Usually equipment fails due to user error, I’ve already sheared off two 880 tensioners from the side cover bolts not being tightened enough, one of which has happened today! I’ve then just used a borowed 880 with my mill, securely!, then one board and less than 6 inches into the the log again and I’ve broken the nose sprocket in my 4ft milling bar! which is a first for me! Took me a minute to realise the issue as the chain had seized, not derailed and the tensioner was stuck. Photos of the horse chestnut log I was milling and how the nose sprocket looked after the damage. Has anyone had issues with bar sprockets before? chain was too tight during the first cut I thought, so I detensioned it less than a full turn and some how it’s pulled the sprocket out! Any ideas on why this might of happened? so I can avoid it in the future..
Not what I needed at the start of a job and with a milling job tomorrow!
Update, I got my bar’s nose sprocket replaced couple of weeks ago and will post my latest milling job on here soon! ———— Yes, I admit I could of probably prevented this, by having proper tension and lubrication of the chain.
Which make bar was it which you broke? Sounds dangerous with the sprocket firing off, do you not have the safety catch on the nose end of the mill or did it not prevent the projectile? I’ve heard Sugi bars are good, but what are they like for milling? And do the chains fire off when they snap? I’ve never come across that before fortunately, just the occasional derailing of them.
Thank you for sharing your experiences, it is informative!
Not sure if writing this is an admission of improper use or not.
I mill as a hobby. 90% of the wood is from domestic property.
In my early setup I used a 660 on an Alaskan copy. 36" bar 3/8 full chiz No issues except some of the timber was too big for the max 28-9"cut.
First upgrade Panthermill (chainsawbars.com) running 42" 3/8 Lo-Pro + ripping chain.
This setup I snapped 3 chains and destroyed 2 nose sprockets. Almost copies of your pic.
Snapped chains were mainly down to foreign objects n the wood and the sudden stop of the chain while on full throttle.
Nose sprockets? No Idea. I used the grease point regularly, but put failure down to the fact the bearings/faces weren't wide enough to cope. They both went off like firecrackers. On sprocket piece lodged in nearby fence panel.
Last(?) - latest upgrade is running normal stihl 36" 3/8 ripper on the Alaskan - no issues
and running a 46" Sugi Pro bar on the Panther using 881 and a .404 skip chain - ripping. Again, no issues.
Hope this helps.