Sounds (and looks) to me like a casting flaw that finally let go. Note the somewhat coarse grain structure of the housing where the stud broke off. Not good, when it comes to aluminum casting.
My friend had this exact thing happen to his Daiwa BackBay LT3000, which was an otherwise pretty stout and VERY smooth reel. Apparently these cast-in oscillation gear studs are a higher-stress point than I previously considered.
After doing some on-line research and speaking with the repair rep from The Tackle Trap (well-known Daiwa-centric shop) I learned this is a weak-ish point in Daiwa's now-discontinued LT (Light Tough) line of reels. Oh great, and I own two, a Ballistic LT (carbon bodied) and a Procyon LT (aluminum). Neither has shown any sign of this problem, but I'm now aware that it could be a ticking time bomb. Or maybe not, it's a very isolated, but real issue.
Now I see that its not just Daiwa, but Penn as well. Oh goodie, I have a Penn Clash II as well. Looks identical to the subject Slammer inside. But again, no issues in two years of intermittent use doing the tog jig thing. In retrospect, I do believe it's all about casting flaws, as well as a bit of under designing of the frame itself. Maybe this issue happens, maybe it doesn't. But if you have used a reel for years without seeing this problem then I would think you're probably good to go with that particular reel. But, there's such a thing as cumulative metal fatigue as well. So who can say what really causes such catastrophic failures?
Every manufacturer has some issue or other with their products. Notably, Shimano with their ridiculously fine-toothed "MicroModule" and MicroModule II" gears that do not seem to hold up for more than a few seasons of heavy use. Abu with their previously funky bait casting reel sticky free spool thumbars and fragile aluminum main reels (Gen 3 Revos notably so). Daiwa with their absurd magnetic oil sealing - said oil not available from Daiwa for DIY maintenance of course! MQ reels requiring special side plate opening tools, which are tough to source as well. Not to mention the over-engineering of those MQ reels (see my recent post on that subject, if interested). Oh and Daiwa's use of zinc (zinc!) main gears in their BG MQ and Saltist MQ reels. Zinc gearing in multi-hundred dollar reels is always a solid idea.
No reel is perfect, that's for sure. It's just that some are "less imperfect" than others. The "reel" job is to find those and then stick with them. That's kinda the idea of this board, right?
