Hello, After a few nice training sessions, I had an unpleasant experience. My bow derailed (upper cam). Unfortunately I have to send the bow in. Now I want to try (as far as I can) to understand what might have happened. The bow placed 5 arrows too low on the target during the last training session (slow arrows?). I was surprised and adjusted the sight. The next arrow hit the center. Then something strange happened. Either I didn't put an arrow in the bow or I shot another arrow which also hit pretty much in the middle. Then the string came off the upper cam and hung down the bow. I was a bit perplexed, so I doubt my memory. But I am very sure that I shot an arrow (there were 2 in the target). During the first group of 5 I had the feeling of torque, so I changed my grip to rule out torque. I fired the bow with a UV thumb release. After reading several articles and some chatgpt I came across the topic of cam synchronization. What do you think? What could have gone wrong? Why was the first group of 5 too low? Is this related to the incident? I will make a few pictures of the upper cam in order to show the marks the bowstring may have caused while derailing. Pretty upset and feeling stupid ... PS: When the string came of it was pretty slow and dongling around, no sharp bow explosion sound either. More like a non agrresive slipping from the cam. I dont understand what happened. Limbs look fine.
In my experience, I have only seen a string derail from a dry fire (no arrow in the bow) or an immense amount of torque being applied at full draw. The string track on the Switchweight cam that is on the Phase 4 is extra deep to help prevent this exact thing from happening, so I can't imagine how much torque it would take to actually derail a string during the shot, but it would be quite a bit. Cam synchronization is about the cams turning over at the exact same time during the draw cycle and typically affects nock travel vertically, not side-to-side. I can't say I've ever heard of a bow being out of time that caused a derailing issue. As for your arrows hitting low, that's not necessarily a mechanical issue. It's entirely possible that you are anchoring differently, gripping the bow differently, or dropping your arm when you shoot. All of which will affect your point of impact. I would take the bow to a local dealer and have them pull it apart and make sure the cam and axle aren't bent, and there are no issues with your limbs or string damage. If the bow wasn't dry fired they should be able to put it all back together and get back to shooting.
Although I completely agree with Justin I'll add I have seen this on bows set very low on their DW. My nephew had a mission set at 38lbs and it would come off all the time. Once we set it to 50 the problem went away What's yours set at. Sent from my Pixel 6 using Tapatalk
Thanks a lot for your answers. I just cannot imagine myself attaching the thumb release, drawing the bow and looking through the peep sight without an arrow in the bow. But who knows .... The bow is a 60lb DW, 30inch DL, 29inch AA Dont get me wrong. I have no problem in admitting that I am a fool without experience messing up fine equipment although I try to be very careful. I just feel uncomfortable shooting again without understanding what happened. The upper cam (from where the string came off) seems perfectly fine apart from the scuff marks (series of 3, assume from string coming off) and a strange dent. The dent (red circle leaves a small burr in the stringtrack). I assume that this dent was there before the derailing. What would have happened when dryfireing this bow at 60 lbs and 30 inch draw length (this configuration is the previous owners, I already ordered 28.5 inch mods for myself). As I mentioned already the string snapping was not agressive, dry firing a compound bow in videos sounds aggressive usually.
Thanks a lot for your answers. I just cannot imagine myself attaching the thumb release, drawing the bow and looking through the peep sight without an arrow in the bow. But who knows .... The bow is a 60lb DW, 30inch DL, 29inch AA Dont get me wrong. I have no problem in admitting that I am a fool without experience messing up fine equipment although I try to be very careful. I just feel uncomfortable shooting again without understanding what happened. The upper cam (from where the string came off) seems perfectly fine apart from the scuff marks (series of 3, assume from string coming off) and a strange dent. The dent (red circle leaves a small burr in the stringtrack). I assume that this dent was there before the derailing. What would have happened when dryfireing this bow at 60 lbs and 30 inch draw length (this configuration is the previous owners, I already ordered 28.5 inch mods for myself). As I mentioned already the string snapping was not agressive, dry firing a compound bow in videos sounds aggressive usually.
That looks like normal wear & tear on your cam - especially if you're hunting with that bow. Your string isn't hard enough to dig into the metal of the cam, even if the bow derails. The only thing to potentially worry about is abnormal wear on your serving from that burr if it's on the inside of the string track. A quick rub with some sandpaper to file it down will take care of it. And yes, dry firing your bow sounds a lot like a .22 going off in your hand. If you don't recall that happening, it's entirely possible the bow derailed on the shot for some unknown reason. Again, I would have a local pro shop look it all over, put it back together, then draw it back a few times to see how things look. It's possible the bow is way out of tune and you have an excessive amount of cam lean at full draw, which could be factoring into why it derailed.
Thanks a lot. I will send the bow to a bow shop here in Spain. Will come back and tell you what they told me.
