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Column 728
This week's column: #776 |
Previous Columns |
| April 26, 2013 #775 |
| April 5, 2013 #774 |
| March 28,2013 #773 |
| March 9, 2013 #772 |
| February 22, 2013 #771 |
| February 8, 2013 #770 |
| January 25, 2013 #769 |
| January 11, 2013 #768 |
| December 21, 2012 #767 |
| December 7, 2012 #766 |
| November 23, 2012 #765 |
| November 9, 2012 #764 |
| October 26, 2012 #762 |
| October 12, 2012 #761 |
| September 28, 2012 #760 |
| September 13, 2012 #759 |
| August 31, 2012 #758 |
| August 10, 2012 #757 |
| July 20, 2012 #756 |
| July 6, 2012 #755 |
| June 22, 2012 #754 |
| June 8, 2012 #753 |
| May 25, 2012 #752 |
| May 11, 2012 #751 |
| April 28, 2012 #750 |
| April 14, 2012 #749 |
| March 30, 2012 #748 |
| March 16, 2012 #747 |
| March 2, 2012 #746 |
| February 17, 2012 #745 |
| February 3, 2012 #744 |
| January 20, 2012 #743 |
| January 6, 2012 #742 |
| December 23, 2011 #741 |
| December 9, 2011 #740 |
| November 25, 2011 #739 |
| November 11, 2011 #738 |
| October 28, 2011 #737 |
| October 14, 2011 #736 |
| September 30, 2011 #735 |
| September 16, 2011 #734 |
| August 12, 2011 #733 |
| July 29, 2011 #732 |
| July 15, 2011 #731 |
| July 1, 2011 #730 |
| June 17, 2011 #729 |
| June 3, 2011 #728 |
| May 20, 2011 #727 |
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  Wood Acclimating
A lot of us woodworkers talk about the moisture content of the wood that we like to work with and in doing so we tend to forget about acclimating.
As with softwood just purchased from a lumber yard, if you are going to use it for indoor projects, the wood has to be allowed to dry out, or acclimated to its surroundings. Air dried or kiln dried wood must be allowed to adjust to its new environment as well.
What Is Dry?
We think of dry wood as having a moisture content of around 6 - 8% which is roughly what is expected from hardwood suppliers as they generally maintain a moisture & heat controlled warehouse.
However, when you purchase this dry wood and take it home to your shop, the dry wood will start absorbing moisture from the surrounding air. This surrounding air could be quite humid, especially in the summer months. The dried wood would rarely ever get back to its original state through absorption but the new environment will change the moisture content.
And this is good to a degree. If you start building a cabinet in a very dry shop and then place the cabinet in a room with a 50 or 60% relative humidity factor, you are going to have problems. The joints will split and even break apart. Something has to give when the wood expands and expand it will.
Shrinkage
This has nothing to do with the George Costanza type of shrinkage but, wood with a higher moisture content, say 15%, will shrink some more in a dry environment.
 Several years ago I built a pine trestle table (similar to the illustration) for our kitchen and used wood that read 14% on my moisture meter. I took it home from my shop and placed it in the kitchen, this was in August. We had a heat recovery ventilation system installed and I set the humidistat to 40%. Within a month, the joints on the table top started to shrink up to 1/8th of an inch. I then realized what was happening and quickly adjusted the system.
What’s Best?
Softwoods (pine, spruce, cedar etc.) and porous hardwoods (oak, mahogany etc.) will absorb surrounding moisture more readily than the dense hardwoods such as rosewood, cocobolo, teak and the like.
 Adjustments have to be made in the construction of any project. The majority of either soft or hard wood will more noticeably expand or contract in the width or thickness dimension. Very little shrinkage or expansion will happen in the length.
One other very important side effect of working with wood that is too moist is the wear and tear on your tools. Your tools will have to work one heck of a lot harder and shorten their life expectancy. Blades will get dull quicker as tar and pitch will build up around the teeth, sandpaper will clog up and wear out faster. The motors in your power tools will have to work harder as well.
 In this writers humble opinion, I look for wood with a moisture content between 10 and 14%, whether the wood has been air or kiln dried.
Although air drying is the least costly it ties up the wood inventory for a longer period of time compared to kiln drying. Air drying a board takes about a year to dry for every inch of thickness.
As to which method of drying is best is still up in the air, the jury is still out on this one. Our choices though are somewhat limited. If you want exotic species, you must accept kiln dried. For the domestic species, you have a choice. In either case, allow the wood to acclimatize for a week or two before using it.
Here’s the Drill
On a number of different occasions when I have had visitors in my shop, a question frequently asked is “why are you using that type of drill bit”? I guess that there are a lot of people that are under the impression that a $9.95 set of drill bits is all that is required for their shop.
 The most common of all of the drill bits used by most woodworkers is what are referred to as jobbers length, HSS bits. The HSS refers to the material (High Speed Steel) that the bit is made of and the jobbers length means that the bits vary in length in relation to the diameter. These types of drill bits are also referred to as ‘twist drill bits’.
Twist drill bits are also available in much harder metals than high speed steel. Cobalt steel is one example and Titanium is another. The latter, Titanium is usually a coating bonded to the steel. The advantages are many. You will get up to six times the wear from them, they will drill cooler, they will produce less tear-out and less downward pressure is required for drilling. Cobalt steel drill bits fall somewhere in between.
Twist drills can be used for drilling into wood, aluminum, iron, copper and soft steel, to name but a few. For metal drilling it is best to use a lubricant which will keep the drill bit relatively cool and to reduce the friction.
The best drill bits to buy are the ones with a split point and are machined at an angle of 135 degrees. These will give you the cleanest cuts in wood or metal.
Specialty Drill Bits
 If you are working solely with wood, in my opinion, the best drill bits to use are called ‘Brad Point’ bits. They look similar to twist drills except for the pointed end. The brad point bit appears to be flat (actually a slight upward arc) with a slightly lower center point. If you looked at a cross section of the bottom surface of a hole drilled by a brad point bit, you would see a slight upward cupping at the edges and a downward ‘v’ in the center.
The main advantage of these bits is that the point will start the cut and then guide the rest of the bit accurately through the wood. There is little chance of the bit ‘wandering’. They are especially suited to drilling through round and odd shaped pieces.
 There are of course, special drill bits for drilling into mortar and concrete and these are designed for either straight drilling or best, hammer drilling. The tips of these bits are made of Carbide steel and will take a lot of punishment. They should not be used for drilling into wood.
There are ‘step drill’ bits that are conical in shape and are used primarily in sheet metal work. The deeper you drill, the larger the hole. A ‘step’ in the bit tells you the hole diameter.
 Wood boring bits, also known as ‘spade’ bits are for drilling larger diameter holes and are basically a flat, vertical piece of steel that tapers into a shank. The edges, spurs and bottom are sharpened.
There are many variations on spade bits that have improved them over the years. Some have a screw on the end that helps pull the bit through the wood and makes it very aggressive.
A new type of spade bit on the market is called “Around The Corner®”. This was developed by Vermont American® for the construction industry. This very aggressive bit will allow you to drill an arced or curved hole through a beam or a joist for wiring and such.
Bigger and Deeper
 Extension bits are a special type of twist drill bit that are generally 12 inches long for those really deep holes. The fluting on them runs only about a third of the length and care should be taken when using them. Drilling must be done at a very slow speed and the bit must be removed often, to clear the flutes. If you don’t do this, you will quickly see smoke and you will burn the hole and the drill bit.
 Even longer bits are ‘power ship auger’ bits. These can be 17 inches or longer and are in diameters from 3/8 of an inch to 1 1/2 inches. A screw point guides the auger aggressively, so a slow drilling speed is best used.
A good bit to have in your tool drawer is what is called an ‘expansive’ bit. This is much like a spade bit, but it comes with a couple of adjustable cutters. The cutters are of differing lengths. One of them is screwed onto the main body of the drill bit and is adjustable. As you slide it in or out you can adjust to the size of the hole that you want. An etched scale on the blade guides you to holes up to 1 1/2 inches.
Hole Saws
Hole saws are a different breed of drill bit. These are like steel (sometimes bi-metal) inverted cups with saw teeth on the rim. Their drilling depth capacity is dependent on the depth or length of the bit. Generally around 1 1/2 inches. You can double this by reading our ShortCut Tip below. An adjustable twist drill bit (pilot bit) is attached to the shank or arbor and it guides the hole saw through its cut. A slow drill speed is best as they heat up quite quickly, especially in hardwoods. They are available in 9/16 inches to 6 inch diameters
 One other specialty type of drill bit is called either a ‘fly cutter’ or a ‘circle cutter’. This consists of an arbor that contains a short twist drill. Near the bottom of the arbor there is a steel arm that slides and is locked in the desired position. Off the end of this horizontal arm or beam is a vertical cutter. This is also adjustable and can be rotated as well. By turning it one way, you will get a clean inside cut, say for wheels. The other way gives a clean outer edge.
The fly cutter is a dangerous tool, it must be used at moderate speed and must be used in a drill press with the work piece tightly secured to the table.
Forstener Bits
A drill bit that is often mis-named is the ‘forstner’. This is a drill bit that is most desired by woodworkers because of the extremely clean sides and bottoms that it produces. One other advantage is that it will drill a perfect vertical hole down the edge of a board. As long as the point of the bit is touching wood, you can drill a semi-circular hole. The flat bottom is another advantage of the forstner.
 The conventional forstener bit is disc shaped and has two cutting surfaces on the bottom as well as two on the sides. A center spur keeps it running true. Forstners are available in 1/4 inch to 2 1/2 inch diameters.
Similar and sometimes confused with forstners, are wood boring bits. These are similar in style but they have deep cutting spurs around the bottom cutting edge. The usually have a ‘self-feed’ screw in the center. These are very aggressive drill bits so extreme care should be used.
ShortCut
To double the cutting depth (generally 1 9/16th of an inch) of a hole saw to 3 1/8 inches, first drill through one side of the work piece. Use a drill bit slightly smaller than the pilot bit in the hole saw and drill all the way through the stock. Turn the piece over, line up the pilot bit in the hole saw with the through hole in the stock and complete the job.
Delta News
For the past few months accessing the Delta web site has been frustrating to difficult as you could end up buying a new farm tractor rather than the new Unisaw. The confusion is over! Delta Power Equipment Corporation’s web site may be reached at www.deltamachinery.com . The new web site is excellent, nicely laid out and very easy to negotiate through. If you are a fan (and who isn’t) of Delta you might just want to bookmark it.
Product Recalls
 Stihl Gas Powered Tools
Stihl (pronounced Steel) has recalled a number of outdoor gas-powered tools including back pack blowers, lawn trimmers, edgers, hedge trimmers and others. Gas additives may react with the gas filler cap and distort the plastic posing a possible burn hazard. For more specific information please click here.
Our Sometimes Regular Book Review
We have a double feature this week, author/wood turner Doc Green provides all of the answers on what sort of fixture or chuck to use for that odd-shaped project. And, for the carver, Betty Padden puts a new slant on sign carving. Perhaps it was the cover that attracted me (beer) but the other nine projects are just as appealing.
 Fixtures and Chucks for Woodturning
Doc Green
176 pages
Fox Chapel Publishing
The title should be enough for even the expert woodturner to get excited about. How many times have turners fretted about ways to mount particular pieces? Author Green may in fact have the answer in this excellent and beautifully illustrated book. Green shows you how to make some excellent steadies as well as some interesting and novel PVC vacuum chucks. The author takes you through all of the standard chucks and shows how to make them work better for your turning. This is a great reference book that won’t lie around collecting dust.
 Lettering & Sign Carving Workbook
Betty Padden
160 Pages
Fox Chapel Publishing
There are 10 projects in this marvelous book that will help even the professional sign carver improve his/her skills. Author Padden is a very skilled and highly innovative carver and her book shows it. She takes you through her carvings from the first cut in raw wood through to every intricate detail including the final painting. The Paddy’s Pub sign is just one example of the author’s ingenuity but take a look at the detail in the Irish Claddagh Sign embellished with gold leaf. Even the seemingly simple Welcome sign is a work of art. It is amazing how she envisions such simple signs like a cabin nameplate. Amazing! This is one very talented lady and she deserves thanks for sharing it with us.
Fixing a Leak
 Some things are just fated to happen. Earlier today a copper pipe in our basement crawl space sprung a pinhole leak and the pipe is in close against a joist. I recalled a press release being sent to me from the PR people at Lenox and the tools they were promoting were new Tight Spaces Tubing Cutters. I thought that this would be a golden opportunity to test them when they actually arrived. I wrapped rubber tape around the leak to hold it and while doing so, the doorbell rang – it was the mailman delivering the new Lenox Cutter samples.
I immediately turned off the water and went to work. I used the ½” Tight Spaces Tubing Cutter to very nicely cut the pipe and it fit into the slightly over ½” of space between the pipe and the joist. The Tubing Cutter made a burr-free smooth cut and I was able to repair that leak in moments.
There are three sizes of Tight Spaces Tubing Cutters available, 1” ¾” and ½” and for convenience they are colored red, blue and black respectively. The  Lenox Tubing Cutters need only a half inch of space to make a clean cut and the metal parts in them are of stainless steel because you know that they are going to get wet.
Bessey Snips
The name that we respectively associate with woodworking and welding clamps also has an excellent selection of cutters and snips. The very latest is Bessey’s line of Erdi Multi-Use Snips. These Snips are very compact, measuring just under 8” in length but don’t let this fool you, they cut through sheet metal like butter. There are three configurations of the Snips, left, right and straight. We tested the D15AL (left) and the D15S (straight). Both are very comfortable to use especially with the soft rubber overmold. There is a nice index finger grip for additional leverage. The blade lock is stiff enough to stay put and not get in the way or slip into the locking position when not wanted. The blades of both snips sit close together without any play and are nicely sharp. The left and presumably the right snips will cut long and straight lines when inverting the tools. Great snips!
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