Another Hollowing Tool Question

[Shaun Tyler]

Are there any recommendations for how deep a particular tool can safely go? Stuart Batty has some recommended ratios of overhang vs handle lengths but as far as I’ve found he doesn’t mention hollowing tools. I just finished my second hollowing project and it was definitely pushing things so I have some empirical data ;-) But it would be nice to go into future attempts with better planning.

 

[Dave Landers]

It's more about bar size/diameter than the handle. Trent Bosch has some recommendations on his site, on the FAQ page:

The 1/2” Hollowing tools can hollow approximately 6” deep. The 5/8” Hollowing tools can hollow approximately 8” deep, the 3/4” Hollowing tools can hollow approximately 12” deep and the 1″ Hollowing tools can hollow approximately 14″ deep.

Your mileage may vary depending on mainly experience and aggressiveness of your cuts. Be gentle and take small cuts and you can push these a bit. Be aggressive and you'll not get close to that deep.

 

[hockenbery]

Are there any recommendations for how deep a particular tool can safely go?

Safely is 99% on your skill level and hollowing method.
You can get a catastrophic catch a 1/4” deep.

If you want to know about hollowing effectively - the working overhang distance is depends on the bar diameter, skill, and hollowing method.

A 3/16 hollowing bar works great ornament balls 4” overhang. Longer overhang the bar vibrates too much to be effective.
Lighter cuts can compensate but eventually you get to a depth where the cut has to be so light that you are barely removing any material.

What I do for general depth guidelines for myself
1/2” bar 7” deep
3/4” bar 9” deep
1.5” bar 18” deep. - I’ve not done anything deeper.

I could maybe hollow 12” deep with a 3/4” bar but it might take an hour to go the last 3” that i can hollow in 5-10 minutes with my 1.5” bar ( chip removal can take more time than cutting at depth)