New strings on Allegiance.....just an FYI
01-25-2009, 06:07 PM
#1
Nontypical Buck
Thread Starter
Join Date: Feb 2003
Location: Central PA
Posts: 2,299
New strings on Allegiance.....just an FYI
Replacing strings and cables – binary cam bows.
I thought I would pass this along to anyone who is thinking of or in the process of replacing strings and cables on a binary cam bow such as a Bowtech or Elite. This is my personal experience and what I did to get my bow to where it was when I bought it. I find it much easier to get a bow to factory spec and retune rather than trying to get it exactly as it is after you’ve had the bow for a year or two.
First thing is first. Buy a good set of strings and cables! There are many good string makers out there that can provide you with a good, stable set of strings. I am not mentioning names as this article is not meant to sell a product.
The first thing you need to do is take measurements off of your bow with the old strings. Axle to axle length, brace height and draw weight. Also, make note of where your timing marks are currently. Keep in mind this is only for reference. Chances are, your bow as it sits now has some measurement out of whack. Most manufacturers, including Bowtech have a +- of .25” with specs.
Before touching anything, it’s a good idea to take a few digital pictures of the bow, particularly the cams. This will serve as a reference as to how the strings and cables are routed around the cams. I also like to take a pic of how the cables cross below the cable guard.
Put your bow in a press and relieve tension from the strings and cables. Remove the modules from the cams as it makes it easier to get the old set off and the new on.
I pre measure the new strings and cables before I ever put them on the bow. AMO specs say to measure string and cable lengths under 100lbs of tension from the end of one loop to the end of the other using a ¼” post. I have a 2x4 that has a ¼” post on one end. I then measure from the far side of the post to the exact length the new cable must be and make a mark on the 2x4. I then take my digital bow scale, the one I use to check draw weight and hook one end of the loop on it and the other loop on the post of the 2x4. Pull tight until you reach 100lbs of tension and see if your cable is the length pre-measured on the board. If it’s too long, add twists until you get the correct length under tension. If you don’t have a scale, that’s OK, just pull as hard as you can and take the measurement.
Once this is done, put the new cable on the bow, being careful to not add or remove twists from the cable. Now, move on to the next cable and do the same thing.
For the string, do the same thing. When I take the old string off, I put it on my measuring board and measure the distance each set of speed nocks are from the ends so that I can put the new speed nocks on in the exact same place the old ones were. Then, measure the new string and make adjustments to length as needed and put it on the bow.
Put your modules back in the cams and ensure that everything is exactly the way you took the old set off. Install your cable slide as well.
Relieve tension the press being careful that the new strings and cables seat in the cams correctly. Now is the time to put your nocking point or string loop on and square it with the arrow rest. If you use a drop away and it is tied to your downward stroking cable DO NOT set it up at this point. Measure axle to axle and brace height. They should be right on spec at this point. Pull the bow back a couple of times to really seat the strings.
Now, the most important thing is to get your bow to reach max poundage and the correct draw length. Bottom out your limb bolts to max the bow out and then using a scale, check your poundage. If you have a draw board, use it to check your draw length. If you don’t, draw your bow with an arrow and have a friend measure the arrow at the point where the deepest part of the grip and the arrow intersect.
If your draw weight is low, at equal half twists at a time to both cables until draw weight is restored to maximum. Double check your draw length. Keep in mind that adding twists to your cables will lengthen draw length and removing will shorten.
At this point, you’re bow should be very close to specs. Now you can move on to cam synch and timing.
The idea here is to have both draw stops on the cam modules hitting the cables at the exact same time. If you have a draw board, use it. If not, use a ceiling or wall mounted hook to slowly draw the bow down. It helps to be at eye level with the cams when the bow is drawn. Watch the cams break over and hit the stops. You want them to JUST touch the cable, not push the cables toward the bow. If one cam is touching before the other, add a half twist at a time to that cam until they are both in JUST touching. It also helps to slide the draw stop peg out of the way when doing this. Once this is accomplished, draw the bow and have a friend slide the draw stop tight to the limb, compressing the o-ring on the stop peg. Now, you can further fine tune this adding equal twists to both cables to pull the draw stops about 1/16” or 1/8” of inche from touching the cables at full draw. The idea here is that the o-ring will compress and account for the final 1/16 to 1/8 inch of travel and land the two draw stops on the cable slightly. This will also restore you to 80% letoff.
Now you can setup your drop away rest and go shoot the bow for a while to settle the strings in. Once you do this, recheck timing. It might have moved a bit and you need to further fine tune it. It is recommended to install the drop away pull cord as far down as possible on the cable to limit the distorting that happens. This distortion throws the bottom cam out of synch by creating a “shortening” effect of the cable. Once this is done, your bow should be in spec, 80% letoff, max poundage, correct draw length, and synched cams.
Put your peep in and adjust its rotation as necessary and shoot away.
Credit to Dave Nowlin on AT for a lot of this. He’s a binary guru and helped me out tremendously getting my bow setup the correctly the first time.
I thought I would pass this along to anyone who is thinking of or in the process of replacing strings and cables on a binary cam bow such as a Bowtech or Elite. This is my personal experience and what I did to get my bow to where it was when I bought it. I find it much easier to get a bow to factory spec and retune rather than trying to get it exactly as it is after you’ve had the bow for a year or two.
First thing is first. Buy a good set of strings and cables! There are many good string makers out there that can provide you with a good, stable set of strings. I am not mentioning names as this article is not meant to sell a product.
The first thing you need to do is take measurements off of your bow with the old strings. Axle to axle length, brace height and draw weight. Also, make note of where your timing marks are currently. Keep in mind this is only for reference. Chances are, your bow as it sits now has some measurement out of whack. Most manufacturers, including Bowtech have a +- of .25” with specs.
Before touching anything, it’s a good idea to take a few digital pictures of the bow, particularly the cams. This will serve as a reference as to how the strings and cables are routed around the cams. I also like to take a pic of how the cables cross below the cable guard.
Put your bow in a press and relieve tension from the strings and cables. Remove the modules from the cams as it makes it easier to get the old set off and the new on.
I pre measure the new strings and cables before I ever put them on the bow. AMO specs say to measure string and cable lengths under 100lbs of tension from the end of one loop to the end of the other using a ¼” post. I have a 2x4 that has a ¼” post on one end. I then measure from the far side of the post to the exact length the new cable must be and make a mark on the 2x4. I then take my digital bow scale, the one I use to check draw weight and hook one end of the loop on it and the other loop on the post of the 2x4. Pull tight until you reach 100lbs of tension and see if your cable is the length pre-measured on the board. If it’s too long, add twists until you get the correct length under tension. If you don’t have a scale, that’s OK, just pull as hard as you can and take the measurement.
Once this is done, put the new cable on the bow, being careful to not add or remove twists from the cable. Now, move on to the next cable and do the same thing.
For the string, do the same thing. When I take the old string off, I put it on my measuring board and measure the distance each set of speed nocks are from the ends so that I can put the new speed nocks on in the exact same place the old ones were. Then, measure the new string and make adjustments to length as needed and put it on the bow.
Put your modules back in the cams and ensure that everything is exactly the way you took the old set off. Install your cable slide as well.
Relieve tension the press being careful that the new strings and cables seat in the cams correctly. Now is the time to put your nocking point or string loop on and square it with the arrow rest. If you use a drop away and it is tied to your downward stroking cable DO NOT set it up at this point. Measure axle to axle and brace height. They should be right on spec at this point. Pull the bow back a couple of times to really seat the strings.
Now, the most important thing is to get your bow to reach max poundage and the correct draw length. Bottom out your limb bolts to max the bow out and then using a scale, check your poundage. If you have a draw board, use it to check your draw length. If you don’t, draw your bow with an arrow and have a friend measure the arrow at the point where the deepest part of the grip and the arrow intersect.
If your draw weight is low, at equal half twists at a time to both cables until draw weight is restored to maximum. Double check your draw length. Keep in mind that adding twists to your cables will lengthen draw length and removing will shorten.
At this point, you’re bow should be very close to specs. Now you can move on to cam synch and timing.
The idea here is to have both draw stops on the cam modules hitting the cables at the exact same time. If you have a draw board, use it. If not, use a ceiling or wall mounted hook to slowly draw the bow down. It helps to be at eye level with the cams when the bow is drawn. Watch the cams break over and hit the stops. You want them to JUST touch the cable, not push the cables toward the bow. If one cam is touching before the other, add a half twist at a time to that cam until they are both in JUST touching. It also helps to slide the draw stop peg out of the way when doing this. Once this is accomplished, draw the bow and have a friend slide the draw stop tight to the limb, compressing the o-ring on the stop peg. Now, you can further fine tune this adding equal twists to both cables to pull the draw stops about 1/16” or 1/8” of inche from touching the cables at full draw. The idea here is that the o-ring will compress and account for the final 1/16 to 1/8 inch of travel and land the two draw stops on the cable slightly. This will also restore you to 80% letoff.
Now you can setup your drop away rest and go shoot the bow for a while to settle the strings in. Once you do this, recheck timing. It might have moved a bit and you need to further fine tune it. It is recommended to install the drop away pull cord as far down as possible on the cable to limit the distorting that happens. This distortion throws the bottom cam out of synch by creating a “shortening” effect of the cable. Once this is done, your bow should be in spec, 80% letoff, max poundage, correct draw length, and synched cams.
Put your peep in and adjust its rotation as necessary and shoot away.
Credit to Dave Nowlin on AT for a lot of this. He’s a binary guru and helped me out tremendously getting my bow setup the correctly the first time.
01-26-2009, 12:20 PM
#3
Nontypical Buck
Thread Starter
Join Date: Feb 2003
Location: Central PA
Posts: 2,299
RE: New strings on Allegiance.....just an FYI
Yup, he is. After not being able to hit my spec, I PM'd him and he gave me a call and explained things to me. I pulled everything back off the bow and started from square one again. Made all the difference in the world and much, much easier.
01-26-2009, 08:05 PM
#6
Typical Buck
Join Date: Dec 2006
Location:
Posts: 654
RE: New strings on Allegiance.....just an FYI
I'm always here reading and don't post too much but I have to say this is one of the best threads I've read in a long time. You done good! I've got this one stuck in my favorite's now. Thanks!!
Dan/Vars(my tracking machine)
Dan/Vars(my tracking machine)
01-27-2009, 04:56 AM
#7
Nontypical Buck
Thread Starter
Join Date: Feb 2003
Location: Central PA
Posts: 2,299
RE: New strings on Allegiance.....just an FYI
Thanks guys. I enjoyed writing it up. I'm by no means an expert, but I really thought it would be nice to pass this experience off to anyone that can use it here.
01-28-2009, 04:45 AM
#9
Nontypical Buck
Thread Starter
Join Date: Feb 2003
Location: Central PA
Posts: 2,299
RE: New strings on Allegiance.....just an FYI
Thanks for the compliments guys. My next venture is to get a hold of a chrono and start playing with optimum cam rotation settings to see what I can find out.
On another note. One thing I failed to mention in my original post is regarding setting the cam synch. If you don't have a draw board and are pulling from say a hook on the ceiling or wall, make absolutely certain that you are putting the pressure on the grip of the bow, where your hand would normally be. I noticed this the other night when I was playing around with mine on a ceiling hook. If you grasp the riser on both sides and pull down, you'll put different pressure on each limb and give a false reading on cam timing. By pulling down with all the pressure on the grip, as you would when drawing the bow, you'll get a better reading.
Also, after you've put a few hundred shots through the bow after setting this all up, go back and double check everything. It may or may not change slightly due to the system settling in further.
On another note. One thing I failed to mention in my original post is regarding setting the cam synch. If you don't have a draw board and are pulling from say a hook on the ceiling or wall, make absolutely certain that you are putting the pressure on the grip of the bow, where your hand would normally be. I noticed this the other night when I was playing around with mine on a ceiling hook. If you grasp the riser on both sides and pull down, you'll put different pressure on each limb and give a false reading on cam timing. By pulling down with all the pressure on the grip, as you would when drawing the bow, you'll get a better reading.
Also, after you've put a few hundred shots through the bow after setting this all up, go back and double check everything. It may or may not change slightly due to the system settling in further.