First cut

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Sent that post to quick. I am using a 3120XP on this mill and we were cutting 16" to 20" pine on the learning day. First chain I used was a skip tooth I modified to rip. Second chain wasn't a skip, but ground to rip. I had the saw tuned to 4 stroke quite nicely. I noticed though, frequently it would 4 stroke during the cut. It didn't seem to slow or bog, even though I was pushing it hard. Is this going to present a problem with this saws long term performance? I am not likely going to encounter much bigger than a 20-24" wood where I live. Did I goof and buy something to big.:msp_razz:
 
Sent that post to quick. I am using a 3120XP on this mill and we were cutting 16" to 20" pine on the learning day. First chain I used was a skip tooth I modified to rip. Second chain wasn't a skip, but ground to rip. I had the saw tuned to 4 stroke quite nicely. I noticed though, frequently it would 4 stroke during the cut. It didn't seem to slow or bog, even though I was pushing it hard. Is this going to present a problem with this saws long term performance? I am not likely going to encounter much bigger than a 20-24" wood where I live. Did I goof and buy something to big.:msp_razz:

If it's not slowing down when you push it hard then the rakers are probably too high. With a big saw like that in small wood you can afford to run a raker angle around 8.5º which will allow it to cut faster but finish might be poorer. If you would like a cutter/raker analysis of your current setup post a direct side on picture of a cutter or two.
 
Congrats on your first cuts! Personally, I don't think there is such a thing as "too big" of a saw, that said, it sounds like you will have to do a little tweaking to get the the 3120 to work harder. BobL will give you first rate critique and keen pointers on how to dial it in perfect!
 
Pictures of the cutters.

Thanks for posting the pics. Unfortunately they are a little out of focus, and the cutter also really needs to be smack bang in the middle of the photo like this for an accurate analysis.
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The two rakers in the second photo the rakers look OK, but one ow two in the first photo look too high, but I would round them over rather than leaving them flat (rounding flat rakers adds about half a degree to the raker angle anyway) Not that rounded rakers matters much in the size of wood you are cutting but they will make it a little harder for the cutter to really grab the wood. The other thing is I would clean out the gullets so the sawdust flows freely out of the cutter. I know this is easier for folks that use a file :)
 
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the frount of the guide needs rounded just a little , may make some power :dizzy:they say . The gullett needs filed smooth that lets it carry more chips . The main thing is the height of the guides seams inconsistent that makes for chatter and a rough cut .
 
Took awhile to get this posted. Just a learning day at a buds place. Took all day to cut a good piece of lumber. All fun though.

That's a sweet setup! I'm intrigued about the captive bar tip. It looks like you added this, right? What made you decide to add it? Does it help make a smother cut? On my M5 the carriage guard is aluminum and doesn't seem like it would offer much support to the tip, if I tried this. Do you find your does? Thanks.
 
That's a sweet setup! I'm intrigued about the captive bar tip. It looks like you added this, right? What made you decide to add it? Does it help make a smother cut? On my M5 the carriage guard is aluminum and doesn't seem like it would offer much support to the tip, if I tried this. Do you find your does? Thanks.

I got the idea from this thread here on Arboristsite: "Logosol owners (and CSM users in general)" by Arky217. I used it most of the day, but took it off when I changed my chain to see what diff their was. The cut was noticeably smoother with it on. Appears to be a lot of flex at the end of my 24" bar without it. Keep in mind I'm a real rookie when it comes to CSM.
 
I had not seen that thread. Helpful indeed. I'm running a 24" as well and I kind of wondered about the flex. It would be an easy enough mod to make. I'm a rook too, but thats the beauty of this site...we all progress a bit faster with this resource.
 
To analyse a cutter I copy your photos into an image processing app and mark out the purple rectangles as shown in the picture.
I then measure the width and height of the rectangle and calculate the angle between the diagonal of these rectangles and the horizontal, which is what I call the raker angle

This is the first image from your "rookie grinder technique"
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The variation in the angles is a little bit greater than I would like to see.
These angles in the small wood you are cutting would definitely not slow your saw down

This is the second
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In this one the variation in angle is too much. I try to get mine within 1º if I can.

And finally the third
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This is much more consistent.

When I sharpen I measure my raker angles directly with a digital angle finder. Of course I don't do this every time I touch the rakers. I touch my cutters up after every tank of mix and my rakers get a swipe or two after every 3-4 tanks of mix. I only measure the angles when I give chains a full sharpen in my shop.

I did not look at the the photo of your milling setup in your first post before this post and did not realise what logs you were milling and how short your bar was .
On those sizes and softness of logs I doubt you ever be able to slow that saw down unless you used a much higher raker angle than even 8.5º.
I have no idea what the optimum angle would be, I would slowly increase the raker angle over successive sharpenings and see what happens

Please bear in mind that increasing the raker angle may produce a lot of vibe and most likely a poorer finish.
It also means being very careful with that chain in any cross cutting situation as the potential for kickback increases at higher raker angles.

Before you increase the angle by grinding away the top of the rakers I would round the rakers over as this will effectively increase the raker angle
 
Another thing I noticed when looking at the photos is that these chains look new or near new and I can tell by the bottoms of the ties that they have not done much cutting but there seems to have been a fair bit of metal removed from the cutters?
 

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