Whats causing this?

[Woodworks]

Milling up a few boards of scotts pine and get these ripples from the chain in patches yet other areas are smooth. Evenish feed speed and feels the same when cutting where it's happened. No difference before and after sharpening

[wisewood]

Milling up a few boards of scotts pine and get these ripples from the chain in patches yet other areas are smooth. Evenish feed speed and feels the same when cutting where it's happened. No difference before and after sharpening

 

That's weird!

It's called wash board effect but never seen it so pronounced in one area like that. Usually caused by using crosscut chain instead of milling chain.

What chain are you using? gransberg milling chain with the modified scorers gives the best results.

I wonder if the slab is sagging/dipping down slightly at that point, making the bar tilt.

Maybe check the surface with a straight edge or a level.

[se7enthdevil]

i always assumed its blunt blades as you get it on bandsaws too but it could be too fast a feed speed or just some sort of resonance?

[shendy]

Were you cutting thin boards and was the wood vibrating

[Woodworks]

Blade definitely sharp and it is similar to what sometimes happens with a bandsaw but have had that with new blades as well. Was cutting 1" boards. No obvious vibration but wouldn't swear there wasn't.

[Woodworks]

That's weird!

It's called wash board effect but never seen it so pronounced in one area like that. Usually caused by using crosscut chain instead of milling chain.

What chain are you using? gransberg milling chain with the modified scorers gives the best results.

I wonder if the slab is sagging/dipping down slightly at that point, making the bar tilt.

Maybe check the surface with a straight edge or a level.

 

Oregon milling chain. Started off flat after first cut but may of developed a bit of a sag as I went down through the log. It's only for a making a few sheep hurdles so wasn't checking but would like to avoid this in future.

[Jamespepperpot]

I had this with a Oregon ripping chain, it was about half way through its life and was pretty hawksbeaked due to the grinding stones on the sharpener getting smaller and me not correcting it. I was starting to get it to cutting properly and then wrote it off on a 6 inch nail. Never got it back to cutting efficiently after that.

Although it's strange how it's just a small patch on that board

[skc101fc]

Hi, I've also had this effect from my lucasmill slabber. It was actually more pronounced when using the correct hyper-skip milling chain than my own doctored standard chain. Anyway the long and short of it is, I can expect to see this washboarding if I'm putting too much pressure on trying to speed the cut, often a succession of patches like this interspersed with normal cut texture.

 

Sent from my GT-I9195 using Arbtalk mobile app

[Woodworks]

Hi, I've also had this effect from my lucasmill slabber. It was actually more pronounced when using the correct hyper-skip milling chain than my own doctored standard chain. Anyway the long and short of it is, I can expect to see this washboarding if I'm putting too much pressure on trying to speed the cut, often a succession of patches like this interspersed with normal cut texture.

 

Sent from my GT-I9195 using Arbtalk mobile app

 

Sounds similar. Will try slower next time but not forcing and felt good but clearly something wasn't right.

 

Sharpening wise I am using a guide like in the picture but at 10 degrees not 30. Presume the hook angle is the same as a crosscutting chain?

[Jamespepperpot]

 

I couldn't find a better picture but this kinda explains it. Although if you're sharpening with a normal file it would only happen if you were filing the bottom of the tooth rather than keeping the same profile so I doubt this is the problem - I don't 100% know that it was mine but it was the only thing I could see wrong on mine. It cut pretty fast though.

More common with electric grinders as the stone shrinks in size when used