Epoxies have a wide acceptance in the marine industry, but they haven't caught on in the wood shop as well as they should. Having been associated with the marine industry myself and with the use of epoxies for many years, I have developed a good working relationship with epoxies, and I use them quite often in place of other adhesives, especially when high strength and moisture resistance are factors.

To properly use epoxy, one must first understand the basics. Epoxy is a two part adhesive consisting of a resin and a hardener, and is primarily divided into two classes: quick-set and slow-set. They are further divided within these categories by the mixing ratios, which are designed by the manufacturer. They can be anything from 1:1 to as much as 16:1, depending on curing time, viscosity, ultimate strength and intended use.

Quick-sets are usually 1:1 by volume, so that equal amounts are squeezed from hypodermic-like syringes and mixed to a uniform color and consistency. They usually achieve their strength in 10 minutes or less, and a full cure within 24 hours, but they rarely reach the high strength that the slow sets do, and quite often retain some flexibility and resilience.

Slow-sets allow more open or working time, and can take up to 24 hours to cure. The advantages are superior strength, water resistance and gap filling capability. They don't take as much clamping pressure as other adhesives, and I have had success with only contact pressure. As a matter of fact, too much clamping pressure can force the epoxy out of the joint resulting in a lean or starved joint.

The gap filling capability is no excuse for poor workmanship, but if a mistake is made, epoxy can be very forgiving. The viscosity can be altered very easily by the addition of fillers such as sawdust, wood flour, talc, or colloidal silica. I use a product called "cabocil", which I get from my epoxy manufacturer, and in fact many epoxies are pre-filled with cabocil to moderate the consistency. In an emergency repair, I have even used copper wool as reinforcement, along with the cabocil, allowing a boat owner to get to his home port before making the permanent repair.

Epoxy cures through an exothermic polymerization, or heat producing chemical reaction in which there is very little moisture loss, resulting in less than 0.05% shrinkage, the main reason that epoxy is such a great gap filler.

Probably the greatest advantage in using epoxy is the ability to join dissimilar materials. The adhesion factor is as great on metal as it is on wood, but some non-porous materials need to be roughed up to enhance the bond.

Each manufacturer has his own specifications for mixing and using epoxy, and the instructions need to be followed closely. Too much or too little hardener can result in a gooey mess that never will cure.

Storage instructions must be followed also. Some hardeners will harden from exposure to air, and water in either resin or hardener is a definite taboo. When using epoxy that is approaching the limits of it's shelf life, the resin and the hardener should be stirred thoroughly prior to mixing together. If crystals have formed in the hardener, you can sometimes restore it by immersing the container in warm water to heat the hardener enough to dissolve the crystals.

Care must be taken to avoid excessive heat and contamination of the product with water. Stir the hardener to restore the consistency.

At as much as $50.00 per gallon, epoxies can be expensive, and because of limited shelf life, don't buy larger quantities than can be used in the recommended time frame.

Most epoxies are formulated for use in moderate weather conditions, between 50 and 90 degrees Fahrenheit. Cooler temperatures slow the curing time and warmer temperatures will accelerate it. This can be used to advantage by refrigerating the mixture to prolong pot life, or by warming the mixture to speed up the cure.

Depending on the use, application can be by roller, spray gun, trowel, or putty knife. Some are thin enough to be injected into joints with a hypodermic syringe. Clean up can be done with soap and warm water if done soon enough, or with acetone, lacquer thinner, or denatured alcohol. If using a spray gun, spray plenty of solvent through the gun to assure the complete flushing of the equipment. For safety and environmental reasons, spray the solvent into a container for proper disposal.

In the past 15-20 years, I have used E-bond epoxies almost exclusively, and with around 30 different products, they have an epoxy that will fill your need. Their #1211 general purpose adhesive's viscosity can be altered easily as mentioned above, and has superior strength and bonding properties. It is a slow-set, but when I need a quick-set, I find that Loctite #01-81501has excellent properties. Visit E-bond at:
http://www.ebondepoxies.com

This article is an excerpt from an e-book I am writing. For the illustrated full version of the e-book as well as the other books I have written, click the link below: http://tinyurl.com/3chxox

Visit my resource page for products that I use in my day to day operations at: http://gcamp38-woodworkingtoday.blogspot.com/ New products are being added periodically, so check back often.

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Segments and staves are used in woodworking to form circles, arches, cylinders and polygons. Once you decide on how many sides or segments your polygon will have, simply divide 360 degrees by the number of segments.

Each segment and its radial lines form a triangle whose included angles equal 180 degrees. Divide 360 degrees by the number of segments desired, to find the included angle of the radial lines. Subtract this number from 180 degrees. Divide the result by two to find the miter angle to be cut on each end of a segment, or each side of a stave. This holds true for any number of segments.

Let us assume a pentagon, which, of course, has 5 sides. Divide 360 by 5, and you get 72 degrees. This is the included angle of the radial lines, and since a triangle has 180 degrees, the angles at each end of the segment are half of the difference between 180 degrees and 72 degrees. (360/5=72. 180-72=108. 108/2= 54) The angle at each end of the segment is 54 degrees, which is the miter angle at which you will cut each segment.

Table saw and miter saw angle scales are relative to the blade being perpendicular to the table or to the fence, so it is necessary to deduct the miter angle from 90 degrees in the above formula to arrive at the proper angle setting on the saw. The following table has taken this into consideration.

Notice that in a 3 piece project, the miter angle is 30 degrees, where a table saw or a miter saw generally do not tilt past 45 degrees. It is necessary to set the blade at 30 degrees and place the board vertically against the fence. There are some inherent dangers in doing this, as the board must be supported by some supplemental means.

First, a tall fence is required to keep the board vertical. Second, a rail should be placed on top of the rip fence, and clamped to the work piece so the work piece is supported beyond the cut to prevent the work piece from dropping into the trailing edge of the blade at the end of the cut. Alternatively, clamp two pieces together and readjust the rip fence accordingly.

A power miter saw can be used to make cuts less than 45 degrees by securing an auxiliary fence 90 degrees to the saw fence, but I don't advocate doing so unless the work piece is of sufficient length to provide adequate finger room for the operator.

This is particularly useful when cutting complimentary angles such as for forming odd shapes in decking. Use an adjustable work stand to support the board when turned 90 degrees from the fence.

Set the blade angle for the required angle, and cut one end with the board against the auxiliary fence and the other end with the board against the saw fence over the top of the auxiliary fence. Doing so in this order allows the length to be controlled against the saw fence.

Epoxies have a wide acceptance in the marine industry, but they haven't caught on in the wood shop as well as they should. Having been associated with the marine industry myself and with the use of epoxies for many years, I have developed a good working relationship with epoxies, and I use them quite often in place of other adhesives, especially when high strength and moisture resistance are factors.

To properly use epoxy, one must first understand the basics. Epoxy is a two part adhesive consisting of a resin and a hardener, and is primarily divided into two classes: quick-set and slow-set. They are further divided within these categories by the mixing ratios, which are designed by the manufacturer. They can be anything from 1:1 to as much as 16:1, depending on curing time, viscosity, ultimate strength and intended use.

Quick-sets are usually 1:1 by volume, so that equal amounts are squeezed from hypodermic-like syringes and mixed to a uniform color and consistency. They usually achieve their strength in 10 minutes or less, and a full cure within 24 hours, but they rarely reach the high strength that the slow sets do, and quite often retain some flexibility and resilience.

Slow-sets allow more open or working time, and can take up to 24 hours to cure. The advantages are superior strength, water resistance and gap filling capability. They don't take as much clamping pressure as other adhesives, and I have had success with only contact pressure. As a matter of fact, too much clamping pressure can force the epoxy out of the joint resulting in a lean or starved joint.

The gap filling capability is no excuse for poor workmanship, but if a mistake is made, epoxy can be very forgiving. The viscosity can be altered very easily by the addition of fillers such as sawdust, wood flour, talc, or colloidal silica. I use a product called cabocil, which I get from my epoxy manufacturer, and in fact many epoxies are pre-filled with cabocil to moderate the consistency. In an emergency repair, I even used copper wool as reinforcement, along with the cabocil, allowing a boat owner to get to his home port before making the permanent repair.

Epoxy cures through an exothermic polymerization, or heat producing chemical reaction in which there is very little moisture loss, resulting in less than 0.05% shrinkage, the main reason that epoxy is such a great gap filler.

Probably the greatest advantage in using epoxy is the ability to join dissimilar materials. The adhesion factor is as great on metal as it is on wood, but some non-porous materials need to be roughed up to enhance the bond.

Each manufacturer has his own specifications for mixing and using epoxy, and the instructions need to be followed closely. Too much or too little hardener can result in a
gooey mess that never will cure.

Storage instructions must also be followed. Some hardeners will harden from exposure to air, and water in either resin or hardener is a definite taboo. When using epoxy that is approaching the limits of it's shelf life, the resin and the hardener should be stirred thoroughly prior to mixing. If crystals have formed in the hardener, you can sometimes restore it by immersing the container in warm water to heat the hardener enough to dissolve the crystals.

Care must be taken to avoid excessive heat and contamination of the product with water. Stir the hardener to restore the consistency.

At as much as $50.00 per gallon, epoxies can be expensive, and because of limited shelf life, don't buy larger quantities than can be used in the recommended time frame.

Most epoxies are formulated for use in moderate weather conditions, between 50 and 90 degrees Fahrenheit. Cooler temperatures slow the curing time and warmer temperatures will accelerate it. This can be used to advantage by refrigerating the mixture to prolong pot life, or by warming the mixture to speed up the cure.

Depending on the use, application can be by roller, trowel, or putty knife. Some are thin enough to be injected into joints with a hypodermic syringe. Clean up can be done with soap and warm water if done soon enough, or with acetone, lacquer thinner, or denatured alcohol. If using a spray gun, spray plenty of solvent through the gun to assure the complete flushing of the equipment. For safety and environmental reasons, spray the solvent into a container for proper disposal.

One of the most versatile machines you can put in a shop, is the portable planer. I have had a 12″ Delta for about 15 years, and it has become my best friend. The money that I have saved in trips to the mill alone, has been more than enough to buy a 24″ stationary planer. But I have a small workshop, and even on a permanent stand, this unit is light enough to store out of the way when not in use.

There are, however, a couple of drawbacks with the portables, but these are easy to overcome. One of the most common defects is the propensity to create “snipe”, which is the over-depth cut at the beginning and the end of the cut.

The machine consists of a revolving cutterhead and a pressure roller on each side of the cutter head, and snipe is caused when a long board exerts too much force against the pressure roller that feeds the stock through the machine. Until the board contacts the pressure roller on the outfeed side, the board acts as a lever with the fulcrum being the edge of the infeed table, thus causing the downward force of the outboard end of the board to lift the initial pressure roller, sending the board into the cutterhead at an angle.

The simplest way to overcome this is to lift the board as it enters the machine, and as it exits, because the same condition arises on the outfeed side.

Portable planers have a built in safety mechanism that prevents the cutter head from contacting the platen, or bed, of the machine. This limits the minimum thickness that the machine can produce from about 1/8 ” to 1/4 “, depending on the manufacturer. In order to plane stock thinner than this pre-set, I use an auxiliary bed to effectively raise the platen of the machine, which allows me to plane to the thinnest dimension that the wood itself will allow.
I made my table from 3/4 ” Melamine, which is MDF with a plastic coating on both sides, but plywood and plastic laminate would work as well. Put a stop on the underside of the auxilliary to keep it from feeding through the planer with the stock.

Some woods, when planed too thinly, will flutter from the air movement caused by the revolving cutterhead which can allow the cutterhead to literally eat the stock. The minimum thickness for a given species of wood can only be determined by trial and error. If your machine eats your stock, you’ve gone too far.

The auxilliary bed will counteract snipe to a degree relative to the length of the bed. but I still lift the end of the board when entering and exiting the machine.

My particular machine will cut a maximum of 6″, so I have installed an aluminum angle fence, with a featherboard to hold stock square on edge against the fence, allowing me to use the planer as a jointer. When all the boards I’m using have been run against this fence, I turn them over and joint the opposite edge. This not only squares up both edges, but the boards all come to the same width.

As with all machinery, be sure to wear proper safety gear, such as safety glasses, ear protection, and gloves. Avoid loose clothing that can become entangled in moving parts. With a little TLC and sound operation, your planer should last for years.

If you would like to see the e-books that I have written on various aspects of construction, copy and paste this link into your browser:

http://tinyurl.com/3chxox



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If you have ever looked at a barrel to see how it is assembled, you will have noticed that it is constructed of segments. These are called “staves”, and the principle is used in any application where the end product is to be rounded or connected end to end in a circular fashion.

Columns, lamp bodies, bowls and turned boxes are all examples of stave construction that this article will cover.

When staves are put together in this way, a polygon is formed, with each facet or side of the polygon being a stave. Laying out polygons is not the mystery a lot of people believe it to be. Squares and triangles are easy, but when you get into pentagons, hexagons, octagons etc., things get a little trickier, but a little geometry will rescue your project.

In any polygon except a triangle, the included angles add up to 360 degrees. Once you decide on how many sides or segments your polygon will have, simply divide 360 degrees by the number of segments. Each segment and it's radial lines form a triangle whose included angles equal 180 degrees.

Let us assume a pentagon, which, of course, has 5 sides. Divide 360 by 5, and you get 72 degrees. This is the included angle of the radial lines, and since a triangle has 180 degrees, the angles at each end of the segment are half of the difference between 180 degrees and 72 degrees. (180-72=108 / 2= 54) The angle at each end of the segment is 54 degrees, which is the miter angle at which you will cut each segment. This holds true for any number of segents.

When building columns, whether turned or facetted, I like to join the staves together with splines, and I use 1/8” plywood, or door skins, for the splines. The carbide saw blades that I use cut a kerf just the right size for the plywood, and the splines add tremendous strength to the joint through additional gluing surfaces area, and they keep the staves in perfect alignment in the gluing and clamping process. If you are a biscuit joinery devotee, by all means use biscuits. They serve the same purpose, and they have the added advantage that the groove doesn’t show at the end of the stave. In either case, make sure that they are deep enough not to interfere with turning, if you intend to turn your project on a lathe.

Segments or staves can be of contrasting woods for added interest, and can be glued up in a myriad of designs like checkerboards, book matched grain patterns, or maybe a strip between staves. If using a strip between staves, you needn’t cut a miter angle on the strip, because the strip will be parallel to the miter cuts on the stave. You do, however, have to shorten the width of the stave by the width of the strip to maintain the desired overall size.

To form a base for a bowl, it is customary to cut wedge shaped segments, which, when glued together may be turned or bandsawed to form a circle that will fit a recess cut into one end of the glue-up. These segments may be the same angle as the staves, or any angle that is esthetically pleasing to you, the designer.


The Wood Explorer has a site that every woodworker needs to visit. Wood Explorer has put together a CD for your computer that details 1650 species of wood.
Here’s what they have to say about the site:

“If you are looking up information about an interesting wood in The Wood Explorer.com and wonder if there is a place where you can buy that wood, we offer an icon that will start a search for all companies advertising with us that offer that wood to either The Wood Market or The Wood Exchange.

If you are browsing casually and do not wish to buy immediately, The Wood Market is a good choice. If you are ready to buy and wish to see what stock and prices companies have, visit The Wood Exchange where serious buying happens every day”.

The CD gives you unlimited access to all 1650 species. Instantaneous display of data and ultra-fast searching. Easy, fast and customized reports. 2000 wood pictures, organized by color and type for easy identification of species. Great for comparing species.

As always, I welcome comments and questions. Feel free to respond to this post, or e-mail me at: campbell5017@bellsouth.net