# Questions about vases (Hollow forms)



## cabomhn (Jul 22, 2012)

Well school is almost back in session and I am trying to figure out some of the projects I would like to start once I am back at the woodshop.

I think my goal for this semester would be to work toward something like this..

http://woodbarter.com/showthread.php?tid=661

Probably too overly ambitious, but I prefer wild goals and not meeting them than settling for lesser ones. Anyway, during this last semester I pretty much restricted myself to bowls and vases where no hollowing was needed. This semester I have a little more time and want to start expanding a little. 

I was hoping to get some information about turning hollow forms, as well as a good hollowing tool you guys would recommend. I really like the look when things are turned pith to pith, but I know that you have to worry about cracking quite a bit. What woods and techniques do people usually use when hollowing forming vases and objects through the piths. Thanks guys, I appreciate any and all advice!

- Matt


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## DKMD (Jul 22, 2012)

Lots of opinions and ways to get to your end result, but I'll throw in my two bits...

I'd start with an oland style tool that you make yourself. One straight cutter, one at 45 degrees, and a scraper tip will give you a ton of options when it comes to forms. Here's a little article on making your own: http://woodturnersamerica.com/index.php?option=com_content&view=category&layout=blog&id=39&Itemid=109. You can play around on open bowl forms with these tools to help you get the feel... That's important since you can't actually see the cutter when hollowing. Start with shorter forms and wider openings, and clear out the chips often while hollowing. I generally drill a central depth hole before I start hollowing since it makes the cutting easier and allows you to know where the bottom of the inside should stop.

There are a ton of videos on YouTube about hollowforms as well as a bunch of DVDs. This website has a bunch of written tutorials for woodturning projects: http://www.woodturningonline.com/Turning/Turning_projects.php?catid=43

Good luck and let me know if I can help.


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## cabomhn (Jul 22, 2012)

Thanks for the reply! Looking through the different articles and such now. :morning2:


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## Mike Mills (Jul 22, 2012)

I have one like this and like it a lot. http://www.amazon.com/Robert-Sorby-H0506-Multi-Tip-Hollowing/dp/B0000DD14V

You can go to movie clips here http://www.robert-sorby.co.uk/movie-clips.htm#mtht

With the swivel tip it will reach pretty well; given an 1.5" or so opening.


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## woodtickgreg (Jul 22, 2012)

I'm all for making your own tools. The beauty of it is that if you make them with cold rolled steel and don't like something about the tool you can just make another one with what you have learned. You could also have the tool heat treated or do it yourself to give the tool a little more rigidity. Not to hard though so it isn't prone to shatter or break. You can make a bunch of tools for cheap rather than a few tools for hundreds of dollars, if you have the skills to work metal. If you don't have the skills to work metal, learn it! You will use the skill all your life.


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## cabomhn (Jul 22, 2012)

Thanks for the helpful replies all of you! I would love to learn how to do some metal working, but for now I can only work with the stuff I have at school. I will do a little more research but will hopefully be in business soon!


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## Dennis Ford (Jul 22, 2012)

You got some good advise on tooling but not much about endgrain hollow forms. RBACCUS has done lots of endgrain forms and has a good success rate of avoiding cracks. He roughs the form out and drys the rough-out SLOWLY using bags, sealers and I suspect some magic.

I mostly do sidegrain forms but have done a few endgrain. My most successful method has been to rough the form out and drill the pith out completely through the bottom. After the rough-out is dry, I remount it and plug the hole before finish turning.


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## Vern Tator (Jul 23, 2012)

I'm not too fussy about where the grain goes in a hollow form, side grain, endgrain, diagonal grain, it matters not to me. I sometimes turn green to finish and sometimes dry and re-turn. On the dry and re-turn I look at the grain to see which way it is going to move and make sure I allow enough thickness DAMHIKT. (my wife has a funnel area in her garden) I rarely include the pith, because it will only bite you in the butt when you have no other way out. I have had the best success with the pith in, green to finish, end grain, making sure it falls in the foot and then boring a 1 1/4" hole and plugging it with material from the dovetail used in the chuck. Experience does not come from reading, it comes from making mistakes, and after nearly 50 years of turning, there is still a long line of mistakes headed my way. :rotflmao3::rotflmao3:


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## TimR (Jul 24, 2012)

Great advice so far...and lots to digest.
I'll add this on endgrain pith centered turning...but really is best when rough turning is used, though on some final turning it will work as well too.

When I rough turn, I try to keep my thicknesses fairly consistent. This helps avoid differential rates of drying, which leads to cracking.

While turning, especially if green, I'll keep misting the opening and upper part of form to keep from drying out too readily also.

Assuming I have a tenon on the base with pith running through it, I'll use a hose clamp after turning and tighten it every day till it no longer will tighten anymore. I sometimes do this on larger openings as well if cracking is a concern and I have a feature that I can clamp onto.

I slather on shellac or lacquer to the outside of vessel to help dry from inside out, which helps keep the outside of form in compression and not develop cracks as readily.

After a couple months, I'll come back to it and recenter it to clean up the tenon and take to final thickness.


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## cabomhn (Jul 24, 2012)

TimR said:


> Great advice so far...and lots to digest.
> I'll add this on endgrain pith centered turning...but really is best when rough turning is used, though on some final turning it will work as well too.
> 
> When I rough turn, I try to keep my thicknesses fairly consistent. This helps avoid differential rates of drying, which leads to cracking.
> ...



So you are essentially using the hose clamp on the tenon with the pith as a way to control cracking while drying?


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## TimR (Jul 24, 2012)

cabomhn said:


> TimR said:
> 
> 
> > Great advice so far...and lots to digest.
> ...


 Yup! Important thing is to keep tightening especially the first week or two when most drying/shrinkage is occurring, and to strive for very consistent thicknesses, especially at the base. It's tougher to do this at the base, but your odds for success will increase if you have less variation in thickness. Also...I don't think I mentioned, if you'll be turning away the tenon anyway...slather the bottom of the tenon with the pith in it with some endgrain sealer to really slow down drying from the outside. Let as much drying happen from inside out, as mentioned.


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## Vern Tator (Jul 24, 2012)

I think I disagree with Tim, " He who dies with the most wood is still DEAD!" So maybe "he who lives with the most wood wins. " :rotflmao3::rotflmao3::rotflmao3:


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