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Jim Morgans Wood Profits

Jim Morgan's Wood Profits

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By Steve Blenk

White most woodworkers are taught to avoid using green (unseasoned) wood, woodturners can grab a block right off the stump and go to town making shavings. Here are some tips to make green woodturning fun and to ensure that you get the best results from your experiments.

Freshly cut (green) wood with a high moisture content is, by nature, unstable. As it dries, it is prone to warp, check and generally do things that give woodworkers nightmares. The movement is caused by the cells of the wood changing shape (shrinking) as the moisture leaves. Outer layers often dry faster than the inner ones. This uneven drying creates stresses in the wood, which cause checking. Left to itself, drying is a slow process, with thicker air-dried material often requiring years of seasoning. We kiln dry (KD) most lumber these days and, while this speeds the process, it can result in another set of problems. Wood can be "case hardened" (hard and dry outside, still wet inside), checked or fractured with "honeycomb cracks" (checking not visible from the outside). It can also be over-kilned to the point it becomes prone to fracture with hidden stresses. The thicker the material, the less effective kiln drying generally becomes. KD wood is no fun to turn, either. It is hard on both the turner and the tools.

There are two ways to approach green woodturning. You can look at it as a step designed to speed the drying of bowl blanks to a fin-ishable form, or you can sculpt complete turnings in the green condition and let nature have her way. You can even give her a prod, as you will see.

Mount a 10" segment of tree limb or trunk between centers. Mount it off-center to avoid making the weaker pith part of your stem Remember to raise a round nub to grab later in a chuck. Hidden knots or defects can create a problem as you turn.
High Pressure Accidents

Beautiful, natural edged goblets are a great first project if you are interested in trying green turning.

With the stem and the bowl of the goblet shaped, you can remove the live center (and its padding that prevented scratches). This goblet is almost ready to be parted from the remaining piece of limb.

Beautiful, natural edged goblets are a great first project if you are interested in trying green turning.

With the stem and the bowl of the goblet shaped, you can remove the live center (and its padding that prevented scratches). This goblet is almost ready to be parted from the remaining piece of limb.

First Project: Try Turning A Goblet

A good beginning project for finished green turning is a naturals dge goblet turned from end grain. Select a fairly straight branch section about 3" to 4" in diameter and about 10" long. Fruitwoods like cherry or apple for this work well, but any reasonably hard wood will also do the trick. Mount it between centers with the pith (center wood) mounted off-center so it will not be included in your goblet stem. Turn one end round so you can grab it later with a chuck, and lay out your goblet sections {i.e., rim, stem, base). Leave the bark at the upper edge of the rim area intact. You will quickly discover that green wood turns like butter, giving you wonderful long shavings as you cut. Keep your edges sharp, and try to keep your cuts even. Get as smooth a surface as you can manage now, as the wood will dry to show your tooling marks later.

Switch to a chuck mounting, and begin to hollow your goblet. By working carefully you can produce a very thin wall. This has two advantages. First, it will allow you to use a light to see your wall thickness, as the wet wood is translucent (see photo, next page). Second, by removing most of the wood you will eliminate drying problems, as the remaining material will be much less likely to check or crack. Finish cutting and sanding the whole cup area before moving on to the stem, as it will quickly begin to move out of round. Sand with 120-grit paper, and don't be surprised at how fast it loads up. The heat produced by sanding will begin to dry the surface, and you will then be able to get it fairly smooth with Gner papers.

Once your cup is done, move your live center into position to support the turning. You will need to pack some soft material like a rag or foam rubber into the cup to keep the center point from damaging the bottom (see top left photo). Now use a small, sharp gouge to turn the stem and base, in that order. Sand the stem carefully! The thin green section will simply twist off if you create too much torque force. This is why you excluded the weaker pith wood in your setup. Finally, cut your base away from beneath, and part the goblet off. As with the cup, try to get the base as thin as you can to prevent checking.

The Gentle Prod...

You can now either leave the drying process to nature, or you can get creative and pop your goblet into the microwave. (Warning: using the kitchen microwave for this trick is considered grounds for divorce in some states!) Thirty seconds to a minute or so on "high" can produce some startling results, as the thin wood will bend and warp as it heats and quickly loses its remaining moisture. Don't over-do it, as the wood will crack or even begin to smoke and produce a very evil smell almost guaranteed to disturb domestic tranquility! Start with a short time. You might consider submerging the goblet in Danish oil or similar finish to stabilize it after micro waving.

You can also use this same set of techniques for making small open bowl forms, both end grain and flat grain. Thinner is almost always better, as the wood can move without checking. Experiment with grain alignment for differing results, and rig a bright light by your lathe to help judge wall thickness. A spray bottle of water can also be helpful to slow down deformation while turning.

Green Bowls in the Rough

Rough-turning green bowl blanks is a simple process: just mount your material as you would any bowl, and remove the waste down to about 1" to l'/á" of thickness of the eventual finished bow]. Be aware that larger blanks may actually spray water as you centrifuge' them! Leave a stub tenon 011 the foot end of each to allow a quick grab with a chuck for remounting to true the rim. then seal the blank with wax or liquid end-grain wood sealer and toss it on a shelf for six months or so in a fairly warm dry place. You should expect to lose some blanks to checking, but you will have cut your drying time by years and will have many more blanks to work with sooner. If you had air dried the blanks you would lose a comparable number. Also, removing green wood from a blank is much easier and faster than turning dry wood. You will be able to rough out a large number of bowls quickly with little effort in green form. After sufficient drying time, (which varies, and will require some experimentation on your part) just remount the rough blank and turn it down to final form.

Some turners have specialized green turning to a high form, using polyethylene glycol (PEG) in solution to treat finished green bowls. The Molthroups — Ed and Phil — are masters. They have achieved remarkable results, especially with very large pieces. Just remember, if you use PEG you must finish with a polyurethane varnish, as nothing else will stick to the wood's surface.

If you get hooked on green turning, try reading Michael O'Donnell's book on the subject. He discusses every aspect from harvest and blank alignment to finishing. Have fun with your projects as you "go green!" @ _/

The water-saturated wood transmits light quite well. You can use this fact to help judge the thickness of your goblet wails.

The water-saturated wood transmits light quite well. You can use this fact to help judge the thickness of your goblet wails.

Can You Turn Green Wood
Green turning creates piles and piles of shavings. But be careful: they are wet and can rust your tools and encourage mold growth. Quick cleanup is an essential task when turning green wood.

A Heads-up On Turning Green

Green shavings are WET and will rust your equipment very quickly, so clean up after each session. Green shavings will also encourage the growth of molds and other nasty fungi in your shop, so get them out to the trash or compost pile before the mushrooms show up. Green turnings, especially thin ones, distort with surprising speed, so don't expect to start one today and finish it tomorrow: do it all in one session. If you must take a break, cover the turning with a plastic bag to seal it.

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Wood Working 101

Wood Working 101

Have you ever wanted to begin woodworking at home? Woodworking can be a fun, yet dangerous experience if not performed properly. In The Art of Woodworking Beginners Guide, we will show you how to choose everything from saws to hand tools and how to use them properly to avoid ending up in the ER.

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