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hunt123
04-15-2011, 09:36 AM
Just started setting up my Pantera (new, 2010 model) yesterday. Found a couple dismaying things:

1) Can't completely tear down without a press any longer. Liked that feature on my Bengal. So now I have to get a press. Called Joel about it and he said there's more pre-load on the Pantera.

2) The back wall is real spongy. Only one way to fix it and it's not the best solution.
I put in the #6 DL mod and on my drawboard, it measures to 31.25". BUT when I actually draw it, from 30.375" to 31.25" is real spongy. Almost a full inch of sponge. So I have to set my draw stop at 30.375" to eliminate it and have a good firm backwall.

Technically the bow allows me to shoot a 31" DL, but only IF I want to put up with sponginess. The Bengal wasn't that way. It had the M2-Pro cam and not one bit of sponginess all the way back to 31+.

Same thing happened with the #5 mod. I had it in and there was almost a full inch of sponge with that one also.

The Pantera has the AccuTrak cam and I'm thinking it's something about that cam that's doing it. Has anyone here had that problem? Is there any solution other than what I've done?

Per my other post re: cam rotation, ATA and brace height are correct.

archerx7
04-15-2011, 05:35 PM
Sounds like something is off, I setup a Pantera last year for a guy who was a 31" DL and the wall on that bow wasn't the least but spongy. It's possible that you may need to either take some twists out of the string or put some in the cable or maybe a little of both so you get some more rotation on the cam and can set the stop before the cable runs out of track on the mod. The #6 mod should give you a solid wall at 31.25".

hunt123
04-16-2011, 03:58 AM
Sounds like something is off, I setup a Pantera last year for a guy who was a 31" DL and the wall on that bow wasn't the least but spongy. It's possible that you may need to either take some twists out of the string or put some in the cable or maybe a little of both so you get some more rotation on the cam and can set the stop before the cable runs out of track on the mod. The #6 mod should give you a solid wall at 31.25".

So are the factory ATA and brace height specs only a general mark to shoot for? I imagine they'll go off, maybe by quite a bit if I do that. I don't have a problem doing it, the cam looked way under-rotated to me anyhow. I just want to make sure it won't cause any kind of problem.

Second question:
I don't have a real clear idea on the relationship between twisting/untwisting the string and doing the same thing on the cable.

Twisting the string = ??
Untwisting the string = ??

Twisting the cable = ??
Untwisting the cable = ??

How do you know when to do which?
How do you know when to do both?

Sorry for the greenhorn question, I've learned a lot since I started but that's one thing that's still stumping me.

archerx7
04-16-2011, 04:51 AM
So are the factory ATA and brace height specs only a general mark to shoot for? I imagine they'll go off, maybe by quite a bit if I do that. I don't have a problem doing it, the cam looked way under-rotated to me anyhow. I just want to make sure it won't cause any kind of problem.

Second question:
I don't have a real clear idea on the relationship between twisting/untwisting the string and doing the same thing on the cable.

Twisting the string = ??
Untwisting the string = ??

Twisting the cable = ??
Untwisting the cable = ??

How do you know when to do which?
How do you know when to do both?

Sorry for the greenhorn question, I've learned a lot since I started but that's one thing that's still stumping me.

The brace and A2A specs are appox. only, they are not exact and can be adjusted somewhat.

I would start by taking about 6-8 twists out of the string and put about 2-3 twists in the cable, and see what that gives for a draw length change and go from there.

daveinohio
04-18-2011, 03:53 PM
I have a 2010 Pantera and I can take the string off after backing the limb bolts out until their ends are half-way through the barrel nut. Am I doing something I shouldn't be?

Spiker
04-18-2011, 08:53 PM
I have a 2010 Pantera and I can take the string off after backing the limb bolts out until their ends are half-way through the barrel nut. Am I doing something I shouldn't be?

No - other than taking your string off when you could be out shooting arrows. ;)

hunt123
04-19-2011, 06:04 AM
I have a 2010 Pantera and I can take the string off after backing the limb bolts out until their ends are half-way through the barrel nut. Am I doing something I shouldn't be?

After talking to Joel, that's what I tried too. The string wouldn't begin to come off. Maybe I have a "special" bow somehow, don't know.

HawgEnvy
04-19-2011, 06:33 AM
After talking to Joel, that's what I tried too. The string wouldn't begin to come off. Maybe I have a "special" bow somehow, don't know.

try gently pulling the string away from the idler while turning the idler towards the bottow cam.

bfisher
04-19-2011, 06:54 AM
Do you have a good hardware store or Fastenal anywhere nearby? You could try getting a pair of longer limb bolts. Maybe 1/4" or 1/2" longer would be enough to back them out farther for disassembly.

Wish you could post some pics of the cam at full draw; especially the module side. I'm having a hard time visualizing why the back wall would be spongy unless you're drawing the bow past the end of the module, which would indicate that the draw stop is set too long for the mod.

I know specs and such are just approximate, but the Pantera shows to max out at a 31" draw and that would be with the f7 module. Just a guess at this point but I'll bet if you have the draw stop set for 31.25" and put on the f7 module you're going to see a much better wall than what you now have. Just the fact that you can set the draw stop at 30" with the f6 mod leades me to believe you need to put on the f7 mod and maybe readjust the stop for it.

I know when I had my 2009 Moab and the draw stop was set too long for the module it had a spongy wall. I like to use the term "an ugly wall".

Now here's another question I haven't seen mentioned. Just what draw length do you intend to set the bow for? Between the sponginess and limb bolt problem I'm almost incllined to think there are several things out of whack with the bow, which should all be adjustable. I just think that maybe getting at least the a2a and brace height correct would give us a good starting point. Then work on cam orientation and proper mod/draw stop position.

hunt123
04-19-2011, 07:55 AM
try gently pulling the string away from the idler while turning the idler towards the bottow cam.
The string felt "guitar string tight" so I don't think I could have done that. Too tight to put a peep in.


Do you have a good hardware store or Fastenal anywhere nearby? You could try getting a pair of longer limb bolts. Maybe 1/4" or 1/2" longer would be enough to back them out farther for disassembly.

Wish you could post some pics of the cam at full draw; especially the module side. I'm having a hard time visualizing why the back wall would be spongy unless you're drawing the bow past the end of the module, which would indicate that the draw stop is set too long for the mod.

I know specs and such are just approximate, but the Pantera shows to max out at a 31" draw and that would be with the f7 module. Just a guess at this point but I'll bet if you have the draw stop set for 31.25" and put on the f7 module you're going to see a much better wall than what you now have. Just the fact that you can set the draw stop at 30" with the f6 mod leades me to believe you need to put on the f7 mod and maybe readjust the stop for it.

I know when I had my 2009 Moab and the draw stop was set too long for the module it had a spongy wall. I like to use the term "an ugly wall".

Now here's another question I haven't seen mentioned. Just what draw length do you intend to set the bow for? Between the sponginess and limb bolt problem I'm almost incllined to think there are several things out of whack with the bow, which should all be adjustable. I just think that maybe getting at least the a2a and brace height correct would give us a good starting point. Then work on cam orientation and proper mod/draw stop position.

You can replace those bolts? I thought they were some special bow thing. Does the bolt come out of the round plastic cap? Any idea of the thread pitch and the bolt dia? If I can get longer ones, I'll have to take them and the bow to a local shop that has a press so they can let it clear down and put the new bolts in. Very puzzling though, that some Pantera's can be disassembled and mine can't. Joel kind of let on that it might be a problem anyhow.

ATA and brace are factory spec (or close) right now.

In terms of draw length, if I'm shooting my thumb release I'd probably set it for 30.5". If I switch to a back tension, I have to increase it by 1/2" to 31" to compensate for the shorter head. That keeps my anchor at the same point.

There's a #7 module? Mine only go up to #6. That could be the problem. Good sleuthing. Thank you.

Oh...just this second realized I might have had a #7 on my Bengal and when I sent the bow back for replacement, they didn't send the module back. That would be why the Bengal's DL and wall felt better. I'll call them and see if they'll send me one. They sent the Pantera to me with a #5 and that's it. I just happened to have the others.

Sounds like that's going to solve the spongy back wall.

daveinohio
04-19-2011, 08:31 AM
I used the shaft of a philips screwdriver between the string and cam to lift the string out of the groove and reversed the process to put it back on.

hunt123
04-19-2011, 12:44 PM
I called Joel again and he's going to send me a full set of modules including #7 AND he's going to try to find a couple longer limb bolts. Thanks guys for the help!!!

Here's a few bow specs that seem strange to me, maybe they're OK for Panteras??
1) Tiller
Measuring from limb pocket to string - Top: 10", Bottom 10 1/4" Off by 1/4"
Measuring from a string stretched axle to axle to compensate for the larger bottom cam - Top: 8 3/8" Bottom: 8 3/4". Off by 3/8".
Before measuring, I tightened the limb bolts all the way down, then backed each one out the same number of turns to 60# which is where I'm shooting right now.

Tiller isn't close to being the same especially using the string on axle measurement. That one should be the closest.

2) Nock Height
Limbdriver rest is adjusted to center the arrow in the Berger holes. Nock is 7/16" above 90 degrees. Anything less than that produced vertical paper tears. At 7/16", it's shooting bullet holes. That's almost 1/2" above!!

Seems way too high to me, based on comments many others have made about their nock points.

Thoughts? Maybe these specs are OK? ATA and brace are factory spec. I measured them again.

Maybe the tiller being so screwed up causes the nock point to have to be that high? I tried making the tiller measurements be even but gave up because I couldn't figure out which way to turn which limb bolt to either reduce or increase the measurement.

So I cranked the bolts all the way down to start fresh.

It's shooting bullets on the paper rack so maybe I just forget about the weird specs and have fun??

bfisher
04-19-2011, 04:33 PM
Yes, those washers under the limb bolts are called bezels. They should be machined aluminum with a nylon or plastic washer between the limb and the bezel. Martin has them under part # BP-7 and come in 2", 2 1/4", or 2 1/2". You have to specify the length you want. Just measure the ones in your bow and go up from that.

I just did some disassembly of one of my bows to measure the bolts. They are
5/16"x18 (coarse thread). The ones on my Nemisis are 2" and 2 1/14" on my 2005ShadowCat. They are listed in Fastenal catalog as Flat Head Socket Cap Screws and length goes all the way to 4". Here's some part numbers.

.......Plain.................Holo Krome..............Zinc

2 1/4".......24261..........81261.................94261
2 1/2".......24262..........81262.................94262
2 3/4".......24263...................................942 63


Had to edit. Didn't see your last post, hunt. Still, this might be useful to somebody else.

hunt123
04-20-2011, 04:31 AM
Yes, those washers under the limb bolts are called bezels. They should be machined aluminum with a nylon or plastic washer between the limb and the bezel. Martin has them under part # BP-7 and come in 2", 2 1/4", or 2 1/2". You have to specify the length you want. Just measure the ones in your bow and go up from that.

I just did some disassembly of one of my bows to measure the bolts. They are
5/16"x18 (coarse thread). The ones on my Nemisis are 2" and 2 1/14" on my 2005ShadowCat. They are listed in Fastenal catalog as Flat Head Socket Cap Screws and length goes all the way to 4". Here's some part numbers.

.......Plain.................Holo Krome..............Zinc

2 1/4".......24261..........81261.................94261
2 1/2".......24262..........81262.................94262
2 3/4".......24263...................................942 63


Had to edit. Didn't see your last post, hunt. Still, this might be useful to somebody else.

Thank you! Very valuable info if Joel doesn't happen to send a couple longer ones. We have several Fastenal stores here and some real hardware stores. I measured my bolts and they're only 2". The pocket will allow at least 2 1/4" or maybe 2 1/2". Either of those should work.

BTW, did you just become Administrator recently? Seems like I remember you being a "senior member" not long ago. Congratulations!

MLN1963
04-20-2011, 06:11 AM
On my FC400 I can draw back and hit the draw stop and feel a pronounced stop. However, if you continue to add pressure you will get a mushy feeling because although the bottom cam is stopped the top cam will continue to rotate some. Some brands have draw stops on both cams and I can see it having some benefit.

I know you have an idler on top and not a cam but could it act the same way? Maybe this be what you are feeling on your Pantera?

hunt123
04-20-2011, 07:54 AM
On my FC400 I can draw back and hit the draw stop and feel a pronounced stop. However, if you continue to add pressure you will get a mushy feeling because although the bottom cam is stopped the top cam will continue to rotate some. Some brands have draw stops on both cams and I can see it having some benefit.

I know you have an idler on top and not a cam but could it act the same way? Maybe this be what you are feeling on your Pantera?

I'm pretty sure bfisher discovered the problem in a previous post. It's related to the DL module and where the stop needs to be set for each one. I'll know for sure when the #7 module arrives. Interesting that the Firecat doesn't have dual stops and you can "draw through" the wall.

bfisher
04-20-2011, 06:01 PM
I'm pretty sure bfisher discovered the problem in a previous post. It's related to the DL module and where the stop needs to be set for each one. I'll know for sure when the #7 module arrives. Interesting that the Firecat doesn't have dual stops and you can "draw through" the wall.

Not really. One stop works just fine. you gotta be one strong SOB to pull that top cam over once the bottom draw stop hits the limb. Besides, the stop is not necessary to stop the cam so much as an indicator of when the cam has hit full draw.

For what it's worth the Cat/Nitro cams must be shot with a draw stop. It's possible to overdraw the cam to a point where the cable rolls off the back end of the module in which case the bow will lock up in the full draw position (scary). This has only happened a few times with somebody who doesn't know about it, and I would also suspect someone who is drawing so much weight they can't control the draw cycle of the bow or one that is too short for them and they don't know about the issue.

I never shot the single cam without the draw stop but it might act the same way.

MLN1963
04-21-2011, 11:17 AM
You gotta be one strong SOB to pull that top cam over once the bottom draw stop hits the limb.


15 years ago I might have fell into that catagory, not anymore. It doesn't take that much pull and you can see the upper cable moving some after the lower has stopped.