Did I get lucky?

[Glen Blanchard]

I have had very limited experience using a scroll chuck in the expansion mode, but I hollowed out a vessel this morning that I had this way. About 25% of the way into the hollowing, it dawned on me that I had pretty well finished the foot before I reversed it in the expansion chuck. The thing is, I didn't create a shoulder at the time I turned the foot. For the remainder of the hollowing, I took conservative cuts and was very careful not to hog. I probably checked the snugness of the chuck 30 times. The hollowing went without incident. So did I just get lucky? Should I have turned a shoulder at the foot to be taken off later when I finish the foot?

[Dennis Ford]

The chuck jaws should bottom out inside the recess in expansion mode. I don't see a problem here.

[Bill Bolen]

I've never thought to try a recess on a taller end grain HF but it seems one could get a really nice foot in position befor ever hollowing out. Guess I've always worried about the strngth of the grip and the recess breaking the shoulder area away. Glad it worked out for you though.

[Thomas Canfield]

I seldom use a recess and try to make sure that there is adequate solid wood and no cracks. I did try a recess once in a cross section of Mistletoe burl Mesquite that had some bad cracks (used thick CA) and it did not hold. Another lesson learned, and similar pieces with tenon did work.

[Thom Sturgill]

You do not say what chuck and which jaws. It does make a difference. All of my chucks are teknatool and I use a variety of jaws. MOST of their jaws (unless spigot is part of the name) are better in expansion than in contraction according to the chart they provide in the 'Accessory Jaws Manual'. And by better I mean they are rated to hold both larger diameter and deeper.

All that said, if you normally turn a tenon or spigot and are set up to remove it easily, then consider getting a small (3-4") faceplate instead of a chuck. Do pretty much the same as you would for creating the tenon, but create a slight dish shape on the end of the tenon to mount the plate. That will keep it solidly mounted and not rocking. Center it on the mark made by the tail center, there are tools available to help with that. You will find much less tendency to vibration.

[Glen Blanchard]

Thom - Although I have some Nova G3 chucks, I was using my Oneway Talon. The jaws I was using are not dovetailed, but rather have some retention ridges on them. It sounds as if, as long as they are bottomed out in the recess, there is not a problem. I suppose the only issue is the depth of the recess.

[Dennis Ford]

Thom - Although I have some Nova G3 chucks, I was using my Oneway Talon. The jaws I was using are not dovetailed, but rather have some retention ridges on them. It sounds as if, as long as they are bottomed out in the recess, there is not a problem. I suppose the only issue is the depth of the recess.

Don't forget the issue of the wood possibly splitting due to the forces the jaws are putting on the wood. I do agree that a faceplate is stronger but you don't always need that strength.

[Glen Blanchard]

Well I was reverse mounting it. The outside had already been shaped and I was hollowing. Thus, no faceplate.

[Leo Van Der Loo]

Glen 9 out of 10 pieces I turn are held with a recess, even all my bigger pieces that don't get any tailstock help as they are turned outboard and there is no tailstock.

And I only use Oneway chucks, Talon and Stronghold, I start with a faceplate on rough blanks and after turning the outside I will flip the blank over and hold it with my chuck in a recess.

I do use the woodworm screw and tenon occasionally, to start or hold a blank, as every piece in not the same.

Normally I take pictures of the finished pieces, but occasionally there are pictures taken from WIP pieces, so here a couple of those pictures, showing how I have been holding my pieces with a recess, and for many years already, HTH :)

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[Scott Hackler]

For my preference I don't like a recess UNLESS it's in side grain and it's for a vessel or a bowl when I am using a gouge to remove the stock inside. And I only use a recess for bowls that are larger than 10" or when coring. Using a recess on end grain HF, can be tricky as the forces on the walls of the recess might give way. Hollowing can be and often IS a catchy process. I would never grip the bottom of a blank to hollow it out, through a small hole, with a holloowing tool. I want a correctly sized tenon and I clamp it down HARD (and check it often). Shoot I have had a catch and pulled the blank out of the jaws a tad. Scary indeed. A recess (IMO) would have launched that piece.

[Leo Van Der Loo]

For my preference I don't like a recess UNLESS it's in side grain and it's for a vessel or a bowl when I am using a gouge to remove the stock inside. And I only use a recess for bowls that are larger than 10" or when coring. Using a recess on end grain HF, can be tricky as the forces on the walls of the recess might give way. Hollowing can be and often IS a catchy process. I would never grip the bottom of a blank to hollow it out, through a small hole, with a holloowing tool. I want a correctly sized tenon and I clamp it down HARD (and check it often). Shoot I have had a catch and pulled the blank out of the jaws a tad. Scary indeed. A recess (IMO) would have launched that piece.

Scott I do very few end-grain turnings, but yes the wood is not as strong in that direction, and screws don't hold that well either, so what I have done a time or two is taken a side-grain block and turn a tenon on that to fit the recess in the end-grain piece to fit the tenon, and glued them together, that way I can either a recess in that block or screw it to a faceplate, I glue just the perimeter of the tenon and the butting shoulder, a careful cut with a narrow parting tool when done and there is not much to clean up after, easier than having to remove a tenon from a finished piece.

As for the recess pulling out easier than a tenon, in my experience that is not the case, however I'm turning my way, not your way, and so whatever works for you, you should use, but don't just discard the other ways because as a new or inexperienced turner one has a scary thing happen.

The other thing one should adjust to the shape and type of wood is being turned and the type and direction of the wood grain, it certainly does play a roll :D

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[robert baccus]

Leo, you said it. Consider all the variables especially the wood, and all the methods work. I use as radical a method for long HF's as anyone but I have yet to lose one doing this. Chuck--single screw--very hard wood glueblock--thick CA--green vases to 100#+ and have done many like this. But I am very careful about the details. I have turned bowls/vases over 100# with all these methods and the only troubles were with tenons, not necessarily flying but being knocked out of true alignment. I am always open for new ideas or cc.

[Leo Van Der Loo]

Leo, you said it. Consider all the variables especially the wood, and all the methods w,ork. I use as radical a method for long HF's as anyone but I have yet to lose one doing this. Chuck--single screw--very hard wood glueblock--thick CA--green vases to 100#+ and have done many like this. But I am very careful about the details. I have turned bowls/vases over 100# with all these methods and the only troubles were with tenons, not necessarily flying but being knocked out of true alignment. I am always open for new ideas or cc.

Robert as I said, the shape and type of wood being turned and the type and direction of the wood grain does play a role in deciding how to hold a piece of wood, "one size doesn't fit all" is applicable here to.

The other thing I always take extra care with is that my tenons/recesses (for my Oneway chucks) are exactly square and clean, the size is not as important with the regular Oneway chuck jaws as they will hold equally well over the full range of the chucks capacity, so I'm not held hostage by the dovetail dilemma of having to make my tenon/recess fit the jaws rather than my bowl or whatever, but a clean, straight and square turned recess will hold well and secure.

Of course catches are few and far between and being careful and patient will serve one well, of course I turn for my pleasure and I will take the extra time if needed, rather than hog and rush and have nice piece fly and having to start over again IF I didn't get hurt doing that :rolleyes: