Discussion before the meeting concerned offset or eccentric turning:
One member uses an Australian Vermec multi-center chuck (https://www.vermec.com/store/p78/Multi_Centre_Chuck_Deluxe.html) to help with different angles.
One member mentioned a demo by Barbara Dill on offset turning. https://vimeo.com/156359602
The caution was given that a turner has to be cautious when doing offset turning to not lose control of the project. Due to a light and heavy side of the piece, it can go airborne making it a safety issue.
One member turns his projects between safety centers, making it safer. He uses the safety center to start 90% of his bowls also. Robust is one source of those centers http://www.turnrobust.com/product/live-center/. Several members weren’t sure what a safety center looked like. It was described as a center with a point and a solid ring for a friction hold on the wood. It has a set screw that can be adjusted to set the distance from the wood to the point. It doesn’t spin so it can be used as a drive center on the headstock. We saw examples of a safety center, a Stebcentre and a spur center to contrast their differences and discussed how they work differently with wood.
Topic: Toxicity and Allergies
- https://www.wood-database.com/wood-articles/wood-allergies-and-toxicity/ is a valuable source of information on types of woods, their allergic qualities and toxicity. We decided mulga is definitely to be avoided!
- Members’ comments about types of wood: Juniper can cause contact dermatitis; Turning olive wood can cause a need for Italian food; Cocobolo affects many people; Silky oak, found in Phoenix, is a beautiful warm weather wood but one member knew someone who’d been hospitalized due to a reaction to it; Alligator juniper is high in toxins and many people have a problem with it; Juniper, cedar and mesquite have been excluded from use at the Yavapai College woodshop in the past due to allergies; Ironwood is very hard to turn unless it’s still green–otherwise it requires very sharp tools and patience; Osage orange is beautiful and doesn’t crack but can be irritating; Purpleheart has a fine dust to cause breathing difficulties without a mask; Bloodwood is also very dusty and will bleed onto other adjacent woods such as maple.
- Long sleeved t-shirts (that don’t get caught on the lathe) can protect the skin and respirators protect the lungs.
- Identifying found wood is difficult; if the wood is unknown, the level of toxicity may also be unknown. Wood types also have different names.
- Many imported woods from the UK, Australia and Africa grow well in the warmth of Phoenix.
- Each person reacts differently. Some people don’t react at all to woods, or have built up a resistance or immunity due to repeated exposure. Others become more allergic as they are exposed to certain woods. Awareness to your own reaction is important.
- Washing not only hands, but also arms, after turning helps reduce dermatitis reactions.
- Wood toxicity is greatly reduced by sealing the wood with varnish, poly or other finishes after turning. Completely curing a piece (about 30 days) may eliminate the allergy issue since the proteins that cause the allergy dissipate over time.
- Creams and Benadryl can help with contact dermatitis. Benadryl is available in a lotion or a pill form. The question was asked: If an aspirin helps in the case of a heart attack, could giving Benadryl help if someone is in anaphylactic shock or having breathing difficulties? There are downsides to Benadryl and calling 911 immediately for advice is the best course of action. Some people with known allergies that relate to the respiratory system may keep an epi-pen in the shop as a precaution.
- Barrier creams or salves applied topically seal the pores of the skin to protect it.
- Local honey from the Prescott area, taken daily, helps build resistance to local pollens. (Honeyman is one source.)
- Splinters can be dangerous! Any wood can cause toxicity and splinters should be removed immediately. Hydrogen peroxide should be kept in the shop for cleaning the area after removing the splinter. If not removed, the toxins can dissolve, enter the bloodstream and may cause sepsis which can be a life-threatening infection. With sepsis, every organ in the body can be affected and it takes a long time to recover. For more information, search for ‘splinters and sepsis’ on Dr. Google.
Topic: Difficulties with wood and tips for turning
- Cracks in wood are discussed at each meeting, but there are different members attending or new ideas presented. Revisiting ideas helps since they make sense differently at different times. Safety when turning is the most important factor. Taping the outside of a project can hold it together while turning the inside. CA works best on smaller cracks. Epoxy or resin are used for more structural reasons. Epoxy should be considered when the crack is 1/8” or larger. When seeing a crack, sometimes it’s helpful to watch and see if it will grow or how it changes, adjusting turning as needed.
- Different pieces of the same type of wood may be different. Examples: an apple project treated with pentacryl broke apart; another project with apple had few cracks. A project made with elm was very rough and splintery; another piece turned nicely. The same species that was grown in different environments also turn differently.
- A slurry with TiteBond wood glue and sawdust makes a very strong filler that is stronger than the wood itself. The slurry should be thick but looser than a paste. Pack it tightly and add a drop of water to help the glue permeate through the sawdust. Dry thoroughly before sanding. Certain finishes may not work well with this technique. The thicker the glue, the longer it takes to dry.
- A Project Farm YouTube video shows testing and comparison of wood glues (https://www.youtube.com/watch?v=k-g3efGa3sI).
- Starbond is still the favored brand of CA. Five-minute epoxy is actually a 3-minute epoxy.
- Black CA may have tiny bubbles in it and using a heat gun can draw out those bubbles.
- Members have had problems with CA floating on the surface or bridging across the top rather than penetrating through things like copper powder. We reviewed the idea of layering and using a scalpel to cut through and blend the layers.
- Aspen is one of the woods with a lot of tear out and fuzzy fibers. Sanding sealer, thinned shellac, etc. will seal the fibers then use sharp tools to turn it.
- Sawdust can be moved with a leaf blower, but it may not be the best idea.
- The problem with using colored pencils in projects is that the wax-based leads smear and are messy. An alternative suggested was Bic Xtra-Fun pencils with graphite and colored wooden barrels. They look like colored pencils when embedded in resin and avoid the issues seen with wax leads. (Amazon carries these.)
- The power of demos is that we can learn things we shouldn’t do. If someone says, ‘Trust me,’ they are sharing their experience with problems.
- There are two types of resins: polyester resin (which is usually combined with only a few drops of hardener added to a larger quantity of resin) has a horrendous odor while urethanes (which are usually mixed one to one) have no odor. The longer a resin cures, the less odor there will be.
- There were questions about using walnut oil for sanding and as the final finish. Curing it reduces or eliminates the allergy issue. It’s self-hardening and, as with all finishes, is food safe after it is cured. According to Mike Mahoney’s site, once it’s cured it’s stable.