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Yet another ball turner----
- Thread starter woodcutter
- Start date
- Joined
- Feb 12, 2013
- Messages
- 17
Not to be stupid but I see how it shapes the back end of the ball , but I'm missing how it does the front or top as you will. I see that it cuts concave but I'm not understanding the convex
I started out with a piece of Durabar from Speedy Metals.Not having a power hacksaaw, got a bit of a work-out. Actually not that daunting, about 15 minutes using a new, high quality, 14tpi blade.
Squared up and sized the piece on the Bridgeport. This will be the base.
The top half of the turner pivots on the base plate and is held in place by a conical nut which allows for sweet motion with no slop.Bored the baseplate on the lathe and then turned the bevel. Also turned the conical nut without moving the compound so both would be exactly the same, somewhere around 45 deg.
I had an oddball size tap, 15/16 - 16. Used that to thread the nut and the swivelling plate and cut a stud on the lathe to match.
The swivel plate, also made of durabar has a dovetail slot which carries the toolholder. Did the same sizing and squaring routine and here's a couple of shots milling the dovetail.
Drilling for the gib adjusting screws.
For a previous project I made a clamping fixture to hold the gib in place to mill the bevels and dimples to receive the adjusting screws.
The toolholder has a mating dovetail and here it's being cut to shape.
The tool is a standard 1/2 x 1/2 lathe tool with a triangular insert, all held down by a cap with four 1/4- 20 nuts.
I had to cut away the corners of the swivel plate so it would clear the mounting bolts that hold everything the the cross slide. Did that with a little 6 inch rotab on the Bridgeport. A few light cuts and it worked fine.
I found that when I assembled it, the conical nut would either loosen or tighten when I swivelled it so I drilled and tapped for a setscrew to hold the adjustment. A slug of solder under the setscrew keeps the threads on the stud from getting mangled. I had already Locktited the stud into the swivel plate so I had to hold the whole thing in the fancy vise I got at an estate sale. First time I've used it.
Here are all the pieces before assembly.
Here it is in action.
It cuts smoothly with very little effort required to move the handle. By adjusting the the position of the cutter with respect to the pivot point it will cut either concave or convex. There is 3/4" clearance beneath the cutter so the max diameter ball it will cut is 1 1/2". Hope you enjoyed the slide show. Henry[/QUOTE]
I started out with a piece of Durabar from Speedy Metals.Not having a power hacksaaw, got a bit of a work-out. Actually not that daunting, about 15 minutes using a new, high quality, 14tpi blade.
Squared up and sized the piece on the Bridgeport. This will be the base.
The top half of the turner pivots on the base plate and is held in place by a conical nut which allows for sweet motion with no slop.Bored the baseplate on the lathe and then turned the bevel. Also turned the conical nut without moving the compound so both would be exactly the same, somewhere around 45 deg.
I had an oddball size tap, 15/16 - 16. Used that to thread the nut and the swivelling plate and cut a stud on the lathe to match.
The swivel plate, also made of durabar has a dovetail slot which carries the toolholder. Did the same sizing and squaring routine and here's a couple of shots milling the dovetail.
Drilling for the gib adjusting screws.
For a previous project I made a clamping fixture to hold the gib in place to mill the bevels and dimples to receive the adjusting screws.
The toolholder has a mating dovetail and here it's being cut to shape.
The tool is a standard 1/2 x 1/2 lathe tool with a triangular insert, all held down by a cap with four 1/4- 20 nuts.
I had to cut away the corners of the swivel plate so it would clear the mounting bolts that hold everything the the cross slide. Did that with a little 6 inch rotab on the Bridgeport. A few light cuts and it worked fine.
I found that when I assembled it, the conical nut would either loosen or tighten when I swivelled it so I drilled and tapped for a setscrew to hold the adjustment. A slug of solder under the setscrew keeps the threads on the stud from getting mangled. I had already Locktited the stud into the swivel plate so I had to hold the whole thing in the fancy vise I got at an estate sale. First time I've used it.
Here are all the pieces before assembly.
Here it is in action.
It cuts smoothly with very little effort required to move the handle. By adjusting the the position of the cutter with respect to the pivot point it will cut either concave or convex. There is 3/4" clearance beneath the cutter so the max diameter ball it will cut is 1 1/2". Hope you enjoyed the slide show. Henry[/QUOTE]
- Joined
- Jan 31, 2014
- Messages
- 2
Depends on position of cutting point in relation to pivot point. If cutter is in front of the pivot point it makes a concave profile and if its behind the pivot it makes convex profile.
**EDIT: Apparently that was already explained, sorry. :banghead:
- Joined
- Sep 4, 2013
- Messages
- 18
Very Nice...On my list as well
- Joined
- Feb 12, 2013
- Messages
- 17
Yes I see now ! wasn't thinking clearly , thanks for replying . Didn't see any other explanation !