Nova SN2

[Brian Grenia]

I already have the SN2. Woodcraft is having a nice sale and I'm thinking of picking up 2 more so I don't have to change jaws as often.

However, I want a strong/big chuck for coring large bowl blanks. I'm looking for input on the following:

Does the SN2 with larger jaws have sufficient power to hold blanks while coring? If I stay with Nova then all my jaws should interchange (right?)

Or for coring should I step up to a larger chuck. For example the Nova Titan or ONEWAY Stronghold or Vicmarc?

I'm probably going to get 2 more SN2s anyway (I already have jaws), but I'm looking for input on the 3rd-- the big one.

 

[Brian McInturff]

How large of blank do you plan on starting with?

 

[Brian Grenia]

I ran into a 17ft cherry log. 21 inch diameter. Probably turn down to 17 or 18 initial shape

 

[Mark Levitski]

The SN2 would work just fine for this, although unless you're turning whole-log endgrain, 21" w/ pith removed will give you a lot less than 17-18". With my 16" swing lathe, I routinely core w/ the SN2 no problems. If you're turning a lot of pieces, I'd go with the same chuck bodies and enjoy changing only chucks and not jaws all the time. Although I sometimes use the 130mm jaws, I usually use the 100mm powergrip for most larger pieces, then turn the spigot off to finish.

 

[Roger Chandler]

For my large blanks, I use the 100mm power grip jaws........never had a problem, and they hold super great.

 

[Bill Blasic]

I hope to see the Titan re-released sometime in the near future. They did it with the Ornamental Turner so I'm hoping.
Bill

 

[David Wilkins]

The sn2 should serve you just fine.

For what it is worth, I was going to purchases a couple of extra chucks for the same reason. Then a cordless electric screwdriver arrived one Christmas, swaping jaws is now easier than chucks.

 

[MichaelMouse]

If you use your tailstock, you should have no problem with the 100mm. If you don't, you'll need developed skill with the knives or a faceplate. You might consider cheating your way a bit further back with an extended quill / extended cup center combination when you do.

 

[Harry Robinette]

I use my Vega 2600 and the McNaughton coring system with my Nova Titan 5" chuck. But only for blanks over about 22" dia and 10" and over thick.
All the other blacks I use Super Nova or Super Nova 2 with 100mm jaws. Seems to work pretty good so far.

 

[Odie]

I'm probably going to get 2 more SN2s anyway (I already have jaws), but I'm looking for input on the 3rd-- the big one.

Getting multiple chucks is a very nice convenience to a turner. I have three Oneway Stronghold chucks, and now that the expense is out of the way......I'm mighty glad I was convinced by other turners that multiple chucks are worth it.....

These are not my first chucks, as I've gone through a progression of chucks to come to these three Strongholds as my main "go to" chucks. My first chuck was an original Nova.....long now out of production. I then used both small (3 1/2") and large (5 1/2") Vicmarc chucks for a time. These Vicmarcs had the "tommy bars", and the more current versions of keyed chucks are much more convenient.

It is my opinion that the Nova was too small, although fully capable of holding the maximum diameter my lathe was capable of......16". If this makes any sense to you, I sort of think it's on the same of level as pounding a nail with a little hammer.......sure, it might get the job done, but the bigger hammer is sooooo much better!

I was very impressed with the quality of the Vicmarc chucks. When I switched over to my first Stronghold chuck around 1992, or so......the criteria I used for that decision was mainly the assortment of jaw configurations and sizes that were available at that time. The Stronghold far outclassed the Vicmarc on that basis. I feel the Stronghold does just as good a job as the Vicmarcs......although, I felt the Vicmarcs were more impressive to behold!

For my three Stronghold chucks, I keep one chuck permanently mounted with the Mega Jumbo Jaws. The second Stronghold has the No. 2 standard jaws permanently mounted. This set of jaws is the most versatile, and probably does 90 percent of the bowls I do. The third Stronghold is my "do-all" chuck that is the one that I use to interchange all the other jaws.....when I have a special need for a seldomly used set of jaws.

I've got most all of the jaws available. Some of these, I've never used, but it's nice to know they are there and available at the time when that need will materialize.

I am a believer in the holding power of the serrated jaws. This, I wouldn't do without......although, this discussion has come up before, and my opinion about that doesn't agree with some of the other turners who feel the non-serrated jaws are much more useful without the jaws marking the wood in any way. I do understand that sentiment, but feel the serrated jaws have a safety advantage, as well as enhanced gripping power.......so, I guess that controversy is best answered by the individual.......rather than group consent!

If you do get multiple chucks, I have no doubt someday you'll be thinking you are glad you did.....I know I do all the time!

ooc

 

[Bill Blasic]

I agree with Odie on one point and that is that more chucks are better. I have and use many Nova chucks. From the Tommy Bar chucks to the Titan and on all I use the dovetail design jaws for holding my work, not because it doesn't mar the wood but I feel the holding power (Mechanical Advantage) of the dovetail is superior. I have always stated that if you buy one of the three best systems (Nova, Vicmarc or Oneway) you will not be disappointed. I chose Nova and the fact that all the jaws fit all the chucks (except the Titan Power Grip jaws only fit the Titan) has worked nicely for me (that plus they all open and close in the same direction). Keep an open mind and try both the serrated and dovetail jaws to see what you prefer.
Bill

 

[MichaelMouse]

OD, the size of the chuck body doesn't have anything to do with its hold. It's the jaws. So the 50mm on the classic Nova is the equivalent of the 50mm on anything in the line. Probably why Teknatool's legal department gives max recommended load for jaws not bodies.

I have looked and looked, and I still can't find any application where a symmetrical wedge does anything but spread the softer component (wood) symmetrically. If they were designed with 90 degrees to the face of the jaw on the top, and a slope facing the nose, they'd hold a straight-cut tenon up against the shoulder like a regular dovetail. Anyone seen such a thing? If you make a dovetail cut, the tightening jaws will even help draw the nose to the shoulder or mortise bottom.

Users of chucks with available dovetail holds should think of them as what they are, a wedge to snug the nose of the jaws tight to the bottom of the mortise or tenon. It'll keep them from doing silly things like over tightening in a vain attempt to improve the hold. Sadly, there appear to be a lot of people whose misapprehensions translate into misleading advice.

Note, as well, that if their purpose were to keep the piece from rotating, the chuck jaws would be designed like a pair of pliers, with the "serrations" running at 90 degees.

 

[Odie]

OD, the size of the chuck body doesn't have anything to do with its hold.

Well, actually it does, MM! The chuck body is what puts the power behind the jaws. If you're familiar with the internal workings of the scroll chuck, you'll find the bigger chuck body will have bigger, more substantial scroll......and this relates to overall strength and power capabilities. If the chuck body had no influence on strength and power, then there would be no point to making bigger chucks at all!

Seems to me, I remember you are one who uses chuck jaws in the expand mode.....into a recess. For this, the power capability of the chuck might never be realized, because this method of attachment is restricted by the amount of power behind the jaws the wood can handle before it will crack. For spigot attachment, you can crank down the jaws with much more power without that concern......so, in your case, I'd say you're thoughts are correct for the methods you use, but in my case, the added power of the bigger chuck is welcome for turnings that are large in diameter, and deep.

Note, as well, that if their purpose were to keep the piece from rotating, the chuck jaws would be designed like a pair of pliers, with the "serrations" running at 90 degrees.

This is a correct assumption on your part, MM. The serrations are not there to prevent the wood from spinning in the jaws at all. They are there to prevent any bump, catch, or force from disturbing the alignment of the wood to chuck. Once that happens, you'll never get the same alignment again. I have Stronghold jaws without the serrations, plus the Vicmarc chucks and original Nova chucks were strictly dovetail.......it was very apparent, right from the beginning, that a minor bump or catch would be enough to disturb this critical alignment. Even a very small amount of movement was enough to be very aggravating, especially if in the process of finish turning.

This is why I prefer to utilize the serrations, although I may go through many bowls before their advantage is actually used/needed.

ooc

 

[MichaelMouse]

Ya fell into the trap again. It's like the old joke - you only have to outrun your buddy, not the bear. Once the connection is made between metal and wood it cannot be improved by cranking down on the key. There are only two results possible - destruction of the wood (buddy) or the chuck.

Chuck users need to avoid this kind of mental trap, especially wedge users. Matter of plain fact, if you can size to get full contact you minimize the load at any given point, you need even less crank on the chuck for best effect. One of the reasons I use the mortise is that it can be made to optimum wet and returned to optimum after drying. Tenons have to start a bit over, where you may have to load eight points in the circle to wedge the nose firmly into the shoulder. Be foolish to overload and deform, as you yourself mention.

 

[Odie]

Ya fell into the trap again. It's like the old joke - you only have to outrun your buddy, not the bear. Once the connection is made between metal and wood it cannot be improved by cranking down on the key. There are only two results possible - destruction of the wood (buddy) or the chuck.

Chuck users need to avoid this kind of mental trap, especially wedge users. Matter of plain fact, if you can size to get full contact you minimize the load at any given point, you need even less crank on the chuck for best effect. One of the reasons I use the mortise is that it can be made to optimum wet and returned to optimum after drying. Tenons have to start a bit over, where you may have to load eight points in the circle to wedge the nose firmly into the shoulder. Be foolish to overload and deform, as you yourself mention.

A trap?......Well, MM, I'm not surprised at all by your response.

However, I prefer to consider my conclusions a matter of the culmination of my experiences......and, by the same token, I feel the same applies to you, so I don't see this as an issue that is differentiated by a "right and wrong" concept. To the contrary, actually!

There are things that can be seen in the "right vs wrong" prism.....but, this isn't one of them......and, I hope you don't see my comments as being from a point of view that all I express on these forums, can, or should be held as being what others should believe, or do. Basically, I'm only giving an opinion......just as you are. The main thing to consider here, is to try and understand we all travel an individual path down the road to enlightenment. All of us choose our own methods of getting there, and there are just as many and varied methods, as there are individuals........

Later, MM.......

ooc

 

[Mike McDonald]

"Listening" to you two going back and forth is rather interesting. Both of your opinions sound completely reasonable, to me.

--

I'm very much a newbie, but I've had no end of trouble with my Nova2 - all user/ID-10-T errors, I'm sure.

I generally rough between centers, forming a tenon in the process. When I try to go to the scroll chuck, one (or both) of two things typically happens:

a) The piece flies out of the scroll chuck while I'm trying to turn it. I'm guessing this is because of too-aggressive cutting / dull tool / getting a catch. Actually had the tenon break off one or two pieces, but I think that was because of punky wood. This is been happening less as I've gotten more experience.

b) The jaws crush the tenon, the piece is way off-center as a result, and I have to significantly re-work it to true it up.

Does anyone make a scroll-chuck with a torque-wrench built in, so that it's impossible for me to over-tighten it ?

 

[MichaelMouse]

Lots of things you can do wrong, of course. Are you making the tenon too long and bottoming out inside the jaws rather than fitting tight up against the shoulder? Part of the mentality that sees things as a grip when they're really a wedge thinks the longer the tenon the better. Simply not so. Banish it from your brain and shorten the tenon so that it's wedged, not bottomed and grabbed.

If you decide to go inside a mortise, remember that you want to wedge the nose tightly against the bottom of that mortise. Deeper is NOT better, and can split you out if you go below the dovetail cut on the jaws. I'm a mortise guy, so the pictures I have are for that option. http://i35.photobucket.com/albums/d160/GoodOnesGone/ContactSheet-1-1.jpg I also, as you see, keep things available between centers until the big wet heavy and unbalanced part of the work is over. Defensive tactic from my original non-scrolling Masterchuck that threw things at random. You want to snug so that you have no flop when you back off the tail, and the piece is rotating centered.

No excuse in the world for a freshly made shouldered tenon or wedged mortise to NOT center perfectly, so don't accept it. Squeezing an improperly seated chuck with improper bottoming is suicide. Back off, clean up what's in the way - usually some wet or rough wood, and reseat. As soon as it resists your turn, stop, check for center. If it is, the final snug is yours. Remember, you only need resistance strong enough to remove a shaving - outrunning your partner - not a white-knuckle crank.

If you use ring-porous woods like oak or ash you can get yourself some trouble by putting that weak area at the bottom of your tenon or mortise. I like to put some water-thin CA in to fill those vessels. Give extra cure time on acid woods, and remember to cut or scrape your tenon/shoulder back to round and flat, ditto for innies.

 

[Bill Blasic]

One thing I might add is that when I turn the outside of my bowl I finish it right through the sanding. Having already made a tenon for turning it around the very last cut I make before turning it is to take a fine cut on the tenon to true it up to the work I've done to that point. Then like Michael says I grip on this tenon without squeezing it to death and I get no or very little runout.
Bill