The overlying question was: How to repair cracks and/or is the wood safe to turn? It was helpful for members to bring examples of projects/cracked wood and bowls to show during the discussion as topics evolved.
Spray the outside of wood with a shellac or sanding sealer to seal the fibers before layering CA from thin to thick depending on the size of the crack. Use CA without a filler (ex. Copper, bronze, coffee grounds, sawdust) first then fill with the filler and CA. Depending on the depth of the crack, it can be filled with string, paper, etc. before adding the copper or other filler. If it’s turned too deeply, the string would be exposed.
If it’s a hairline crack, CA will take care of it. If larger, up to 1/16”, CA + a filler was recommended. If over 1/16”, a slow set resin or epoxy may be sturdier. Most resins require a pressure pot to prevent bubbles.
Epoxy is stronger than CA. Structural epoxy needs a lot of time to dry.
Coloring epoxy: Black Diamond powder, which includes mica, is one choice that can be added to epoxy or resin. Or, eye shadow colors from the Dollar Store is cheaper since it also contains mica.
CA requires wait time, overnight would ensure that it would be completely dry. Accelerant can be helpful, but doesn’t always dry all of the CA. One member had experienced staining from the accelerant. Star Bond brown or black CA takes much longer to dry than uncolored Star Bond.
Baking soda and CA: baking soda can work as a filler but if an object’s turned down too far, the white color will come to the surface. An experiment would be to see if alcohol inks or trans-tint dyes could work with baking soda to colorize it before use.
Resins: quick set with 2:1 or 3:1 mix ratios are available. Members had used the 2:1 for small cracks. Total Boat or Alumilite brands were recommended and their support team has been helpful to answer questions about a project. Use quick set for small cracks.
Coffee grounds work best if they are fresh and dry, not brewed.
Suggestions were given for a side of a bowl that had separated: epoxy, bow ties… Emilio Achaval (Hawaiian turner) website has information on using bow ties. One member showed a bowl with bow ties on which he’d made the bows, traced them, cut out the area then filled with the bows and coffee grounds.
Fruit trees such as pear, apricot and apple show lots of cracks and require lots of CA.
Some members see a cracked log and consider it firewood; others see it as an opportunity to add resin and make a piece of art.
Resin is time consuming. Areas may have to be reapplied and repressurized. Silicone pans make good forms for pouring resin.
Resin can be diluted with a tiny bit of acetone to change the viscosity and help it flow into cracks through capillary action. If adding color, add the color to the resin before adding the acetone. The acetone has to be added early in the process before the resin reaches the flashpoint where it starts to solidify. This should be done in a warm (70-72°) room. Amount: ~ ½ t. acetone with 4-6 oz of resin in an 8 oz cup. With a smaller amount, just a few drops of acetone.
Thinned resin can be painted on an object while on the lathe turning at a slow speed.
Sources for veneers: Woodcraft, Woodworkers Source
Voids: turn at a slower speed. A member saw a demo of punky wood being turned at 200 rpm that made a beautiful piece.
Some safety suggestions: take extra precautions, use a slower speed, wrap a piece or use fiberglass tape. A bowl in a square was shown. For safety, it was suggested to mark a safe zone with colored tape on the tool rest or to put colored tape on the wing of an object to see when it’s spinning.
In general, faster lathe speeds are helpful with solid wood or natural edges; slower with anything questionable.
Suggestions about having members organize their PAW emails to find them easier for zoom meetings: have a folder for those emails; mark it as unread; highlight it; put a star by that email.
Next discussion is on St. Patrick’s Day: show a green turning project?