can I turn a green platter?

[Tom Gardner]

Howdy, New turner here. I have some fresh elm that I'm playing with and I've turned a few green wood bowls for secondary turning. Can I do the same with platters? Keep the thickness about 1:10 to the diameter?
TIA, Tom

 

[odie]

Howdy, New turner here. I have some fresh elm that I'm playing with and I've turned a few green wood bowls for secondary turning. Can I do the same with platters? Keep the thickness about 1:10 to the diameter?
TIA, Tom

There's only one way to find out! I wouldn't hesitate to give it a try.......

It depends on moisture content, species.....and, the individual piece of wood. Some will warp more than others, even if everything else is the same. I can't recall specifically if I've done an Elm platter, but I'd probably be more inclined to remember if it wasn't successful.

I've turned wet Elm bowls, and a number of wet woods of various species into platters, but I don't think I've made any platters with a high MC.....all I've done are somewhere in the mid twenties (or lower) percent IIRC.

ooc

 

[john lucas]

You can but they are much more likely to split on the end grain. I have been saving platter blanks for the last few years to see how that works I don't turn them first i just cut the blank and seal the ends with wax. The closer you get to the pith the more they warp and the more likely to split so the best bet is start with big logs and cut them several inches from the pith.
Well the best thing would be to make quarter sawn blanks but I doubt anyone has t any of us have logs that size
The reason I say just rough cut them instead of rough turn them is its hard to predict how much warp and how even it will be. If you leave it rough you can mount it between centers a d readjust it so the top face will be as true as you can get it and then you can turn the backside

 

[Dale Miner]

Part of the criteria for the thickness of the roughout is the location in the log the blank is cut from. A pure quater sawn blank will have very little tendency to warp and will only go oval. Of course, this would require a large diameter log since avoiding the pith means that the blank would need to be cut from half the diameter of the log. In a typical cutting of a log for a platter blank, the log is split about an inch away from the pith and the blank cut from the half log (without the pith). This results in a blank that is nearly quater sawn and will have only a slight tendency to warp during drying. The piece will still go oval during drying. If the blank is cut in this fashion from a very large log, the warping will be less than if cut from a smaller log. The farther away from the center of the log the blank is cut from, the more warping will occurr.

Warping occurs during drying as a result of the difference in the shrinkage rates between the tangential and radial shrinkages. By cutting the blanks as near the center of the log as possible, and from larger logs, the blanks will have less wood imparting tangential shrinkage and a higher percentage of wood with radial shrinkage. By having only one mode of shrinkage, warping is lessened. The piece will still become oval during drying however, and allowances for details to be maintained in the second turning are needed.

When cutting platter blanks as above, or from crotch sections, I generally do not leave the rough out at ten percent but some where around seven percent. An 18" rough out at 1.5" is thick enough. If the blank is cut from farther away from the log center, ten percent may not be thick enough.

 

[hockenbery]

John and Dale covered it well.

Success in drying bowls goes way up when the bowls have nice curve so the wood can move.
A platter is a shallow flat bowl with little curve and more prone to crack in the double turn drying process.

Drying a platter blank board and cutting platters from it works well.
And if you have a large log green turning the quarter sawn
I cut platter blank slabs 2" thick from logs about 3 feet long seal the ends and dry them on a shelf for a couple of years.
I can then center the grain on the center of the tree and get nice rings in the center of the platter (bark side up) or the hyperbola grains
Put stickers between the slabs to Allow air circulation.

You can turn a thin platter less than 1/4" thickness green with great success.
A lot of folks turn these as squared or rectangles with the bark on or off.
A 1/4" thick can be a functional piece.
thinner than an 1/8 they warp more and become exceptional display pieces as well as confirmation that your skill level is fairly advanced.

 

[hockenbery]

Just saw you were from Denver,

If you were at the RockyMountain Symposium and saw the Rudy Lopez demos, that is the kind of green turning that works for thin platters.

Al

 

[Tom Gardner]

I was there! It was great!

I went to Rudy Lopez's talks on natural edge winged bowls and thin stem natural edge goblets. Also Tom Wirsing's presentation on platters as well as his hands on, but I forgot to ask about green wood. And some of David Ellsworth's talks too.

The remaining elm log is about a 16" diameter crotch. I will cut it about 1" from the pith on each side and try a bowl from one side (maybe natural edge) and a platter on the other and seal the ends. Should I seal just the end grain or the whole kit and kaboodle?

Just started woodturning in the last year and have joined the Rocky Mountain Wood Turners club.

Thanks all, Tom

 

[hockenbery]

I was there! It was great! I went to Rudy Lopez's talks on natural edge winged bowls and thin stem natural edge goblets. Also Tom Wirsing's presentation on platters as well as his hands on, but I forgot to ask about green wood. And some of David Ellsworth's talks too. The remaining elm log is about a 16" diameter crotch. I will cut it about 1" from the pith on each side and try a bowl from one side (maybe natural edge) and a platter on the other and seal the ends. Should I seal just the end grain or the whole kit and kaboodle? Just started woodturning in the last year and have joined the Rocky Mountain Wood Turners club. Thanks all, Tom

Think about Rudy's winged bowl with just the wings then you have a thin platter.
This is an excellent way to show off the crotch figure.
It is a challenging endeavor but well worth the effort.

Rudy is working with wet wood, Tom is working with dry wood.

The crotch poses a couple of options.
I either cut a crotch dead center on the piths or 3/4" to one side of the piths.
With dead center I get two blanks that's show the most flame and each one has a "Y" shape pith less the chain saw kerf.
If I turn a bowl with the flame in the bottom, the best flame is on the outside of the bowl and some flame is lost in the chuck tenon.
With the cut 3/4 " off the pith I get one blank with all the feather and using a chuck mount I can get the inside bottom of the bowl a little below the center and have a lot more flame than bowls from the blanks cut dead center on the piths. The other piece probably won't have much flame.
These options yield either two good bowls or one great bowl.

The feather or flame figure is widest at the pith of the main stem leading up between the piths of the two branches.
The flame figure is not real thick and you will lose a lot ( maybe all) of the flame if you cut an inch from pith.
have seen a big box Elder crotch that showed flame at 4" from center but that is really unusual.

Below is NE bowl I cut at the pith. You can see the pith in the bowl and cracks were in the pith when I cut the blank.
It won't hold soup but it will hold 3dozen apple and a hand of bananas.

Sealing: a crotch platter blank I seal the endgrain and the face along the pith area. These place want to move so slowing the moving helps. I also plan on cutting 2" off both ends of the blank when I turn the platter to get rid of any end checking. The feather sometimes gets some tiny checks but thew can be left as a feature or filled.

If I'm cutting a crotch blank to dry for a platter, I seal the end grain, the crotch figure and the pith area.
With the crotch you have wood moving in at least 3 directions so slowing the drying is extra important.

I got to see Lee Carter's demo in July. The Rocky Mountain club has an amazing amount of talent, they will teach you a lot.
Have fun

Al

 

[Tom Gardner]

Well, the first half turned into a bowl.

 

[robo hippy]

For green platters in the more traditional style, probably most important to have the bottom of the platter towards the pith, and the top to the bark. This is the same orientation that you would use for a natural edge bowl. Main reason for this is the edges will warp up as it dries. No problem with this orientation. If you have it so the bark side is the bottom, and the pith the center, then the edges warp down, leaving you with a platter that has a high center so every thing rolls off the edges. Took me a while to figure this one out.

robo hippy