Thread: WIP: deep hollowing

I hope this isn't posted too late. Or, maybe you had better luck than I did. Your offset end hole and larger shank may or may not be advantageous.

For my first Oland tool, I used ½" round bar with a 1/8" HSS cutter, centred on the shank. I arranged the hole for the grub screw so that the other side could be used when/if the near side threads became buggered. Tapping after drilling the end hole was an adventure. Apparently, there was enough flex in the shank wall to throw the tap off pitch - Goodbye tap (two actually). I finally got both walls tapped by tapping very very gingerly.

For my next efforts, I'll drill and tap the hole(s) for the grub screw first. For an offset cutter, with only one position for the grub screw, and the end hole drilled first, it might be best to drill the pilot hole, then relieve the far (weaker) side of the hole to clearance diameter, then tap only the near side. This should preserve the tap, as well as some of your sanity.

Joe

Thanks Joe.

The shaft is to take the Proforme head, not an Oland tip, as shown in the first pic above.

But I am thinking about setting up the other end of the shaft to take a removable HSS square cutter. Wondering about grinding a deep flat and fixing a washer with two screws to clamp down on the cutter and allow it some swivel.

Originally Posted by rsser

(Just to keep Scooter's blood pressure down a grub screw was found to hold the spigot this time )

Goodonya Ern

Ern,
Are you wanting o allow the cutter to swivel as you work?
I think if this is the case you will have a huge problem controlling you cut.

Well, 'swivel' as in angle it, clamp it down and go in.

Twisting forces obviously will increase in proportion to the length of tip overhang from the shaft, and the shaft will be held with 4 grub screws in the support, and I dunno whether those will be enough to stop the twisting. Should do.

"...and the shaft will be held with 4 grub screws in the support, and I dunno whether those will be enough to stop the twisting. Should do."

Ern, I only have two grub screws in my captured rig, and it holds well. Sometimes I have a cutter in it with a tip that's over 1.5" from the shaft center.<!-- / message --><!-- sig -->

Originally Posted by OGYT

Ern, I only have two grub screws in my captured rig, and it holds well. Sometimes I have a cutter in it with a tip that's over 1.5" from the shaft center.<!-- / message --><!-- sig -->

I prefer to see 2 grubscrews instead of 4 . With 2 you are clamping against the rounded edge of the hole whereeas 4 grub screws dont jamb it against the wall. i think 2 are stronger and less likely to come loose. Although it is not in the centre which you can adjust 4 to do.

Originally Posted by rsser

Thanks Joe.

The shaft is to take the Proforme head, not an Oland tip, as shown in the first pic above.

But I am thinking about setting up the other end of the shaft to take a removable HSS square cutter. Wondering about grinding a deep flat and fixing a washer with two screws to clamp down on the cutter and allow it some swivel.

Yup. Got that concept, Ern. I was just describing the hazard of tapping across another hole.

Joe

Sorry Joe. Misunderstood you.

K, got some shed time tonight.

Had to drop the shoulder some after yet more filling.

Major voids at the top branch were revealed but luckily I could get an almost unbroken bead at the top ... this will define the opening (pic 1).

That meant reducing the belly. Did this with a 3/8" bowl gouge but I didn't manage too good a job with the tango and had to clean up the line with a scraper. I've never done a curve this long before and clearly need to take dancing lessons to free up the hips ;-}

Didn't seem to make much difference to the finish whether the scraper was at 45 degrees or flat on the rest. It was surprising though how quickly the cypress dulled the burr.

Taking off more timber revealed more checks so plenty of CA and sanding was called for.

I'm now quite happy with the form (pic 2).

Next step is to chuck it. That will throw it out of round a bit but I'll get out the 80 grit gouge for some mucky retruing.

May also run out of grip; if so I'll try F&E's tip to build up the tenon.

(Actually, looking at the pics, maybe the form needs checking; would like the foot to be clearly narrower than the opening.)

I've lost track of which end is up (Nothing new about that of course ). Don't make the foot so small that it tips over easily. Or maybe just glue some lead shot in the inside bottom as needed for ballast.

Joe

Good point Joe. But this is art ;-}

That said, I may not be able to hollow to the base so it'll bring it's own weight

(Added: the right side is up.)

And thanks Al and Calm for the grub screw tips.

So to continue the saga ...

Got back out tonight and sized it up for the chuck.

Enough tenon for grip (hooray) but too much length (doh again).

So I remounted it between drive spur and cup centre, took out most of the excess length and removed the piece and cut the stub off with a saw.

Remounted it lightly in the chuck, brought up the tailstock and pushed it square into the jaws. (For any newbs, that's why you leave a shoulder on the tenon.).

The nice thing about a cup tailstock centre is that it'll take these remountings and still register positively.

This has turned into a great tutorial fellas!!!

The foot looks about right to me if you stand it up the right way.