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What to look for on derailed bow
I have worked on my bow (Mathews Drenalin), replaced string/cable, peep, etc using a Bowmaster press with no issues. I added some twists to my son'e bow a couple weeks ago using the fingers necessary with the Bowmaster and double checked everything but something happened on the first shot and we narrowly escaped some danger. The bow partially derailed and the arrow broke. No idea exactly what happened or why but I am scared to death to restring this thing and have it blow up on him.
What should I be looking for?
Bow specs, Bear Apprentice II, pulling 48#.
Did the broken arrow cause the derail? Could you have added too many twists to the cable and therefore caused cam lean that derailed it? I almost unpressed my bow once with the cable just outside the rail. It was on the inside of the rail in a hard to see spot. That’s a possibility too.
I would take it to a bow shop and explain what happened. Maybe they can figure it out.
Check the cams for micro cracks. Check the limbs for splinters.
Also, when a bow shop takes a bow out of the press they put it on the scale and slowly pull it down while watching the cams to make sure everything looks ok.
you can ue a cotton ball and rub it over the limbs to find any hairline cracks you may otherwise miss...
Should really check all the axels and bearings and everything for wrap page etcetera...
Life to short, buy him a new one ;)
My guess is a cable wasn't quite on one of the stops right and came off. With the energy in today's bows, when something slips it will get your attention.
If that were my sons bow I’d be off to a competent Pro Shop and either get it checked out there or trash it and get him a new bow from the pro shop. Good luck! C
I'd be looking for cracks in the limbs. No I wouldn't. I'd replace the limbs ;)
Some time back, I had to let down on a deer that heard me draw, and the tail of my jacket got between the string and cam, and the bow derailed. Ruined the cam, and I think cracked the limbs. I used that bow another three years before I sold it. The guy who bought it was smarter than me I guess, he had the limbs cotton balled at a shop. There was damage and I bought him some new limbs. I guess that's some sort of testament as to the quality of today's bows that the limbs never actually broke. Yeah, I'd have it gone over well at a good shop.
I'm a day late and a buck short on this, but I found this thread last night while looking for an answer to a similar problem so maybe someone else will see this and it will be helpful. In my opinion (and of course I wasn't there) the arrow was damaged on a previous shot. The damage wasn't noticed and it was shot again and broke instantly. This caused a near dry-fire effect and that is what derailed your string.
I had a cable break one time at full draw. The violent reaction of the bow coming apart broke the arrow somehow. Never did figure out how the arrow broke, but when something like that happens it gets your attention!
Take a cotton ball and go over the limbs. This is the best ways to find hairline cracks or splintered limbs. Also check the cams to make sure they didn't get bent.
Is be looking for a new bow
I saw this at least once a week in my shop. 99% of the time it was user error. Most of the de-rails come from letting down with your fingers. Almost always the bow gets torqued as you are letting down and the string and/or cable rolls off the side.
A competent pro shop will know within 10 minutes if something is beyond a simple re-stringing. If you don't have a "real" press, take it to a pro shop.
He's going to be scared to shoot it. Just for his confidence and to protect from target panic you should get him a new one. Or, he gets yours and you get new :)