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Pat
27th May 2010, 07:04 PM
Anyone in Australia sell these dodads . . . Center Markers (http://www.woodturnerscatalog.com/store/Lathe_Accessories___Screw_Centers___Faceplates___Center_Marker___center_marker?Args=) to fit M30 faceplates. Otherwise I'll give my tame Fitter Mechanist a call. Some Ally bar with a steel pin of the appropriate sizing.

Durdge39
27th May 2010, 07:43 PM
Not sure where to get one in Aus, but if I knew the dimensions I could likely make one for you. Send me a PM if you're interested.

Jim Carroll
27th May 2010, 08:17 PM
Not really needed Pat.

I am not sure why the would want to mark the side where the face plate is as it it the other side of the blank that you would want the mark on.

One use for it may be to centralise the face plate, mark the centre as usual then put the pin in place on the centre then the collar over the pin and then the faceplate over the collar, you now have the faceplate in the centre of the bowl blank and not of to one side as can happen.

The side where the faceplate is on will be turned away.

When turning the outside of the blank and you have set up the spigot on the base of the blank you can bring up your live centre with the pin & ring type and mark a ring on the base . This helps in aligning the bowl when you use bowl jaws or a vacum chuck as you have a central referance to go buy.

If you use a cone centre this may still push the bowl sideways and not run true.

mkypenturner
27th May 2010, 08:22 PM
just had a look i reckin all you need to do is turn a piece of hardwood down to fit the thread and have a small hole in middle for a old screwdriver sharpened to a point or a steel rod of some type
well thats my thoughts

troy

Pat
27th May 2010, 08:27 PM
Boys, just toying with an idea to make sure my faceplates are accurately centered. I've already thought of the hardwood dowel turned down to 25.5mm and bored out to allow a 100mm nail @ 3mm to act as the pin. I might have a play over the weekend.

KenW
27th May 2010, 08:58 PM
Pat, I use one all the time. I made mine by turning a piece of wood to be a clearance fit inside the faceplate thread, then put a nail in the center, to find center of job.

joe greiner
27th May 2010, 09:17 PM
Drilling a hole precisely in the center of a dowel is not as easy as it seems, because wood grain may persuade the bit to drift. Better to drill the hole in a slightly over-sized dowel; use a snug-fitting rod to secure the dowel - the same size nail is sufficient, if long enough. Mount the rod/nail, with dowel, in a chuck (on drill press, if necessary), and turn the dowel to its final diameter. The hole is thus precisely centered.

Alternatively, use the drill bit as the chucking rod, place a dab of hot-melt glue at the exit, final turn and sand the dowel, and scrape off the glue for removal. A bench-mounted drill press can be laid on its back, to simulate a horizontal lathe, if it's more comfortable that way.

Cheers,
Joe

Grant Mack
27th May 2010, 09:21 PM
Pat,
On the Teknatool site under Projects they give instructions on how to make a centre finder for their faceplates out of wood and a nail.
I have made one and it works.
I am sure the principle could be adapted to what you are after.
Cheers
Grant MacKinnon

Pat
27th May 2010, 10:07 PM
I just had a thought, yes I know that it's very dangerous for me to think, I might actually do something. I happen to have a Die for M30x3.5, so Plan A is to turn a "dowel" to the requisite size (30mm according to my copy of the Engineer's Black Book), cut threads for 15-20 mm to locate the "dowel", drill the hole for the "pin" and Bob's your uncle and Mary is undecided. Of course being Plan A it will be revised and revised and revised until I get a finished product or a case of the :upset:

TTIT
27th May 2010, 10:48 PM
Check through your existing bits and pieces first Pat :; - I found that one of my drive-centers is an ideal fit inside the faceplate thread - it's already got a nicely centered point and it's already right near the lathe too :2tsup: