The Forestry Forum

General Forestry => Chainsaws => Topic started by: mike_belben on April 20, 2018, 09:23:23 PM

Title: Loose sprocket tip
Post by: mike_belben on April 20, 2018, 09:23:23 PM
I have a no name 24" large pattern husky bar with an oregon style 3/8 sprocket insert.  Recently it loosened up and started wobbling around quite a lot.  It was binding in the wood a bit and also getting a wear patch right where the rails of the tip and bar meet due to misalignment.   

I pounded on the rivet but that did nothing.  Brought the bar to local co-op saw shop (which i think highly of) and theyd never seen it happen.  Bought a new oem oregon tip and swapped it on.  Still the same.  Id never changed a tip before but didnt see any issues.  


Anyone got any ideas? 
Title: Re: Loose sprocket tip
Post by: starmac on April 20, 2018, 09:27:05 PM
Are you saying that the sprocket is loose in the new tip too?
I have never changed a tip either, but it seems weird that the new one would be loose too.
Title: Re: Loose sprocket tip
Post by: mike_belben on April 20, 2018, 09:39:45 PM
No no, sorry.   The sprockets are both fine. The insert is loose in the end of the bar.  Do these normally get loctited in or something?
Title: Re: Loose sprocket tip
Post by: sawguy21 on April 20, 2018, 09:48:36 PM
It sounds like the rivet holes in the bar are enlarged, the metal must be soft. How old is it?
Title: Re: Loose sprocket tip
Post by: Skeans1 on April 20, 2018, 10:24:02 PM
Iíve had them wear out like that before Mike, had to get a new bar in my case they had worn so bad the seats of the tip didnít hold it tight anymore.
Title: Re: Loose sprocket tip
Post by: mike_belben on April 20, 2018, 10:28:28 PM
I checked the hole and it held the rivet tight, i was wondering if these are supposed to have a hole offset to pull the tip in maybe.  


If its destined to wobble ill probably braze the old one back on and save this new tip for the next one.
Title: Re: Loose sprocket tip
Post by: ehp on April 21, 2018, 04:25:23 PM
that happens a lot and I mean a lot if your cutting in the bush for a living . How did I fix that problem, I went to a different bar maker . The older 5 rivot Windsor speed tip bar was a lot worse than the Oregon bar for coming loose
Title: Re: Loose sprocket tip
Post by: DelawhereJoe on April 21, 2018, 05:30:54 PM
I've got a country line (TSC) bar has less 5 cords on it and the replaceable tip is just starting to come loose/wiggle. All I was going to do was drill down into the bar in 4 spots (2 on each side) and tack weld it then grind/sand it smooth.
Title: Re: Loose sprocket tip
Post by: Maine logger88 on April 22, 2018, 11:01:49 AM
Iíve had Oregon bars do that but usually after several replacement tips. Probably just have to weld it or braze it and throw it when the tip blows. Iím trying a sugihara bar hoping it will last better than Iíve experienced with Oregon...
Title: Re: Loose sprocket tip
Post by: Skeans1 on April 22, 2018, 11:17:12 AM
Sugihara is a great bar hard rails the tips are ok about the same as Oregon for life.
Title: Re: Loose sprocket tip
Post by: ehp on April 23, 2018, 12:58:53 PM
those bars are better than Oregon, I run them on my huskies. I find I have to take it easy on the first part of the tank or I get tip problems right off the start, after a tank they seem good to go . Have found thou the chain can pull down into the tip on them but the last bunch of bars I have not had that problem
Title: Re: Loose sprocket tip
Post by: Grandedog on April 24, 2018, 04:04:29 PM
     Howdy,

   Ed mentioned the Windsor bars back in the day were more stable than the Oregon because of the long recess tang. Back when Weyerhauser was cutting St. Helens, Windsor sold tons of bars and probably even more tips to them. Guys were going through a tip or better a day. They didn't bother even riveting the tip in. Just roll the chain off and slide in a new tip and back to cutting Douglas Cement.

Regards
Gregg
Title: Re: Loose sprocket tip
Post by: Skeans1 on April 24, 2018, 09:24:30 PM
Iíve heard those stories Gregg and guys buying new saws once a month itís impressive to still see to this day.
Title: Re: Loose sprocket tip
Post by: joe_indi on April 24, 2018, 11:09:16 PM
Sometimes the hole on the bar might have worn and become bigger. In such cases before flattening out the rivet, using a center punch with a heavier hammer causes the rivet to become fatter and tighten up in the hole. Tap it flat only after this. This should help
Title: Re: Loose sprocket tip
Post by: mike_belben on April 25, 2018, 10:10:22 AM
I measured them all, no wear in any dimension, rivets were tight fit. 

Im guessing its a chinese clone and some ching chong loctite knockoff is what kept the first tip in there snug enough for initial sale.   Heat would cook that out over time.  


Unfortunately, there is no evidence this bar was ever manufactured for a good fit.
Title: Re: Loose sprocket tip
Post by: DelawhereJoe on April 25, 2018, 10:18:28 AM
How are the bar rails holding up? If the rails are holding up good and you just tack weld on a new tip you could just drill out the tack weld then tack on a new tip.
Title: Re: Loose sprocket tip
Post by: mike_belben on April 25, 2018, 03:38:54 PM
Kinda wore a bit fast IMO but i redressed it entirely when i did the tip. 
Title: Re: Loose sprocket tip
Post by: ehp on April 25, 2018, 11:38:14 PM
in the 80's and 90's   I use to buy tips in a 10 pack and that may not last the week in the winter time for just me