Attaching bowl blank to wasteblock

"Russ Stanton" wrote: (clip) Would double side tape from a woodworking store be strong enough for these

^^^^^^^^^^^^^^^^^^ I wouldn't trust it. A failure would most likely result in damage to the blank, and lots of difficulty in recentering.

I suggest white glue.

I would use brown paper bag and white glue. All the bowls I do, small and large, get this process, no failures and easy to seperate. (knock on wood)

Hello Russ,

When turning small bowls like you are planning, I mount a piece of end grain wood in a chuck, turn a tenon to fit the chuck jaws, reverse into the chuck and part off all but about one inch. Turning the end round and flat. I then glue this to the center of the bowl blank with Tite Bond II glue or medium thick CA glue. When the glue has had time to set, overnight for Tite Bond II and five minutes for the CA glue. I mount the tenon back in the chuck with the bowl blank attached. I then turn the bowl inside and out, making sure that I don't get the bottom too thin. After sanding and finishing, I use a thin parting tool to part the tenon from the bowl. I then reverse the bowl in a jam fit chuck, vacuum chuck, or other chuck designed for this purpose, and turn off the remaining portion of the tenon for holding the bowl, sand the bottom, sign it, date it, and note the type of wood. I then apply finish to the bottom portion.

Fred Holder

I'd take white glue and glue on a piece of grocery bag. That paper will hold up fortified with glue on both sides and between a faceplate mounted board and the bottom of the bowl blank.

When you want to part the block and bowl - a chisel press between will wedge the two apart by tearing paper.

Martin

Mart> I want to try turning some small bowls using $ inch square blanks about 2 inches

I went to a turning demonstration. They where using double sided carpet tape and having never seen that done I was quite amazed. It appeared to work very well.

I have turned many drink coasters and such thin objects using double sided tape without mishap. Never tried a bowl.

I tend to agree with Leo and Martin. The double sided tape could well fail and the "paper" joint gives both a strong and easily cleaved joint.

Deb

I've used this process quite successfully. An old hand I talked to at a turning symposium claimed that onionskin (really thin typing paper, might be harder to find these days) makes a stronger but still separable joint. Perhaps that would mean that thinner brown paper would likewise make a stronger joint that thicker brown paper. I doubt it matters much most of the time - I have not had one part company using white glue and paper bags, or white glue and newsprint, but that bit of secondhand lore is available for testing if anyone sees the need. Somehow, not involving a lot of expensive toys associated with advertisers, I doubt fine woodworking would be willing to pay for an article where this theory gets tested.

IIRC lots of folks here also use (or used to use) hot glue for temporary mounts, though I suspect they are weaker than the white glue/paper approach. I've roughed bowl blanks down from square on white glue/paper.

Fred

Thanks for the very complete reply. Is there a reason to turn the waste block from end grain?

Russ

I don't understand why the need to "easily" separate the tenon from the bowl. Can't you just glue the tenon directly to the bowl blank and then part off on the bowl side of the glue joint?

"Woody" wrote: I don't understand why the need to "easily" separate the tenon from the

^^^^^^^^^^^^^^^^^ I see it the same way. The extra effort to soak the paper with glue and position it seem to outweigh any extra parting effort. Don't you have to clean up the fuzz left by the paper?

So the tenon doesn't split along the grain.

You want the grain to be horizontal, not vertical.

I just posted something regarding the direction of the grain, and now I am not sure I understand Fred's suggestion.

If you glue a wood stub (w/tenon) to the wood blank (no paper) then either 1) The stub has the grain horizontally or 2) The grain is vertical.

If horizontal, then you are gluing end grain to side grain, and that's not a strong joint. The joint might fail.

If vertical, then the tenon might split off during the turning process.

Fred - can you clarify?

If you put paper in between, would that make the end-grain to side grain joint less of an issue?

Hello Russ,

Not really any specific reason. Side grain will also work just fine. However, a chuck grips the endgrain better. If you are using a faceplate, I think that side grain wood would perhaps work better.

Fred Holder

That's what was taught in high school wood shop many year ago -- that was B.C. (Before chucks).

We used Kraft paper and white glue, and then screwed a face plate to the glue block. As I recall, at the end of turning, we used a wood chisel to separate the two at the paper line, then finished up with a light sanding to get rid of the traces of glue and paper.

Woodcraft sells a two-sided tape that is for lathe use. It was recommended by the Clearwater store's expert on turning -- I bought some but haven't had a chance to start using it yet.

On Mon, 12 Jul 2010 11:25:22 -0500, Leo Lichtman wrote (in message ):

The attraction is that if a paper joint is used, you can separate the work from the mounting block with a chisel and mallet, taking just a moment. Yes, sanding is required to clean off the paper and glue, but this will still be faster and easier than using a parting tool. In the case of a footed bowl, the paper and glue residue is turned off instead of sanding. To repeat, ease of separation is the reason for a glue and paper joint. respectfully, tom koehler

My comment was directed not to end-grain glue up, but to why you need to "easily" separate the tenon (regardless of grain orientation) from the bowl. Since I always finish the bottom of my bowls by turning a "rim" on the foot and then making them slightly concave within the foot, any waste wood from the tenon is turned away. They also set better than a flat-bottomed bowl.

~Mark.

Well, for one thing, you can keep using the same faceplate block, rather than wasting 1/8-1/4 inch of either block or stock on the parting. Given that the main point is to not waste extra stock, not wasting extra stock (even if it is less expensive stock than the bowl blanks) on faceplate blocks is also good. As someone else mentioned, this is a technique from the time Before Chucks - it also (if you have the time) works Better than Chucks (I've certainly had things creep in my chuck, and that does not happen with a waste block screwed to a faceplate, barring serious disasters.)

If you have a chuck (or a BC chuck substitute, such as a disc with grooves and hot glue) for reverse-chucking the bowl, turning the foot when chucked in reverse is not impeded by half a sheet of paper. And a whack with a blade and mallet is a lot faster than parting off.