# problems paper tuning.



## smesk403 (Dec 12, 2006)

was in the shop last night and was tuning a bow for someone and after spending a hour or so getting rid of the right tear I started playing with the nocking point. 

right at 90 or maybe 1/16" nock high I was getting close to a 3" tear.

long story short after much time it finally paper tuned bullet holes however it was set near 1/2" nock high. I checked all the specs-good, timing-good, rest-good, even tried using a coupe different releases and adding a D-loop. nothing helped. I asked the 2 other guys workin in the shop and between the 3 of us we were stumped. 

I'm sure there's somene on here who's got an answer for me.


----------



## panthru (Jun 23, 2006)

sounds to me like one side of the yoke needs a few twists. then it should bring your centershot back out also. :wink:


----------



## smesk403 (Dec 12, 2006)

panthru said:


> sounds to me like one side of the yoke needs a few twists. then it should bring your centershot back out also. :wink:


added probably 4 twists to the right side yoke. this got rid of the right tear. the nock point is still waaaaayyy off. any other ideas guys?


----------



## OHIOBUCK (Oct 25, 2006)

smesk403 said:


> added probably 4 twists to the right side yoke. this got rid of the right tear. the nock point is still waaaaayyy off. any other ideas guys?


You shure your not getting contact somewhere?

Where is the rest height centered at?


----------



## panthru (Jun 23, 2006)

what kind of bow/arrow???? did it tear like this with other arrows or just one??


----------



## smesk403 (Dec 12, 2006)

thanks guys keep it comin

bow is a drenalin using easton axis 400's. 27" draw set at 67lbs. the rest was sitting at 43/64" from riser to center of arrow shaft. rest height is sitting at 1 1/8" up off the shelf to shaft center. running right through the burger hole or just a smidge up. I played with the rest last night adjusting the height on the rest as well and nothing seemed to work. 

The customer stated that he had just had some warranty work done and had new limbs put on at a different shop. He said the bow came off the cam when he was checking it for poundage and thus blew up on him. He said the limbs and string and cable all were replaced. 

I checked the cam and Idler to see if they were bent at all or anything. both looked good. not sure if there is any way to check the riser (not that the riser can really bend)

he said it wasn't shooting well and he brought it back to us (where he originally bought it from). it was quite clear that whoever did the warranty work and rebuilt this bow didn't know a thing. Last night the timing was off nearly 3/16" and the specs were all messed up (ata nearly 1/2" long and BH almost 1/4" short. and the idler had some crazy lean (hence putting in 4 twists.) after getting everthing back to spec I set it up from scratch the way I would initially set up any other drenalin or other mathews bow for that matter. 

set it to where I usually go as a starting point and we were getting about a 3" tear.

Like I said I worked on it last night for nearly 2 hours and with no clear answer we kept the bow and am going back to work on it tomorrow. just looking for new ideas to try. 

Oh yeah, customer said it also chrono'd a lot slower then before the warranty work was done. Customer said it had chrono'd at 274fps. I chrono'd it last night at 260fps. 
Then I chron'd a new drenalin off the shelf. all same specs and same poundage. both bows had bare strings with only 2 nocks and peep. the new drenalin chrono'd his arrows at 275fps.

Hope this can help someone give me an answer so we can do this customer right. I am not the shop manager but if we can't figure it out soon we'll probably just send it off to mathews to have them take a look. 

I know my stuff about tuning bows but I know that there's plenty plenty more to learn so I figured someone on here might have some input.


----------



## smesk403 (Dec 12, 2006)

panthru said:


> what kind of bow/arrow???? did it tear like this with other arrows or just one??


guess It didn't check it against other arrows in the shop but I did weigh his arrows and they all weighed within 2 grains of each other. 

Also tried shooting cock vane up, down, and out. still got same tear

checked for clearance issues and couldn't find any.


----------



## McAllister (Jan 25, 2003)

I am assuming the paper tear is low thats why you have the knock 1/2" high? If this is the case and all other things have been check/varified as not being a problem. The bows is to spec and there is no fletch contact. Start with a weaker arrow, either a longer 400 or go to a 500 spine, but start with an arrow long enough so that it is weak! Shoot through paper at 9' or so and start cuting the arrow down until you get the vertical tear you are looking for. Tune the Arrow to the Bow and the Shooter!!!

Good luck!


----------



## NMP (Aug 6, 2003)

I would probably check the deflection numbers on the limbs from here. They may have just replaced the one limb at the shop and the bottom could now be significantly stiffer than the top. This will cause a severe nock low tear. I have a bow that this happened to.


----------



## OHIOBUCK (Oct 25, 2006)

smesk403 said:


> thanks guys keep it comin
> 
> bow is a drenalin using easton axis 400's. 27" draw set at 67lbs. the rest was sitting at 43/64" from riser to center of arrow shaft. rest height is sitting at 1 1/8" up off the shelf to shaft center. running right through the burger hole or just a smidge up. I played with the rest last night adjusting the height on the rest as well and nothing seemed to work.
> 
> ...


15 fps loss is a lot. Something is deff wrong. Maybe the axle's are slightly bent causing a little drag...............bad bearing maybe.

Limbs were changed..........mismatched limbs maybe. (reverse the limbs and see if the tear goes the other way.)

I'm just throwing some stuff at you.........Let us know if you find the prob.

Good luck.


----------



## firefalls (Jan 27, 2008)

Had the same thing drive me nuts for a while. All the specs were as close as I could get them. Could have used McAllister's post a while ago. Turned out that after I tried everything else I went with a longer arrow and the low tear vanished. Sometimes longer is better.


----------



## bigbuckdn (Sep 19, 2007)

had the same problem with a stiff arrow and a dropaway rest it just tuned knock low but it was realy to stiff confused me for awhile but it was the arrow


----------



## smesk403 (Dec 12, 2006)

NMP said:


> I would probably check the deflection numbers on the limbs from here. They may have just replaced the one limb at the shop and the bottom could now be significantly stiffer than the top. This will cause a severe nock low tear. I have a bow that this happened to.


very interesting. never thought of that. How can I go about chekcing the deflection numbers on the limbs. please explain.


----------



## smesk403 (Dec 12, 2006)

OHIOBUCK said:


> 15 fps loss is a lot. Something is deff wrong. Maybe the axle's are slightly bent causing a little drag...............bad bearing maybe.
> 
> Limbs were changed..........mismatched limbs maybe. (reverse the limbs and see if the tear goes the other way.)
> 
> ...



I also will try switching the limbs and seeing if the problem reverses. when I do that I'll check the axles and bearings. 



**thanks guys for the help. this is what AT is about


----------



## NMP (Aug 6, 2003)

smesk403 said:


> very interesting. never thought of that. How can I go about chekcing the deflection numbers on the limbs. please explain.


The numbers will be visible on the bottom side of the limbs in the limb pocket area. Between the limb and the pocket or riser. You may need to remove them from the bow to see the numbers. They should be very close if not the same on both limbs.


----------



## BuckBrush (Jun 13, 2008)

I'm curious about the changing limbs. Did it reverse the tear? Let us know. It makes sense, I never would have thought of that. Had that problem once, scrapped the bow.


----------



## fletched (May 10, 2006)

If you are using a drop away then what happens is that you are getting some arrow bounce which will make you have to set the rest nock high. If you raised the nocking point, then that can slow your bow down. Keep the nocking point either straight out from the rest holes or a little lower. Then lower the rest if it needs adjusting. The closer you can get your nock or loop to the center of the string, measured ata, the faster the bow will be. When you shoot with a release, the flex of an arrow is up and down. When you use most drop away rest, at full draw they are in the upright position and are hard having no spring or give to them. Once you release the arrow, the up and down flex can't push the rest down so instead, it will jump up a little. By tuning the rest nock high, it will cancel the bounce. When an arrow is sitting on the rest, it will look out of place but will be fine. 
Make sure your nocking point is centered to the rest holes with the arrow 90 degree to the string before you lower your rest. This will put the nocking point in prime position. Then if you have to lower the rest to make it tune, you won't be loosing any speed.


----------



## smesk403 (Dec 12, 2006)

BuckBrush said:


> I'm curious about the changing limbs. Did it reverse the tear? Let us know. It makes sense, I never would have thought of that. Had that problem once, scrapped the bow.



didn't get to it today. had a busy day. hopefull tomorrow and I'll keep everyone posted.


----------



## xr650rRider (May 27, 2007)

Wondering if you made in progress with the Drenalin.

I've had a very similiar thing going on and have been following this thread. 
My son has a Drenalin with 29-1/2" draw length, 62 lb. draw weight (70 lb limbs backed out 4 turns) , shooting Gold Tip Entrada Ultralight arrows. They are cut 28-1/2" with 100 grain tips. He is using a whisker biscuit. One month ago this combination was shooting bullet holes. The nocks on the Gold tip arrows are red in color. Strings on the bow are factory Zebra Barracuda's. In the last couple of weeks he has broken 5 of the red nocks and it finally culminated in string jumping off the cam and cutting both end servings. Each time the arrow has made it to the target, so not a completed dry fire. I re-served the string with Halo .014 serving while putting the string under approximately 200 lbs of tension. I then re-served the cable where it had started seperating as well. I changed the nocks out to pin nocks and there have been no more broken nocks. Replaced strings and cable and set idler lean on the money with about 1/8" seperation between an arrow placed on the left side of the idler and the nock point on the string, idler is straight at full draw. The cam timing was right on and ATA was 33" on the money.
Setting the nock point level resulted in a 2" high and 1-1/2" left tear. Raising the rest or in effect lowering the nock point, made it worse. Finally had the lower the rest until the arrow was pointing down at a severe angle. The nock point was over 1/2" high, closer to 3/4" high. This still resulted in a slight high tear and would never cut it shooting broadheads. (I think whisker biscuit adjustments require the opposite adjustment that is mentioned for other arrow rests at least for high/low tears.) 

With all these problems happening, I was convinced that something was bent. Completely dis-assembled the bow, idler perfect. Cam did not appear to be bent, but was cocked a little in the limb. Not severe enough to cause tracking problems. Bearings good, bushing good, axles not bent. Completely inspect limbs and find nothing. Limb turrets look fine. Put it all back together and it still shoots the same. Find this thread and the mention of imbalanced limbs, so chase that wild goose. Reverse all the hardware and put limbs reversed back on bow. Still shoots the same. Put another string and cable set on the bow (I had 3 sets). Put bow back into specs and it shoots the same. About this point I've about decided to use it as a baseball bat and a 4" square tubing post as the ball. Decided against that and compared the stripped down riser to another Drenalin as I thought it might be tweaked slightly. Actually compared it to 2 other Drenalins and if this one is bent then so are they. 
The other arrows that he has but doesn't usually shoot are 29" Gold Tip expedition hunters 7595's with 125 grain tips. By the OnTarget2 software these are too stiff at 62# draw weight. We have tried one of them off an on during the shooting sessions. They had also shot bullet holes when the bow was first setup. They still shot the same as the other arrows. Finally set the rest back with an arrow centered in the Berger hole, 11/16" out from the riser for centershot and about 1/8" high. Now the rest has been in this position at least 300 times. Shot it and the tears are the same. Reach over and get one of my arrows which are 300 spine GoldTip ultralight pros at 31" with 125 grain tips and shot a bullet hole. Tried some of my 7595 Goldtip Hunters cut to 29-1/2"
with 125 grain tips and some of the high tear came back. Switched to 100 grain tips and it shot bullet holes. Tried his Expedition hunter with 100 grain tip and it still shot high left. Picked up another Expedition and shot it with 100 grain tip and shot bullet holes. 

So I'm assuming that the Entrada ultralights have changed spine since he first started shooting them. The one Expedition hunter that we were using testing exhibited the exact same behavior. At least the bow is shooting good again but it has been a trial. 
All the tests were on paper from 6-12 ft. Tried bare Entrada shafts as well. Tear was more severe. Chronographing the bow during most of the tests and it was still shooting 300 fps cranked to 70lbs with the Entradas and 280 fps backed off to 62 lbs. About 4 fps loss using the other arrows.

Anyone have anything else to add. Are the stiffer spined arrows covering up a problem that still exists? The only thing I didn't change was the cam. I even put a different whisker biscuit on it at one point.


----------



## McAllister (Jan 25, 2003)

I think you are on the right track! I think if you could put your arrows on a SPINE tester you would find that the 31" (GoldTip ultralight pros) arrow is weaker than you think! Archer's Advantage is telling me that the 28.5" arrow (Gold Tip Entrada Ultralight) is the stiffer one out of the bunch. Did you shoot this arrow at 70#?? Once you get the tear close, get out and group tune! And don't be afraid to adjust the poundage up or down to find the right spine and arrow mass weight to draw weight. 300 fps is smoking with an arrow that long!

Good luck!


----------



## xr650rRider (May 27, 2007)

Your probably looking at a 400 spine Ultralight pro.

The 300 Goldtip Ultralight pros is what I shoot out of my Switchback LD with 32.25" draw length. With 125 grain tips I get 278 fps and can shoot bareshaft bullet holes at 20 feet. Now with Blazer vanes thru the whisker biscuit I actually have to adjust slightly from the bareshaft. Anyway I think they are spined pretty good. A 340 or 400 is too weak for my bow.

The Drenalin on the other hand according to the software was supposed to be spined perfect at 62 lbs with a 400 spine arrow and 100 grain tips. This is of course adjusting the software for actual velocity from the chronograph. Ever bow I've chronographed has to be reduced at least 10 fps IBO in the software. At 70 lbs the Entrada is getting very close to being too light for the draw weight. Its right at 5 grains/lb. The Drenalin shot bullet holes when the arrows were new, so I'm having a hard time buying that they've changed that much having only been shot maybe 50 times each at the most. But the shots thru the paper don't lie. My son has yet to shoot it, so his results might be slightly different than mine. He always gets a left tear when I'm shooting bullet holes. But the high tears were pretty consistent. I have a 32" draw length so its difficult to shoot a 29-1/2" bow without possibly pulling at a bad angle on the string.


----------



## smesk403 (Dec 12, 2006)

sorry haven't been back on this post for a few days. I guess the customer came and picked up the bow on my days off. guess he was fed up and was going to trade for something else. sounds like others that have been following the thread have similar problems though so keep the advice coming.


----------



## McAllister (Jan 25, 2003)

I had compared all the arrow at 300 spine. You did not mention on the first post the 28.5" arrow was a 400 spine. I assumed 300. AA tells me that a 400 spine is way weak for your son's setup. So your 300 spine arrow at 31" is stiffer. I find solocams and cam 1/2's to be very spine specific for me, But when I find the right combination of spine, arrow mass weight and draw weight they are deadly. It just seems to take more time playing then it does with a true dual cam bow. 

Most likley your son's hand is a little different then yours and it causes him to torque the bow/stabilizer to the left and that's were the left tear is coming from. I to have issues with left tears depending on the bow design. Anyway your on the right track. I'm sure its arrow spine, but why it worked and then it didn't I don't know??

Good luck!


----------



## xr650rRider (May 27, 2007)

This is what OnTarget2 shows.


----------



## McAllister (Jan 25, 2003)

I don't know how to cut and past or print my AA screen to a file., But its saying Marginal weak. That is the result you are seeing with the high tear. If you can tell me how to get a copy of AA into Archery Talk I will give it a shot.


----------



## xr650rRider (May 27, 2007)

I use SnagIT to capture the screen, then I use a program I wrote years ago to reduce the size of the .jpg image.

You can do a screen capture by hitting "Ctrl" "Print Screen" at the same time. This copies a Windows bitmap image to the clipboard. Then open Windows Paint program and press "Ctrl" and "V" simultaneously. Then you can save it as a JPEG image. But you have to use another program to resize the image so that it isn't larger than 122 KB. IrfanView used to be a very good free program for doing all of the above other than the screen capture. There are other power tool downloads for XP that allow you to easily resize an image. You need something that actually reduces the pixel count not just resizing the image by compression.

When your editing a message on this board the paper clip symbol is where you insert an attachment. Just upload the image you've resized.


----------

