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Howdy from Maine!
So, I'm looking to do a long hole bore(16" ish), and I have the Nova System, but am wondering
the following:
Once you have the workpiece centered on the cup point, how does the wood get marked
so that when you punch out the removable point, it's marked on center for the cup?
Do I need to find/make a pointed rod that would poke through the cup for centering?
Make sense?
So far in my youtube/web searching, I haven't seen this demonstrated or explained fully..
Cheers,
Rich
With just medium pressure the cup & point should leave a divot from the point and a ring where the cup met. If it is not marking it just give a little more tail stock pressure. I believe with the cup & point removed you can use a 3/8 bit; with just the point removed from the cup you can use a 5/16".
I think that's what most people do. If you use a rod that will just fit through the quill and center it will be stay nicely centered. To make a perfectly centered point you might spin the rod in a hand drill, drill press, or on the lathe itself if you have a good way to hold it. A dremel or file will work. If there is a tighter restriction in the tailstock than in the center I would probably make a short sliding pointed punch that fits in the center then tap it with a smaller diameter rod through the tailstock.Quote:
Originally Posted by Rich Gouette
The tailstock on the two lathes in my shop will take a 3/8" rod but the hole in the cone on Nova live center is smaller and will take only a 5/16" rod so a long 5/16" pointed rod might be perfect. I put a 5/16" transfer punch in the center then tapped it with a 3/8" rod through the tailstock. It would instead be easy to make a point on a short piece of 5/16" rod then tap it with something longer through the tailstock.
A transfer punch is used by machinists to mark a metal part for drilling/machining. They come in a set of different sizes which is handy to have but probably not worth buying as a wood lathe accessory.
JKJ
excellent gents, thanks much.
I happen to have a nice length of 5/16 rod sitting right in my shop!
:)
Rich
I'm missing something again.
If you are drilling isn't the end of the drill bit pointed? Bring the tail stock close with the bit extending maybe 1/8" to the old divot point then tighten the quill.?
If your drilling with a lamp auger there isn't any point. Seat the cup center with the point firmly. This will leave a center point and should also leave a ring where the cup dents the wood. Then remove the center point and crank the tailstock until the cup aligns with the dents it put in the wood. That should center it. In reality you should turn the piece you are boring after boring and use the holes you drilled as the center. Then when you turn the wood it will automatically be centered.
It may depend on if the work is long and not stout enough to be supported by the chuck alone (i.e. long spindles), the type of drill bit used, the depth of the hole, and the precision needed. The original message doesn't provide details, making it difficult to guess the exact need.Quote:
Originally Posted by Michael Mills
For most holes where the work is well supported by the chuck end only, I simply mark the center, drill a starter hole with a machinist's center drill bit, then drill the hole. If the piece is to be turned after the hole is drilled I make a short wooden plug/mandrel that fits the hole and support the plug and work with the tailstock.
JKJ
I think JohnC found my "missing something". I have not considered a lamp auger with no point.
To the OP, if you have a hard time marking the wood with the cup maybe use a majic marker on the edge of the cup. Bring the cup and point up tight and smooze the live center and stock by hand a little to leave a black ring.