View Full Version : New string/cables
08-11-2010, 03:23 PM
I just installed a new string and cables from H&M on my '09 Firecat. My ATA was a good 1/4 long, so I started twisting up the cables. Now the cables are "lumpy" for lack of a better term. Looks like alot of loose strands or unevenly stretched strands. I'm still at least 1/8 inch off on ATA. Should I keep twisting to get to the right ATA, and everything will stretch in as I start shooting, or what? First time I"ve seen this happen before. Any ideas or help is appreciated!
08-11-2010, 08:32 PM
I'd place a call to H&M and ask them. Normally you shouldn't have to twist new strings at all, excpet maybe a twist or two to align the peep or sync the cams.
Have you given a thought to the idea that by twisting both the string and cables you can decrease the A2A? Just what is the A2A measurement? It should be ABOUT 32 1/4", but even 32 1/2 is acceptable. Frankly I don't get too anal about 1/4". If the brace height is close, A2A close, and the draw weight I want to shoot is achievable then I just tune the bow and shoot it.
The main thing to do is, once you have the bow tuned and shooting to your liking, then you measure everything for future reference. Specs are just close approximations of where the factory says the bow shoots best, but each bow can be just slightly diferent. Get yours close and by playing around you can find the specs your particular bow likes.
08-11-2010, 10:22 PM
by twisting both the string and cables you can decrease the A2A?
If you don't twist both the Draw length is altered.
My recommendation for the importance of the bow specs for a particular model in order of importance.
1. Draw length. The most important of all, get this wrong and you won't shoot the bow well.
2. Draw weight. Still very important, affects speed and the ability to draw smoothly for accuracy.
3. Brace height. Not as important but does effect power stroke therefore speed. Too low a brace height can effect accuracy too.
4. Axle to Axle. Not important at all if the other three are within spec. Has no real bearing on speed or accuracy.
The first two are the most important. As long as they are right, it doesn't matter if your ata is out by 1/2". :)
08-12-2010, 02:56 AM
The first thing I did was send an e-mail to H&M, as they were already closed for the day. I just thought that one of you archery gurus might have had this happen. One thing I don't understand though is, when I first got this bow I was told by everyone to read the threads on AT about cam tuning, etc. The original cables took 15 twists each to get the bow to published specs, as recommended by the thread on AT. (32 1/4 ATA) Now you guys are saying ATA isn't important????
08-12-2010, 05:20 AM
IMO the strings and cables should be as close to factory specks as possible with the least amount of twist as possible. your strings are more than likely way to long. the more you have to twist them the more trouble you will have with your peep . if they aren't at factory specks the bow will be out of time and very noisie . in the past i seem to have trouble tunning my bows when i ordered new strings,so i built my own string jig and make my own . in my oppinion it is best for the person that makes the strings be the one to put them on and tune the bow. to get your strings and cables right you need to check them under 90#s of tention they need to be at factory specks. if you do this your brace ht. , ata, and the bows peak wt. will be correct. if they are way to long they want work.
08-12-2010, 06:18 AM
I was told by everyone to read the threads on AT about cam tuning, etc.
Not by everyone but its still good advice. In order to learn how to maintain your bow you need to study up. The more you read, the more you learn.
The original cables took 15 twists each to get the bow to published specs
Then the new cables must be longer if the string length is the same. Put as many twists as needed. What was the original cable length? It can be shorter than the recommended spec. Differences in manufacture mean there is no exact spec, its just a guide.
Now you guys are saying ATA isn't important????
I'm saying that exactly. If your DL is correct and your DW is correct and your BH is correct, why is ATA that important?
08-12-2010, 12:15 PM
After reading all the threads on AT about Cat cam tuning, I had my old set up shooting great. Cable gap was roughly 1/16th of an inch, ATA was 32 1/4, and BH was 7. Exactly what specs call for. Old string was 54 1/2, cables were 39 according to data sheet. I never physically measured them though. I did measure the new string and cables, and they were to spec. Once installed, my ATA is 32 1/2, and BH is 6 7/8. The cable gap is roughly 1/4 now. Twisting the new cables 5 turns each only changed my ATA by 1/8 at most. Any more twists than that, and I started getting the bulges in the cables. I'm just trying to get the most out of my bow that I can, following the AT posts on CAT cam tuning. Any suggestions?
08-13-2010, 04:30 AM
I did measure the new string and cables, and they were to spec.
Were they to spec with twists already in them? The custom string makers put twists into string before doing the center serving these days, a trend imho. Do Martin's spec include the length with twists in them? I don't think so. I think thats where the difference is.
My recommendation is to put as many twists as need, even if they are bunching up. Won't hurt. :)
08-13-2010, 01:25 PM
Yes, to spec with the amount of twist H&M sent them to me with. I talked to Mike at H&M, he said go ahead and twist them if neccessary to get my ATA correct. Any bulges should shoot out after a few sessions. If not, he'd make up some new ones. Well, I got my ATA back to 32 1/4, went outside to shoot. At full draw, the cams over rotated and locked the bow up. The draw length did appear to be right. Had to use a press to let it down. The cable gap on the cams is right at 1/4 inch. The gap with the old cables was 1/16th. Now I'm trying to figure out what the heck went wrong. If anyone has any ideas, please let me know! Thanks all!
First off, I'm no tech tuning gura... but have a question.. Are you checking your specs with the limb bolts all the way in? I've read many times that this is the way to do it.
08-13-2010, 03:01 PM
If it locked up - the draw stop is not in the right place.
If you twist/untwist the cables and string to the factory spec - your ATA and BH should be right on or only a hair off. And specs are with the limb bolts bottomed out.
Also - string length is measured with tension on them - 90-100 lbs.
If you measure without any tension on them - they need to be about 1/4" short.
08-13-2010, 03:22 PM
As a string builder I usually build my strings a 1/4 inch over specs.
Then pre-stretch them
Then twist to specs and serve them.
Then stretch them again.
Most of the time the bows I install them on come out with the right ata, brace height, poundage.
But my bow had to be different it was a 1/4 inch shorter, but all other specs where correct.
Checking my original string it cam out the same 1/4 inch shorter
Most of the guys on here will tell you the same ata within reason shouldn't matter
twist it and shoot it!
08-13-2010, 06:27 PM
Me thinks it's maybe time for you to post some pictures of everything. For starters, you do have a draw stop installed on the cam, right? If you do then it's set way too long. The whole idea of a draw stop is to fine tune the draw length. If it's not on the cam then it will allow you to draw too far and lock the bow up at full draw, just as you have experienced.
08-13-2010, 10:59 PM
Yes, to spec with the amount of twist H&M sent them to me with.
So the new string would be same? You probably need to put more twists into the string too. That's why we mentioned twisting both cables and string to get you ATA down. Its a combination of the two.
To measure your draw length, place an arrow on the string and draw back then have some one mark the arrow at the rest hole in the riser, then add 1 3/4" and you will have the AMO draw length. Be careful when doing it this way.
08-14-2010, 09:16 AM
My draw stop was still in the same position (28 1/2 inch draw) as with the old string and cable. The limbs were bottomed out when I measured everything. Now, I noticed a crack in the upper limb, so nothing I can do until I get new limbs. Talked to Joel, and he's sending them out. Hope they come quick. Season starts here Oct. 1st. Thanks again for the help guys. I'll try to post some pics when the new limbs get in and on. If not, looks like it's time to break out the Moab again. lol
08-17-2010, 03:31 AM
Ok. I finally figured out what happened. When I put the new strings on, I had apparently gotten the cables crossed in the roller guard. outside cable on the inside, etc. Apparently, I had the cams wound tight enough before that this was just enough extra to lock it up. It's all back and shooting again now. New strings seem to be great. The previouosly mentioned bulges didn't even have to be shot out. About 5 minutes with the bow setting at 68#, and they smoothed right out. Anyway, thanks to all who replied, and if you wantto know anything else about what happened, drop me a line!
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