New CS Mill build

[BobL]

In the first pic, the raker on the left has a flat top but the raker on the right looks like it has never been touched.

What I look at is the ratio of the distance between the cutter and where the raker touches the wood, and the raker depth.
In this picture it's the height of the yellow boxes compare to the length of the boxes.
The one on the left is ~6:1 (which is too low) while the one on the right is 12:1 and this is too high
View attachment 294577
A good working ratio is between 10:1 and 8:1 for softwood

In the second picture the raker depth is too low.

The 3rd picture is hard to judge, but the raker actually measures too high.

With the rakers so erratic the chain will be struggling to cut smoothly and could generate a lot of vibe - this will also all add to the powder dust generation.

All your cutters look like the could use a bit more hook (top plate cutting angle) - This will help the saw self feed better and reduce the amount of pushing required.

I reckon it's better to round the rakers as this reduces friction by allowing them to skate across the wood in the kerf. The corner of a flat top adds some resistance.

What concerns me more than the rakers and the TPCA is the amount of tie base wear on this chain indicating it has been pushed well beyond normal for the amount of wear on these cutters. Either the chain has been run, blunt and the CSM then pushed hard, or without oil, or both.

I was giving it a few strokes of the file at the current angle, to get the whole surface shiny metal, then giving a last couple of strokes at the lower angle like 20ish, to get closer to a rip profile. A mistake?

All that it looks like you are doing is filing a little at the tip of the cutter. You need to file at the intermediate angle all the time otherwise you will never get to the 10º TPFA.

BTW you don't need to get the whole surface shiny - all you need to do is file enough to remove the glint along the cutting edge - once the glint is gone the rest is wasted metal. Getting the surface shiny without getting rid of the edge glint is a waste of time

 

[Bongodrummer]

Bob, Thanks for the diagnosis. Lots to think on there - guess I'v got a lot to learn when it comes to sharpening :redface:

a while after that photo I sharpened it and then when over the rakers and tried to consistentify them at 6.5 degrees - I used a digital angle measure... It ended up being +- at least .3degrees though, due to fiddlyness and a few of them already being over that...

What concerns me more than the rakers and the TPCA is the amount of tie base wear on this chain indicating it has been pushed well beyond normal for the amount of wear on these cutters. Either the chain has been run, blunt and the CSM then pushed hard, or without oil, or both.

:msp_scared: I have been trying not to push it much, and sharpening between slabs. My sharpening is evidently a bit crap but I am thinking that this may be a product of limited oil on the cutting face - as I have been running canola oil and no aux... So that's definitely on the to do list...

All your cutters look like the could use a bit more hook (top plate cutting angle) - This will help the saw self feed better and reduce the amount of pushing required.

At the moment I am using a stihl file guide and a 5.2mm file.. Would I have to change to a different dia file to achieve a different TPCA? Or loose the guide?

Thanks for the forensic insights - learning lots here!

 

[BobL]

Bob, Thanks for the diagnosis. Lots to think on there - guess I'v got a lot to learn when it comes to sharpening :redface:
a while after that photo I sharpened it and then when over the rakers and tried to consistentify them at 6.5 degrees - I used a digital angle measure... It ended up being +- at least .3degrees though, due to fiddlyness and a few of them already being over that...

That's fine even +/- 0.5º is ok. Note that if you file to constant raker angle then the length of the cutters is not as important.

I have been trying not to push it much, and sharpening between slabs. My sharpening is evidently a bit crap but I am thinking that this may be a product of limited oil on the cutting face - as I have been running canola oil and no aux... So that's definitely on the to do list...

A good test if your filing is right is to slope a log and the saw and mill should cut under it's own weight ie no pushing.

At the moment I am using a stihl file guide and a 5.2mm file.. Would I have to change to a different dia file to achieve a different TPCA? Or loose the guide?

Before you do that try lets check what size file guide you are using.

 

[Bongodrummer]

Before you do that try lets check what size file guide you are using.

Oh my goodness, Bob you genius!

Double checked - file is 5.2mm Stihl brand, as I knew it was, file holder is Stihl to and says 4mm on it :jawdrop:

I can't believe I have been working most of the winter, doing a big Welsh hedgerow restoration job on my parents farm, which involved amongst other things thinning out quite a few big trees (which I now want to have a go milling). In that time I have done a lot of sharpening, been through a couple of files, got a new chain ect. I started with a file and holder given to me by my dad, checked the file was the right size and carried on.... Never thought to check the holder.
I think you just opened up a world of better sawing for me Bob!
Will pickup a correct file holder on Monday.

Cant wait to see what a difference a correct hook angle makes.. Self feeding like when the chain is new is bliss.

 

[jnl502]

Great tread everyone. Lots of good info and you can nevrer get enough learning how to get a chain in shape. Also if it has not been said a semi-cheisel will keep the cut from haveing gouge lines for the most part completely. I also have my mill to slide on my guide on every cut and make a 1" slab. Also when I make my first cut with the guide on the log it cuts a 1" to 11/2" first slab depending on how the guide lays so I never have to change the cut hight unless cutting special. Most wood just gets cut 1" for ease of drying and stacking.
jnl

 

[Bongodrummer]

Some Mods and oiler

Hi guys,
So I made some mods and sharpened the chain based on feedback here and finally got a chance to try the out the other day - a big improvement!

I added and auxiliary oiler - its a very simple affair. Was using canola oil in that and proper bar oil in the CS.

It uses a bit of super flexy silicone hose, which really conveniently just push fits into the t-slot of the profile, and stays there nice. I have it running down the vertical height adjustment and just exiting there on the bar nose at the moment. I may drill a hole near there so it can get in to the GB grove easily - not sure (opinions?). I did find without a hole I could see clearly how much oil was coming out as it was forming a rivulet along the chain as it enters the cut.

Here is the flow control. Ridiculously simple, but seems to work. As the silicon hose is so squidgy, it returns to shape even after being clamped for a long time...

One of the biggest improvements was putting a zip tie round the trigger area, which I could slide across and lock the throttle down with. Soooo much easier to control the mill, and allow adjustment of the aux oil flow on the go.

So with the chain sharpened properly, I was finding it was now self-feeding very nice. In fact, combined with the slope, I found that on the wider section I had to hold the mill back somewhat to stop it getting bogged down. This was also exacerbated on sections where the rollerblade wheel followed convex contours of the the log, as this tried to push the mill into the cut too much.

Anyway, I was getting a much smother cut this time, no big gashes in it as I didn't need to stop mid cut to refuel and I had a hand free for the wedges. The cut was a good 40-50% faster than before, though I still think the width of some of these mid-log boards (~26") was probably asking a bit much from the 440. Still I have some nice boards! :msp_thumbsup:

Got quite a large ash log up next... Trying to figure a way to join together my dad's two ladders to get a long enough guide...

 

[BobL]

. . . . Still I have some nice boards! :msp_thumbsup:

sounds like your ducks are starting to line up

Got quite a large ash log up next... Trying to figure a way to join together my dad's two ladders to get a long enough guide...

This might give you an idea.
http://www.arboristsite.com/milling-saw-mills/86081.htm

 

[Bongodrummer]

Thanks Bob. I did read that thread at some point, nice looking guide. Trouble with my dad's ladders is that they are the type where one narrower one slides in and on top of the other. They are also box rather than I profile... Should be able to come up with something though...