Freakingstang
Doctor Freakinstein
not today, just observing.
"loading" the saw and running in 346xp/5100s
- Thread starter wildbio
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not today, just observing.
manual
Addicted to ArboristSite
Dang you could have said the the rings do make a seal on there own.
Ok , Thanks Steve. LOL
They do but not enough
HUSKYMAN
Addicted to ArboristSite
They make enough for the saw to start. The oil in the engine is also a factor in ring sealing.
Crofter
Addicted to ArboristSite
Sounds like good old fashioned quibbling! Manual there are a few other things you should add to your list of prerequisites for combustion.Lol!
On four strokes especially the oil control rings spring tension is much more of an activating factor since they are somewhat sheltered from compression and combustion pressure differential and they work in a smooth bore. On a two stroke, at least saws, the cylinder is interrupted with the intake, exhaust and transfer ports and excessive ring expansion pressure would be a liability. Both compression and combustion pressures expand the ring to effect the sealing force; Combustion being some 5 or more times higher. There are a lot of different cylinder liner surfaces from cast iron to steel to chrome and now nikasil. Different ring materials are required for the best compatabiliy with the cylinder surfaces and I am sure that initial wear in is part of the equation. I have not heard any stories of glazing and failing to seat being a problem or needing any special considerations for break in. Normal chain saw operation usually gives enough variety that it is not a concern.
On four strokes especially the oil control rings spring tension is much more of an activating factor since they are somewhat sheltered from compression and combustion pressure differential and they work in a smooth bore. On a two stroke, at least saws, the cylinder is interrupted with the intake, exhaust and transfer ports and excessive ring expansion pressure would be a liability. Both compression and combustion pressures expand the ring to effect the sealing force; Combustion being some 5 or more times higher. There are a lot of different cylinder liner surfaces from cast iron to steel to chrome and now nikasil. Different ring materials are required for the best compatabiliy with the cylinder surfaces and I am sure that initial wear in is part of the equation. I have not heard any stories of glazing and failing to seat being a problem or needing any special considerations for break in. Normal chain saw operation usually gives enough variety that it is not a concern.
wildbio
ArboristSite Operative
now we're getting somewhere
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manual
Addicted to ArboristSite
Yeah frank My bad.
I figured that out after you posted. thanks
So Lets just stick with 2 cycles and rings of a conventional manner.
Now what you are saying. you are right.
I am not trying to quibble, Just trying to let people understand that it makes no differance using a .325 chain or a .375 chain to break in a saw.
wildbio
ArboristSite Operative
are you guys going to get the
'loading" of the saw and what if any influence it has on all this?
please
'loading" of the saw and what if any influence it has on all this?
please
manual
Addicted to ArboristSite
Ok
Normally gas pressure in the upper cylinder holds the ring down against the bottom of its groove and out against the cylinder, forming a seal
Normally gas pressure in the upper cylinder holds the ring down against the bottom of its groove and out against the cylinder, forming a seal
wildbio
ArboristSite Operative
i'm listening and learning
manual
Addicted to ArboristSite
Now there is such a thing called ring flutter
Freakingstang
Doctor Freakinstein
go manny go. you're on a roll now
manual
Addicted to ArboristSite
Step in steve,
This could be a thread that we can converse on and not try to out wit one an other.
I'm game.
Franks post are great too.
This could be a thread that we can converse on and not try to out wit one an other.
I'm game.
Franks post are great too.
ciscoguy01
Addicted to ArboristSite
eh?Crofter
Addicted to ArboristSite
Can be more of a problem on multiple ring setups where a lower ring, because it is in the "pressure shade" of the upper ring does not seal as firmly and it flutters; then there is the other scenario where the upper ring gets worn and pressure builds between it and the second ring and there is then no pressure differential to keep the upper pressed out and to the bottom of its ring land, and it flutters
One thin ring more better for extreme rpm but about as important to the usual operation of a firewood saw as a recipe for fish stew; probably a little better than "what is the best brand of bar oil" though, Lol!
SawTroll
Information Collector
Looks like another myth is killed, thanks to Frank!!!
...but it will surely turn up again......opcorn: opcorn:
...but it will surely turn up again......
opcorn: opcorn:
SawTroll
Information Collector
I am a bit puzzled at this as well - but I have read enough about it to put an 8-pin .325 on the NE346xp a bit sooner than I originally thought - it probably will put an even heavier load to it than a 3/8 7-pin will, with 21LP chain.....
Back to the original plan (.325x7 for run-in) - I think.....
Edit:
...but sertainly not 95VP - it simply doesn't do the saw justise, and is quite a bit slower than the 21LP on that saw.
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wildbio
ArboristSite Operative
Back to the original plan (.325x7 for run-in) - I think.....
Me to. I still have the 20nk on my 18"bar with 7pin .325 sprocket. The little bit of cutting that I've done with it I liked it a lot (better than the 95VP for certain). It is a more aggressive chain and really bit into the wood. I did feel it was "loading" the saw just fine. I have yet to try the 20LP that i have for it. I feel better about not having switched to 3/8 now. Hey I might still but it would be for the convenience of keeping everything 3/8"
Something I've been thinking about: if loading the 2-stroke were that important to running-in the saw then just about every 2-stroke string trimmer out there would not get broken in properly.
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Its a sweet little saw and its got power I am happy!!!
Well as we all expected running in a 346NE with the factory chain and bar (a 16" with 95vp .325 anyway) is just what you would expect, it was set up by Husky to run perfectly and break in properly out of the box and it did just that. It could be loaded properly with no problem it wasn't under chained at all and the oiler was set just right also.
Naturally I never freewheeled it at rpm or idled it long but just nice easy full throttle cuts in dry soft cottonwood limbs about 10-12" dia and just a little idle between cuts and ran two tanks of fuel thru it this outing, and of course it got quicker and snapier as I ran it so I am thinking later on it will really perform!
I cant see me making any big huge changes with chain pitch etc and all that I dont make my own chains so its not a big deal to me to have all my saws using the same chain. I will just leave this saw alone except probly get rid of the cat later. I have a non-epa on the way but will probably wait till the saw is good and broke in before changing it out?
Well as we all expected running in a 346NE with the factory chain and bar (a 16" with 95vp .325 anyway) is just what you would expect, it was set up by Husky to run perfectly and break in properly out of the box and it did just that. It could be loaded properly with no problem it wasn't under chained at all and the oiler was set just right also.
Naturally I never freewheeled it at rpm or idled it long but just nice easy full throttle cuts in dry soft cottonwood limbs about 10-12" dia and just a little idle between cuts and ran two tanks of fuel thru it this outing, and of course it got quicker and snapier as I ran it so I am thinking later on it will really perform!
I cant see me making any big huge changes with chain pitch etc and all that I dont make my own chains so its not a big deal to me to have all my saws using the same chain. I will just leave this saw alone except probly get rid of the cat later. I have a non-epa on the way but will probably wait till the saw is good and broke in before changing it out?
outdoortype
ArboristSite Guru
Where do you get a .325 X 8 tooth sprocket?
I've been toying with the idea for another Husky but their IPL doesn't list a .325x8 nor does Oregon. Also, it appears that switch from 3/8 to .325 requires switching the "worm wheel" which engages the pump I believe. I'm wondering if this wouldn't have to be larger in order to mesh with the sprocket rim?
I am a bit puzzled at this as well - but I have read enough about it to put an 8-pin .325 on the NE346xp a bit sooner than I originally thought - it probably will put an even heavier load to it than a 3/8 7-pin will, with 21LP chain.....
I've been toying with the idea for another Husky but their IPL doesn't list a .325x8 nor does Oregon. Also, it appears that switch from 3/8 to .325 requires switching the "worm wheel" which engages the pump I believe. I'm wondering if this wouldn't have to be larger in order to mesh with the sprocket rim?
huskydave
Addicted to ArboristSite
I tried out a 9pin .325 Stihl sprocket today on my modded ms260. I have determined this combo is very close to a 3/8 8pin setup and the 3/8 chain is a hair quicker. The 9pin gets the chain moving so quick that chip removal becomes a problem in 8"+ wood but both setups are good. Im going to use the .325 chain for a while but switch back to the 3/8 chain because it seems to be the best setup. I am running a 16"stihl rollamatic bar.
