What causes the tool marks in bowl turning, specifically in the end grain part of a bowl: the parts that come around twice each rotation. To be clear the face grain is perpendicular to axis of lathe. The tools cause it I know, but ways to avoid? Final Cut is a push cut with a 5/8 bowl gouge, plenty sharp I think but could be wrong.
-
Congratulations to Rick Moreton, People's Choice in the July 2025 Turning Challenge (click here for details) -
Welcome new registering member. Your username must be your real First and Last name (for example: John Doe). "Screen names" and "handles" are not allowed and your registration will be deleted if you don't use your real name. Also, do not use all caps nor all lower case.
Tool marks on end grain
- Thread starter Paul Durden
- Start date
- Joined
- Feb 28, 2021
- Messages
- 1,667
- Likes
- 1,454
- Location
- Roulette, PA
- Website
- www.reallyruralwoodworks.com
Practice, practice, and more practice is pretty much the solution - You're most likely getting burnishing tool marks which are caused by actually rubbing the bevel as you cut - In reality, one should FLOAT the bevel (Bevel barely touches wood, so softly that the wood doesn't know it) and achieving that does take rather a bit of practice (as well as sharp tools - If you can't start and continue a cut without pushing edge into wood, the tool ain't sharp enough.... should be able to rotate wood by hand and touch edge to wood with other hand, following bevel, and it should slice cleanly with little to no effort involved - that kind of sharp...)
I’ve ran into something similar to this, but I use carbide tools.
The speed you use and the “touch” you have seems to make all the difference!
The speed you use and the “touch” you have seems to make all the difference!
- Joined
- Apr 27, 2004
- Messages
- 9,245
- Likes
- 5,905
- Location
- Lakeland, Florida
- Website
- www.hockenberywoodturning.com
I assume you are referring to the back side of the endgrain
This is tearout from a tiny bit of unsupported cut fibers.
Sharp tools, high shear angle, light cuts all help to reduce this.
As the end grain comes around the first 1/2 has long fibers behind supporting a clean cut.
The next part of the endgrain has shorter fibers behind making the area prone to tearout
This may help to show what I described
Last edited:
A very sharp, smaller bowl gouge will help. I use a 3/8" Ellsworth grind for finishing cuts. Sometimes a 1/2", but almost never with my 5/8".
A freshly sharpened bowl gouge and a push cut from the rim to the bottom kissing the bevel. As soon as you lift the bevel off you get tear out. For me size of gouge doesn’t matter.
I had a mentoring day with one of our guild members yesterday. It is indeed tear out from endgrain. it can be resolved with a sharp, really sharp bowl gouge. My bowl gouge was only sharp until I compared it to his. Better if resolved before sanding.
I usually use my bowl gouges straight off a 180 grit CBN wheel, but if I'm having trouble with a clean finish cut, I've found that honing the edge can help. I use a small superfine diamond/ceramic hone from Eze-Lap (model CD4).
Any time you are cutting against/into unsupported end grain, like on the bowl, you will get tear out. Some woods are better at having less, mostly denser woods, and some woods, mostly softer ones, are horrible like cotton wood. Some times polishing/stropping the flutes after sharpening helps, some times a higher grit CBN wheel helps, some times you just have to resort to the 80 grit gouge/abrasives. I have not yet taken one of my tools and sharpened them to the level of my bench chisels or plane irons. Some day....
robo hippy
robo hippy
Yup ,its kinda horses for courses. Lol, I often suggest that beginners use Pinus Radiata to learn. The promise is if you master this pine you will be a master of not only technique but also of sharpening.
Dave Landers
Beta Tester
The other thing I do is try different gouges and/or different presentation of a gouge. Sometimes, a piece will respond well to a shear cut, other times not. Sometimes it wants a push cut. Sometimes it's a 40º gouge. Sometimes a negative rake scraper. But always light cuts with a sharp tool.
I will go over a problem area with light experimental cuts until I find the gouge/presentation that yields a surface I'm happy with. And especially with problem wood, it's not always the same for the entire piece.
In the meean time, while you work on your “no tool marks” skills, shear scraping with a scraper or long wing bowl gouge can clean them up. Try shear scraping moving in both directions and observe which direction works best for the current wood. Also, hand cabinet scrapers (lathe off) can do a nice cleanup as well.
Tool marks might be caused by the heel of the gauge, especially with 50 degree or more bewel. Please see if the bewel heel touches the wood and leaves the marks.
Easy solutions - add secondary bewel to the gauge, basically grind away the heel. We only need about 2-3mm of the main bewel, the rest can be safely removed. It works especially well on the inside of the bowls. Another solution - use steeper sharpening angle, ie. 40-45 dergee.
PS. - the above comes from videos of Tomislav Tomasic Woodturning, a Chroatian turner who's IMHO great source for begginner turners, and who's mentor is Richard Raffan.
Tomislav Tomasic Woodturning
Easy solutions - add secondary bewel to the gauge, basically grind away the heel. We only need about 2-3mm of the main bewel, the rest can be safely removed. It works especially well on the inside of the bowls. Another solution - use steeper sharpening angle, ie. 40-45 dergee.
PS. - the above comes from videos of Tomislav Tomasic Woodturning, a Chroatian turner who's IMHO great source for begginner turners, and who's mentor is Richard Raffan.
Tomislav Tomasic Woodturning
Last edited:
That's an easy one to try I'm ground at 50 degrees actually, so I can try grinding off the heel. Thanks for the suggestion
BTW, I always follow gouge cuts on face turnings with a curved NRS to remove tool marks and tiny end-grain tearout. Then use hand scrapers before hand sanding.
I've watched a lot of Tomislav's videos, and learned a lot from him. I like his style... explaing rather that just showing off what he can do.Tool marks might be caused by the heel of the gauge, especially with 50 degree or more bewel. Please see if the bewel heel touches the wood and leaves the marks.
Easy solutions - add secondary bewel to the gauge, basically grind away the heel. We only need about 2-3mm of the main bewel, the rest can be safely removed. It works especially well on the inside of the bowls. Another solution - use steeper sharpening angle, ie. 40-45 dergee.
PS. - the above comes from videos of Tomislav Tomasic Woodturning, a Chroatian turner who's IMHO great source for begginner turners, and who's mentor is Richard Raffan.
Tomislav Tomasic Woodturning
Count me another big fan of Tomislav (and of course his mentor Richard Raffan). I also think his accent is cool. His back-hollowing technique is on my agenda to try as soon as I work up the courage. I can just imagine the catch if you get off the bevel!
Aaron, I did see a video where Richard explained that cut. He commented that most important thing is to not try to cut with the nose. At present, I use a drill in some vice grips, and drill to depth first, then hollow out the rest. I do keep my spindle detail gouge on the tool rest rather than up high. I am getting better at it....
robo hippy
robo hippy
Hey, have you ever used the drill dept stops, such as collars like this?
Amazon.com: Professional Stop Collar Set - Drill Bit Depth Stop - 8 Piece Kit (1/2”, 7/16”, 3/8”, 5/16”, 1/4", 7/32”, 3/16”, 1/8”) Superior Aluminum Split Ring Design : Tools & Home Improvement
Amazon.com: Professional Stop Collar Set - Drill Bit Depth Stop - 8 Piece Kit (1/2”, 7/16”, 3/8”, 5/16”, 1/4", 7/32”, 3/16”, 1/8”) Superior Aluminum Split Ring Design : Tools & Home Improvement
www.amazon.com
I often use them for fairly shallow depth holes. I have a couple of drill bits mounted in wooden handles. Set the collar to the depth I want, tighten the set screw, hold the bit by the handle and push into the wood while the blank is spinning until the stop collar contacts the surface. Very quick, repeatable.
Sort of. I use a piece of rubber hose or clear tubing about 1/8” long that stretches over the bit. Just move it to the needed depth.
- Joined
- Apr 27, 2004
- Messages
- 9,245
- Likes
- 5,905
- Location
- Lakeland, Florida
- Website
- www.hockenberywoodturning.com
Just go for it. If you can find a local turner to show you it makes it easier.
Saw a Raffan demo went home and tried it
I had a few non catostrophic catches learning it mostly from angling the nose too far towards the wall.
Coming out on the side wall I cut with the wing pulling nose so the nose isn’t cutting.
I like using a spindle gouge with a finger nail grind. The wing has a nice curve to the tip
Drill a hole. Opened it up.
Last edited:
Thanks for the encouragement, Al-My usual approach to any new daunting challenge in wood-turning (or really in every aspect of life) is to stew on it for awhile before suddenly giving myself a pep-talk that goes something like "Man up, you ******* *****" (use your imagination), and then I do indeed just go for it. I can see this making lidded boxes much easier especially.
Some of you guys are also encouraging me to try feet on bowls; I especially like them on live-edge bowls. Always something new to learn. Speaking of which, I'm out the door here in a few for Matt Monaco's platter class at John C. Campbell: I'm ready to up my platter game. Anyway, y'all enjoy a break from me!
Well, if I used a drill depth stop, since every piece is different depths, it would take forever. I do like Doug's idea of using a piece of hose. Now, to find a piece to match my drill bit....
robo hippy
robo hippy
The metal depth stops I use are split rings loosened and tightened with an allen head screw, stored in a shallow drawer with the allen key. Adjusting one takes me about four seconds.
Since I hold the bits by the handle and drill with the wood spinning (slowly) setting the depth and drilling the hole is very quick.
EDIT: This is what I keep near the lathe. I think the set I got had five sizes.
BTW, I never use this method when I need a precisely centered hole - only to set depth for hollowing.
I also don't use the depth collars with a drill bit in the tailstock - for non-critical depth holes I make a mark on the bit with a red sharpie or a bit of tape.
@Ted Pelfrey showed another method to drill precise shallow depth holes for use when carving. (The depth looked to be maybe 3/16" or so.) He found a suitable split roll pin at the hardware store that fit snugly over a small diameter drill bit. It looked tight but could be adjusted as needed. When carving one piece he drilled multiple shallow depth holes inside one shape before using a rotary bit to cut away wood so the bottom of that area was uniform. Nice idea. I took notes.
JKJ
Last edited:
- Joined
- Apr 27, 2004
- Messages
- 9,245
- Likes
- 5,905
- Location
- Lakeland, Florida
- Website
- www.hockenberywoodturning.com
Enjoy Campbell
What a great place.
If it's not too late to read this: if you haven't been there before, make SURE to take a break and walk around and visit some of the other shops: carving, blacksmith, fiber arts, paper making, glass, jewelry, painting, stone, etc, etc, etc, especially after the evening meal. Some of the most enthusiastic people spend their evening off-times in the shops. I've met so many wonderfully creative students and instructors that way.
And the grounds are beautiful. And the food great. Hold me back...
JKJ
Dave Landers
Beta Tester
I do the same but use an O-ring instead
I made this to drill my depth hole.
I like that idea a lot. Handle and depth stop all in one. Must be much faster than using the jacobs in the tailstock like I do now...
Considering Jacobs chucks...
Have you heard of or used taper shank bits? They fit directly into the morse taper of the tailstock (or the headstock)
Since I discovered them they are my first choice for drilling with the tailstock.
One reason is I don't need the jacobs chuck.
Another is it avoids the unnecessary length and possible compromises to precision.
Also very quick to use and change sizes.
The down side is it's an additional cost, but might be worth it for sizes used a lot.
One other thing is the smaller sizes use a #1MT and need a inexpensive adapter.
This picture compares the total length when using a small diameter standard twist drill in a jacobs chuck vs a taper shank bit, this one with a 2MT adapter::
I like using them so much I found sources and got sizes from less than 1/8" up to 1".
I first saw these when Rudy Lopez used one to get a start on hollowing a goblet. He used a 1" bit and cut it off short and resharpened.
Some taper shank bits. I think I now have most sizes in 32" increments and some in 64ths.
A 1" bit at the top, an #1 to #2MT adapter in the middle, smaller bits at the bottom.
Another thing about drilling I can't stop myself from mentioning is starter holes, especially when drilling deep holes or those where precising is needed. I always drill a starting hole with a "Center bit" then switch to the standard bit. Center bits are short and stout so they can't flex.
A set of center bits is cheap - will start even a long bit precisely without getting off a little and risking some wobble which can make a bit get off further by following the grain in a spindle. My drilling has improved since using these.
JKJ
Last edited: