spalted maple 10 inch bowl

[Dennis McManaman]

I am working on a 10 inch spalted maple bowl 10 X 4.
I have tons of voids.

I have read about filling the voids with various things and that may be what I have to go with.
However, I am wondering about surface sanding to 600 and then applying CA for 3 or 4 coats and then polishing it with CA polish??


Any ideas, and or suggestions?
Am I way off course?

Thanks

 

[Mark Mandell]

That's going to be a whole lot of CA, Dennis. I know it's used on pends and such, by why do you go to that expense on a large piece? I suspect that with the amount of seasonal movement in that much wood that your CA surface will crack and fail over time.

Spalted wood will have differing densities and porosities. I suggest that you consider preping the piece with several light applications of dewaxed shellac mixed to a 1lb. cut and then using an oil finish.

Voids can be very interesting on display pieces but they're not great for holding soup. There are lots of options to fill them, from epoxy, with or without colors or inclusions, to low temp metals like tin.

Domestic hardwoods don't get much benefit from sanding beyond 220. Finer grits are required, however, to get a good finish film. This is, however, a matter of preference, as some turners insist on sanding raw woods on up to the 2000 range and most anything in between.

 

[Dennis McManaman]

Thank you

As a novice turner I suspected that my logic was a bit out there....
I will try the light coats of shellac after I finish the piece. I still have a little shaping and tool mark tear out removal to complete before I finish the outside and reverse chick for the interior.
This is not going to be a utility bowl, more of a practice "art" piece.

Thank you for your knowledge.

 

[Richard Coers]

Are you really talking about voids, or chip out? Voids are missing wood from a natural occurance in the wood, such as bark inclusions. Chipout is self explanitory. Your phrase, "tons of voids" leads me to believe you have chipout. What tool are you using? Have you done any shear scraping? Tried applying a sanding sealer or thin shellac and then shear scrape?

 

[Mark Mandell]

As a novice turner I suspected that my logic was a bit out there....
I will try the light coats of shellac after I finish the piece. I still have a little shaping and tool mark tear out removal to complete before I finish the outside and reverse chick for the interior.
This is not going to be a utility bowl, more of a practice "art" piece.

Thank you for your knowledge.

Dennis,

Thin CA has been used to stiffen up punky areas in a turning, but I prefer Dick's recommendation to use shellac instead. It's a softer resin and will lead into the finishing routine.

 

[Dennis McManaman]

these are naturally occurring small holes.

I do however have some tear out from my 3/8 bowl gouge I suspect not presented to the work at the proper angle.
I have not yet tried any sanding sealer as I felt it would be better to do all the turning and shaping prior to????

 

[Dennis McManaman]

Thank you

Dennis,

Thin CA has been used to stiffen up punky areas in a turning, but I prefer Dick's recommendation to use shellac instead. It's a softer resin and will lead into the finishing routine.

I will try that in several light coats.

 

[hockenbery]

these are naturally occurring small holes.

I do however have some tear out from my 3/8 bowl gouge I suspect not presented to the work at the proper angle.
I have not yet tried any sanding sealer as I felt it would be better to do all the turning and shaping prior to????

The thin shellac or thin lacquer works well for hardening puncky areas in spalted wood. The alcohol makes it dry quickly and thin lets it penetrate.
Advantage of the shellac is it is compatible with other finishes. A blond shellac won't change to color much. A lacquer wash won't change the color at all but sort of works best with a lacquer final finish.

I have used Ca on problem spots but I almost always see it as an imperfection/ blotch in the finish later.

Tear out is reduced by light bevel riding cuts with a sharp tool.

Often spritzing the blank with water from a plant mister is enough to yield a clean cut.
The water swells the fibers and the lock together

Have fun
Al

 

[Bill Boehme]

I have used CA as a finish on a number of things including a few large bowls. The ones that I have done are either hard maple or mesquite and not all woods may work as well. Here is what I do:
1. Sand to at least P1500. I often use use Micromesh and polish to 6000 or higher.
2. I use super thin CA and quickly soak the wood and wipe level with a paper towel. I do this outdoors and keep my face away from the wood. If it starts fuming, I leave the area for a while.
3. Next, I level the surface and then apply a few coats of medium CA. It does not fume as badly as the thin stuff, but I still exercise caution.
4. Finally there is the really hard work of sanding level without creating waves or other telltale signs of hand sanding -- this is especially problematic when working with something that has "negative" space. High gloss finishes accent less-than-perfect work like a sore thumb, so bear that in mind.

I have tons of voids.

I think voids are weightless until filled. ;^)

 

[Bill Boehme]

Also, deep soaking with super thin CA is critical to long term stability. Otherwise, cracking is a likely long term possibility because of the brittle hardness of the plastic finish. I suggest turning the wood thin if you want to try this type of finish.

I buy Starbond by the pint. The cost of using tiny bottles would be pretty steep.

 

[MichaelMouse]

I still have a little shaping and tool mark tear out removal to complete before I finish the outside and reverse chick for the interior.
This is not going to be a utility bowl, more of a practice "art" piece.

Since nobody else mentioned it, I will. White areas where the wood has succumbed to lignin-eating fungus will have more of a tendency to peck out when the wood is wet. Drying and turning again will allow a properly presented edge to cut cleanly. "Riding" the bevel is about the worst thing you can do with delignified wood. You'll find yourself with proud sound areas surrounding the lower soft white. Same thing happens if you press while sanding.

You want to get a tool presentation that takes a shaving rather than chips and dust, just as always, but take it easy and keep the heel of the tool from heating, denting, and hardening in the white areas. I don't scrape, but if you do, keep the scraper in a shear and remove fuzz deep.

When sanding, either sand supported, as I do, so the paper can't follow and hollow, or sand from the sound into the unsound wood, going round and round until you're at the 320 level.

This birch shows semisound wood and delignified white. http://i35.photobucket.com/albums/d160/GoodOnesGone/CantSellBirch-1.jpg

A favorable angle to produce shavings.
http://i35.photobucket.com/albums/d160/GoodOnesGone/Forged-in-Use.jpg

 

[hockenbery]

. "Riding" the bevel is about the worst thing you can do with delignified wood. You'll find yourself with proud sound areas surrounding the lower soft white. Same thing happens if you press while sanding.

You want to get a tool presentation that takes a shaving rather than chips and dust, just as always, but take it easy and keep the heel of the tool from heating, denting, and hardening in the white areas. I don't scrape, but if you do, keep the scraper in a shear and remove fuzz deep.

"riding the bevel". Means different things to different people. The bevel is the surface of the gouge that was against the wheel in sharpening.
Most woodturners use "riding the bevel" to mean floating the bevel over the area just cut. On a convex surface the only a tiny bit of the bevel just below the cutting edge rides on the wood. In a bevel riding cut on a convex surface it is impossible to have the heel contact the wood.

A bevel riding push cut or pull cut produces only shavings.

When hollowing a bowl you can as MM mentions have too much bevel which can let the gouge touch at the heel and the cutting edge. Still the concept is to float the bevel of the gouge over the wood. One solution to decrease the bevel,drag an allow the gouge to operate smoothly in tight radius is to shorten the bevel. This can be done by either grinding a micro bevel or by grinding the heel of the bevel. An advanced shear cut with side ground gouge Has a minimal bevel contact and cuts a tighter radius that the push cut with the same tool.

Another solution is a concave bevel like Michelson uses has minimal bevel contact which is why it so good for thin turning.

Finally as MM implied the finish cuts need to remove successively smaller shavings.
When I'm hollowing with the side ground gouge, I'm taking 1/2" or wider shavings with a bevel riding push cut.
As I get close to my final surface, I take a passes removing 1/8, 1/16 and 1/32

"riding the bevel" means no pressure on the wood from the bevel. In hollowing the tool is swung through an arc with no pressure on the wood.


Have fun

 

[MichaelMouse]

Unfortunately, shortening the bevel puts you at a higher pitch angle for the same clearance angle, when you'd like to have a lower. Means pushing and bending/breaking the shaving rather than lifting and peeling it. You can gain a bit of what you lose back by skewing the tool, but unless you're using a broad sweep gouge, the sweet spot will be relatively short. VERY short if you try to do with some of the cylindrical gouges with the fat heels. Last two passes with a fresh edge and concede the sweet spot if you must. Else you have to drop the handle on the gouge to cut on the wing. Best if you have a constant sharpness angle grind on the wing for those cuts .

If the pitch angle gets too high, you'll find yourself pecking out those soft areas more, and if you lower your pitch, you can lose the clearance angle and get that heel rubbing again. One will leave rough pits, the other crushed fiber rings. Both a bear to sand out.

Review of edge terminology. http://homepages.sover.net/~nichael/nlc-wood/chapters/caop.html

 

[hockenbery]

Unfortunately, shortening the bevel puts you at a higher pitch angle for the same clearance angle, when you'd like to have a lower. Means pushing and bending/breaking the shaving rather than lifting and peeling it. You can gain a bit of what you lose back by skewing the tool, but unless you're using a broad sweep gouge, the sweet spot will be relatively short. VERY short if you try to do with some of the cylindrical gouges with the fat heels. Last two passes with a fresh edge and concede the sweet spot if you must. Else you have to drop the handle on the gouge to cut on the wing. Best if you have a constant sharpness angle grind on the wing....

If the pitch angle gets too high, you'll find yourself pecking out those soft areas more, and if you lower your pitch, you can lose the clearance angle and get that heel rubbing again. One will leave rough pits, the other crushed fiber rings. Both a bear to sand out.

Review of edge terminology. http://homepages.sover.net/~nichael/nlc-wood/chapters/caop.html

No no no
Lifting fibers is all wrong that cause tear out!

The bevel angle is exactly the same for grinding off the heel. The secondary bevel is always a bit steeper which works better inside a bowl.
With the push cut the sweet spot is cut on riding the bevel from rim to bottom center. The tool an be allowed to arc up and then back to center.

The shearing cut with gouge is made with the handle nearly level and the flute straight up. The cut is made on the leading shoulder of the tool.
It is a slicing cut and does a very clean surface.

MM, You seem to know a lot about a great many things..
However, your knowledge of the side ground bowl gouge is limited and often wrong.
You would do well to take class or attend some demonstrations to see how it is used properly.
It might totally change the way you turn wood.

Al

 

[Doug Reesor]

I am working on a 10 inch spalted maple bowl 10 X 4.
I have tons of voids.

I have read about filling the voids with various things and that may be what I have to go with.
However, I am wondering about surface sanding to 600 and then applying CA for 3 or 4 coats and then polishing it with CA polish??


Any ideas, and or suggestions?
Am I way off course?

Thanks

Dennis,

An artist friend of mine commented on the willingness not to fill the voids was what made it beautiful. I often try to clean out the natural voids and then polish lightly. As an alternative, I mix powdered copper with CA glue as a filler. It really looks cool and the color goes with maple.

Doug

 

[Bill Boehme]

Al, I am not positive, but I think that MM isn't saying what you assumed. I suspect that the issue might be misinterpretation because of his style of expression that is sometimes a bit different from the typical woodturner phraseology. That may sometimes lead to misinterpretation and other times it leads to an "aha moment".

It is just my 2¢ and I might be all wet.

 

[hockenbery]

Al, I am not positive, but I think that MM isn't saying what you assumed. I suspect that the issue might be misinterpretation because of his style of expression that is sometimes a bit different from the typical woodturner phraseology. That may sometimes lead to misinterpretation and other times it leads to an "aha moment".

It is just my 2¢ and I might be all wet.

There is a communication gap for sure!

 

[Bill Boehme]

There is a communication gap for sure!

OK, step one accomplished -- recognition.

 

[MichaelMouse]

How about you want to "slide under" it instead of "lift?" Would that satisfy you? Sliding and slicing rather than pushing and tearing, which is the result when your pitch angle gets too high. I gave you pictures, right?

To set your mind at ease, I have used the side grind since the pattern was first presented early 70's as a way to avoid the heavy heel on cylindrical stock gouges which replaced the forged. I use it all the time to dig wood, even "ride" the bevel when doing so. Communication problem there, which can be easily remedied by using "guide" to differentiate between a basic carving dig which does contact the heel while the leading edge is engaged and a planing move which wants a clearance angle.

I've seen a lot of people trying to use a lot of grinds to make their final cuts. I've tried a lot myself, which is why I use broad sweep, shearing the cutting face and skewing to make an already low angle seem lower. Another communication conundrum regarding the terms shear and skew. I take skew in the standard definition of angling to the direction of tool travel, while the term "shear" is the angling of the tool across that direction. Shear in my lexicon is done by the piece, while skew is done by my hand. The "shear scrapers" seem to refer to what I call skew as shear. Once again, I favor the standard edge terminology presented in the article referenced. The plane fanatics take it further, defining the "type" of shaving produced by the various angles.

The biggest communication problem, however, is the predisposition to dispute rather than understand. Thank you for your opinion that I need to study with your mentors so I can do it your way, but I was merely describing mine. Pictures and text, even.

 

[hockenbery]

How about you want to "slide under" it instead of "lift?" Would that satisfy you? Sliding and slicing rather than pushing and tearing, which is the result when your pitch angle gets too high. I gave you pictures, right?

.

I try never to get under the fiber either by sliding. I try to cut across the fibers with a supporting fiber behind it for a clean surface.

Getting under the fibers always produces tearout and a poor quality surface.

Al

 

[Bill Boehme]

Being a nonconformist is he11. MM, It looks like you will have to use the "right" terminology or else.

Like I previously said, I might be all wet, but it appears to me that you two are saying basically the same thing, but with different ways of expressing it.

While you and I are not always on the same page, I do appreciate your perspective. I try to avoid seeing things as being purely black and white.

One of the things that I appreciate about this forum is that folks state their viewpoints (sometimes emphatically) without getting personal.

I am starting to discard some of my "rules" that discourage more than encourage those who are just learning. A bowl CAN be scraped or even sanded with a 60 grit gouge. Bowls CAN have a flat bottom with ripples and a vertical side. Crisp corners are not mandatory. Once we're on fire with the turning bug, we can then learn about growing -- and provide income for the pros.

 

[hockenbery]

I am starting to discard some of my "rules" that discourage more than encourage those who are just learning. A bowl CAN be scraped or even sanded with a 60 grit gouge. Bowls CAN have a flat bottom with ripples and a vertical side. Crisp corners are not mandatory. Once we're on fire with the turning bug, we can then learn about growing -- and provide income for the pros.

Bill,
Anything that gets people into turning is a good thing. I think we all try to have an understanding that when someone brings a piece to show us it is often the best piece they have done to date.
I also think this forum has a lot of novice turners and the more experience have an obligation to give them fundamental advice that is
Safe, Effective, and does not confuse them unnecessarily.

Most turners go through a phase of turning bowls with flat bottoms and straight walls because our gouges cut straight lines following the bevel.
These are the hardest bowls to turn well and the hardest to dry from green wood and a one theme I cover in a working with greenwood demo.

A lot of nice bowls are roughed out with chainsaws. Others are cut on bandsaws. When you see them on the table we may not be able to tell they did no come from the lathe. Some tools do some jobs better than others. But in the end any tool that satisfies the turner using it is fine.
Al

 

[MichaelMouse]

I try never to get under the fiber either by sliding. I try to cut across the fibers with a supporting fiber behind it for a clean surface.

Getting under the fibers always produces tearout and a poor quality surface.

Here's a little experiment for you. Requires a pocketknife, substitute for a gouge, and a piece of wood long enough to hold with a full hand and still have six-eight inches beyond. Lay the blade on the wood with nearly no clearance angle ("riding" the bevel), and you'll find you really can't get much going at all. Lift to get a 20-30 clearance angle and you'll get to a point where you can cut pretty cleanly across the fibers. Don't dig in too far, maintain that high angle, and try to get a smooth cut. Can't do it, because you're compressing and pushing, trying to get things out of the way. Now start the same cross entry and immediately lower the clearance angle to maybe 5-10, and you'll find you can stay under the wood and get a pretty smooth surface after the edge passes. With a bit of think, you'll realize that this is why I like to arc the tool into the surface to start and almost immediately get under to start a shaving.

Now do the same, only skew the edge to the direction of the cut as you begin to push. Meeting a lot less resistance, right? Makes the wood think it's being planed at an even lower angle than it actually is. Now you're shaving and skewing, so let's try a shear.

Make your rotating entry cut fairly close to the near end of the blade, skew, and draw the blade across the stick as you progress. You have to do the draw here, rather than let the rotation draw it down the edge as on the lathe. Now you're shaving, skewing, and shearing simultaneously. Experiment with different degrees of skew and shear, and you'll find that the basic 2-dimensional cut doesn't get much benefit from shear, compared to lower angle and skew. When you have a curved surface like the gouge, engaging a curved surface like the inside of a bowl, the shape makes a fine shear, where any point higher on the gouge than the point of original contact can be sheared to deepen the initial cut. Why I like the noses ground in an arc of a circle, something that produces a narrow sweet spot with a "bowl" grind.

Scraping is also a possibility, if you're not using broad sweep gouges. You have to get at an angle of 90 degrees or better to scrape straight ahead, and when you try, you'll feel the fuzz where things compressed and broke rather than sliced. Go past 90 and you'll be "negative" scraping, and get a better surface. Skew will help, but shear will deepen the cut, the recipe for disaster for ham-handed scrapers.

 

[hockenbery]

mm,

The planning analogy does not work very well for woodturning beyond turning a cylinder.
The wood plane wants to tear the fibers because it is cutting into the end grain and wants to split the wood rather than cut it.
So all those thing you describe are to overcome the splitting and make the tool cut.
When you joint wood the plane needs to feed against the face grain arrows for a clean cut so that it cuts downhill.

Take your knife and cut a cove. Take it to the end of the stick and round the end into a bowl shape.
In these you cut across the fiber and get a clean cut.

Notice when you cut the cove you have to start from the top and cut down across the fibers from each side.
If you try to cut up the cove it tears the fibers.

This is a great way to show beginners how the tools work. The gouge is like a curved knife blade

Bowl turning cuts are more like cross cuts that ripping cuts.

The sharpening angle definitely affects the quality of the cut.
A 30 degree sharper and cuts cleaner than 55 degree which is sharper than an 80 degree.


Al

 

[MichaelMouse]

mm,

The planning analogy does not work very well for woodturning beyond turning a cylinder.

It works just fine, Al. You just have to do it.

http://s108.photobucket.com/user/MichaelMouse/media/CherryPeelIn.mp4.html

Outside doesn't need much swing, because the wood rises.

http://s108.photobucket.com/user/MichaelMouse/media/35mmGougeRounding.mp4.html

The sharpness angle does affect the way you may cut. There's a thread growing in techniques about using tools with large sharpness angles - scrapers, they call them. Of course, the quality of the cut does not depend on the sharpness angle, rather the quality and presentation of the edge. Notice that the Hunter tools work best when they slice like the hook/ring tool from which they derive, taking advantage of the constant angle grind. Their cutting edge is like the classic cabinet scraper with its turned edge, excellent for low angle planing. Those with curved cabinet scrapers, especially if they own a dial-an-angle burnisher like the LV tool, will find it's an excellent tool for scraping into a bowl. You must remember to go downgrain, of course, but that just means four quadrants if you go round. The angle of the turned edge will determine if it planes or pushes within a particular curve.

 

[hockenbery]

Mm,
Nice examples of the bevel riding push cut.

How did the cove go with the pocket knife.

Al