Water or oil for bar tip lube on CSM?

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The primary idea behind an Aux oiler is to reduce B&C wear and to a lesser extent take some load off the powerhead. I have a temp gauge on my powerhead and found that water lube did not reduce the powerhead temp any more and maybe less than oil. The only benefit I found was that I could touch the B&C sooner and yes it does keep the chain cleaner but so does using enough aux oil.

I have milled some 30 Aussie hardwood logs (most would be harder when green than Hickory is dry, as well as being very gummy) using water cooling in place of Aux oil and found the B&C wear was a clear problem. I also tried hooking up a running hose to the aux oiler point so I could use larger amounts of water and it made no difference - if anything it was worse.

The analogy with the tool steel cutting is not valid as tool steel does not constantly slam up and down against a workpiece like a chain does on a bar. Most people don't realize that only about every 3rd cutter on a chain takes a significant bite into the wood and this lifts a short segment of chain up off the bar. The biting cutter rocks it's way further into the wood until the tension on the chain builds up so much the leading cutter tears out the chip and the chain slams back down onto the bar. Water cannot sustain these sorts of pressures and is quickly squeezed out between the B&C dragging any regular bar oil with it.

All good points sir although my experience with 2 strokes and the type of "metering" carburetors they use shows that a cylinder or head temp gauge can be essentially useless. But that's another thread for another day, based on my experience with air cooled engines operating on the restricted throat principal. So assessing the load the engine is seeing based on temperature is very unreliable.


Now I totally and whole heatedly agree with your points above about water, so I want to clarify that I am not talking about plain old' water. But rather water that has special additives dissolved in it, that give it lubricating properties far superior of any oil. While cooling at the same time.

Here is my thought process, milling puts excessive amounts of long term friction into a bar and chain which results in heat build up, causing the chain to stretch as it expands and the bar to swell closing the gap the chain rides in. This all causes the designed tolerances for each part to change, changing and reducing the ability of the parts to hold oil and be lubricated properly and the oil to break down reducing its effectiveness. If you keep the moving parts cool they will operate as designed, which is what the water does. But that in turn removes the oil which lubricates. Water caries heat away better than oil. Water is plentiful. Water does not lubricate. But, there are additives available which allow it to do so and are safe to use.

My idea is to do away with oil completely, as with the machining analogy, and only use a lubricating water based coolant. The stuff in have in mind cost about $45 a gallon. One gallon mixes to 50 gallons with water. I this biodegradable, environmentally friendly. And ever year our supplier rep replaces the oil in a 16 HP generator and runs it at full load with the water coolant mix for an hour just to show its abilities to us. Something we all look forward to every spring.
 
although my experience with 2 strokes and the type of "metering" carburetors they use shows that a cylinder or head temp gauge can be essentially useless.
My temp gauge is not attached to the cylinder head, it is attached to the exhaust port. More importantly I also have a tacho on my powerheads. When a power head is fully warmed up and mill is cutting on a slope under its own weight with most of the bar buried in the log, if I turn off my Aux oiler off, rpms goes down, turn on aux oiler revs goes down. That's clear enough for me.

Here is my thought process, milling puts excessive amounts of long term friction into a bar and chain which results in heat build up, causing the chain to stretch as it expands and the bar to swell closing the gap the chain rides in.
The gap does not close - it expands and being made from similar material so does the chain so the amount of clearance will stay more or less the same. The friction comes from the chain rubbing on the wood, the chain rubbing on itself, the chain slamming down onto the bar and the chain rubbing on the rails and sprockets. An examination of a chain that has been pushed hard without adequate lubrication will show via visible bluing the greatest temperatures and wear are experienced by the base of the cutters. There is a, not unreasonable, expectation that this wear is cause by sliding friction of the chain on the bar. If this was the case base of the cutters would be totally flat and smooth but this is not the case. A closer examination will show the wear is a mix of flat smooth and rounded peening cause by the cutter base slamming down onto the bar rails. The same applies to the bar - simple sliding friction will wear the bar rail smooth with little or no burring. Instead the bar rails can develop large burrs and preferred wear (large dips in strange places on the bar) related to chain harmonics which are determined by chain and bar dimensions and chain tension. Even a small amount of oil will handle the sliding friction but no water additive that I know of will handle the friction cause by chain slamming.

And ever year our supplier rep replaces the oil in a 16 HP generator and runs it at full load with the water coolant mix for an hour just to show its abilities to us. Something we all look forward to every spring.
Chalk and cheese. A generator is not a B&C. Well made engines need relatively little oil to run because by far the greatest fiction is sliding friction so a monolayer of oils is all that is needed between surfaces. Even a CS powerhead needs very little oil to stay lubed which is why they can be run on a ratio of 100:1 on fully synthetic lube.

Chains need a a higher pressure tacky oil that can withstand the constant slamming of the chain onto the bar and to remain on the chain as it goes around sprockets. The degree of slamming that takes place inside a well made engine is minimal compared to a B&C.

I know the machining lube stuff you are referring about and it too will not do anything for slamming. To be analogous in the machining sense the machine tool would have to be slammed over a distance of 1/8" back and forth into the the work at the rate of ~150 times a second.
 
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Where did you get this information?

Shaun

The Carlton chain guide is one of the few documents around that describes how a chain really works. If you also look closely at the non-cutting end of the bar you can sometimes see the "chain porpoising" wave propagating backwards out of the cut. BTW it doesn't do this when noodling as the cutters are cutting with the grain and there is little cross grain cutting and what there is, is at a very shallow angle. Cross cutting and milling is where the chain does this porpoising action.
 
Well Bob I'm gonna try it any way. You make some valid points and I appreciate your clarification and explanations. But I'm not talking about cheap coolants used for turning a piece of brass into a punch. I cut and grind most grades of tool steel (d, t, s, 4140 in the hardened state, tungsten carbide) on a daily basis. I understand what you are saying about the chain chattering and bar harmonics. Every object has a certain frequency. I have one of those think outside the box gotta try it just to know minds. I've made a living alone just by thinking up ideas and solving problems and she something fails ya just have to figure out exactly why and sometimes watching it happen is the best way. Worst case I fry a bar and chain. I have some worn stuff laying around so no lose if they go to junk. In my mind, a chain moving at 65 ft/s chattering over some wood is nothing compared to a 16 inch surfacing mill jumping an 1/8 over a 60 inch diameter tool bed at a tip speed of 230 ft/sec and a feed force around 300 lbs. To me the wood and chain chatter seem like cutting butter. Personally, I feel that the sharpening angles of a chainsaw need to be thought over once again. Much could be gained if one where to put the time and effort into working out the chatter issue. It could be done with multi-angle grinding.


I don't want this to be an argument. We each have our own opinions and i most certainly respect your experience. Your rig has inspired mine. I take your advice whole heartedly. But what do I really have to lose if I'm safe about everything and have some guards in place should there be a chain failure. Worst case scenario, I have one more story to share over a few guiness' out by the campfire.
 
Well Bob I'm gonna try it any way. You make some valid points and I appreciate your clarification and explanations. But I'm not talking about cheap coolants used for turning a piece of brass into a punch. I cut and grind most grades of tool steel (d, t, s, 4140 in the hardened state, tungsten carbide) on a daily basis. I understand what you are saying about the chain chattering and bar harmonics. Every object has a certain frequency. I have one of those think outside the box gotta try it just to know minds. . . . ..

I have no probs with people trying out stuff for them selves. I also tried water cooling against advice and like I said I was not satisfied until I had milled 30 logs with it. :msp_smile:
 
It seams to me the hammering is going on up in the head of the mill not at the coolant . The oil in the head is thick like 10 or 15 wt would make good bar oil ? The porpoises that breaks the chip you will long strings that the chain can't clear .Its explained better in Carltons guide ,also in chainsaw lumbermaking by Will Malloff .
 
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water or oil

I have been using used auto trans oil in my mill since I built it.with no problems so far 2 years with the same bar 320 hrs , get the oil from my buddy that has a auto repair shop
 
Yes, use bar oil lubricant. Water will make the bar rust and it will do severe damage to the chain and bar that you will not like.
 
Yes, use bar oil lubricant. Water will make the bar rust and it will do severe damage to the chain and bar that you will not like.

I milled about 30 logs using water in the aux oiler and standard lube in the saw and didn't have a problem with rust. The way I did this was at the end of the day remove the water cooling and run the saw WOT for about 20 seconds so that everything got covered in B&C oil. If I did not do this then it would definitely rust - this tells me the water washes the oil off. Of course I was use straight water and not a water oil mix.
 
Well Bob I'm gonna try it any way. You make some valid points and I appreciate your clarification and explanations. But I'm not talking about cheap coolants used for turning a piece of brass into a punch. I cut and grind most grades of tool steel (d, t, s, 4140 in the hardened state, tungsten carbide) on a daily basis. I understand what you are saying about the chain chattering and bar harmonics. Every object has a certain frequency. I have one of those think outside the box gotta try it just to know minds. I've made a living alone just by thinking up ideas and solving problems and she something fails ya just have to figure out exactly why and sometimes watching it happen is the best way. Worst case I fry a bar and chain. I have some worn stuff laying around so no lose if they go to junk. In my mind, a chain moving at 65 ft/s chattering over some wood is nothing compared to a 16 inch surfacing mill jumping an 1/8 over a 60 inch diameter tool bed at a tip speed of 230 ft/sec and a feed force around 300 lbs. To me the wood and chain chatter seem like cutting butter. Personally, I feel that the sharpening angles of a chainsaw need to be thought over once again. Much could be gained if one where to put the time and effort into working out the chatter issue. It could be done with multi-angle grinding.


I don't want this to be an argument. We each have our own opinions and i most certainly respect your experience. Your rig has inspired mine. I take your advice whole heartedly. But what do I really have to lose if I'm safe about everything and have some guards in place should there be a chain failure. Worst case scenario, I have one more story to share over a few guiness' out by the campfire.
bumping to ask how this worked out
 
The primary idea behind an Aux oiler is to reduce B&C wear and to a lesser extent take some load off the powerhead. I have a temp gauge on my powerhead and found that water lube did not reduce the powerhead temp any more and maybe less than oil. The only benefit I found was that I could touch the B&C sooner and yes it does keep the chain cleaner but so does using enough aux oil.

I have milled some 30 Aussie hardwood logs (most would be harder when green than Hickory is dry, as well as being very gummy) using water cooling in place of Aux oil and found the B&C wear was a clear problem. I also tried hooking up a running hose to the aux oiler point so I could use larger amounts of water and it made no difference - if anything it was worse.

The analogy with the tool steel cutting is not valid as tool steel does not constantly slam up and down against a workpiece like a chain does on a bar. Most people don't realize that only about every 3rd cutter on a chain takes a significant bite into the wood and this lifts a short segment of chain up off the bar. The biting cutter rocks it's way further into the wood until the tension on the chain builds up so much the leading cutter tears out the chip and the chain slams back down onto the bar. Water cannot sustain these sorts of pressures and is quickly squeezed out between the B&C dragging any regular bar oil with it.
Do you have a link for the temp gauge on the powerhead? Seems like a great idea
 

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