Some specifics of skip chain, saw horse power available, how each tooth draws hp, bar length recommendations for standard, semi and skip, and so on are discussed by Jake Wade a product applications engineer working at Oregon for 20 years or something like that and Glenn Lovell similar. czcams.com/video/P0TQHFDFBxg/video.html At some point Wade talks about an 'Ideal' but I can't remember his term for it. He basically talks about aiming to set depth gauges, and other tooth geometry so it functions well over a range of power availabilities/chain speeds etc. and also about specific chains and setups for specific tasks. Some interesting stuff in the vid. Cheers sincerely d
As I understand it, the conclusion here is that a skip chain puts more strain on the saw and causes a drop in revs than a no-skip. Well, I'll give it a try.... Since the distance between the same cutters (left or right) in the skip is 12 (* pitch) and in the no-skip 8, the chip thickness with the same other parameters will be 12/8=1.5 times greater. A greater depth of cut automatically means a greater load on the engine, and so can also cause a drop in RPM, which will also increase the chip thickness. That is, a positive feedback will be observed. Of course, in a no-skip chain, there will be more cutters working at the same time, but I put forward the thesis that in really hard wood, the load associated with the increased chip thickness will be more important than increasing the number of cutters in the cut piece. In all of the above, I assume that the feed force remains more or less constant and is related to the weight of the saw.
That's a good explanation of what might be occurring here. I have had mixed results with skip but for the most part it's reaction is inline with what you said. I don't have a conclusion as such, all I have really learnt over the last few days is, cutting speed is probably the least important factor in chain choice. I'm willing to leave speed behind for less reaction force and vibration, especially as the day goes on.
@@elpolaco7654 this is a hard question. I think it's official name is Eucalyptus macrorhyncha. It's commonly known as red stringy bark. The problem is there is over 900 species of eucalyptus so it's hard to be sure
@@elpolaco7654 It's definitely not the hardest of wood here. It can change dramatically tree to tree depending on where it grows. This one was on a ridge line and it's much harder than some of the others growing 300m away. The type of tree I was cutting with the 16 inch bar on the 288 is regarded as a much harder wood but had grown in the bottom of a small valley, in good soil with lots of moisture. It was much easier to cut than this
Some specifics of skip chain, saw horse power available, how each tooth draws hp, bar length recommendations for standard, semi and skip, and so on are discussed by Jake Wade a product applications engineer working at Oregon for 20 years or something like that and Glenn Lovell similar.
czcams.com/video/P0TQHFDFBxg/video.html
At some point Wade talks about an 'Ideal' but I can't remember his term for it. He basically talks about aiming to set depth gauges, and other tooth geometry so it functions well over a range of power availabilities/chain speeds etc. and also about specific chains and setups for specific tasks. Some interesting stuff in the vid.
Cheers
sincerely
d
✌✌🚀🚀
As I understand it, the conclusion here is that a skip chain puts more strain on the saw and causes a drop in revs than a no-skip.
Well, I'll give it a try....
Since the distance between the same cutters (left or right) in the skip is 12 (* pitch) and in the no-skip 8, the chip thickness with the same other parameters will be 12/8=1.5 times greater.
A greater depth of cut automatically means a greater load on the engine, and so can also cause a drop in RPM, which will also increase the chip thickness. That is, a positive feedback will be observed.
Of course, in a no-skip chain, there will be more cutters working at the same time, but I put forward the thesis that in really hard wood, the load associated with the increased chip thickness will be more important than increasing the number of cutters in the cut piece.
In all of the above, I assume that the feed force remains more or less constant and is related to the weight of the saw.
That's a good explanation of what might be occurring here. I have had mixed results with skip but for the most part it's reaction is inline with what you said.
I don't have a conclusion as such, all I have really learnt over the last few days is, cutting speed is probably the least important factor in chain choice. I'm willing to leave speed behind for less reaction force and vibration, especially as the day goes on.
@@SawChainTheories What species of tree is this, if you don't mind me asking?
@@elpolaco7654 this is a hard question. I think it's official name is Eucalyptus macrorhyncha.
It's commonly known as red stringy bark. The problem is there is over 900 species of eucalyptus so it's hard to be sure
@@SawChainTheories Thank you. It's hard to be sure about the species, but I'm pretty sure this wood must be really hard...
@@elpolaco7654 It's definitely not the hardest of wood here. It can change dramatically tree to tree depending on where it grows. This one was on a ridge line and it's much harder than some of the others growing 300m away.
The type of tree I was cutting with the 16 inch bar on the 288 is regarded as a much harder wood but had grown in the bottom of a small valley, in good soil with lots of moisture. It was much easier to cut than this