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chunky

chunky

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I just gave in and bought me a MS070 clone to do just a little milling around the house. Ive read in other threads about running rich and different types of "good" bar oil but cant seem to find those of late. I`m 5 pages into this thread and haven`t run across any on those subjects. Ive mixed up some 40:1 to run a few tanks through the saw, while I`m waiting on my ripping chains to get here before i start any milling.
Can someone shine a light on a good milling mixture and a good bar oil before i get started as well?
 

J D

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Rich & oily isn't a bad idea for a new saw. Ideally put a few hours on it before you bolt the mill to it too.
I mill with 32:1 (quality synthetic) mix & tuned a bit rich (300-500 RPM below max WOT).
The best bar oil is lots of bar oil... A sticky bar oil will help it hang around & get where it needs to. If your milling more than 36" you might want to consider an aux oiler.
 
chunky

chunky

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Rich & oily isn't a bad idea for a new saw. Ideally put a few hours on it before you bolt the mill to it too.
I mill with 32:1 (quality synthetic) mix & tuned a bit rich (300-500 RPM below max WOT).
The best bar oil is lots of bar oil... A sticky bar oil will help it hang around & get where it needs to. If your milling more than 36" you might want to consider an aux oiler.

I`m on the second tanks of gas and was planning on trying to use a 3rd before doing any milling. I`ve got a 36" bar on it but for the milling it`ll be a 30" bar with only a 24" mill. Yesterday I noticed the auto oiler wasn`t working and i had to manually pump oil so I will have a aux oiler attached so I don`t have to remember to manually oil as I`m milling.
You mentioned "tuned rich"...this saw idles high enough for the chain to run pretty fast without exceleration. Is that normal for these big saws?
 

J D

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Yesterday I noticed the auto oiler wasn`t working and i had to manually pump oil so I will have a aux oiler attached so I don`t have to remember to manually oil as I`m milling.
I'd suggest sorting the saws oiler out before you worry about an aux oiler... That's one of the things a lot of people choose to replace with the OEM part
this saw idles high enough for the chain to run pretty fast without exceleration. Is that normal for these big saws?
That's not normal for any saw & not safe... you need to properly tune the saw! Asides from the high idle, if it's running lean you'll burn it up in short order
 
SeMoTony

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I`m on the second tanks of gas and was planning on trying to use a 3rd before doing any milling. I`ve got a 36" bar on it but for the milling it`ll be a 30" bar with only a 24" mill. Yesterday I noticed the auto oiler wasn`t working and i had to manually pump oil so I will have a aux oiler attached so I don`t have to remember to manually oil as I`m milling.
You mentioned "tuned rich"...this saw idles high enough for the chain to run pretty fast without exceleration. Is that normal for these big saws?

As ^^^^^ tune the idle then tune for high end. Lean is an amount of gas in the mix. Thus 32:1 is a leaner mix than 40:1 or50:1 and requires more mix to stay away from a hot/lean mix. Admittedly it's marginal but, when milling, it has more importance than cross cutting. Continously running for several minutes per slab adds up way quicker than cutting across and moving to next cut while PH idles and cools a bit
G'day gents
 

J D

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Lean is an amount of gas in the mix. Thus 32:1 is a leaner mix than 40:1 or50:1 and requires more mix to stay away from a hot/lean mix.
While you are correct, I think referring to a heavier oil mix as a leaner petrol mix just confuses things for some people.
What's important is to run an appropriate fuel : oil mix & tune the saw for the particular oil & mix ratio you are using (yes, oil variant can make a difference too).
I also think we are getting off topic & @chunky should probably start a new thread for further discussion
 
SeMoTony

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While you are correct, I think referring to a heavier oil mix as a leaner petrol mix just confuses things for some people.
What's important is to run an appropriate fuel : oil mix & tune the saw for the particular oil & mix ratio you are using (yes, oil variant can make a difference too).
I also think we are getting off topic & @chunky should probably start a new thread for further discussion
Facts are not confusing to people who are paying attention. A correct tune of carb @32:1 will be lean enough if switched to 50:1 at same carb setting to overheat rings when milling. Experience, sounds like PH really pulling for a while )<: then compression starts going away.
Rich or lean refer to quantity fuel that burns for power. Over or below ideal amount for complete burn for power.. PERIOD
 

J D

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Facts are not confusing to people who are paying attention. A correct tune of carb @32:1 will be lean enough if switched to 50:1 at same carb setting to overheat rings when milling. Experience, sounds like PH really pulling for a while )<: then compression starts going away.
Rich or lean refer to quantity fuel that burns for power. Over or below ideal amount for complete burn for power.. PERIOD
I'm fairly confident I'm paying attention, & also that you just proved my point....
A correctly tuned carb @32:1 will be RICH if switched to 50:1 at same carb setting.
To put it another way, increasing the ratio of oil in a fuel oil mix reduces the proportion of fuel in that mix. If the carb is not adjusted to compensate then it will meter out the same amount of mix but there will be less fuel in that mix, causing the engine to run lean.
Oil richness & fuel richness are different but related things. Changing oil richness by altering your mix will inversely affect fuel richness, fuel richness is corrected by carb adjustment.
There are plenty of discussions covering this both here on AS & elsewhere.
 
SeMoTony

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I'm fairly confident I'm paying attention, & also that you just proved my point....
A correctly tuned carb @32:1 will be RICH if switched to 50:1 at same carb setting.
To put it another way, increasing the ratio of oil in a fuel oil mix reduces the proportion of fuel in that mix. If the carb is not adjusted to compensate then it will meter out the same amount of mix but there will be less fuel in that mix, causing the engine to run lean.
Oil richness & fuel richness are different but related things. Changing oil richness by altering your mix will inversely affect fuel richness, fuel richness is corrected by carb adjustment.
There are plenty of discussions covering this both here on AS & elsewhere.
Yes I stated it backwards, thanks for that correction. "Oil richness " is not correct position. Rich or lean refers ONLY to fuel, lean leaves unused oxygen to eat away ,by burning ,metal in combustion chamber. Rich has excess fuel that cuts back on power. There is an ideal weight ratio of air to fuel.. lean means that ratio is less weight of fuel,, rich means there is more fuel than the ideal.. Glad to hear your confusion of what Rich and lean means. Makes it easier to say " it ain't that way"
This understanding for me goes back into 60's with carcraft and other performance car mags. It is also why a ported head has rough surface on intake an polished on exhaust. Polished intake chills and fuel will condense on wall and lead to varying levels of fuel to air ratio as it condenses to then have a portion go back into air flo richening and leaning. Rough intake surface is turbulent keeping the fluid in mix with the air.
 
chunky

chunky

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While you are correct, I think referring to a heavier oil mix as a leaner petrol mix just confuses things for some people.
What's important is to run an appropriate fuel : oil mix & tune the saw for the particular oil & mix ratio you are using (yes, oil variant can make a difference too).
I also think we are getting off topic & @chunky should probably start a new thread for further discussion

Reading this thread and a lot of other threads, I`ve seen a lot of NEWBIES like myself that has little/no knowledge of this tuning discussion. The title of this thread is why I came here instead of starting a new one but it`s no problem to move the discussion if needed.
 
SeMoTony

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Reading this thread and a lot of other threads, I`ve seen a lot of NEWBIES like myself that has little/no knowledge of this tuning discussion. The title of this thread is why I came here instead of starting a new one but it`s no problem to move the discussion if needed.
On pre EPA saws there is a beginning point. On the Stihl saws I have it was idle one turn out on idle fuel same On throttle/butterfly open. Once the idle is correct then the Wide Open Throttle is addressed when saw is warmed up.
When the chain moves at idle the butterfly may be too open, backing the screw out for that out will bring things closer to order.
The idle mix screw can be either side of just right. Turning that screw in will lean the air fuel mix, counter clockwise will richen the fuel (usually good) to bring it all in. The saw idling slow enough to not engage the clutch, but be able to come up to speed as the throttle is opened. If the, warmed up engine, isn't fairly smooth in coming up to speed the high end screw will need adjustment. Particularly when it ends up running hard and fast until a cut is started and the engine falls on its face. Indicates too little fuel, lean. Open up the high end fuel screw CCW on my Stihl saws til there is power to cut. Open up about 1/8th turn atta time til the cutting slows down a bit. At that point the air/fuel mix is just rich, which has the PH a bit cooler. Opening up the muffler (a search topic will get you there) cools the PH by letting the heat out faster.
For actual videos of the sounds of correctly tuned saws placing "tuning a saw" in the search will make available more than enough info to start you and your saw in good stead.
Mill safely
 
chunky

chunky

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On pre EPA saws there is a beginning point. On the Stihl saws I have it was idle one turn out on idle fuel same On throttle/butterfly open. Once the idle is correct then the Wide Open Throttle is addressed when saw is warmed up.
When the chain moves at idle the butterfly may be too open, backing the screw out for that out will bring things closer to order.
The idle mix screw can be either side of just right. Turning that screw in will lean the air fuel mix, counter clockwise will richen the fuel (usually good) to bring it all in. The saw idling slow enough to not engage the clutch, but be able to come up to speed as the throttle is opened. If the, warmed up engine, isn't fairly smooth in coming up to speed the high end screw will need adjustment. Particularly when it ends up running hard and fast until a cut is started and the engine falls on its face. Indicates too little fuel, lean. Open up the high end fuel screw CCW on my Stihl saws til there is power to cut. Open up about 1/8th turn atta time til the cutting slows down a bit. At that point the air/fuel mix is just rich, which has the PH a bit cooler. Opening up the muffler (a search topic will get you there) cools the PH by letting the heat out faster.
For actual videos of the sounds of correctly tuned saws placing "tuning a saw" in the search will make available more than enough info to start you and your saw in good stead.
Mill safely
Thanks SeMo, that helps alot!
 
chunky

chunky

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I'd suggest sorting the saws oiler out before you worry about an aux oiler... That's one of the things a lot of people choose to replace with the OEM part

That's not normal for any saw & not safe... you need to properly tune the saw! Asides from the high idle, if it's running lean you'll burn it up in short order.
Thanks JD, the oiler just needed to be turned up a bit. Now I`m getting to much oil as its running off the bar. I`ll get that lined out when I get back to the cutting.
 
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