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Saw catching flack

Started by CCC4, May 12, 2016, 02:07:54 PM

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CCC4

I am on a huge clearcut, everything except the steep ground is getting pushed over by either a Hydro Ax or dozers. I cut them all off the stumps and top and limb. Getting anywhere from 15 to 21 loads a week when rain is causing problems.

So here is the problem, my bar tips aren't last more than 2 weeks and my saw is being blamed. I run a 661 with a 20" bar. My boss and his brother say my saw is too much for the short bars. I on the other hand think it is from pinching the bar several times a day...which in this situation is almost unpreventable.

I use Stihl ES bars, Stihl E bars, and now using Forestry Pro Series bars. My boss is buying junk because I can't get any run time out of the ES bars. What seems to happens is between the tip roller and where it connects to the bar, I get a good dip formation. Then pretty quick the tips explodes. The other day on the Forestry Pro bar, the end tip sprocket blew directly in half after 1 week.

Thing that bothers me is I am supposed to be getting a JR 2188 in a few days and my boss is acting like it will be too stout for a short bar also. I could go to a 25" I guess and carry a Spencer tape. Right now with a 20" I can use the saw to mark my logs, it's more convient for me. Personally I don't think its the length...it's the pinching and abusive wear.

What do you guys think?

motohed

Sounds like , you need to turn the oiler up . I never grease a bar tip , I feel the chain oiler gives them better lubrication , than the grease . I think the grease collects dirt and prematurely wear out the bar tips .

sandsawmill14

i agree put all the oil you can to it :)  i dont see how length bar would matter on the size saw far as the tip wearing out ???
hudson 228, lucky knuckleboom,stihl 038 064 441 magnum

celliott

I would guess they think the big saw is spinning the chain faster, hence wearing the tip out faster?

A big saw like that doesn't rev higher than say a good 50cc saw, however, it will keep the RPM's higher in the cut with a short bar. But how often are saws run WOT with no load, where peak RPM's occur? Not often. The great majority is spent under load, where RPM's are lower. The difference between a 20" bar and a 25" bar on a 661, under load RPM's? I can't imagine it would be so different as to wear tips out faster...

I think you're right, pinching is hard on tips and bars.
Chris Elliott

Clark 666C cable skidder
Husqvarna and Jonsered pro saws
265rx clearing saw
Professional maple tubing installer and maple sugaring worker, part time logger

Al_Smith

Here of late there have been many reports of blowing the bar sprockets .I can't understand all that .In around 45 years I've only blown three and they were half worn out before I ever got them .

Is that chain as taut as a banjo string or something?FWIW to work properly a chain has to be able to slightly rock in and out of the cut .About enough slack looking at the bottom of the bar for the thickness of a nickle is about right .

sandsawmill14

we always run the chain snug to the bar you can pull up on the chain and it will give about 1/8" but there is no slack in the chain what so ever when you turn it loose :)
hudson 228, lucky knuckleboom,stihl 038 064 441 magnum

Cedar Eater

I was taught to leave the chain loose enough that when you pick it up in the center of the top of the bar, the nearest drive link almost clears the slot, especially if you are tightening when the saw is hot. I don't know why. That's about 5/16" - 3/8", depending on chain pitch.
Cedar Eater

Gearbox

I agree with cedar eater . Drive link clears bar when pulled up in center .
A bunch of chainsaws a BT6870 processer , TC 5 International track skidder and not near enough time

sandsawmill14

well on new bars i might can pick it 1/4 but as the bar wears you have run it tighter to keep it straight in the cut :)  but i wear bars out i will grind the edges 4 or 5 times before i give up  ;D
hudson 228, lucky knuckleboom,stihl 038 064 441 magnum

Texas-Jim

If your cutting the same size tree the bar length plays no role in the speed of the chain. Now a 36 inch will slow the tip speed if your cutting a 36 inch tree compared to a 24 inch but not by a drastic amount. Might try an oil with lithium added it tends stay put better and make sure oiler is turned up.
What we do in life echoes through eternity.

DelawhereJoe

How dirty of wood are you cutting, could you be picking up dirt, dust and other crud causing your bar tip to just be eaten out. Once the bearings fail its just toast, are you cutting mainly with the top of your bar or the bottom. Top bar cuts will put more pressure on that front sprocket  .
WD-40, DUCT TAPE, 024, 026, 362c-m, 041, homelite xl, JD 2510

Gearbox

I never have a problem with cutting straight if the chain is sharpened right . A bar shouldn't wear on one side .
A bunch of chainsaws a BT6870 processer , TC 5 International track skidder and not near enough time

sandsawmill14

the bar doesnt wear on one side (i dont think ??? never checked ) it just wears enough to let the chain lean left or right instead of standing up straight :) i will grind the bar edges when they need it and have to hammer the bar to tighten the groove up for chain i would guess after 10-12 chains (guessing cause i have never kept up with it) but i wear bars out  :D  you gotta be careful not to get the bar to tight or its scrap >:( done that a few times too ::) but most of my sawing is splitting logs in 1/2 I try not to lose but 2 4/4 (one off of each half) so i have to cut pretty straight and cant do that if everything is not right and then sometime i dont do so good and lose 3 or 4 inches :-[ i had to buy a new 25" a couple weeks ago because it got bent just a little and couldnt rip with it  but i can buck 24-30" logs with no problems. if i can remember it i will take some pics comparing the old bar and the new one to show the amount of wear the chain was off of the roller tip almost an 1/8 inch and still ran fine until it got bent :)
as far as ccc4 problem it has gotta be an oil prblem or pinching one i have neever had a roller go out on the stihl rollamatic bars.  ccc4 can you not replace the roller tips on the bar ???
hudson 228, lucky knuckleboom,stihl 038 064 441 magnum

HolmenTree

Quote from: CCC4 on May 12, 2016, 02:07:54 PM
So here is the problem, my bar tips aren't last more than 2 weeks and my saw is being blamed. I run a 661 with a 20" bar. My boss and his brother say my saw is too much for the short bars. I on the other hand think it is from pinching the bar several times a day...which in this situation is almost unpreventable.

What seems to happens is between the tip roller and where it connects to the bar, I get a good dip formation.

I've run 18"-20" on 90 cc saws for years and never had a problem.
Biggest problem like you said is trying to avoid pinching the bar nose when cutting.
The 90 cc saw has enough power to still rotate the chain when you get the sprocket nose pinched when limbing and topping for example. When the chain rotates for even a second when the nose halves are squeezed against the sprocket bearing there's enough heat damage applied to the little roller bearings in the sprocket for them to fail along with the race splitting to blow the sprocket apart later on during normal use. Just be careful when pinching the nose and gunning the throttle.

Dip wear formation at the sprocket nose joint is simply  due to loose chain tension  causing repetitive chain impacting on the rails at that area, especially problematic when doing lots of limbing.
A rolled over penned wire edge starts to develop on the bar rails but wear differently on the nose rails because of different hardness between the two, thats why a dip starts to develop at that joint.
If the rolled over wire edge is not regularly filed off with a flat file the rails will  start to deteriorate.
Making a living with a saw since age 16.

Plankton

I ussually run longer but I ran a 20" on my jred 2188 for a few weeks didn't do anything to the bar.

One thing I've noticed I blew a few tips doing is I cut into the tension on a limb if that's the way my saw is moving already I try to keep my limbing constant and smooth, big saw has enough power to cut through the pinch without slowing so that's what I do. I have gotten two tips in the last few months with those grooves in them and I think it's from that.

Doesn't sound like a good site to be cutting on, stay safe

weimedog

I don't understand the logic about a big saw being too much for a 20inch bar. All we have around here is hard wood. Most of the pro's use Husqvarna 390's and Stihl MS660's now 661's. Most also use 20 inch bars although since the lighter weigh Total's are around they are gaining popularity in 24inch..:)

I do have one logger who destroys tips...with 372's I know he's rough on everything.  Also know he's stronger than most......bulls. And likes to plunge cut the back cut and work out. I wonder if that approach with a stronger than average person is why the tips fail faster on his bars.

Also agree with the already mentioned bar oil opinions .. more the better for those stressed tips vs. grease that seems to attract grit and sand.

Over tightening a chain has to effect both tip life AND main bearing life on some saws.

On the folks that use both Stihl brand and Total brand bars along with other's that I deal with, it seems to me the operator has more effect on the tip life than the brand....:)
Husqvarna 365sp/372xpw Blend, Jonsered 2171 51.4mm XPW build,562xp HTSS, 560 HTSS, 272XP, 61/272XP, 555, 257, 242, 238, Homelite S-XL 925, XP-1020A, Super XL (Dad's saw); Jonsered 2094, Three 920's, CS-2172, Solo 603; 3 Huztl MS660's (2 54mm and 1 56mm)

Ada Shaker

Could be that your bars overheating, causing annealing as it cools down slowly which in turn makes the steel softer. Once the steel is soft it will wear down very quickly. You might notice the tips of the bar turning blue before they start to wear down and fail.  I don't know what sort of steel they use for bars but you'd look kind of silly walking around from tree to tree with a chainsaw in one hand and a bucked of brime/coolant in the other. :D
If it hangs to the left, your likely to be a Husqvarna man.
If it hangs to the right, your likely to be a Stihl man.
Anything else is an uncomfortable compromise.
                             AND
Walking with one foot on either side of a barbed wire fence can become extremely uncomfortable at times.

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