Hollowing direction?

[Gabe Latner]

I've been told (and read) that when hollowing endgrain, you have to cut from the center towards the rim (i.e. the opposite of a normal bowl) to avoid catches and 'skipping'.

Every time I try this, I get horrible catches/skipping, but hollowing from the rim towards the center seems to work fine.

I know it's hard to tell without seeing me do it, but does anyone have thoughts on what I might be doing wrong?

 

[Richard Coers]

What diameter are you trying to hollow? If your tool is pretty big and the vessel is small, you are probably not getting any support from the bevel. Another problem can be the rotation angle of the flute

 

[hockenbery]

What tool are you using and how are you presenting it.

Here is a clip from a demo shows how I hollow a small bowl for a scoop.
In this I drill and then cut toward the left outside to show that method but my hand covers the cut
Then I do a back hollow - this is worth learning if you do goblets or boxes. In the back hollow the cut is toward the outside wall.

Spindle Gouge - Drilling & Hollowing -

View: https://www.youtube.com/watch?v=dOEsrpLyDV4

 

[Lyle Jamieson]

I've been told (and read) that when hollowing endgrain, you have to cut from the center towards the rim (i.e. the opposite of a normal bowl) to avoid catches and 'skipping'.

Every time I try this, I get horrible catches/skipping, but hollowing from the rim towards the center seems to work fine.

I know it's hard to tell without seeing me do it, but does anyone have thoughts on what I might be doing wrong?

What boring bar are you using, and what cutter?? Are you scraping or slicing with bevel support??

 

[Randy Heinemann]

If you are using a hollowing tool ( not a gouge) it most likely won’t matter which direction. A bigger problem for me when I first starting hollowing was that I tended to move the tool past the center. The result is quite a sudden and aggressive lurch of the hollowing tool. Once I stopped that I was able to remove material in both directions.

 

[Gabe Latner]

I was using my bowl gouges (1/2 and 5/8), with the flute pretty much all the way "closed" with bevel support. I've been working on larger pieces (end grain bowls) at least 5" in diameter.

@Hockenberry, thank you for the video!

 

[robo hippy]

Richard Raffen recently released a bunch of videos on You Tube. He does comment on this cut. The most important thing when doing this cut is to avoid having the nose of the gouge contact the wood. It is the wing, not the nose that is doing the cutting, and if the nose contacts, you get a very nasty catch. I am learning this cut, and wish I could have a hands on session with some one who knows the cut. I leave the gouge on the tool rest at the 9 o'clock position rather than the noon position. Makes it easier to control for me.

robo hippy

 

[Tom Gall]

I was using my bowl gouges (1/2 and 5/8), with the flute pretty much all the way "closed" with bevel support. I've been working on larger pieces (end grain bowls) at least 5" in diameter.

@Hockenberry, thank you for the video!

I use this 'wrong way' cut all the time in endgrain - especially in hard, tight grained wood. I find it to be pretty efficient and a very clean cut. I use a closed flute to start the cut but then gradually open it up (just like in a side grain bowl). The start of the cut and the end of the cut (center) are where a catch or run might happen. The bevel must always rub when going against the grain. Depending on the shape (tall or with an undercut rim) I will finish with a hook tool, ring tool (Termite), or scraper held at about 45º.

 

[Lyle Jamieson]

I've been told (and read) that when hollowing endgrain, you have to cut from the center towards the rim (i.e. the opposite of a normal bowl) to avoid catches and 'skipping'.

Every time I try this, I get horrible catches/skipping, but hollowing from the rim towards the center seems to work fine.

I know it's hard to tell without seeing me do it, but does anyone have thoughts on what I might be doing wrong?

Hi Gabe! Thanks for posting you question on the AAW Forums. You’ve gotten some great feedback and advice. It is a great place to ask questions like this. I would also encourage you to get involved in your local woodturning club and seek out someone that might be able to help you in person.

Bear with me, as I try to cover a few more pieces to the puzzle.

First, in trying to answer your question, grain orientation is a great place to start. Many turners don’t pay enough attention to this topic. So, congratulations……that is great that you recognize the importance!

Cutting into supported fibers is easier on your body, your lathe, the wood etc. – results in less time sanding.
Most importantly it reduces the chance of a catch.

Most of the time in a bowl format we are in a side grain situation – the grain is perpendicular to the bed of the lathe. So, if you are turning a hollow form, you are correct in your statement we should be cutting out from the center when hollowing a vessel, in an end grain format – the grain is horizontal to the bed of the lathe.

The problem you are having, in my opinion, is that you are trying to use a tool that does not fit the application. When making any cut we either have to have bevel support or we have to understand the 90 degree rule. (The angle of the cutting surface, as presented to the wood, HAS to be 90 degrees or less). A “bowl” gouge, which I use for 99% of the work I do (Push, Pull, Scrape, and Sheer Scraping), the grind is designed for, just that, a bowl. It is possible to hollow a vessel with a bowl or spindle gouge, but you are limited in the shape you can design because you cannot maintain bevel support. This will lead very quickly to getting a catch.

If you are just making a cylinder with straight sides, like in the video that was shared, you can do some hollowing with this cut. BUT, it is a very difficult cut, that can take a long time to master. Especially if you have some shape to your vessel and start exceeding the limitation of your tool in depth.

I would encourage you to put down the bowl gouge, or spindle gouge, when you get to the hollowing portion of your project. I would recommend a boring bar for hollowing, preferably a captured hollowing system.

“Catches” and “Skipping” are 2 words that shouldn’t be in our vocabulary as woodturners. They are scary, dangerous, and NOT fun! A captured hollowing systems can eliminate the possibility of catches when hollowing.

If you have any questions, don’t hesitate to contact me directly thru my website contact form, or email me directly at lyle@lylejamieson.com.

Hope this helps!

Regards,

Lyle

 

[Dave Landers]

I would encourage you to put down the bowl gouge, or spindle gouge, when you get to the hollowing portion of your project. I would recommend a boring bar for hollowing, preferably a captured hollowing system.

Personally, I think a captured hollowing system is way overkill for the 5" end grain bowls that @Gabe Latner says he's turning.

Gabe - Cutting into end grain can be challenging in lots of ways, but a bowl gouge can work just fine on an open form (where the rim is the widest thing (or close to the widest) on the bowl). A closed form (where the opening is noticeably smaller than the diameter) is another story (and there's a big grey area between what's open and what's closed).

Anyway - cutting from the center-out on the inside of a bowl with any depth to it (like, it's not a plate) is pretty much impossible with a gouge, as there's no way to keep the bevel in contact with the wood (when the bevel rides on the wood, the handle is going to need to extend thru the wall of the bowl).

Scrapers tend to work well against end grain. Whether a scraper will work better in your situation vs a gouge cutting "the wrong way" depends on the form (shape) you are making and a bit on the wood itself. If you want to try a scraper, I'd suggest either carbide tools or a negative-rake (flat-top scrapers tend to be grabby/catchy inside a bowl). Otherwise, I say to heck with the "rules" - if cutting "the wrong way" is producing good results for you, fine.

 

[hughie]

As I use hollowing tools almost exclusively, so some of these common issues aren't always there for me. But I do complicate it by with blank orientation, by that I mean the desired end result will dictate orientation and at times it will throw up a challenge. But using shielded hollowers such as the Woodcut Pro Forme or Rolly Munro's Wunderkut largely gets me out of trouble most days of the week

 

[Neil S]

As I use hollowing tools almost exclusively, so some of these common issues aren't always there for me. But I do complicate it by with blank orientation, by that I mean the desired end result will dictate orientation and at times it will throw up a challenge. But using shielded hollowers such as the Woodcut Pro Forme or Rolly Munro's Wunderkut largely gets me out of trouble most days of the week

I don't do anywhere near as much hollowing as Hughie, but when I do I also use the Woodcut Pro Forme, and occasionally the Rolly Munro's Wunderkut, as I prefer a cutting tool to a scraper for most of the hollowing out. For the finishing scraping cuts I prefer the Woodfast scraper tip added to the Pro-Forme bars. That tip is the only one I know of that can be "positioned at an angle" for inside shear scraping...

Woodcut Tools Pro-Forme Scraper kit - Hollowing Tools

www.cwsonline.com.au

To cut downhill (or if you prefer 'with supported fibers') I keep the following images in mind whenever I'm hollowing, which is the opposite direction of how we cut on the outside of pieces...



If I'm hollowing pieces with a wider opening, sometimes I won't bother using a dedicated hollower and will just use a bowl gouge in scraping mode. A woodcut bowl gouge with a Ellsworth style grind works quite well for that. Scraping is less fussy about the direction and the solid shaft on the Woodcut bowl gouges allow for an extended reach off the tool rest with less vibration....

View: https://www.youtube.com/watch?v=Bi06BX4vnOI

 

[Gabe Latner]

Thank you all for your advice. I may have made a terminology mistake. I'm not "hollowing" a vase/hollowform/pot where the opening is smaller than the interior cavity. I've been turning wide mouthed bowls/saucers that just happen to have the grain running parallel to the bed of the lathe. Based on all the comments, it sounds like the "center out" approach isn't necessary/doesn't apply.

 

[hockenbery]

center out" approach isn't necessary/doesn't apply.

Yes and no.

To cut fibers cleanly you would cut from the bottom center to the rim.
This doesn’t work because you would be cutting a thin walled rim last and wood movement makes this not work.
With a sharp tool and light cuts you can cut against the grain with minimal tear out that can be sanded out.
Often the tear out will be hard to see.

If you plan to do a lot of these endgrain bowls there are tools to consider that will save you sanding.
Ring tools, covered ring tools, hook tools, Hunter carbides.
Someone mentioned the Rolly Munro tool this is a covered ring tool.

 

[Neil S]

Yes and no.

To cut fibers cleanly you would cut from the bottom center to the rim.
This doesn’t work because you would be cutting a thin walled rim last and wood movement makes this not work.
With a sharp tool and light cuts you can cut against the grain with minimal tear out that can be sanded out.
Often the tear out will be hard to see.

Or, use a scraping cut with a bowl gouge from the bottom centre out and upwards. The grind needs to be right for that if you are cutting inside an endgrain bowl. See my brief 24sec video in above post to see a suitable grind for this. 40/40 and 45° grinds are not suitable. An Ellsworth 65° grind is good and 55° might be OK.

The video shows me cutting under the shoulder of a crossgrain piece, but you use the same closed orientation of the flute to the wood in an endgrain bowl. Starting in the centre with the tip of the flute doing the cutting/scraping and as you 'pull' out and up the inside of the piece the bottom wing will be doing the work. The direction of the cut is less critical for that cut/scrape.

The wings on an Ellsworth grind are quite acute and the scraping cut is quite severe on them, so I find that the bowl gouge edge, and particularly the wings, needs to be refreshed more frequently than when used for push cuts.

Give it a try and see how you go and if you don't like it then go back to what was working for you before.

Years ago I used to turn endgrain pieces out of small limbs. They were quick to make, so I didn't need to put much of a price on them, and they sold well at the gallery. By turning some in endgrain orientation I was able to leave a ring of bark on them, which appealed to some buyers...

​

I've also turned quite a few tall hollow form endgrain pieces, but never endgrain bowls. I'm curious to know why you are turning bowls with the grain in that orientation, Gabe?

 

[Gabe Latner]

@Neil S , I had some limb pieces that someone had cut into cookies 2-3" deep. Thought I'd try something different.

 

[Neil S]

@Neil S , I had some limb pieces that someone had cut into cookies 2-3" deep. Thought I'd try something different.

OK, I understand now why you are working with the grain in that orientation. Definitely try the reverse scraping cut with a bowl gouge inside those to see if that works for you. If you don't already have a BG with an Ellsworth style of grind on it you will need to do that for that cut.

 

[Lyle Jamieson]

Gabe, doing end grain bowls goes against conventional thinking. The grain will be weak on the rim of a bowl and could break off like a potato chip if turned thin. Side grain is stronger and can be turned thinner safely. But in my thinking, even more important, is the possibility of cracking with the pith in it. I never turn with the pith in any of my work. Turn the branch piece on its side and you can get almost as big of a bowl as doing it end grain.

Thanks again for addressing this topic. Great perspectives from many. And thanks to Neil for the drawing of the INSIDE hollow forms and bowls to use the advantage of moving the tools in the correct direction. It is confusing because the grain is different outside, different inside, different in the bottom, different on the top. There are significant advantages to cutting with supported grain. Most folks don’t take grain orientation seriously. The most important thing is preventing torn out grain, this is next to impossible to sand out. Using sharpest tools will help as some have already pointed out. Going downhill or the direction of supported verses unsupported fibers is just easier, safer, and the surface left behind is much better. This works with scraping or bevel supported slicing cuts. The grain orientation is critical to me. I N-E-V-E-R go the wrong way. No need, and why not do it the easy way. The only place it would not be necessary to use supported grain is on a flat board with grain parallel to the surface, like the bottom of a platter, but out at the rim it will be beneficial to go the right way. (I seldom use these terms, right, wrong, good, or bad, there is a lot of ways to skin the cat, but with the grain issue there is a correct and an incorrect way.)

Now to define the confusing part. The grain direction of the cuts will not, in and of itself, cause a catch or grabbiness or skipping. Catches and grain are two different subjects, and we tend to lump them together in our thinking. Your opening of this thread was about your frustration on how to prevent catches. It’s simple to explain but not that simple to do without some practice or hands-on help. There are two categories of cuts; scraping and slicing. I prefer to use a bevel supported slicing cut. The advantages are because I am basically lazy and it is easier on my body, easier on the wood, easier on the lathe, and it’s a lot more fun. I can turn faster, bigger, taller, safer with a slicing cut. Many famous turners use scrapers, they work fine, but have some limits that I do not want to live with. Many use scrapers to remove tool marks from bowl gouge use and that will work if the tool marks are really bad. Small subtle tool marks can be sanded out easily. The result of scraping will make torn out grain that will be very difficult to sand away.

When you scrape you must present the sharp edge of your tools against the wood at less than 90 degrees. You can scrape with either a dedicated scraper or any other sharp edge, like a bowl or spindle gouge. Anything over 90 will get a catch, period. So if you scrape at less than 90 degrees or always have bevel support when slicing you will never get a catch.

If I understand your dilemma, you are using a scraping cut with a bowl gouge. I do this often . . .but not inside a bowl. If you are getting a catch, you do not have bevel support and/or have violated the 90-degree rule of scraping. Coming from the center out is necessary when turning end grain to cut supported fibers. With a bowl gouge most grinds would make it almost impossible. It is often difficult to know when your cut is hidden inside a vessel or bowl when you are breaking the rules, but the catch will tell you in a hurry. How to fix it?? Rolling/twisting the gouge counterclockwise with a swept back wing gouge might work, pointing the flute toward the vessel wall. It can be as simple as raising the tool rest to insure you are scraping above the centerline. This might be difficult again when cutting near the center of the bowl because the handle will hit the rim. Again, get some help from an experienced scraper to learn how to use a bowl gouge to scrape.

Someone said we don’t have to follow the rules. That is true!! You don’t even need a lathe to get something round. But there is a cost, and there are limits imposed on you when you do not take advantage of the methods that are the most efficient.

To complicate this there are many different needs in turning. I turn wet wood, some turn dry wood. I choose to turn without vibration, others accept it, Some use chucks, I don’t use chucks, some turn finials, I rarely do, some do bowls I usually turn Hollow forms, some embellish . . . I like the simple elegance of natural wood. Again, not right or wrong, different for different purposes, all good. A technique that works for one thing might not work for other turnings.

 

[Neil S]

If I understand your dilemma, you are using a scraping cut with a bowl gouge. I do this often . . .but not inside a bowl. If you are getting a catch, you do not have bevel support and/or have violated the 90-degree rule of scraping. Coming from the center out is necessary when turning end grain to cut supported fibers. With a bowl gouge most grinds would make it almost impossible. It is often difficult to know when your cut is hidden inside a vessel or bowl when you are breaking the rules, but the catch will tell you in a hurry. How to fix it?? Rolling/twisting the gouge counterclockwise with a swept back wing gouge might work, pointing the flute toward the vessel wall. It can be as simple as raising the tool rest to insure you are scraping above the centerline. This might be difficult again when cutting near the center of the bowl because the handle will hit the rim. Again, get some help from an experienced scraper to learn how to use a bowl gouge to scrape.

Gabe

That is all very good stuff in that last post from Lyle.

Having raised the option of using a bowl gouge to hollow out endgrain pieces I thought I should add a short video to show what I meant. Not that I do this very often and I had to go and find a bit of limb to do it on. Like Lyle, I wouldn't normally consider an endgrain blank as suitable for an open form like a bowl for all the reasons that he points out.

Anyway, here I am using a bowl gouge with the Ellsworth grind...

View: https://youtu.be/-wCr4q5Pro0​

And here is the finish off the tool. As you can see, there are no residual toolmarks...

​

You could achieve the same cut with a 'flat' scraper, but that won't clear the shavings a readily as the bowl gouge. With a flat scraper the shavings pile up inside the piece and quickly obscure progress. As you can see in the video, the bowl gouge ejects the shavings.

I wouldn't use a roughing cut like that inside crossgrain work myself and not in that direction, but often use lighter scraping finishing cuts if the bowl gouge is still in my hand and the wood is suitable for that. In open forms like bowls the tip of a bowl gouge (with an Ellsworth grind) when presented with the flute closed to the wood can give more of a shear scrape.

BTW, I do almost all of my turning outboard nowadays, so handle position is not an issue for me with any of that.

 

[hockenbery]

Anyway, here I am using a bowl gouge with the Ellsworth grind...

Nicely done. Quite similar to Raffan back hollowing with spindle gouge
Sort of a down side up both are peeling cuts with the wing

Seems better suited for a wide vessel.

 

[Gabe Latner]

Thank you all.

@Neil S , is your video rotated? (I E. Are you moving the tip of the gouge "sideways" or "down"?)

 

[Dean Center]

I've made a few end grain bowls, and a lot of boxes, which involves end grain hollowing.

If you are end grain hollowing, drilling a depth hole to start the process gives you an easier task and more options for method. For example, you can do it with a bowl or spindle gouge in a closed orientation by starting in the drilled hole, flute outward, and sweeping it toward the outside. Or with the same tool orientation, starting in the hole and rotating it around a fulcrum made by your finger on the tool rest. These don't generally have the bevel on the wood, unless you have a very blunt grind on the gouge.

The best contemporary method is probably using a Hunter tool with a cutting carbide end in the same way one would use a hook tool, which allows a bevel rubbing cut. The bevel is just 'sideways' to allow it to maintain contact, and produce a smooth cut surface by cutting 'downhill'.

The Raffan 'back hollowing' method is less appropriate when you are making an open bowl, as it makes a pear shaped hollow with the skinny portion towards the tool rest--the opposite of the shape you want.

 

[hockenbery]

The Raffan 'back hollowing' method is less appropriate when you are making an open bowl, as it makes a pear shaped hollow with the skinny portion towards the tool rest--the opposite of the shape you want.

I would agree for a large bowl the back hollowing with a spindle gouge is not appropriate.

The back hollowing is good at hollowing wider than the opening. It is not limited to the narrower openings and can hollow a hemispherical bowl shape.
I wouldn’t use it for a bowl wider than 4-5” I use it for goblets & boxes


For vases with wide rims I would go to the termite, a hook tool, a covered ring tool, or a Hunter tool.

For vases an goblets with thin walls I do the opening first and then turn the outside. Less stress on the wood this way.

 

[Don Wattenhofer]

The back hollowing is good at hollowing wider than the opening. It is not limited to the narrower openings and can hollow a hemispherical bowl shape.
I wouldn’t use it for a bowl wider than 4-5” I use it for goblets & boxes

I have used the back cutting method for at least 25 years, but only for end grain work and never even considered doing it on side grain work.
The technique may work for side grain but I have never tried it, just does not seam like the right choice of techniques.
The shallow flute / spindle gouge / detail gouge works well similar to a spoon bit for starting a hole in the end grain piece and then you can immediately transition to back cutting.

 

[hockenbery]

I have used the back cutting method for at least 25 years, but only for end grain work and never even considered doing it on side grain work.
The technique may work for side grain but I have never tried it, just does not seam like the right choice of techniques.
The shallow flute / spindle gouge / detail gouge works well similar to a spoon bit for starting a hole in the end grain piece and then you can immediately transition to back cutting.

I agree completely - I wouldn’t use back hollowing on face grain.

This thread is about hollowing end grain.

How wide of an endgrain bowl have you done back hollowing?

 

[Neil S]

Thank you all.

@Neil S , is your video rotated? (I E. Are you moving the tip of the gouge "sideways" or "down"?)

That was done down so that my hand wasn't in the way of the camera, but you can do it either way. If doing it sideways you can use a squeezing action with your tool rest hand and a sideways swinging action with the other hand. The critical orientation is the almost closed flute facing towards the wood surface.

 

[Neil S]

Nicely done. Quite similar to Raffan back hollowing with spindle gouge
Sort of a down side up both are peeling cuts with the wing

Richard's back hollowing cut with the spindle gouge into end grain is definitely a bevel rubbing cut, not a scrape.

My little video shows a scraping cut. By definition, a scraping cut is done with the cutting surface of the tool at less than 90° to the wood. Scraping cuts with the bowl gouge done that way are easier to master for the novice turner.

Richard's back hollowing cut is fast and it does cut with the end grain, but It is not easy to master! For anyone who would like to have a go at it he now has a YouTube video giving detailed instructions. To see just see him do the back hollowing cut start looking at the 1:00min mark ...

View: https://www.youtube.com/watch?v=_KdPGAqXOds

Note: Richard still follows his back hollowing cut with some flat scraper work to complete the inside of his end grain pieces.

And, yes, there is a swag of tools available now if you have the loot to drop on any of those that will also allow you to hollow with the grain on end grain work. However, new turners usually have other tools that they do really need before they start getting into the specialty tools that they may or may not get a lot of use from. Most new turners will have at least a bowl and spindle gouge used in the above methods.

I made my own hook tools for many years before any of the specialty tools came along and I would recommend those as a next step after trying scraping or doing it Richard's way before getting into the expensive stuff. If you are not up to making your own hooks, Michael Hosaluk makes a reasonably priced one that you can add to your own bar. The advantage of making your own is that you can shape them to suit yourself. No doubt there will be a thread on how to do that on the forum.

 

[hockenbery]

Richard's back hollowing cut with the spindle gouge into end grain is definitely a bevel rubbing cut, not a scrape.

Definitely

My little video shows a scraping cut. By definition, a scraping cut is done with the cutting surface of the tool at less than 90° to the wood. Scraping cuts with the bowl gouge done that way are easier to master for the novice turner.

Looked like a pull cut to me with the wing bevel on the wood
On second look i don’t see the long shavings the pull cut would make.

 

[Don Wattenhofer]

I agree completely - I wouldn’t use back hollowing on face grain.

This thread is about hollowing end grain.

How wide of an endgrain bowl have you done back hollowing?

I have done end grain bowls up to 8" diameter however I would only back cut to about 2 to 3" then switch to a ring tool or hook tool.

 

[hockenbery]

I have done end grain bowls up to 8" diameter however I would only back cut to about 2 to 3" then switch to a ring tool or hook tool.

That is pretty much what I said in my earlier post.

 

[Dean Center]

For those wanting to learn Richard's Back Hollowing, it really helps to try it with a large enough opening that you can see what you are doing and make adjustments. Eventually, you may be using a 1/2" hole as your 'tool rest'.

The other tip I would make, after watching the Raffan video in Neil's post above, is DON'T STICK YOUR FINGER INSIDE WHILE THE WOOD IS TURNING AND THE TOOL REST IS IN PLACE. If you're Richard Raffan, you can do what you want. For the rest of us, it's a great way to break your finger or have major flesh ripped off. (Note the fresh bandage on his hand in the video--even turning Gods bleed!)