Mathews v3x 33 Tuning Issues

[Kmarkwardt]

I know theres another thread with the same title, and I read through that, but I don't believe his issue is my issue.

FWIW, I'm a relatively new "do it yourself" tuner, but I've been able to tune the last 3 bows I've had without too many issues.

Bow is a v3x 33", hamskea epsilon rest.

I had it all tuned and shooting broadheads well for spring bear using:

30" Easton Axis 300 spine w/ 14g HIT insert, 25 grain collar and 125 grain broadhead. I realize that that seems under-spined, but it shot great for me in the spring. (and as I'll mention later, I tried the 260 spine with the same setup and got the same tear).

I just got the strings replaced.

Shot in a bit (50 or so), then went to tune.

At centershot I get a 4" nock right tear. I can get it to bullethole, but only if I move the rest away from the riser by a ton. Centershot is 13"/16" and I'm at like 1 1/8" away from the riser.

I tried dropping the point weight down to 125g, and I also tried the exact same setup arrow with a 260 spine instead. Same exact tear.

I tried bareshaft with the 300 spine, same tear.

I tried bareshaft with 260 spine, same tear.

Tried a smaller nock to make sure it wasn't pinching, same tear.

Tried shooting differently, same tear.

Is my next step to adjust top hats?

Is it weird that new strings would change a bow enough to have to do this?

 

[S.Clancy]

Did you measure the strings/cables and make sure they were spec length?

 

[feanor]

What was the arrow flight doing when you shot the 50? Assuming the rest was same position as it was with old string?

 

[feanor]

I chased my tail on the 33 trying to get perfect paper tuning etc, but just wound up shooting with broadheads and getting consistent flight with close to factory specs on rest.

 

[gelton]

IME - it's always best to start with the top hats and then fine-tune with the rest. You might also want to check it on a drawboard to be sure that the cables have the correct twist and that your draw stops are hitting at the same time. But yeah, every time I change strings, even with the exact same brand I have to retune.

 

[Kmarkwardt]

Did you measure the strings/cables and make sure they were spec length?

I did not. I didn’t install the strings.

 

[Kmarkwardt]

What was the arrow flight doing when you shot the 50? Assuming the rest was same position as it was with old string?

Didn’t tune, just shot. Grouped well though.

 

[Kmarkwardt]

I chased my tail on the 33 trying to get perfect paper tuning etc, but just wound up shooting with broadheads and getting consistent flight with close to factory specs on rest.

Yeah, tried that. Didn’t work for me.

 

[Kmarkwardt]

I chased my tail on the 33 trying to get perfect paper tuning etc, but just wound up shooting with broadheads and getting consistent flight with close to factory specs on rest.

Yeah, tried that. Didn’t work for me

IME - it's always best to start with the top hats and then fine-tune with the rest. You might also want to check it on a drawboard to be sure that the cables have the correct twist and that your draw stops are hitting at the same time. But yeah, every time I change strings, even with the exact same brand I have to retune.

yeah. In my limited experience, I’ve come to believe that getting everything shooting well with the rest at center shot, then small fine tuning if necessary.

 

[Kmarkwardt]

Just measured brace height. If I’m doing it right (deepest part of the grip to string), it’s at 6 3/8” and I believe it should be 6 1/2”.

Problem?

 

[Billy Goat]

Just measured brace height. If I’m doing it right (deepest part of the grip to string), it’s at 6 3/8” and I believe it should be 6 1/2”.

Problem?

Check the rest of the specs, like ATA, where are the cables at in the timing windows?

The donuts on the yoke, how are they positioned relative to the string?


You are going to want to set your rest at 13/16", check to make sure you are getting vane clearance on the roller guard, rotate your vane position to get clearance need be. Make course adjustments with the top hats, once close fine tune by micro adjusting the rest.

 

[Zac]

I'd start by flipping one of your thicker top hats to the right, then the next.

 

[S.Clancy]

I did not. I didn’t install the strings.

Just measured brace height. If I’m doing it right (deepest part of the grip to string), it’s at 6 3/8” and I believe it should be 6 1/2”.

Problem?

IMO something is off in your string set. Generally, when I swap strings out (I have a press and do it myself) I first measure them to see if they are in spec. I have seen them arrive out of spec, if that happens let the string maker know, they will send a new set if they are good.

If I put good strings on (everything else being set to the previous strings) the tuning takes almost no time, maybe a few minor adjustments. If you put new strings on and all of a sudden the bow is way out of wack, I would blame the new strings.

 

[Colobwhntr]

The last 2 times I’ve replaced strings on my Mathew’s I’ve had to adjust top hats. Not sure why but I’d get a crazy tear and move my top hats and it’d clear it up.

 

[Brandon.miller.4]

Literally had the exact same issues you described. I swapped my top hats around it fixed everything. Got bullet holes immediately. Give that a shot.

 

[Kmarkwardt]

The last 2 times I’ve replaced strings on my Mathew’s I’ve had to adjust top hats. Not sure why but I’d get a crazy tear and move my top hats and it’d clear it up.

Literally had the exact same issues you described. I swapped my top hats around it fixed everything. Got bullet holes immediately. Give that a shot.

That's the plan for tomorrow.

So, related question, if I carry my old strings around as backups and have to swap them using the SAS system, does that mean I'll likely need to adjust top hats again?

 

[Billy Goat]

That's the plan for tomorrow.

So, related question, if I carry my old strings around as backups and have to swap them using the SAS system, does that mean I'll likely need to adjust top hats again?

You can swap the string without issue, it's the changing position on the yoke donut that causes the change in cam lean.

That donut/yoke splitter is supposed to sit perpendicular to the string, which results in the cable not coming off of it centered. But it's about impossible to get the exact same placement putting the cables back on it anyways. So it's very common to need to change the top hats after changing cables out. Can move the cable around on the donut as a trial and error until you get it, but it's easier to just swap top hats, unless that's not an option.

 

[Kmarkwardt]

So I don’t have a vice, but a friend who was a previous bow-tech does. But he can’t get to it for a few days.

Am I asking for trouble if I try and flip the top hats myself using the SAS system?

 

[Kmarkwardt]

Nvm. The sas wouldn’t relieve tension on both cables and strings, which I believe I’d need to have.

 

[Billy Goat]

So I don’t have a vice, but a friend who was a previous bow-tech does. But he can’t get to it for a few days.

Am I asking for trouble if I try and flip the top hats myself using the SAS system?

A vice won't help.

You need a press, and one for parallel limbs.

That might be what you meant tho.