Hollow Form Tips Please

[Tim Passmore]

Please give some tips and or resources that will be helpful as I expand my turning----
1. Do you prefer end grain or side grain?
2. Do you prefer to turn wet using the 10% rule and the turn a second time after drying or turn dry blanks?
3. Is cracking more prevalent when turning hollow forms as opposed to bowls?
4. Any specific woods to use or avoid?

Thanks in advance for you expertise.

[Allan Ferguson]

I have used Maple, Walnut, Elm, Box Elder, KOA. Grain orientation depends upon desired shape and appearance. Dry wood is my preference. Cracking with dry wood has not been an issue. Look though the posts. I have turned some pieces with cracks already provided. Allan

[Tim Passmore]

Thanks Allan.

[Scott Hackler]

1. Do you prefer end grain or side grain?

End grain for me, unless it is burn or wet Madrone...then it doesn't matter. Another bonus in the strength of the tenon in end grain orientation.



2. Do you prefer to turn wet using the 10% rule and the turn a second time after drying or turn dry blanks?

I turn all smaller HFs (5" and smaller" to final thickness and let them dry. Although at the 1/4" to 1/8" I hollow to, it is pretty dry by the time I am done. Larger HFs might get rounded again on the outside, but I rarely ever re-hollow.



3. Is cracking more prevalent when turning hollow forms as opposed to bowls?

I don't have very many HF's crack, but again I turn them wet and to final thickness to that helps. I do make the occasional funeral urn and I will re-turn those, just to make the lid fit properly.




4. Any specific woods to use or avoid?

Wet Madrone is awesome to turn, but it will start to distort and warp almost before you get done hollowing it! I like the effect and I would like to get some more of it. Cottonwood has not worked out well for me and warped a lot.

[Dennis Ford]

1. end grain vs side grain? I turn both but much more side grain pieces than end grain.

2. wet, dry I have done twice turned from wet, turned to final thickness from wet and a few from dry wood. Most are turned to final thickness while wet; I like organic character of some distortion.

3. cracking? With a once and done turning; cracking is a problem only if the cracks are pre-existing or the wall thickness is left uneven. Twice turned hollow forms can have cracking problems unless carefully dried.

4. wood selection. Some woods work better for certain styles than others but any wood can be used for a hollow form.

[Tim Passmore]

Thanks Scott and Dennis

[John K Jordan]

Please give some tips and or resources that will be helpful as I expand my turning----


I've watched the other John Jordan turn a few. He has some info on his web site which may be interesting along with a few pictures:
http://www.johnjordanwoodturning.com/John_Jordan_Woodturning/True_To_Form_Cover_thru_22.html
http://www.johnjordanwoodturning.com/John_Jordan_Woodturning/How_to_Create_the_Perfect_Hollow_Form_6-8.html
http://www.johnjordanwoodturning.com/John_Jordan_Woodturning/How_to_Orientate_Wood_for_Maximum_Visual_Impact_6-8.html

John turned them in one go from green to finish cuts. One thing I thought was interesting: after turning he put an air hose in the opening, sealed it a bit with his hand, and much of the remaining free water bubbled out the sides. I suspect that probably sped up drying but might not help with distortion. He turned pretty thin and made it look easy, of course he's had some practice.

Those I've turned personally have been mostly end grain. I like to use eastern red cedar since it is very stable and I have it in large pieces.

JKJ

[Tim Passmore]

Thanks so much John-----those look like great resources and I appreciate your insight.

[Edward Weingarden]

I turn most of my HFs end grain. You get different visual effects due to grain direction if you turn end grain vs face grain. You will also get different effects if you have both heart wood and sap wood in the vessel depending on whether it is mounted end grain vs face grain.

99% of my HFs have been turned wet. I used to turn them all to final thickness in one session. Now I twice-turn some of them. I leave a half inch wall thickness so there's plenty of wall to get it back to round if it distorts significantly. I also re-turn the inside; if I haven't had to take much off of the outer wall, the piece usually feels too heavy so I true the inside and get the wall thickness to 3/16" or 1/4".

Cracking will be a problem if the vessel dries too fast, and/or the wall thickness is uneven. When I turn end grain pieces, I usually have the pith in the center of the piece. I've had very few pieces crack with the pith in the center. When I turn to finished thickness in one session, I may put the piece in a paper bag for a day or two. If I'm doing a twice turned piece, I coat the entire exterior with Anchorseal and let it hang upside down while drying. Even with these precautions, I've had some crack; I guess it's the nature of the business.

I like to turn maple and there's a reasonable amount of ambrosia maple in my area. I've found white oak to be a problem with cracking. Locust is nice but very dense and takes more time to hollow.

I suggest experimenting with different woods, different ways (direction) to mount the wood - end grain vs face grain, all heart wood vs heart wood and sap wood, and anything else that expands your creativity. Good luck, and I look forward to your photos.

[Tim Passmore]

Thanks Edward.

[Tim Passmore]

My first attempts at hollow forms and my first ever posting of pictures. Both are about 6" tall and turned from wet wood. The walnut piece was turned from end grain and the cherry from side grain. I'm anxious to see how they dry.
350920

[Ken Schleman]

I'm impressed Tim, I just started turning hollow forms this week and you seem to be far ahead of me.
Good Job

[Tim Passmore]

Thanks Ken----certainly a work in progress.

[John Keeton]

Nice work, Tim. Particularly the cherry - very nice form. You might consider starting a new thread with the pic. Folks may not visit back to this thread and might miss seeing your work.

[Tim Passmore]

John----thank you for the encouraging words.

[john taliaferro]

Ken , welcome to Sawmill .

[robert baccus]

Very nice work on the hollow forms. Will someone define "hollow forms" vs vases, pots, SW forms ect. please. Confused. (easily)

[Dane Riley]

A hollow form is hollowed thru a small hole as opposed to just drilled.

[John K Jordan]

Very nice work on the hollow forms. Will someone define "hollow forms" vs vases, pots, SW forms ect. please. Confused. (easily)

As Dane said, a hollow form has the inside removed through a small hole, sometimes not much larger than the shaft of the tool. This can be challenging and physically strenuous and stressful when turning a thin wall. People use various things such as big sturdy frames to constrain the torque, and lasers and camera tricks to help "see" the tool location.

A "vase" usually has a wider mouth and is a lot easier to turn unless it is large. Some use glass or plastic inserts to hold water for live flowers.

I generally think of a "pot" as a deep bowl with a wide mouth. Others may have different definitions.

A "weed pot" is a small vessel often used for small dried or fake flowers, usually made by turning the outside then drilling a simple hole to hold a stem or two.

A "box" is usually fairly small, has a lid, often snug fitting. A larger box might also be called a "lidded bowl", especially if it has a bowl-like shape. The Beads of Courage boxes woodturners make for children being treated for cancers can be anything large enough with a lid.

A "form" can be anything.

I'm not sure what "SW" stands for. Seems like I used to know but forgot. South West, Say What, Small/Wide, Sorry Wood?

Someone could write a glossary, however different people sometimes call the same thing by different names. I call all mine "turnings".

JKJ

[robert baccus]

Roger that John--SW as in Southwestern--same as pueblo bowls/vases/pots ect.