Safe or un-safe?

[Deane Allinson]

I am learning to turn by doing it and figuring it out by trial & error as I go along. I have been turning smaller bowls etc. and now I have some larger blocks. I have a 10" dia x 4" thick walnut blank. I have glued a 4" dia waste block to the 10 1/2" blank and then screwed both to a 3" face plate. I glue an 1/8" bead of glue around the outer 1/2" of the waste block. When finished with the bowl I part off the bowl by cutting past the glue line.
This works pretty good for me on smaller pieces but wonder how this will work on larger pieces. I don't want screw holes in the bottom of the finished piece and am trying to get as much out of the block as I can. And I don't want a big chunk flying off.
Is this standard practice or accident waiting to happen???
I live in the middle of nowhere so there are no clubs or other turners around.
Deane

[Dan Hintz]

Is there a reason you're not turning a tenon and throwing it in a chuck?

[Stephen Walker]

Deane,
I turn my bowls with a recess on the bottom. Screw the face plate to what you want for the top of the bowl, turn the recess,and shape of the bowl, then finish. Then I take the faceplate off, reverse the bowl onto my chuck, hollow and finish the inside and rim. Just have to remember how deep you cut the recess and don't hollow to close or its a funnel.

Steve

[Deane Allinson]

Is there a reason you're not turning a tenon and throwing it in a chuck?

No chuck. Just a 10" 1940's Delta Milwaukee, and harbor freight tools + 1 decent bowl gouge and a 3" face plate.
Deane

[Dave Ogren]

I do the same as Stephen Walker does. Works great, no loss of wood as you would get with a tenon. Some people do not like the recess ??? Try it, it might just be the answer for you.

Good Luck.

Dave

[Wally Dickerman]

A 4 x 10 blank is not too large for a glue block if....As with any glue joint, both surfaces must be true and flat. There should be sufficient glue to have squeeze-out. Many glue block failure are a result of not enough glue. If the wood is wet, use med or thick CA glue. Titebond doesn't work well with wet wood.

Don't let anybody tell you that you must have a chuck to turn bowls. You don't. Glue blocks and faceplates work very well. The 4-jaw chuck that's so popular today didn't exist before 1988. We turned a lot of bowls before that.

[David E Keller]

I think you're safe doing what you're doing if the glue block is well fixed. I've never parted off a bowl, so I would probably reverse the piece against a jam chuck and turn away the glue block to finish the bottom... That would keep me from having to catch the bowl as I came free. I've used a chuck for most of my bowl turning, but I finish the bottoms by reversing the form against a jam chuck.

FWIW, the Grizzly chuck(Vicmarc clone) is a nice chuck for the $109 price tag... I have several of them with different jaws, and I've been happy with them.

[Wally Dickerman]

I think you're safe doing what you're doing if the glue block is well fixed. I've never parted off a bowl, so I would probably reverse the piece against a jam chuck and turn away the glue block to finish the bottom... That would keep me from having to catch the bowl as I came free. I've used a chuck for most of my bowl turning, but I finish the bottoms by reversing the form against a jam chuck.

FWIW, the Grizzly chuck(Vicmarc clone) is a nice chuck for the $109 price tag... I have several of them with different jaws, and I've been happy with them.

You have to be brave David. Live dangerously...I use glue blocks a lot and my students use them. I've parted off hundreds of bowls along the glue line. A little off the glue block and a little off the bowl. Can't remember ever losing one. Depending on the size and weight of the bowl, I part it down until the glue joint is about the size of a nickel. Pop the bowl with the heel of my hand..if it doesn't come off, I part it to the size of a dime. That usually does it. Nearly always the glue joint holds and wood separates. Proof of a good glue joint.

[Scott Hackler]

Although my glue blocks are turned with a tenon on the opposite end (short piece of stock so no extra wood for its own tenon), I almost always part the glue line at the end. I only started doing this because I can use most glue blocks twice! (and noone told me not to do this)

[James Combs]

I have several chucks but there are still occasions where I use a glued on waste block. Saving as much of the blank as possible is one of them. The only difference in this and your method is I will clamp the waste block in chuck and you will screw a face plate onto it. I have always used CA to glue on my waste blocks. I did loose one blank due to a failed glue joint but it was my fault. I got into too big of a hurry to turn the blank, the CA was not fully set. When it popped off there was still liquid thick CA in the center of the joint. So to answer your original question, yes it is safe if you do it right. Just make sure your glue is dry and that you have a good smooth joint between the waste block and the blank and of course the larger the blank the larger the waste block.

[David E Keller]

You have to be brave David. Live dangerously...I use glue blocks a lot and my students use them. I've parted off hundreds of bowls along the glue line. A little off the glue block and a little off the bowl. Can't remember ever losing one. Depending on the size and weight of the bowl, I part it down until the glue joint is about the size of a nickel. Pop the bowl with the heel of my hand..if it doesn't come off, I part it to the size of a dime. That usually does it. Nearly always the glue joint holds and wood separates. Proof of a good glue joint.

When you do this, Wally, do you finish the bottom by hand off the lathe? Vacuum?

I've used glue blocks quite a bit for miniature HF's, jewelry, and other small items(under 6 or 7 inches)... Perhaps I'll give it a go on a larger piece if the wood is particularly pretty or expensive. I just can't see the appeal with 'regular' wood and current chuck technology. It does beg the question... Is there such thing as a bowl that's too large to just part off?

[Baxter Smith]

Deane, I met a woodturner this summer in Prince Edward Island who said he has been turning as a business for more than 40 years. He still only uses glueblocks.... for everything. 16" bowls, platters, segmented work 3 feet tall, you name it and he had it in his showroom. His bowl storage room had more than 500 waiting to be finish turned. All of it on glueblocks!

[Curt Fuller]

It does beg the question... Is there such thing as a bowl that's too large to just part off?

I don't part anything completely off with the exception of small spindles. I guess I just don't trust myself to catch it before it does a couple ricochets around the garage. I've always done it like Wally described and if it's endgrain I just get it down to the point where it gets risky to go any smaller and them stop and cut it off with a small saw. Then I either reverse it to finish the bottom or just sand off any nub.

I've also had far more tenons break than I've ever had glue blocks not hang on. If I have a particularly questionable piece of wood I'll usually glue on a waste block just because it seems stronger. So I would say that a glue block screwed to a face plate is safer than a tenon in a chuck if it's done right and the glue gets the proper cure. However, from a safety aspect I would suggest that anyone, new or experienced, get in the habit of learning to stay away from the obvious line of fire that a piece of wood will follow if it comes loose and then make it a habit to wear face protection all the time. It just seems like it's always the piece of wood that you're not worried about that gives you a black eye or knocks a hole in the shop wall.

[John Beaver]

A 10" bowl blank at 600-1000 r.p.m. is generating a lot of force. I would put glue on the entire block if I were doing it your way. Your method might work most of the time, but one good catch could spell trouble if the joint isn't perfect. If you have a tail stock, then reversing the bowl to a jam chuck and turning off the block should be almost as easy as your current method.

[Wally Dickerman]

When you do this, Wally, do you finish the bottom by hand off the lathe? Vacuum?

I've used glue blocks quite a bit for miniature HF's, jewelry, and other small items(under 6 or 7 inches)... Perhaps I'll give it a go on a larger piece if the wood is particularly pretty or expensive. I just can't see the appeal with 'regular' wood and current chuck technology. It does beg the question... Is there such thing as a bowl that's too large to just part off?

I don't know how large I've gone with bowl size and glue blocks. Perhaps 14 or 15 inches. I've been using glue blocks for a long time.

Something I haven't mentioned is the use of a tenon with a glue block. I never use a glue block with end grain pieces without a tenon. I just don't trust an end grain glue joint. I cut a small shallow tenon on the blank and a corresponding hole in the glue block. Makes a much stronger glue joint. With that type of glue joint I part the piece part way off and complete it with a small handsaw or coping saw.

The bottom can be completed using your regular method. Vac chuck, cole jaws, jam chuck or whatever.

From what I've read here I think that some folks are misunderstanding how I remove the piece from the glue block. The bowl doesn't go flying at all. After parting it nearly off, I hold the bowl with one hand and pop it off with the heel of my other hand. Have't lost one yet. The glue joint nearly always holds. What's remaining of the glue block breaks.

For those that are wondering, a faceplate is the strongest and safest way to secure a bowl blank. I've seen blanks that weighhed several hundred pounds secured using a faceplate directly on the wood.