How do I hollow this out?

[Raif Harik]

Hi, I have this piece. I seem to always end up making this design. I think I may be broken, but that's a different storty.
I'm wondering how I'm supposed to hollow out the inside of the bulb part at the bottom. I've managed to do it with the bowl gouge and with the scraper it but it's hell. I know there are all sorts of hollowing jigs etc, but this is not really a "hollow vessel" this is just a "bowl" that kind of changes direction. Perhaps I do need a a hollow vessel apparatus, but it seems like I'm pretty close with regular tools. I have seen a HSS teardrop scrapper .... thing, that attaches to a flat part at the end of a round bar. Is this what one would use?
Thanks,
Raif

 

[Tim Connell]

I would use a swan neck hollowing tool. Either HSS or carbide depending on your preference. Amazon link for pictures only, no idea if any of the tools listed are decent or not.
https://www.amazon.com/s?k=Swan+neck+hollowing+tool&ref=nb_sb_noss_2

 

[hockenbery]

Lots of options depending on skills and available tools.

A scraper or a hunter tool would do the job. However the distance over the tool rest makes it challenging.
Very light cuts take your time. If the diameter allows I would start with my 3/8” diameter Gouge with a Michelson grind. Looks like it could do the job nicely of the undercut you have but a smallish diameter might cause the rim to hit the handle Preventing the undercut.

a bent hollowing tool like this Bosch tool or an Ellsworth style tool would be easier to control. Could be used Hand held or with a Jamieson or other system.
The surface then needs to be smoothed.
A scraper tipped hollowing tool like the Bosch scraper or a hunter tool would do nicely
Or an 80 grit sanding ball. A small piec you could remove all the wood with the Bosch scraper.

This shows how a hunter tool could be used on the curve.

 

[Dennis J Gooding]

What is the max hollowing depth?

 

[hockenbery]

I seem to always end up making this design. I think I may be broken, but that's a different storty.
I'm wondering how I'm supposed

That is a great design to explore...
Your piece is like some I have done. Flared rim and a wider vessel. You get different looks depending on the relative heights of the rim and vessel and how you transition from the rim into the vessel. Play with these to see the effect and what looks best.

this is a small Face grain maple hollow form maybe 8” tall.
Same basic design as yours but I set the rim higher and use a curve to transition into the vessel.

 

[John Tisdale]

Raif,
Hats off to you for being able to do this with a bowl gouge. And hats off to the guys that can do it with a swan-neck hollowing system. I ain't that good and have no interest in mastering the advanced techniques required.
Instead of boring the forum with minutiae, come on up - it's a three hour drive to Dallas - my email is john.tisdale@yahoo.com. While I can't extend normal hospitality in this covid-19 world, I can show you a couple of thing in an hour or so that will redirect your efforts. Cost of lesson: free. Cost of Rolle Munro-II: over $200. Cost of toolrest: between free and $400. design is free - maybe you have a brother-in-law or best-bud machinist.
A STORY:
A guy called me six or seven years ago that he had seen my work and had been searching me out. I invited him over one Saturday to show him what I do and how I do it. He came over during a week-day ready to go to work. At the time, I was hollowing a 20" dia maple (similar to the one in my avatar). We had gotten to about 10" inside diameter and my wife reminded me we need to do the Meals on Wheels delivery - I excused myself and told him to keep going.
Got back in a bit over 1-1/2-hours - he had easily hollowed another inch or so with zero catches or anxious moments. The cool part of the story is: he had never turned and never held a gouge. A cooler part of the story is his hollow-forms are going for the big-bucks in a top gallery.

The moral of the story is: if it looks hard, it probably is. There may be an easy way with fewer opportunities for error

 

[robo hippy]

If you plan out the design first, you may be able to do it all with standard tools, which would mean a drawing and laying out angles you can reach with the tools you have. The problem I have with that approach is that the design starts out as one idea, and some times it stays that way, and other times the wood determines another design. You may need to get another new toy or 5... that is a nice design, I would call it a 'closed' form as there is part of it where the opening is smaller than the maximum diameter.

robo hippy