Depth gauges Pt3 - Is lower better?

[@michaelkearney5562]

I expected that the chain that used the progressive gauge would be quicker. It looks like I will have to rethink a few things.

[@shinichirohida2556]

A 25-inch bar with a 36RS 84dl regular sequence might be a bit too much load for a 6x cc-class chainsaw. To reduce the load on the chainsaw while using a long bar, some possible approaches are: Using a narrower gauge cutter to reduce kerf width (e.g., 23RSP) Using smaller cutters (e.g., 63PS) Reducing the number of cutters (Full Skip) Setting a shallower depth gauge (.020", 0.50mm) However, as far as I recall, 25-inch bars for 63PS were only available as hard-nose bars, so that might not be practical. If I were to focus on minimizing cutting resistance realistically, I would probably opt for a 36RSLF or a 75CJ square-ground full-skip saw chain and set the depth gauge to .020. or 33RSLF, 72CJ.

[@aussiehardwood6196]

That all makes sense for YOUR conditions in the US, it does and makes sense. But this is filmed in Australia 🦘 where most of our hardwood species will sink in water and when dry from low rainfall areas are extremely hard/dense. Stihl Australia fits ALL saws 50cc and above with .063 setups, no store even has 050 bars or chain in stock. Unless it's Picco which U suggest. Stihl offered a 20" 3/8 050 Picco setup in the US with an 8-pin sprocket as a kind of hot rod setup. I've cut smoothly with takers ground dangerously low, the chain was ruined but in some 50+ year old red gum sleeper I dug up that were underground I decided to run this chain as there was a bit of dirt in the edges of the wood. What would normally be a grabby semi dangerous experience was instead completely smooth and the chain cut quite nice. This was due to how hard the wood was, the cutter wouldn't bite deep into the wood and stall like softer wood. Semi chisel is mainly used here by 95%+ of commercial sawyers. I can badly damage a full chisel chain in clean wood in one cut off the grinder. There just isn't enough supporting metal behind the leading edge. That point just won't hold up. CL or RSLF does better. Skip works well but u are then dividing the work up between half the cutters which just means more downtime. It's just different, trust me we love our Aussie hardwoods but for fun would much rather cut what you guys do, it would make our saws look much faster 😅

[@IndianaDoug]

I don’t understand, .65mm is ~.025” which is stock raker height. So are you comparing stock height versus rakers filed with a Stihl progressive gauge at what they deem .65mm? Perhaps I’m missing something, can you explain ?

[@SawChainTheories]

@@IndianaDoug sorry this was all part of a much bigger video I didn't end up sharing because I was over it. It's a 36RS chain, filed back about 75%. Left side is set with 025/0.65mm Stihl constraint depth gauge. Right side is the same chain set with the Stihl FL progressive style gauge (like the husky/Carlton/West cost style) I was trying to work out if more (lower) is better. Tried this a heap of times in the past (7900 and 288) and they cut the same. Thought I would drop down a size to try and see a difference. Long story short - low gauges feel faster to me every time but cut about the same or worse. Carltons original idea was the cutter starts going down at some point when it filed back past the rear rivet. Lots of messing around with a dail indicator shows me this does happen but it's beyond the point of the cutter's useful life (they break off in hardwood). I still don't know if this is because of - me, the wood I'm cutting or something else. If you have done this before or try sometime in the future please let me know. Every theory and most people say it will be faster but I cannot make it work. The shape of the front of the gauge makes a much bigger difference for me compared to lowering it beyond 25 thou

[@IndianaDoug]

@ good stuff for sure, thanks. The guy I get my high end race chains from(square) has rakers set to .020” if that helps confuse you😆

[@SawChainTheories]

@IndianaDoug I have started doing the same thing. It's better for me to control the feed pressure than letting the chain pull itself in harder Just seems to work better and beats me up less in a day. Really helpful with 404

[@treelover9736]

Do u think that the results would change with a bigger saw?

[@SawChainTheories]

@@treelover9736 This is slightly unusual with how much it slowed down but some of the other ways I have tried. Dolmar 7900 16" bar - low gauge was slower by 4%. So the margin of error, they cut the same. Same result running a 25" bar on that saw. 288xp 20" - same cut speed with exl. C85 is faster with the higher gauge by a small amount. Tried with smaller saws - dolmar ps460 with both 325 and 3/8 - both prefer the higher gauge. If I try again I will use this saw and the 660 to get a feel between them. An important part of all of this, every single time I have tried this I felt it was faster with the lower depth gauge. The change in the feel of the cut was noticeable and it feels fast. Then you watch the video and see this or then cutting at the same speed and wonder why

[@treelover9736]

Thx for sharing these results :) There is a sweet spot somewhere, but it will change with a every situation. Smaller wood , type of wood, power head an so on

[@elpolaco7654]

@@SawChainTheories Must be Australian wood! Generally in all tests in papers that I have seen, increasing the depth gauges setting from the standard .025'' or .65 mm resulted in faster cutting and increased efficiency. The largest saw used was the 372 XP. Well, but the hardest wood used was beech (let's say Janka 6460 N). They certainly didn't use those nice factory side plate angles on Stihl (50°) and Husqvarna (45°) chains either...

[@SawChainTheories]

@@elpolaco7654 that's where the next part comes in, Is it just me or does this happen elsewhere? Hopefully we can get other people to try and see what happens

[@elpolaco7654]

@@SawChainTheories Of course, my above post was a bit humorous. I realize that there are so many variables involved in saw chain cutting that there is no single valid calculation model. And in fact, there is none for the chain considered as a whole. This is primarily determined by the interactions between the chain links, which have many degrees of freedom, and which do not occur in “rigid” saws such as circular saws. Researchers publishing public papers, and internally probably companies like Oregon, Stihl and Husqvarna, are aware of this. And of course many published papers contradict each other when it comes to conclusions about changes in certain parameters.