Thread: Steb centres, chuck style vs morse taper

I can't comment directly on your question, but I have a Morse taper one and it has a recess machined in it to grip it in the Chuck jaws. If I am doing lots of spindles it's in the headstock, one offs, in the Chuck.
Rgds,
Crocy.

I guess it boils down to how much and what sort of "spindle turning" do you wish to do. If you are mostly a bowl turner then as Crocy says, its in the chuck for one offs, then a chuck style steb center is probably the right choice.

However if you do mostly spindle turning you will find that a chuck gets in the way quite often. For fine / delicate spindle turning a chuck based steb center is a real PIA!

A chuck based steb center can be a real asset if you like doing offset or thermed turnings. The weight of a chuck can be used to dampen vibrations in a similar principle to a fly wheel if the mass of the offset spindle is small compared to the mass of the chuck.

Thanks gents, good info there. I hadn't even considered a few of those points.

Would I be safe to assume that the type Old Croc is referring to would be the best of both worlds? The ones on offer in the Gumtree sale don't have a shaft and would fit in chuck jaws only.

Originally Posted by simmotommo

Thanks gents, good info there. I hadn't even considered a few of those points.

Would I be safe to assume that the type Old Croc is referring to would be the best of both worlds? The ones on offer in the Gumtree sale don't have a shaft and would fit in chuck jaws only.

Not necessarily! There is still potential for mis-alignment of a steb centre held in chuck jaws. It all depends on the chuck jaw design and the "steb" centre design & if they are compatible, any damage to either etc. There are plenty of copies of the original "Sorby Steb Centre" about now.

Some are horrid, DAMHIKT! Please don't ask which ones to avoid, but I will say the originals are very good and some copies are OK, leave it at that.

Mobyturns you have managed to simultaneously clear and muddy the shallow waters of my understanding in these matters. A rare talent, thanks for giving me more to think about!
Along with the steb centres in the sale I picked up an assortment of jaws for Nova chucks, Nova was already on my shortlist of chucks and being able to grab extra jaws cheap has made my purchasing decision much easier!

Originally Posted by simmotommo

Mobyturns you have managed to simultaneously clear and muddy the shallow waters of my understanding in these matters. A rare talent, thanks for giving me more to think about!
Along with the steb centres in the sale I picked up an assortment of jaws for Nova chucks, Nova was already on my shortlist of chucks and being able to grab extra jaws cheap has made my purchasing decision much easier!

Sorry! I'm honoured to have such a rare talent.

Unfortunately the varying design dimensions of chuck jaw sets of the centre "hole" diameter and jaw thickness, from the various manufacturers requires "brand specific" chuck based steb centres for them to seat correctly / securely.

An MT2 style steb centre can be held in the jaws of a chuck however the accuracy of its alignment is very dependent on the diameter of the cylindrical section on the MT2 spindle and how well it matches the dimensions of chuck jaw sets of the center "hole" i.e. diameter and jaw thickness.

IF the MT2 cylindrical sections diameter is significantly larger than the chuck jaw hole then it will only be held by the "corners or points" of each jaw. The ideal is to be able to close the jaw set up to near its minimum diameter or the "perfect circle" for maximum grip / power and to prevent damage should the steb centre spin in the jaw set. Same principle also applies for the chuck based steb centres.

Look up Stuart Battys "Fundamentals" very informative videos on Vimeo, they will clear the waters for you.

The chuck style steb centre work in the nova and record chuck, just the way they grab the back of the steb centre in the jaws. The vicmarc jaws do not grip them properly.
The best way is to use the 2mt tapered type

Chuck steb centres are good, but as already stated it depends on the chuck that you intend to put it in whether you get a good fit. Like all steb centres they are especially good for spindle turning and yes can be used for small bowls while turning the tennon to hold it in the chuck.

One disadvantage of a chuck held one compared to a morse taper is when working close to the end of a piece the morse taper gives you just that little more room to work on the piece