Bowl gouge use, Hollowing, grind issue, tips.

[Chris Studley]

I find myself "Monday morning QB-ing" my weekend's efforts in my head. Since my only real time to turn is on the weekend I want to turn for every last second I can and come up from the basement with something cool to show for myself. Since there somethimes is a "fit it all in" mentality there are plenty of mistakes to mull over.

Having spent the weekend turning green bowls, Hits and misses. I really found catches to be very easy to come by. First off, I assume tha green wood to require a bit more in the way of tool control since it is easy to cut, this I would presume willl come with more practice. Second, I know that being pressed for time is a recipie for disaster, although part of a successful green piece turned to finish is timing. Third being new to the bowl gouge. I think some basic bowl/gouge questions are in order.

Question 1: Gouge Presentation. I only really could get the BG to work one way. Starting from the bowl rim(or picking up a previous cut), flute aiming mostly toward 2 o'clock-ish. The center portion was especially tedious(i suspect tool height is an issue here (see below). I also thought that I would be able to scrape using the cheek of the fingernail Grind. I swear I've seen this done, inside or outside, but was a sure fire catch for me every time I attempted it. My Homemade gouge grinder(likely probably part of the problem) for the Grizzly Tormek Clone is producing a grind something like this. The support post is 12mm which is close to 1/2" but there is a little wobble. The grizzly straight jig that I have uses split plastic rings to reduce the hole to the proper 12mm size.

Bowl Gouge Grind.JPG

Notice the high, rounded Cheek w/ a little curve toward the nose. If I'm not mistaked it should be more straight-ish like the dotted line indicates.

I suspect this is why the cheek was catchy. I ground it a bit more being careful to not flex or "wobble" the jig. It got somewhat better but still not quite straight. I need to either break down and eat the $90 for the tormek Jig or rethink the homemade jig a bit. The concept is so simple that I have a hard time with it being $90.

Question 2: Tool rest orientation/tool height (inside of bowl). First, height; I alway shoot for about even w/ the center(or a hair below) is this about right? For a gouge, scraper etc. . As far as orientatoin, as I got deeper it got more touchy so I positioned the tool rest into the bowl. b/c of the shape of the bowl I found that I needed to have to tool rest fairly high to clear the tool rest as it widens toward to post. This wasn't too bad w/ the scraper but the gouge was harder to control. by the time I'm at this point I have some time invested in the bowl and the thought of a catch is nerve racking.

I saw a post from someone, yesterday I believe, regarding One-at-a-time vs multiple projects. Being that I'm more a weekend guys I have been on the one-at-a-time route. I think that I need to move to the Multiple project method to reduce some of the bad habits I have regarding rushing things.


Any feedback or comments are appreciated.

[Jamie Donaldson]

This is a long series of questions Chris, so I will attempt to compress some of the answers. The profile of the BG wings must be slightly convex or straight, depending on application, but I'm betting your catches when attempting to shear cut on the interior of a bowl are due to the attitude of the gouge, or more accurately, the gouge handle. Shearing must be done with the cutting wing presented on a diagonal to the wood, with the handle down at about a 45 degree angle, NEVER flat to the wood at centerline. Sticking the wing into the wood flat at centerline or below can yield the mother of all catches, often dismounting a blank in multiple pieces, and causing wirty dords to fly as well! When initially hollowing out a bowl, the handle should also be down to a lesser degree, and the bevel rubbing push cut will then allow the flute to be open at about the 2 o'clock position, and aimed toward the center of the bowl.

[Bruce Pratt]

Chris,

That portion of the gouge above the dotted line is a killer. Some time back the grind on my Ellsworth got a bit of that "cheek" and I was catching on everything. Reground it straight and things got a whole lot better. If you want to arrange some time to work together on a weekend to sort out some of this stuff, PM me.
----------
Bruce

[Chris Studley]

@ Jaime - Handle down leaves the tool "pointing" upwards diagonally so at what level should I optimally be in contact w/ the wood, a little above center? This would have my tool rest relatively low to allow for the Pointing upward?.. As far as the intitial hollowing. I found the closer to the center the harder it was to control. I have an oland style tool I made and this worked pretty well bit i thought the gouge should have been btter than it was. (probably a technique issue).

@ Bruce - What did you find was the cause of the cheek when you got rid of it? I have a wobbly homemede jig, how did it show up for you?

The other thing is the tool rest. I want to get it in there so I'm not hanging out that far. The gouge is tolerant of so hang out but my dinky HF scraper isn't really beefy enough to hang out very far. Since the stock tool rest expands as it gets closer to the post It is much higher than I think it should be as I get t in there. What kind of tool rest should I consider?

[Bruce Pratt]

Chris,

The cheek came from not paying attention to details/ingnorance when grinding. I've got an Ellsworth jig, and I was just not using uniform pressure when grinding. If we can get together for a couple of hours on a weekend, I can get you sorted out on most of these issues.

Bruce

[Chris Studley]

@ Bruce thanks for the offer. I will likely take you up on it in a few weeks or so.

[Jamie Donaldson]

Chris- the tool rest should be adjusted to allow the tool to cut at or slightly above center line of the bowl, but don't go to extremes with the tool handle too far down. The gouge is much more efficient at clean cutting, because Oland style tools are scrapers, and Knud Oland was my first turning teacher in 1986! If you have access to an experienced tool sharpener/turner, jump at the opportunity, because individual instruction is a great learning opportunity.

[Mark Levitski]

Chris,Try rough grinding your dotted line w/ the flute face down against the grinding wheel first to get the intended profile. Then go to the jig to sharpen those wings. As far as I know, there is no safe/easy way to shear scrape the inside of a bowl w/ the bowl gouge. You can resort to a scraper or use an interior finish cut (bowl gouge) such as described by Ellsworth in his book.If you're turning green for twice-turned (for drying), then don't get too picky with the finish at this stage anyway--it gets re-turned later.Get with someone nearby for some one-on-one. It'll help a lot. Mark

[Chris Studley]

Cool... Thanks Jaime.

I only used the oland because the center was giving me trouble.

[George Morris]

A great Vidio is Bill Grumbine 's check out his site at wonderful wood. join a local club check out AAW site for one near you. Someone will give you some one on one help. G

[Bill Boehme]

Having spent the weekend turning green bowls, Hits and misses. I really found catches to be very easy to come by. First off, I assume tha green wood to require a bit more in the way of tool control since it is easy to cut, this I would presume willl come with more practice. Second, I know that being pressed for time is a recipie for disaster, although part of a successful green piece turned to finish is timing. Third being new to the bowl gouge. I think some basic bowl/gouge questions are in order.

Green wood is more forgiving of mistakes unless you are making really big mistakes like biting off more than you can chew -- or bigger bites than the gouge should be taking. You are rushing to make a bowl before you know how to turn. Turning is supposed to be therapeutic and relaxing not a mad sprint to the finish line. Try thinking about seeing how small shavings you can turn and how long you make streamers without worrying too much about the project. Look at the bevel and its relationship to the wood. Look at the point where the gouge contacts the tool rest -- is it directly beneath the point where the wood is being cut?

Turning posture is important. Don't stand rigid and move your arms. Tuck your elbows into your body and move your hips. Before making a cut, rehearse your starting and finishing positions. Now place your feet so that you can just shift your weight and not move your feet.

Question 1: Gouge Presentation. I only really could get the BG to work one way. Starting from the bowl rim(or picking up a previous cut), flute aiming mostly toward 2 o'clock-ish. The center portion was especially tedious(i suspect tool height is an issue here (see below). I also thought that I would be able to scrape using the cheek of the fingernail Grind. I swear I've seen this done, inside or outside, but was a sure fire catch for me every time I attempted it. My Homemade gouge grinder(likely probably part of the problem) for the Grizzly Tormek Clone is producing a grind something like this. The support post is 12mm which is close to 1/2" but there is a little wobble. The grizzly straight jig that I have uses split plastic rings to reduce the hole to the proper 12mm size.

Do NOT try using the bowl gouge to shear scrape the interior of a bowl. When using a scraper on the interior of a bowl, the contact of the scraper must be ABOVE the center line, but the tool should be oriented downwards (the back of the handle should be higher than the tip of the scraper by a couple inches or so). If you try to scrape below centerline, it is a sure-fire guaranteed way to get a spectacular bowl busting catch.

When using the BG, keep an eye on the bevel and make sure that you are slicing and not scraping the wood.

Notice the high, rounded Cheek w/ a little curve toward the nose. If I'm not mistaked it should be more straight-ish like the dotted line indicates.

I suspect this is why the cheek was catchy. I ground it a bit more being careful to not flex or "wobble" the jig. It got somewhat better but still not quite straight. I need to either break down and eat the $90 for the tormek Jig or rethink the homemade jig a bit. The concept is so simple that I have a hard time with it being $90.

For a beginner, straighter is easier. First of all, use a larger bevel angle at the tip of the tool.An angle of 60° or 65° should be about right. Since you are using a Tormek or Tormek rip-off, try this: α = 65°, JS = 4.5, P = 2⅞". These will give a very good approximation to the Ellsworth grind and better than the settings that Tormek recommends IMHO. Remember that any jig only determines the angles and not the shape. If you over-grind, the result will be thin curved side wings.

Question 2: Tool rest orientation/tool height (inside of bowl). First, height; I alway shoot for about even w/ the center(or a hair below) is this about right? For a gouge, scraper etc. . As far as orientatoin, as I got deeper it got more touchy so I positioned the tool rest into the bowl. b/c of the shape of the bowl I found that I needed to have to tool rest fairly high to clear the tool rest as it widens toward to post. This wasn't too bad w/ the scraper but the gouge was harder to control. by the time I'm at this point I have some time invested in the bowl and the thought of a catch is nerve racking.

For inside turning, adjust the height of the rest so that the point of the gouge is precisely on center. This will enable you to get the little nub at the center of the bowl. You can go slightly above center, but never below -- until you become very proficient. On the exterior you can move the rest a bit lower if desired, but centerline for the tip of the tool is a good place for a beginner. Your tension over getting a catch is perfectly normal, but also a major factor in getting catches. It is a Catch-22 if you will excuse the pun.

[Chris Studley]

Thanks for the thorough response Bill.

I will keep these things in mind. I will likely re-read this before turning this weekend.

I appreciate all of the pointers from everyone here.