Past Meeting Events
March 13, 2019 - Downdraft Table - by David Veach
The main question in how do we prepare wood for finishing comes down to sanding versus planing. Which is the best way to achieve a smooth surface without blemishes. As some of us saw with Garrett Hack’s presentation, he was skilled at doing the final preparation of the wood using a hand plane to achieve a super smooth glass-like finish. Unless you are good with setting up a hand plane and skilled at using it, you may not get the same results as Garrett Hack. It is harder to plane figured woods. You need a sharp blade. As a result, must of us resort to sanding. However, unless you are careful you can sand away fine details or round over edges.
A scraper might be able to be used, but it does not leave a smooth surface. Can you achieve a smooth surface without sandpaper? It may be possible, but can be difficult to achieve. So sanding is the next best way the smooth wood. David found that sanding without a downdraft table led to he and his wife finding dust infiltrating all of their house.
Sandpaper may go back in history since the time of the Egyptians who used sharkskin to prepare wood. It wasn’t until the 1600’s that small shards of glass was attached to a paper backing and used as glasspaper to sand wood. It was around the 1830’s that sand was used on a paper substrate to smooth wood.
Today we have all kinds and grades of sandpaper with different particles used as the abrasive agent. There is stearated and non-stearated paper. Stearated sandpaper is also known as self-lubricating sandpaper. It is used primarily for sanding wood and paint finishes as well as metal. The applied lubricant or soap prevents clogging and extends the life of the sandpaper. Garnet and Aluminum oxide can be used as the abrasive substrates on the paper. Garnet paper is inexpensive and fine for sanding bare wood but open coat stearated paper are cheaper in the long run because they cut faster and last longer.
Not all sandpapers are equal, and you tend to get what you pay for. Experience has shown that it is cheaper to buy a more expensive sandpaper because it cuts faster and lasts longer. Yes sandpaper is a cutting tool: a great number of small cutting tools actually. These cutting tools are the abrasive particles and better sandpaper has stronger, sharper particles that are arranged better.
Sandpaper made in North America is graded under the Coated Abrasives Manufacturers Institute (CAMI) while European papers are rated under the P scale dictated by the Federation of European Producers Association (FEPA). The later always has a P in front of the grit number so it is easy to tell. A grit size in one system does not exactly equal a grit size in the other, so you may want to be careful to pay attention to what system you are using.
The most important first step is to start with coarse enough paper. This is the biggest mistake beginners make. If there are major imperfections in the wood surface or the surface needs to be leveled a bit, as when a rail meets a rail on a face frame, then start with 60-grit. Sand longer than you think you need to in order to remove all of the surface imperfections. If hand sanding, using a padded block for your paper gives better results as does making the final strokes with the grain as much as possible.
The second important factor is to make small jumps in abrasive coarseness. If we take 60, 80, 100, 120, 150, 180 and 220 as being grits that are readily available, make no more than a two grit jump as you move to finer grits. Under this rule you would move from 60 to 100, 150 and 220. If you started with 80, you can go to 120, 180 and 220 grits. For power sanding you can use hook and loop backed paper because it can save partially expended sheets for later use. When using a random orbital sander, you may find it helpful to use a padded glove to prevent too much vibration being transferred to your hand.
The third important factor is sanding to a grit that is appropriate to the finish you are using. For most film forming finishes, shellac included, sanding finer than 180-grit can be counterproductive. Some like to sand to 320 or higher with some woods and if you are using an oil finish. John Kennedy will sand to 400 or 600 grit with his oil/varnish/mineral spirits finish and you cannot argue with his results. Sanding with 220 and finer between coats is helpful if you want a glossy finish. Stearated paper is much superior for sanding finishes and using waterproof paper with some soapy water or mineral spirits is a great time- and money-saving trick.
David’s downdraft table is constructed with an angled bottom with the vacuum port at the wide end. The top has chamfered holes in the pegboard to facilitate dust extraction. The downdraft table works well and really cuts down on sanding dust being spread all over your shop.
February 14, 2019 - Precision Woodworking with Jigs - by Sylvan Wells
Our February meeting included a presentation by Sylvan Wells on Precision Woodworking. Sylvan is a luthier who specialized in guitar building. Although this is a highly specialized aspect of woodworking, many of the precision methods he uses are transferable to general woodworking. Sylvan showed us several jigs that he built and uses in his profession.
A principal that guides his jig making is that you must know the “cut line”. Most of his jigs reveal where the cut will be made directly on the jig. This way the piece can be positioned on the jig and aligned with the cut line for accuracy.
He demonstrated this concept with a tablesaw jig used to cut curves in thin strips of wood for bracing. The jig rides in the T-Slot of the tablesaw. It was built oversized at first, then placed in the T-Slot and trimmed to size. This revealed the exact placement of the saw blade on the jig. In use, the strip of wood is placed on the cutline of the jig, ends clamped, and the centered bowed out into the path of the blade. After the cut, the braced is removed, and springs into its original position resulting in a concave curve. Stops on the jig ensure that this process is repeatable for all the braces.
The next jig was an adaptation of the familiar cross cut sled. His was a dedicated miniature version for cutting a 82-degree angle for “X” braces on the tablesaw. Again, the “cut line” clearly visible on the jig.
His next jig is placed directly on the guitar body with the edge of the jig, the “cut line”, perfectly aligned in reference to the guitar body. This jig guides a router for inlay work.
Jigs are not only for precision, but for speed and repeatability. Six holes need to be drilled in a guitar headstock for the tuning pins. The position is the same for every guitar. Sylvan made a jig from PaperStone (a popular material for countertops) which holds the headstock on top in the correct position. On the underside of the jig are six registration holes. A drill press is setup with a waste board clamped to it. Using an “F” drill bit, a hole is drilled into the waste board, then a registration pin of the same diameter is inserted into this hole. Each registration hole on the underside of the jig, is placed over the registration pin, one at a time, and the hole is drilled for each tuning pin.
Other tips Sylvan gave us include:
- Using Draftsman’s proportional dividers for finding the center of any number of divisions. His was an eBay find of a German made steel unit.
- Also, he avoids using pencils for marking because they introduce errors.
- Some of his jigs use a screw for fine adjustments. He standardized on ¼”-20 threads because (at 20 threads per inch) one full revolution is equal to .050” and one-half revolution is .025”.
- When needing a rectangular hole in a jig, rather than trying to cut it out, Sylvan will laminate 3 pieces of wood together, edge to edge, leaving the proper size hole in the middle. The middle board is cut to the width of the rectangle, cut in half, and spaced to the length of the rectangle. This is far easier and more accurate.
- Another eBay find was a set of metalworking transfer punches used to find the center of any hole.
- Shrink tubing is used on drill bits of any size to act as depth stops
- Using 3M brand #233 green masking tape for some clamping jobs.
- Using hide glue for visible joints and PVA for all other joints.
Sylvan wrapped up his presentation showing us a prototype of a guitar. This guitar is unique in that it has a slanted bridge and frets making each string is a different length. Hence, tuning is not wholly dependent on the tension of the strings. He got this idea from looking at pianos. Picture the shape of a grand piano. The case is physically larger in the lower octaves to accommodate the longer strings needed for base notes.
January 10, 2019 - Sharpening of Chisels and Plane Irons - by Mike Lonergan
At our first meeting of 2019, Mike Lonergan started the year off right with his presentation on sharpening chisels and plane irons.
First, he discussed some terms.
- Primary Bevel – Most chisels and plane irons have a primary and a secondary bevel on one side and a flat surface on the other side. The primary bevel can be either hollow ground or flat ground, either are acceptable. Most new chisels that come from the manufacturer are ‘flat ground’. This is also true of chisels re-sharpened on a horizontal grinding stone. Bevels sharpened on a conventional grinder with a vertical grinding stone are said to be ‘hollow ground’ since the stone leaves a slight concave curvature to the overall shape of the bevel. When sharpening the primary bevel, it is okay to switch between the two depending on the type of grinder you have available.
- Secondary Bevel – A secondary bevel is ground at the tip of the tool with a sharpening stone. It is usually just a few degrees greater that the primary bevel. Mike favors 5-degrees additional. For instance, it the primary bevel is 25-degrees, then the secondary bevel is 30-degrees.
- Backs – It is especially critical the backs of chisels be flat as these are use as a reference for working. Depending on the quality and manufacturer, chisels may need some work for flattening the back. Mike used a surface plate and sandpaper to flatten the backs.
Chisels are categorized into three groups: pairing chisels, bench chisels, and mortise chisels. Each have a different primary and secondary bevel per the chart below.
Next, Mike defines 4 levels of sharpening. Each level is more aggressive than the next
Level 1: Stropping
- Used when a chisel is sharp, but just need a minor touch-up of it’s edge. This is done periodically as the tool is being used. A piece if leather is glued onto a flat substrate, such as MDF, and loaded with an abrasive. Some use jewelers rouge or Mikes favorite, which is 1-micron diamond paste. Finally, the burr on the back of the chisel is removed by honing and stropping.
Level 2: Honing
- Used when the secondary bevel needs to be sharpened. There are many types of stones that are can be used: water stones, oil stones, dry diamond stones. Mike used the later for his demonstration. Two grades are usually necessary: Course (325 gr) and fine (1200gr). A honing guide is used to assure the angle set correctly and maintained while it is worked back and forth on the stone. For each of his honing guides, Mike created a simple jig to set back the edge of the iron from the honing guide for each of the angles on his chart. This eliminates the tedious measuring or setting by eye.
Level 3: Moderate Grinding
- Used when there is moderate damage to the edge of the chisel such as small nicks. This is done on a slow speed grinder. Mike prefers that the grinding wheel is dressed almost flat and perpendicular to the sides of the wheel.
Level 4: Major Grinding
- Used when damage to the edge is significant. This will almost require the edge be re-squared to the chisel’s parallel sides at 90 degrees. Mike uses a Sharpe felt tipped pen (substitute for machinist’s layout fluid), a miniature square, and the back of an X‑Acto knife (substitute for a machines’ marking awl) to mark where to grind the edge flat to start. Then, a new primary bevel is ground conforming to the newly established edge. Mike demonstrated this with a really abused chisel that looked like it was used for a pry bar.
Prior to sharpening, the chisel is evaluated by parring the end grain of soft wood, then placed into one of categories above. Sharpening begins with that category and proceed upward through each category until the tool is finally stropped.
- Generally, plain Irons are just like a wide chisel. Hence the same sharpening steps are used. The back needs special attention as it must firmly contact the bed of the plane and not rock. Other that that, it does not require a high polish.
- Also, when removing the burr on the back of plane irons, they don’t have to be touched off perfectly flat to the back of the iron. This is because the back of plane irons are not used for a reference, the sole of the plane is. When bedded, the tip of plane iron is hanging out in the wind, see the lower left illustration on the above chart. Mike showed us the “ruler trick”. A very thin 6-inch metal ruler is placed on one end of the sharpening stone. Then the plane iron is placed back down on the stone and over the ruler. As the burr is removed a micro back-bevel is created. This should only be done for plane irons, and never chisels.
- The tip of the chip breaker must contact the back of the plane iron when installed. There can be no gaps between the plane iron and the chip breaker, or wood chips will become trapped. Sometimes the chip breaker must be re-fetteled, similar to sharpening, the tip of the chip breaker is honed to fit flat on the back of the plane iron.
- Lastly, some plane irons benefit from a small camber to the edges, see the lower right illustration on the above chart. This prevents the corner edge of the blade from scoring the work surface. Mike showed us a trick like the “ruler trick’ to accomplish this. A thin metal ruler is placed on each side of the sharpening stone, and the one side of the plane iron rides on top of it when honing. The process is repeated for the other side. This technique kicks the angle just slightly to accomplish the camber. This is done on the secondary bevel only.
October 11, 2018 - Automated Dust Collector System by Joe Kunzman
At our October meeting Joe Kunzman presented an automated dust collector system which he built earlier this year for his own shop. A conventional dust collection system was already in place and consisted of 4” PVC pipe and plastic blast gates connected to a 4-bag Jet dust collector.
The dust collector has a switch at the base of the motor tucked in back out of sight. Finding the on/off switch required reaching around the motor and blindly fumbling around until it was located. Keeping track of which blast gates were open or closed on several tools was becoming inconvenient There were no commonly available products to address this situation.
Joe’s solution integrates three components. At each tool is a current sensor and a pneumatic actuated blast gate. He purchased the current sensors from Amazon and attached them to the outlet that the tool is plugged into. He built the pneumatic blast gates from Parker air cylinders, 12-volt 3-way solenoid air valves, and plastic blast gates from Woodcraft. There are 4 tools outfitted with these sensors and gates. Everything is controlled with an Arduino microprocessor and some specialized code that he wrote.
The logic behind the system is quite simple. When any machine is turned on the current sensor sends a signal to the controller which opens the blast gate and turns on the dust collector. When any machine is turned off the blast gate is closed after 10 seconds allowing wood chips to fully clear. When the last machine is turn off, then the dust collector will shut down after 3 minutes. This is to avoid cycling the dust collector unnecessarily.
Joe has deposited the PowerPoint slide deck and the Arduino code on our web site for anyone interested. See the following blog Post:http://www.cfwg.org/automated-dust-collector/
September 11, 2018 - Spray Finishing with Lacquer by Barry Reiter
Our friend and long-time member, Barry Reiter spoke to the Guild about spraying lacquer finishes. Here are some of the key points he covered.
- A ‘top coat’ is use for durability. For this presentation we will work with the assumption that all top coats fall into two categories: Lacquer and Polyurethane. Note that polyurethane will yellow over time, lacquer will not. Yellowing can be desirable for woods such as cherry, but unattractive for others such as blond curly maple. Choose your finish appropriately.
- The rules have changed significantly in the last 5 years. Hence, discount much of your prior notions regarding lacquer. The California South Coast Air Quality Management District (SCAQMD) now “drives the bus” for the rest of the country. See: http://www.aqmd.gov/ They are the “800 pound gorilla sitting quietly in the corner” now that the EPA is lazy with some of their industrial rule making.
- Today’s water-based lacquers are much improved from years ago. However, unlike VOC based lacquers, subsequent coats do not dissolve into prior coats. If you sand away a sag or run, or simply need to flatten the surface prior to the next application, a consequential “witness line” will be left and will not be eliminated by additional coats. Hence, good surface preparation is a must. On the positive side, water-based lacquers require reduced respiratory protection and the price of the products are coming down.
- Barry prefers solvent based lacquers. Gemini is the product that he uses. See: http://www.gemini-coatings.com/
- When choosing a lacquer product, there are three types to select from: catalyzed (2 parts mixed and then sprayed), pre-catalyzed (better flow-out and drying characteristics), and conversion (which are sometimes marketed as varnishes). When choosing the manufacturer, look to see what their target market is (such as cabinet shops, or furniture repair) and align that with your needs as formulations vary based on the needs of the user.
- He recommends buying a 90 sheen (maximum gloss) product. Satins and matt finishes all contain ground glass or sand to diffract the light. The sand can be difficult to stir into suspension and therefore difficult to match. A gloss sheen is easily reduced with steel wood and high-grit sandpaper.
- Always buy the recommended lacquer thinner from the same manufacturer of the lacquer you are using. These lacquer thinners contain the same formulation as the lacquer and will help prevent defects such as fish-eye appearing in the surface.
- Lacquer finishes require good surface preparation. Barry recommends sanding through all the grits, with the grain, to a to a minimum of 220 grit.
- To check your sanding prior to finishing, wipe naphtha onto the surface with a rag. Any defects will show and should be corrected prior to applying the finish. Remember, all finishes look good wet.
- Contrary to rumor, lacquers can be applied with a brush on small pieces. However, use a high-quality brush such as a Taklon brush.
- Turbine base spray systems (e.g. HVLP) are the preferred choice for water-based and two-part lacquers, but a bad choice for pre-catalyzed lacquer because they use hot air which causes dry spray (premature drying).
- For pre-catalyzed or conventional nitrocellulose lacquers use a spray gun with a compressor. This can be either a pot gun or a cup gun (gravity feed). The latter being good for holding the gun at odd angles. The gun you choose doesn’t have to be expensive, as the Chinese have gotten very good at copying German and Italian designs with their CNC machines; the air horn being the most critical part of a gun.
- Conventional spray guns have two critical adjustments. The needle adjustment is for regulating how much fluid is delivered by the gun. The other fan width adjustment regulates the amount of air that is mixed with the fluid to atomize it.
- All conventional guns operate best at 22-25psi “flow” pressure. Flow pressure is when fluid (not just air) is flowing through the gun. Not “static” pressure. Barry uses a miniature pressure gauge mounted on the inlet of his gun to make it convenient to set this optimal pressure.
- The technique for using a gun is important. Start and finish each row “off the piece”, overlap each pass of the gun, and maintain a wet line. For practice, use alcohol with a few drops of trans-tint dye on a piece of cardboard.
- Humidity is a concern when spraying lacquer, especially here in Florida. Too much humidity can cause a haze to appear in the finish. If this becomes a problem, Barry recommends using more lacquer thinner and using more coats to compensate for the thinning of the material. Manufactures recommendation of thinning no more that 10% is just a guideline, not a hard rule. Barry usually thins at 30% thinner to 70% lacquer.
August 9, 2018 - Laser Engraving by Tim of Woodcraft
Tim from Woodcraft discussed some of the applications the laser can do with engraving and design. If you have something you would like to have engraved, it is best to bring a sample board to test the laser cutting on that substrate. The laser at Woodcraft can cut up to 3/4″ thick. Thicker materials just may take longer. They can engrave almost any material. Acrylic and glass will work, even the stainless steel insulated cups.
The laser can engrave some very fine detail. Photographs need some contrast to work well.
Tim gave a demonstration of the laser which is behind the library in Woodcraft.
July 12, 2018 -- The Arts and Crafts Movement by Nancy Hiller
Nancy’s new book on the subject “English Arts & Crafts Furniture: Projects & Techniques for the Modern Maker” was release on June 26, 2018. So, we were privileged to see it just 2 weeks hence. This richly illustrated hardcover book features 3 construction project complete with: measured drawings, construction details, and photographs (Voysen Two Heart Chair, Harris Lebus Sideboard, and Gimson Hayrake Table). But, it was Chapter One that was the subject of her talk; that is to answer the question “Is Arts and Crafts a Style?”
Here in the US, we associate the Arts and Crafts movement with Gustav Stickley, but the movement really starts in the UK with John Ruskin (a social thinker and leading art critic of the Victorian Industrial Age) and his contemporary William Morris (a writer, lecturer, and designer who is most often associated with the movement). Nancy explained the conditions of the Victorian era that lead to up to the Arts and Crafts movement. The Victorian Era which was a societal sea change. The era starts in 1837 when most people lived in villages and worked on farms and concludes by 1901, where most people lived in towns and worked in offices, shops, and factories.
Founders of the movement saw a system that exploited both makers and consumers. They were dishonest to consumer by producing furniture that was fancy (often ornate and gaudy) and looked good (at first), but didn’t last. Factories subjected workers to horrible conditions. They were dangerous (amputations were common), exploited workers (including children), and the work was repetitive and soul sucking. This transformed work from “life affirming” to hell. Leaders of the movement believed that makers should be able to strive for perfection, hone their skills, and have the freedom to do their best work. What unifies all the examples is the philosophy underlying the movement which places emphasis on the people who built the items.
“John Ruskin saw Gothic as the ‘Antidote’ to the evils of the industrial revolution.”
Arts and Crafts as a style looked to the “moral” elements of the Gothic period, that is nostalgia for medieval culture, nature and material artifacts were “enchanted”, simpler and more transparent times, longing to re-enact or re-create nature in art, a reaction against mechanization. Nancy also pointed out that the return to simpler times and longing for nature is very cyclical – as seen again in the 1960’s, and millennials (while not forgoing technology that keeps them connected) are bringing back the “crafts” movement.
Nancy went on to explain Ruskin’s “Moral Elements of Gothic”. He listed them in order of importance:
|In Buildings:||In People:|
|Changefulness||Love of Change|
|Naturalism||Love of Nature|
June 14, 2018 -- Mike Kozikowski
At our June 14 regular meeting Mike Kozikowski showed us a china cabinet that he built for his daughter. The inspiration was a photograph supplied by his daughter. Owing to the size and complexity of the cabinet, the construction took some time; even spanning a house move.
The cabinet was built from walnut solids and veneers. It was built in two parts, a base cabinet and upper glass display, which sits on top without mechanical attachment. Mike used SketchUp to model the cabinet from the photograph. He started by importing the photo into SketchUp, allowing him to gauge the proportions. Then, SketchUp allowed him to work out dimensions and joinery prior to cutting the actual wood. By selectively hiding components, the software allowed him to isolated individual components for detailed cut drawings he could then use in the shop.
- Used frame and panel construction for cabinet sides
- 1/4″ walnut ply veneer for door panels and sides
- Joinery included double tenons
- Dovetails hold the front top rail into the posts
- Curved center door and drawer
- Used a template to band saw curved rails on carcass, drawers, and doors
- Glass upper door and curved rails glued up from stack of veneer with gorilla glue
- Shelves are adjustable with standard shelf pins
- Ordered his walnut for the project from Niagara Lumber and had a good experience, part of the order arrived not like he was expecting and their customer service department helped him get what he needed.