slow going milling
- Thread starter Rosss
- Start date
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Well those rakers look pretty good to me. Im surprised it took 20 minutes for your cut. There must be something else going on with your mill other than the saw chain chain
This one has a angle of ~7.5º. That's the angle the red line makes relative to the bar.
Note how the raker angle is really from the edge of the cutter, to the top of the raker a straight line rotated about cutter edge first makes contact with the raker.
This is because the whole cutter rocks back when it makes contact with the wood.
This one 6.4º
The tolerances of the photographic base measurements is probably +/- 0.5º so they may not be 1º different.
About the only thing one might try is add a touch more hook to the top plate cutting angle. This is easy if you are using a grinder -
if you are filing by hand it's harder but not impossible.
There are various threads around about how to do this.
This one has a angle of ~7.5º. That's the angle the red line makes relative to the bar.
Note how the raker angle is really from the edge of the cutter, to the top of the raker a straight line rotated about cutter edge first makes contact with the raker.
This is because the whole cutter rocks back when it makes contact with the wood.
This one 6.4º
The tolerances of the photographic base measurements is probably +/- 0.5º so they may not be 1º different.
About the only thing one might try is add a touch more hook to the top plate cutting angle. This is easy if you are using a grinder -
if you are filing by hand it's harder but not impossible.
There are various threads around about how to do this.
This is a chain i put aside as it was cutting slowly, or i thought it was.
I put a new bar on and this chain.
I finished a cut that had been started and did the last foot.
I then started the next layer and it had no bite, seemed to take a long time just to get enough cut to get the bar all the way into the log. Didnt want self feed, more would have been me pushing.
Before starting, had a visit with ghe machinist who lives two doors down from the house where the log is.
Talked about the different ways the mill could be out of alignment. Not super obvious except it looks like one of the uprights is off 90 a bit, but that doesnt acount for lack of cut.
I have 3 chains and all have grown slower after use and sharpening by me. By use i am describing milling a few logs.
I will be going over the mill to check alingments.
Going to try a few cuts with the saw with out the mill on it.
It doesnt seem to pull as hard against the log in the cut milling as it did.
Also going to try a regular chain and see how that goes in the mill.
Adamant
ArboristSite Lurker
The bar does look like it has a burr, so it prob needs dressing.
Also there seems to be inconsistent lengths of cutters, which may indicate inconsistent sharpening technique .
Also there appears to be some rounding over of the top plate cutting edge corners. This could lead to the cutters not biting like they should (until filed or ground back to a full clean no-glint edge). Might also indicate dirty/sandy wood/bark which would make the chain dull much quicker than usual.
Check chain is not over tensioned and is oiling properly.
Make sure of consistency with sharpness and in my opinion angles of left and right cutters needs to be equal. Btw, different lengths of cutters doesn't matter if raker depths are set by angle per BobL's method.
I see there was another thread on here where a user commented on the different sharpening angles on laser rip chain being annoying/tedious to sharpen so maybe there is something there too,
or you could just not be clearing material out of the kerf properly because of the 0deg top plate angle - I'm with Bob at 10deg.
Also there seems to be inconsistent lengths of cutters, which may indicate inconsistent sharpening technique .
Also there appears to be some rounding over of the top plate cutting edge corners. This could lead to the cutters not biting like they should (until filed or ground back to a full clean no-glint edge). Might also indicate dirty/sandy wood/bark which would make the chain dull much quicker than usual.
Check chain is not over tensioned and is oiling properly.
Make sure of consistency with sharpness and in my opinion angles of left and right cutters needs to be equal. Btw, different lengths of cutters doesn't matter if raker depths are set by angle per BobL's method.
I see there was another thread on here where a user commented on the different sharpening angles on laser rip chain being annoying/tedious to sharpen so maybe there is something there too,
or you could just not be clearing material out of the kerf properly because of the 0deg top plate angle - I'm with Bob at 10deg.
Thanks for the input.
The length of the scoring cutters and the clearing cutters on the chain is quite different. The two teeth that are referenced by Bob for raker angles are both scoring teeth. I was trying to set up the pictures from my cell phone so I couldn't see clearly see the details of what I posted. I had wanted to include pics of both kinds of teeth.
I am wondering if the rakers for the clearing teeth are not where they need to be height wise.
This is normal for newbies until they get their sharpening technique sorted.
Yep that's what I would do - back to basics - it will be easier to diagnose problems.
Milled the same log with a new semi chisel chain. Took 9 minutes for 7.5 feet.
I was satified with the result finish wise. Not as nice as the milling chain finish(when it works)
The mill is still not quite right. I need to spend some time with it and or make some new rails for it.
I used 1 inch square aluminum with 100 guage wall. Thinking I should move to more solid stock.
I am appreciating the support and advice
I was satified with the result finish wise. Not as nice as the milling chain finish(when it works)
The mill is still not quite right. I need to spend some time with it and or make some new rails for it.
I used 1 inch square aluminum with 100 guage wall. Thinking I should move to more solid stock.
I am appreciating the support and advice
Is that with the 10º Top plate filing angle? If not that should improve the finish
Try dropping the rakers on the new chain by a) 3 swipes, b) try cutting, and repeat a & b until the chain starts being too grabby.
Then file the cutters back - maybe 10 swipes and measure the raker angle with a DAF.
That's your optimum raker angle for that saw/chain/cut width/wood type.
I left it stock to try it that way before doing anything to it.
I need to find a daf. So far locally they all seem to be the kind that have two arms and scissor.
I have several DAFs, the latest one I bought at Lee Valley in Calgary is called a Tilt Box.
I see you are in Edmonton where there is also Lee Valley Store.
http://www.leevalley.com/us/wood/page.aspx?p=67350&cat=1,43513
Don't be tempted by cheaper eBay ones, they either chew batteries or go out of whack the first time they are dropped.
Wixey are another good brand of DAF.
I see you are in Edmonton where there is also Lee Valley Store.
http://www.leevalley.com/us/wood/page.aspx?p=67350&cat=1,43513
Don't be tempted by cheaper eBay ones, they either chew batteries or go out of whack the first time they are dropped.
Wixey are another good brand of DAF.
