Scaley

[Joe Luzich]

First post and it has to be a problem. I am finish turning a maple bowl. The bowl is smooth except for a fish scale affect on the inside and outside in spots. I sharpened the gouges, same affect. I used a scraper and a sheer scraper, same fish scales. I even went to a 60 grit gouge and still can't get rid of the scaley finish. Has anyone seen this on any of their turnings and how do I get rid of it. I hate to loose this bowl, it has a nice grain pattern.

[Ted Calver]

Joe,
It would help if you could post a couple of photo's of the problem. If you are turning a large bowl without a bowl steady you could be getting some flexing and chattering that might make such a pattern.

[Bob Hovde]

[QUOTE=fish scale ??[/QUOTE]

Joe,

By "fish scales" do you mean light (white) spots? I get them on some woods after a catch that makes the tool bounce. I have assumed the wood has been bruised fairly deeply, making it hard to sand out the error. I guess the solution is to practice more to reduce bounces. Now, if I can just find the time to practice more...:D

Bob

[Jim Becker]

Chatter, perhaps, due to uneven density in the blank which makes it out of balance, despite it probably being round....OR...due to vibration in the machine.

[Ken Grunke]

I spent at least a couple hours messing around before I was able to get it to disappear, using a variety of tools in shear-scraping mode. Very light passes with a sharp tool, over and over again was the only way.
This is Maple, not sure what kind but it's fairly soft--NOT sugar maple.
46785
One thing I did that must have helped a lot was wet it down with polyurethane first, and shear scrape while still wet. Shellac or sanding sealer would have been better, but I didn't have them.

[Stephen Hibbs]

It looks like you have what is called "tearout" run a search for it and you will find lots of discussion about how to get rid of it. I use the 60 grit gouge with light pressure, others use sanding sealer and such.

[Joe Luzich]

Thanx for all the help. I about tried them all but still could not get rid of it. I think it may be a defect in the blank. I looked at the other half of the log that was still drying and I could see a little in the roughed out stage. Thanx again.

Joe

[Ted Calver]

Joe,
Another possibility to consider. The pattern in your photo looks similar to the pattern in a piece of walnut I had on the lathe last night that had been dropped by a hurricane in 2004. The piece had what is called ring shakes--where, among other things, some traumatic event makes the wood start to separate/shear along the growth rings. You might try a google search for a better explanation. Such wood can unexpectedly fly apart and is generally not recommended for turning (although I'm going to apply lots of CA to the walnut and see what happens).

[Ken Grunke]

Ted, the photo is mine, which I posted in reply to Joe's post to let him know I may be having the same problem and how I dealt with it.
The wood I turned this bowl from was straight grained, and had no apparent defects--there are a couple other guys in my local AAW chapter who scored the same wood so I'm waiting to see if they have the same problem. Saturday AM is our monthly meeting, we'll exchange notes.
I'll post this finished bowl here as soon as it's, well, finished :-) -- maybe tonight.

[Ken Grunke]

Well, here is the finished bowl, took me longer than I had figured. There's still a tiny bit of that "scaley" look on the inside that Joe referred to, but the polyurethane helped to blend it in somewhat.
47218

I have another roughed out piece of the same wood in the FREEZER of all places--I boiled it last week and stuck it in there. My plan is to turn it while still frozen, to see if that helps with the tear-out.