Grain direction and chipping

[GaryMGg]

In relation to this topic, http://www.penturners.org/forum/topic.asp?TOPIC_ID=21793, I was thinking about it some more early this morning.

Last night while working on a DIW pen for a client, I noticed that the gouge wanted to chatter when the lower barrel was on the mandrel so that the nib end faced left.
And, it really didn't matter if I was shaving right-to-left or left-to-right.
I flipped the barrel 180 on the mandrel, and no more chatter.

I've noticed this several times on different woods.
I know which way the grain runs determines the direction a board should be planed.
Is this the same effect being seen on the lathe?
Could that be partially contributing to the chipout Marc is having?
Has any one else observed this and flipped a barrel to obtain a smoother cut?

- G -

 

[Dario]

Gary,

Yes the grain direction affects how a wood is cut. Normally if you cut towrds a supported grain, it is fine but not the other way. I don't reverse the tube but reverse my cut direction. Note that when reversing cut ...you have to flip the tool too.

In Marc's case...the problem is the curly wood IMHO...thus the wood changes grain after a few mm so it is difficult to know when to change direction. Best way is to really take as little wood as possible so it won't chip out. Planing cut with a skew does this very well.

Applying thin CA also helps since it will stabilize that area and if done properly, should cut evenly no matter how the grain direction is.

If all else fails, then sanding earlier is the best next action.

 

[RussFairfield]

Adding to what Dario said, you will get less chipping with the tool that is the least sensitive to grain direction - a sharp skew.

 

[Marc Phillips]

I am pretty much convinced that it was just some really unruly maple... dug out the scrap piece that the bands were cut from and there is some gnarly grain there... and the wood feels really light... as in super-dry...

I use the skew equally poorly in both directions [] ... but I didn't intentionally check the chipout improvement by cutting a different direction and then checking the blank.. Just kidding actually... I am comfortable with the skew and use it most of all the tools....

I think it was just some nasty wood.... heaven knows it couldn't be the skill of the operator!! [:I]