think about it...it is harder to twist a shorter section than going toward the longer section when serving) and then serve the center last.

and last and very importantly I serve all my strings...end serving, center serving etc. after twisting and while still under about 300 lbs. of tension.

Take these steps and you should have little to know peep rotation.

I have built a lotta strings over time and I can almost guarantee I have no to very little peep rotaion without a shoot in period.

P.S. Montlaar is definatly correct in saying that serving after twisting and under while under tension is definatly the correct way to do it and avoid much if any peep rotation.

Montalaar
09-10-2010, 07:39 AM
It amazes me how many folks believe that if you sell string on AT you become a professional string maker. I have been making strings longer than some have known what one is (figure of speach but you know what I mean).

Scepterman, i know that. But even VaporTrail started there and that is what i referred to. There are some people at AT selling strings with no knowledge. I learned making strings for Recurve aroudn 6 years ago in my archery club. It is quite common to make strings yourself with most Recurve archers so around 80% of people here shooting a bow do also know how to make one. The Compound archers just fear the allmighty peep rotation so they do not make their own ones... Which i do not understand. All my bows are running with my own strings.

Strings with one turn per 2" of string, stretched and served under 300lbs after putting the twists in it.

scepterman30x
09-10-2010, 07:57 AM
Agree. I was not contradicting what you said. It was more of an addendem to it.

Montalaar
09-10-2010, 08:38 AM
I understood it so. Even if my answer does not look like this. ^^

theTarget
09-10-2010, 11:06 AM
thank you for all the info,
but back to the theme:

I also believe that string length in the martin specs is measured as finished string length with twists already in it.
Is there an official statement from martin? I did not find anything in the specs.
Maybe someone from martin can drop in? Would be helpful on the spec website also.

Montalaar
09-10-2010, 12:44 PM
Target, what do you need?

If you want to make your own string:
You already have the lengths. It is your decision to put twists in it or not. But there is no use in not doing so. Important is only that the string has the approx. length when you put it onto that bow.

If you need a new string and you do not want to build yourself one just call ArcheryDirect and get you one. You should also know that you can call them always when you have questions as you purchased your bow there.

theTarget
09-10-2010, 02:24 PM
did not purchase my bow at Archerydirect, nevertheless great shop!
What I wanted is to get rid of the discussion of different meanings measuring string length. If you look at AT there is a lot of discussion about this also.
Did shoot a Hoyt bow before and although it was a great bow, even this manufacturer did not make a official statement about the subject. :confused:

Destroyer
09-10-2010, 07:27 PM
I do not think that you will believe me as your opinion seems deadlocked.

Nope, never is mate. If it was made official then I would be happy even if you are correct. I'm never afraid of the truth. In my 23 years in archery there has been some claims about this and that, I like to hear the actual truth.

But it does not influence the facts that a string is measured WITH twists.

Show me something that proves it please. Nothing you guy's have said changes my mind atm.

If you put too many twists in a string that has been served under a certain amount of it the string will stretch and the peep will rotate. You may even get broken strands under the serving

I've had up 80 twists, never broken a strand, never had much if any stretch because of it. With so many twists it seemed to stretch less, more stable.

It amazes me how many folks believe that if you sell string on AT you become a professional string maker.

Exactly. It doesn't prove how Martin measures the specs either. I can see benefits to making them to a spec with twists, easier for the user to put on that way.

Montlaar is definatly correct in saying that serving after twisting and under while under tension is definatly the correct way to do it and avoid much if any peep rotation.

In your opinion. I thought pre-stretching, creep, had more to do with peep rotation. If your correct, I shouldn't reserve my strings unless I have 300lbs of pressure on it or I will get creep? Don't think so.

Destroyer
09-10-2010, 07:30 PM

This is all I want. Nothing to do with anybody's opinion, believing anybody, just an official statement on how the specs should be interpreted. :)

scepterman30x
09-10-2010, 09:01 PM
Nope, never is mate. If it was made official then I would be happy even if you are correct. I'm never afraid of the truth. In my 23 years in archery there has been some claims about this and that, I like to hear the actual truth.

Show me something that proves it please. Nothing you guy's have said changes my mind atm.

I've had up 80 twists, never broken a strand, never had much if any stretch because of it. With so many twists it seemed to stretch less, more stable.

Exactly. It doesn't prove how Martin measures the specs either. I can see benefits to making them to a spec with twists, easier for the user to put on that way.

In your opinion. I thought pre-stretching, creep, had more to do with peep rotation. If your correct, I shouldn't reserve my strings unless I have 300lbs of pressure on it or I will get creep? Don't think so.

Brother all I was trying to do was enlighten you. FYI...if anything I said was "opinion" I would have said so. However I did not...what said was fact or I would not have said it. Just for the record I don't recall anything about having to take your string off to reserve it. I am strictly talking about how to build a string from its inception not reserving one while still on the bow. Theres always more than one way to skin a cat.

scepterman30x
09-10-2010, 09:07 PM
AMO COMPOUND BOW STRING LENGTH STANDARD
Compound bowstring length shall be designated by its stretched length as
determined by placing the string loops over 1/4” diameter steel pins and stretching
with 100 lbs. of tension. Measurement is taken from outside of pin to outside
of pin. Tolerance is +- 1/4” after 20 seconds under tension load.
EXPLANATION: Compound bowstring lengths have no particular relationship to
bow length and therefore actual string length under load is used for length
designation.

scepterman30x
09-10-2010, 09:10 PM
MEASURING TENSIONS
All 8 and 10 strand bowstrings made from polyester (i.e., Dacron) are to be
measured under 50 +- 1 pound (22.68 kilograms) of tension load. All other
strings and cables for compound and non compound bows are to be measured
under 100 +- 1 pound (45.4 kilograms) of tension load.
Compound and non-compound bowstring lengths will be within a tolerance of +-
1/8” (3.2 mm) when measured under tension load. Compound cables (harness)
will be within a tolerance of +- 1/16” (1.6mm) when measured under tension load.
Tension loads and tolerances are AMO standards, however, bow manufacturer
may specify otherwise.

Destroyer
09-10-2010, 10:09 PM
what said was fact or I would not have said it.

Opinion in my opinion brother. ;) There is a benefit to not twisting the string before serving, the twist can help to tighten the serving.

however, bow manufacturer
may specify otherwise.

We don't know if the chart string length is AMO or just their own, that why I would like official word on it regardless which way is best to make a string. Got off track here a bit.

Montalaar
09-10-2010, 11:51 PM
All Manufacturers have to stick to the agreement they made within the AMO.

I do not see why you are still searching for a reason to stay with your opinion. There is no use to this. But well, there is no sense in a discussion with you in this way.

Destroyer
09-11-2010, 04:11 AM
a reason to stay with your opinion.

Because no one has given me a decent reason to think otherwise.

But well, there is no sense in a discussion with you in this way.

Sometimes I seem to be difficult my friend, but the intent is right. ;)

Destroyer
09-12-2010, 09:25 PM
My reasons for the chart measurement not to have twists included:

1. AMO doesn't exist anymore, now ATA. No mention in the charts of either which Martin would have to do if they were still using them.

2. There is no need to measure them under AMO standards of using 100#, it might be more consistent for length but not necessary to get the bow to specs. Just twist until good. Built many bows over the years with the same method. Quickly measure the string, put minimum twist in, check and adjust if necessary.

3. Both my cable and string measure to spec's in chart without twists and without 100# of tension. They worked out fine.

4. Martin has no statement on the subject and no one has come up with a good reason for there being twists included, just vague opinion.

Have to say I'm still a bit shocked at the reactions here, if people wish to discuss issues, I hope they don't get upset just because they can't prove their point. I enjoy discussing and I will admit when I'm wrong, done so a few times lately and expect to do so in the future too (not too much lol!). I do see others opinions and are not closed minded on this subject as Monty has suggested.

I really wish that there was official word but I'm not holding my breath. It probably doesn't matter that much to Martin. :)

theTarget
09-13-2010, 01:35 PM
I didn't want to stir up a hornets nest here and I nearly do not dare to mention:

I was shooting a Hoyt bow before and contacted Hoyt about this subject and only the second technician I was talking to tried to make a statement. He suggested the length in the Hoyt specs was without twists and you have to twist it to get some final lenght what ever.

I find the statement of Mont is the clearest:
Lenght in spec is the lenght of the string that you have to mount on your bow. it belongs to you if you achieve this lenght with or without twists.

But why does no bow manufacturer (Martin, Hoyt, Bowtech, ...) specify this to clear this question? (Besides, this theme is discussed on AT a lot also)

Destroyer
09-13-2010, 05:20 PM
I didn't want to stir up a hornets nest here and I nearly do not dare to mention

No reason it should. But some of us are very passionate debaters, hey Monty (if you are still here mate, hopefully). ;)

He suggested the length in the Hoyt specs was without twists and you have to twist it to get some final lenght what ever.

What I've been saying and it works.

But why does no bow manufacturer (Martin, Hoyt, Bowtech, ...) specify this to clear this question? (Besides, this theme is discussed on AT a lot also)

Not important to them imho. Besides we shouldn't be messing around with our bows, that's for an 'authorized dealer' to do. ;)

Joan@Martin
09-14-2010, 06:43 AM
Recurve / Longbow strings - Length is AMO (example AMO 60" actual length 57")

Compound bow strings - Length is on finished product. (example if sticker on bow states shoot 90", then the length of the string from end of end loop to the other end of end loop is 90")

Destroyer
09-14-2010, 05:41 PM
then the length of the string from end of end loop to the other end of end loop is 90"

Under tension with twists or just loosely measured?

Joan@Martin
09-15-2010, 11:39 AM
Under tension with twists or just loosely measured?

Some tension, but not a measured specific tension.

Destroyer
09-15-2010, 07:23 PM
Thank you Joan@Martin. :)