torn end grain

**1scott** · 02-22-2004, 11:10 PM

besides sharp tools, and sanding...how can you deal with this??? i cut my finger on my bowl gouge so i figure it is sharp...i power sanded from 80 grit up through 320..i cant seem to get rid of this. ANY suggestions???? i know there must be a way.
thanks

**TDHofstetter** · 02-23-2004, 12:50 AM

Beggar, I know it is. Hand sanding with the power OFF, sanding downhill, towards the end grain. If your lathe can be reversed, that's a big plus... then you can run the piece for'ards and back'ards while you sand.

-- Tim --

Don't walk in front of me, I will not follow.
Don't walk behind me, I will not lead.
Walk beside me, and be my friend.

**WoodMangler** · 02-23-2004, 09:00 AM

I'm sure I will sound like a broken record here... and I apologize...

I use CA to stabilize the area so that, instead of bending and tearing, the fibers get cut... I use the gentlest cut I can... I mean, I try to have just the finest "angel hair" shavings for my final cut, and I will use a cutting tool instead of a scraping tool when I have areas that are being a PITA...

.... and now I have a witness!... Everett?... where are ya man? :)

Bill G · 02-23-2004, 09:16 AM

There are a few ways to handle torn end grain, which is the bane of all turners. Some work, some don't, and in some cases it is almost impossible to fix. Heavy sanding will sometimes work, but you have a lot of material to remove.

The sharpness of the tool is not as important as the presentation of that tool. Of course it needs to be sharp, but different presentations cut the wood differently with the same edge of the same tool. For example, if you refer to my long post on rough bowl turning, the main cut I am using is what I call my 45, 45, 45 cut. This is an aggressive cut that removes a lot of material quickly. However, it can also leave a lot of tearout - in fact, it usually does, even on forgiving species.

There is a second cut I use frequently when it comes time to refine the shape and remove tearout on a bowl. I call it the tangent cut. I do not have a picture of it right now, but in essence, the bowl gouge is held in such a way that it is in a line tangent to the point of contact of the bowl. In other words, the long axis of the gouge is held so that the force of the spinning wood is directed along that long axis. The bevel of the gouge is rubbing along the side of the grind, not the tip, with the flute pointing in the direction of the cut. The flute is then rotated over slightly so that the long edge of the grind starts to slice through the wood fibers very cleanly. This cut will not remove a lot of wood quickly (well it will if you push too hard, but you don't want that), but it will remove about 95% -100% of tearout on the exterior of a bowl.

If you have tearout on the inside, there are a few things to observe. Is the bevel rubbing at all? That helps some? How fast are you cutting? That is, how fast is the lathe spinning? You don't want it ready to take off or anything, but if you are cutting at the low end of the speed range, you won't get as clean a cut. Have you tried a sharp scraper? A conventionally ground scraper will not give a very good cut, but if you grind the edge back to about 30 degrees, you will get wispy thin shavings and usually a smooth surface. Finally, there is the shear scrape with the gouge inside the bowl. This is an advanced cut, and can go bad very quickly if you lose your concentration and focus on what you are doing.

To shear scrape with a gouge inside the bowl, the gouge must be sharp to get good results. It also must be flat, or parallel to the ways of the lathe, and both edges must start out touching the wood. In other words, it is "upside down" in its presentation. It must be on center. Failure to observe ALLof these conditions will result in some spectaular, pants wetting catches. To make the cut, position the tool as described above, and then rotate the top edge away from the surface of the wood just far enough to get some air between it and the surface of the bowl. The farther you rotate it, the more likely the gouge will catch. Then draw the tool along the surface of the bowl lightly from center to edge. You can go from edge to center, but that is pushing it (ha ha). Seriously, that does not work as well, and is more difficult to control in most cases.

As a final fix, whan none of this other stuff works, wet sand the bowl with a drying oil (Danish Oil, Tung oil, whatever) as a lubricant. The slurry of oil and dust will fill your tearout and make it less visible. Once the oil dries, it will be held in fairly well.

Good luck with it. I hope this helps.

Bill

**1scott** · 02-23-2004, 11:13 AM

i did try the reverse spin thing..i have a shopsmith too and i mounted it and tried that...i have another piece that i will give a real try with the CA...when i did attempt it with this one, the glue seemed to just spread and absorb into the wood...anyway, i will try again...just frustrates me when i see everybody (seemingly) get perfect glasslike results and i dont....

**WoodMangler** · 02-23-2004, 11:25 AM

I think I hurt my widdle bwain on this...

"There is a second cut I use frequently when it comes time to refine the shape and remove tearout on a bowl. I call it the tangent cut. I do not have a picture of it right now, but in essence, the bowl gouge is held in such a way that it is in a line tangent to the point of contact of the bowl. [font color ="green"](Lost me here)[/font] In other words, the long axis of the gouge is held so that the force of the spinning wood is directed along that long axis. The bevel of the gouge is rubbing along the side of the grind, not the tip, with the flute pointing in the direction of the cut. The flute is then rotated over slightly so that the long edge of the grind starts to slice through the wood fibers very cleanly. This cut will not remove a lot of wood quickly (well it will if you push too hard, but you don't want that), but it will remove about 95% -100% of tearout on the exterior of a bowl."

Main Entry: 1tan·gent
Function: adjective
Etymology: Latin tangent-, tangens, present participle of tangere to touch; perhaps akin to Old English thaccian to touch gently, stroke
1 a : meeting a curve or surface in a single point if a sufficiently small interval is considered <straight line tangent to a curve> b (1) : having a common tangent line at a point <tangent curves> (2) : having a common tangent plane at a point <tangent surfaces>

*sigh*... that didn't help either... That's what I get for dropping outta school to join the Army eh....

Any help would be greatly appreciated... and I'm sure a pic will fix me right up!... Heck, I may be already doing this!

Bill G · 02-23-2004, 03:52 PM

Hi Mark

I'll work on a picture for you in the next day or so. I am supposed to up doing a production job on spindles right now, and I need to get it done before I get in trouble with several people. ;)

Bill

**TDHofstetter** · 02-24-2004, 01:36 AM

Yeah, I think the thought there is to make more a slicing cut than a chopping cut, kinda'... like skewing a handplane 'way over to an angle so it slices diagonally instead of dead-on.

In effect, it makes the angle of the tool much more acute - effectively making the tool a very thin-edged tool that can slice more like a razor than like a cleaver.

-- Tim --

Don't walk in front of me, I will not follow.
Don't walk behind me, I will not lead.
Walk beside me, and be my friend.

**Sawduster** · 06-02-2010, 09:14 AM

I think he is talking about holding the gouge at an acute angle to the workpiece/axis when viewed from above and riding the side bevel as opposed to the bottom bevel, presuming a fingernail grind.

Picture might help.