Full Chisel Blog

July 11, 2013

Sharpening a Gedge or Cooks Pattern Auger Bit

Filed under: Drilling,Historical Material,Of Interest,Proper Tools,Sharpening,Techniques — Stephen Shepherd @ 9:35 am

I received a request about how to sharpen a Gedge or Cook pattern auger bit from someone who follows my blog, and I realized I had never posted about how to sharpen this type of auger before.  This is a great bit because after the led screw engages the auger bit can be tilted to almost any angle and the unique nature of its engineering allows it to cut a perfectly clean entry hole with no tear out or chipping.  And the spelch looks unusual.

gedge1

gedge2

It is absolutely crucial that the top flat remains flat, no micro bevel devil or stupid tricks for getting this type of bit to cut properly.  Try any of those hair brained ideas on this bit and it will get stuck in the hole, if it can make a hole.

gedge3

gedge4

With a fine flat file gently get the top to a shiny edge keeping the file flat on the back.  It is just like a chisel or plane blade in that you want it flat.  You can also use a small whetstone to accomplish the same purpose but keep it flat.

gedge5

gedge6

Any chips or irregularities on the cutting edge is dealt with from the inside flat bevel.  The inside on my two bits are very flat as well with no improper filing of an additional small bevel, so keep it as flat as possible even on the inside.  The smaller bit [7/8"] made by Marples had what looked like a small chip perhaps made while hitting a nail?

gedge7

 

I corrected the problem by filing it from the inside.  I used two sizes or round chain saw files to work the inside, however a round slip whetstone would have worked.  I filed the inside curve from both the top and bottom, the sweep takes a little practice to follow.

gedge8

gedge9

Once I felt a slight burr on the top, I was finished sharpening.  I don’t bother removing the small burr as it will go away after the first few times I use the bit.  The larger bit [1 15/16"] is a Cooks Pattern Patent dated 1851.  Never improperly filed it sharpened up quickly.

Here is a link to a video of this bit in use.

Stephen

June 5, 2013

Not an Oil Stone, not a Water Stone it is a Whetstone

Filed under: Historical Material,Of Interest,Proper Tools,Sharpening,Uncategorized — Stephen Shepherd @ 9:50 am

The reason for that is I don’t use oil or water or any other lubricant when I sharpen, I sharpen dry and only use water with soap to clean my stones after use.  This even applies to old oil stones I acquire; when the need arises I wash them with soap and water.  And there is a very good reason for this, actually a couple of reasons.

whetstone

 

A number of years ago back in the mid 1980′s I read an article in either Popular Science or Popular Mechanics Magazine about sharpening on stones.  The article included photomicrographs of the surfaces of both plane irons and chisels.

All samples had the same grind from the wheel and were photographed before any work on the stones.  Then one set [plane iron and chisel] were sharpened in the traditional manner using oil as a lubricant for the process.  The other set [plane iron and chisel] were sharpened using the same stones but with no lubrication on the stone.  The photographs comparing the two were remarkable.

The tools sharpened ‘dry’ had nearly perfect edges while the tools sharpened ‘wet’ showed tiny chips in the cutting edge and these were caused by, according to the article metal particles suspended in the oil.  These metal pieces were floating in the oil and striking the cutting edge causing the chips.

I immediately started using the ‘dry’ process and haven’t gone back.  I use soap and water to clean the stones when they become filled or glazed and the stone is ready for the next sharpening session.  Because it takes a while to fill a stone I don’t wash my stones that often.

Another advantage to this method is that there is little or no mess made while touching up an edge of a tool; no need to wash off the oil or dirty water before going back to work.  Give it a try and see what you think.

Stephen

 

June 3, 2013

First time working Cypress

One would think that having done woodworking for over 40 years I would have worked this wood before, but this is the first opportunity to work this particular species of wood.  I got some scrap pieces from a friend, I had told him I had not used the wood before so he gave me some cut off from a bathroom counter top he is making.

soft arkansas2

Needing a new home for my soft Arkansas sharpening stone, I decided to make it from cypress as my others were made of pine.  Having worked a lot of pine, I thought that cypress would behave in a similar manner.  Much to my surprise it worked more like poplar than pine, with little end grain collapse of the softer spring wood.  I liked how it cut under a chisel, the router plane made smooth work of the inside mortise and it stood up well under a hand plane.

soft arkansas3

In making the box I noticed that the stone was not symmetrical, one end was slightly wider than the other.  I fit it tight in the bottom but had to make the top a bit loose in order to fit on the stone in either direction.

soft arkansas1

On the bottom of the sharpening stone box I used a long fine cut headless brad, pounded it in then cut it off with pliers to form small points to prevent it from slipping when in use.

I will not put a finish on the cypress and as you know I never use lubrication when I am sharpening only when I am cleaning the stone.

I generally keep my shavings separate and put them in my compost pile, however not the cypress, it won’t decompose.

Stephen

May 28, 2013

Norton Soft Arkansas Sharpening Stone and…

Filed under: Historical Material,Of Interest,Proper Tools,Sharpening,Uncategorized — Stephen Shepherd @ 9:25 am

it came in a different box.  Going through some old watchmaking/clockmaking tools last week, I came across this box, saw the name Norton on the outside, then as I was about to open the box I saw that it was labeled ‘India combination stone’, it being man made I wasn’t interested but opened the box anyway.

soft arkansas

It did not look like any India stone I had ever seen, so I slipped it out of the box and to my surprise it was marked Soft Arkansas and is in near perfect condition, very flat on both sides.

Not ever judging a book by its cover, I am now going to look in all containers no matter what they are labeled.

Stephen

May 3, 2013

The Complete Cabinet Maker And Upholsterer’s Guide – J. Stokes 1829

stokes1829

Gary Roberts over at Toolemera has done it again and reproduced a fine tome from the nineteenth century.  The book has many full color plates, hand colored engravings and Mr. Roberts has reproduced the entire book in color, so the pages appear as they would in an original edition.

Mr. Stokes has done an excellent job at assembling material from his peers and predecessors, which I won’t call plagiarism as it was common practice.  Some of the engravings have the long f for the s, indicating an earlier time.

The book is however full of very useful information about lay out, perspective, drawing, design and construction of furniture, with an emphasis on finishing, which I found fascinating.  This is a great hardbound edition of an historical work that is a pleasure to hold in ones hand and read about the past and the ways of old.  Add this one to your bibliotheque.

Stephen

January 16, 2013

Boxwood and Slate

My Christmas gifts arrived

This year my family changed from the usual gift exchange in the spirit of giving to a you can steal someone else’s gift in the spirit of taking.  My objections were overruled and I decided to play my own game.  I bought a gift card from Lee Valley, so that no one else in my family would be interested.  After choosing lots [my comment about deciding who is to die in a survival situation, got some chuckles] I was number 4 to draw and chose my own gift.  My sister objected and I told her she couldn’t change the rules in the middle of this evil game.  Needless to say we will be going back to the regular gift exchange next year.

Cashing in on the free shipping offered by Lee Valley, I picked up several turned and threaded boxwood containers.  I could not even buy the wood locally to make these at this price, not including labor.  Great items and very well made.

boxwood containers

I tried to order a staple-less stapler, but for some reason they can mail them to an address in the US.  I wonder if they are considered as personal protection devices or the magazine is too big?  Strange.

slate1

I also purchased a piece of slate, had to order the middle size as they do not ship the large size for some reason.  I thought it would be flat on one side but it was split and had uneven surfaces.  I checked their website and that is what they listed.

slate2

I however wanted to use it for writing with chalk or soapstone so I needed to smooth the surface.  I started with a coarse file and float, then converted to a piece of industrial sanding belt that had grit the size of cracked pepper and got it flat.  I then used a card scraper to remove the scratch marks.  The scraper was great, I did have to resharpen it during the process, the slate was abrasive to the scraper.  [I do have a piece of English Slate sharpening stone and it is very hard].

Stephen

January 11, 2013

Shepherds’ Compleat Early Nineteenth Century Woodworker – First Review

bookcover2

This is the first book review of my first book that was originally published in hardbound in 1981.  This review appeared in Smithsonian Magazine April 1982.

smithsonian1

smithsonian2

 

 

I found this while doing research at the University of Nevada, Reno at their excellent library.

Now I need to find the reviews in Workbench Magazine, Soldier of Fortune Magazine and Museum of the Fur Trade Quarterly.

Available at Tools for Working Wood

and The Full Chisel Store or from Amazon.  Amazon also has original hardbound editions for sale.

Stephen

September 29, 2012

Traditional Tanged Spokeshave Workshop – Reno, NV Sept. 2012

The workshop for the Nevada WoodChucks was a success, at the end all of the people had a usable traditional spokeshave with a tanged blade.  When I teach workshops, I build one to show the various steps, but in this case I didn’t have an opportunity to finish the one I was working on as I had to help a couple of new students with their project.

I did manage to finish mine when I returned home.  It is fancier than most I have made, I usually go for an earlier style like here.

Joe has taken my class before and here he is concentrating on his task of smoothing the throat.

Ed, a vetern of several workshops I have taught in Reno goes about forming the throat of the spokeshave, good two handed technique.

Rod [on the right], another repeat offender brought a friend to audit the class.

Jim is a first time participant in one of my workshops.  I spent additional time with him and Skip another first timer.

Charlie, my youngest student ever [6 years old] had an impressive set of tools, his dad Chuck a turner said his son owned all the bench tools.  Photo below shows a trusting father, with a bit of concern in his look.

Chuck and Charlie watching Rod at work on his spokeshave.

I demonstrated how to use a burn auger and a video was made so here it is.  We turned the fan on after the first one to prevent the smoke alarm from calling the local fire department.

burn auger video

The spokeshave blades required sharpening, which was done with a file.  Two of the blades proved to soft and needed to be heated cherry red, quenched in water, polished bright and heated to temper with a straw color, then quenched.  The spokeshaves were all finished with Moses T’s Gunstocker’s Finish.

Stephen

 

April 4, 2012

Making a Veneer Saw

There are several current models of veneer saws being produced, the nicest is perhaps the one offered at Tools For Working Wood with interchangeable blades.  I have made a couple, and have orders for two more saw blades.  I needed to make this now as I need to cut some walnut burl veneer for replacing the top of a sewing machine cabinet for a friend.  There is no way to cut this crispy veneer without a veneer saw.

This is the end of a saw blank for a patternmaker’s saw, which was longer than I intended, I cut and snapped the end off to make the veneer saw.  The tip already was slightly curved which helped in the shaping process as veneer saws are severely breasted.

I had to remember to file all of the teeth in the same direction, which took me a bit of time, I kept skipping a tooth.

Once the teeth were all filed in the same direction and with the curve or breast formed, I filed off the teeth to knife points.

I drilled two holes in the saw plate and countersunk them on the proper side for mounting to a wooden handle.

This is my current veneer saw [on loan]:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Stephen

 

January 26, 2012

Cutting Wooden Threads

Spiral threads have been cut in wood for centuries.  I discussed making thread by hand earlier.  During the nineteenth century the tools had been perfected but still retained their original design.  There are two components to threading; there is the screw and the nut.  The screw has external threads and is referred to as the male element and the nut has internal threads and is referred to as the female.  While these can be meticulously cut by hand, it is much easier to accomplish this by using some simple tools.   There are two tools used to make the threads by hand and they are the tap and the die or die box or screw box.  Wooden threads can also be cut on specialized lathes from a design first proposed by Leonardo da Vinci.  This discussion will be about using the two hand tools to make the threaded screw and nut.

There is nothing quite like creating wooden threads.  The process is a unique experience and the results can be rewarding.  You are capable of making your own wooden screw clamps, veneer presses, vices and adjustable items such as music stools, embroidery frames and candle stands.  Threading wood is something unique, a wooden nut and bolt is unusual, something that few others have.  The projects, tools, furniture and fun things you can make with a set of these tools are endless.  Wooden threads have always intrigued me; there is just something fascinating about them.

Wooden Thread Cutting Tools

There are two ways to go, the first is to buy a set of wooden thread cutting tools or you can make your own.  The new wood threading tools are of good quality and generally follow traditional designs.  If you choose to make your own you will need to have made a tap of the proper size that you are interested in making.  This should have sharp edges to make clean cuts; a machinist or good blacksmith can fabricate a tap to your particular dimensions.  These taps are similar to modern metal cutting taps except they are larger and have fewer teeth per inch.

Eight teeth per inch is about the minimum for a ½” tap and larger should have 6 teeth per inch and on very large screws for presses 4 TPI to withstand the pressure.  To make a tap the threads can be cut in the metal for the tap and then the four sides flattened to produce 4 cutting edges at each thread.  Regular taps have a tapered end to make it easy to start the tool into the wood.  Bottoming taps are not tapered but will cut to the end or the bottom of a blind hole.  Do not use a bottoming tap for initial threading as it can easily cut off centered internal threads.

There is another old design that has the threads machined on the outside and a hole drilled in the center of the end of the tap.  On the end of the tap, the threads are machined down to form the taper and at the first thread a small hole is drilled at an angle into the large center hole.  This forms a very sharp tooth that cuts and the chips go through the small hole and out the larger hole in the end of the tap.  This type of tap does produce a very smooth cut, but the traditional 4-sided tap, if it is sharp and used properly will also produce clean cuts.  The wooden handle should be strong and long enough to give leverage for the sometimes difficult process of cutting internal threads.  The handle should be rounded and shaped to fit the hand as the hand is touching the handle a lot during tapping.

Once the tap is made it is possible to make the die box and all that is required is a V-shaped cutter that is secured in the box and cuts the external threads.  Unlike the tap, which will cut with four cutters on each thread, the die has only one cutter that cuts all of the threads.  A proper sized hole is drilled for the tap into a piece of hardwood such as beech or maple, see list below.  This hole must be square to the body of the die box.  The holes are then chamfered or countersunk to prevent the tap from splitting out the wood as it enters and exits the hole.

The tap should be lubricated with linseed oil to make the threading easier.  The tap is then inserted carefully into the hole and started squarely to insure a straight threaded hole.  It is very important that the tap is started perpendicular to the surface and square to the hole.  If the tap binds up gently back a ½ turn then start again, if it becomes too difficult, remove the tap, lubricate and try again.  Make sure the exit hole is countersunk to insure that the tap doesn’t break out any wood when it exits.

Now that you have the die box drilled and threaded, the next step is to cut a mortise for the V-shaped cutter that is on the front leading edge of the die box.  The cutter is positioned right over the first complete thread peak at an angle of 30ºand the leading edge of the cutter should engage the wood at the widest part of the cutter first to score the wood being removed.  The end of the cutter is ground at an angle of 15º with the top of the V leaning forward, with the bottom of the V trailing.

The cutter needs to be sharp and set to cut just slightly deeper than the threads that were cut by the tap.  This insures that the newly cut external threads will not bind up in internal threads of the die box.  The die box can also be equipped with a removable plate that will center round pieces as they are fed into the screw box.  The plate needs to be thick enough to line up the piece to be threaded and removable so the external threads can be cut all the way up to the shoulder of a turned piece if necessary.  The internal threads of the screw box should be well lubricated to make the cutting of the screw shaft easier.

Nut – The Nut is the part with the internal threads that are cut with the Tap.  The nut is prepared by drilling the hole using the following starting holes sizes.

Starting holes:

½” threads use a 3/8” drill

¾” threads us a 5/8” drill

1” threads use a 7/8” drill

1 ¼” threads use a 1 1/8” drill

1 ½” threads use a 1 3/8” drill

1 ¾” threads use a 1 5/8” drill

2” threads use a 1 7/8” drill

2 ¼” threads use a 2 1/8” drill

2 ½” threads use a 2 3/8” drill

 

It is important that the hole is drilled square and perpendicular the flat surface of the nut.  The wood for the nut should be a wood that is capable of taking the threads.  While most hardwoods will hold the threads some are better than others.  Beech, maple, hickory and oak can be used for nuts and will take threads, as can alder, elm and poplar.  Some brittle woods such as cherry are difficult to thread, but it can be done.  The thicker the piece of wood that is threaded, the stronger the threads will be.

On thin pieces for the nut, the threads can easily be cut at an angle, so make sure the hole is straight and the threading is done properly.  When threading in an angled hole, the grain orientation is important as is beginning the cutting with the tap.  The tap needs to go straight down the hole; if you get off at an improper angle the threads will be too deep on one side and too shallow on the other.  While the internal threads on the nut are not as critical in terms of strength, the screw needs to be constructed of specific woods.

After the proper sized hole is drilled, the edges need to be chamfered or countersunk to prevent split out during the entry and exit of the tap.  This must be done on both sides, as the tap will chip out the wood.  The tap is lubricated with linseed oil or beeswax and it is inserted in the starting hole.

It is very important to make sure that the tap is perfectly square and lined up with the hole.  The tap is twisted and forced into the wood, taking care to make sure that it is perpendicular to the surface of the nut. Enough downward pressure is exerted to engage the tap into the hole, after the cutting begins, the tap is self-feeding.  If the tap binds in the hole, gently and carefully back it off a half a turn and start again.  If it still binds, back the tap out of the hole, lubricate it again and carefully start the tap back into the cut threads.

Be careful when doing this so you don’t cross thread the screw and ruin your work.  Every once in a while, back the tap out a half a turn and continue until cutting becomes more difficult, then repeat and go at it again.  It is better to take your time and make sure that the work is done properly.  Continue until the tap comes out the exit hole, clean out the shavings and back the tap out of the hole.

If you are threading a blind hole, your starting tap will hit bottom, then back out the tap, remove the dross and carefully place the bottoming tap into the threads and run it down until it cuts the internal threads on a blind hole.  If the wood is fuzzy on the inside of the threads, I wet the piece with water and raise the grain.  I allow it to dry completely and run the tap down the hole again to remove the raised grain and fuzz.  Sometimes running the tap in from the opposite direction will remove the fuzz and clean up the internal threads.

Screw – The Screw is the part with external threads and is cut by the Screw Box or Die.  The selection of the material for the screw is important as certain woods make excellent threads while others are more difficult.  Softwoods are difficult without an extremely sharp cutter in the screw box.  Hardwoods are preferable and woods such as beech, maple and hickory are the best for wooden bolts or screws, those with external threads.  Strong, tough woods such as elm are better than brittle woods like cherry.  Walnut also accepts threads as well.  With care any wood can be threaded.

It is also important that the grain be as straight as possible.  This is for strength and for a more uniform cut.  The piece to be threaded should be turned to the size of the thread box.  Therefore if the threads are for a 1 ½” screw then the dowel or piece should be turned to just under 1 ½”.  All it takes is just a 32nd under to make the piece just the right size.  It may take a slightly smaller say 16th under to get a proper fit, it may take some experimenting.  But I guarantee if it is too large the threads will crumble as it is forced through the screw box.  If it is too large it will not fit into the screw box and if it is too small it will not properly thread through the screw box.  A slightly smaller screw works much better than one that is too tight.  I like nice crisp threads, so I always turn the pieces just under the required size.

For some applications where you don’t necessarily need sharp peaks, such as heavy duty tools, the screw blank or dowel can be slightly undersized producing flat topped threads instead of sharp peaks.  Small fine threads such as 8 threads per inch can be difficult and these fine external threads can easily break off.  Denser woods work better for these fine threads.  If the dowel is undersized, it is important to make sure that the screw box travels over the dowel in a uniform manner to insure proper threading.  If flat-topped threads are required, I usually turn the dowel to the proper size, thread the piece, then re-chuck it in the lathe and turn off the peaks.

When you turn the screw or dowel on the lathe, just use your gouges and chisels, do not use sandpaper.  The sandpaper can leave residue in the wood fibers that can dull the cutter in the screw box.  Also you will want to chamfer the edge of the dowel or screw blank to make it easier to start the screw box.

I always dip the end of the screw blank or dowel in linseed oil to provide lubrication for the cutting process.  I usually clamp the screw blank in a vice to hold it during the threading process.  It is important to make sure that the screw box engages the screw blank or dowel perfectly square to insure accurate threading.  I always look down the waste hole in the screw box where the chips come out to see how the cutter engages the threads.  I try and exert enough pressure to engage the wood on flat grain first rather than the side grain.  It just seems to start better if the cutter enters the wood on the flat grain.

Once the cutter has began to make threads they engage and pull the screw blank into the screw box, so the pressure can be reduced.  After cutting begins, simply turning the screw box is sufficient.   When the cutter has made the first part of the threads, they will engage the internal threads of the screw box and advance the screw into the tool creating a perfectly cut spiral thread.  The first ½” or so is usually not perfect and I always allow for an extra half inch or so to cut off after the threads have been cut.

Once the cutting has started, the tool should ‘sing’ through the work.  If the stuff is tight in the tool, the cutter may be set too shallow or the dowel is too large.  Most screw boxes have a removable plate that guides the screw blank into the screw box.  This is removed if the threads are to be cut up to a shoulder.  The plate should be used to cut well into the screw blank and can be removed to thread just the last inch or so.  A properly positioned and very sharp cutter will make the cutting much easier.

It is important that you keep your tools sharp and well maintained.  The teeth on the tap need to be clean and sharp at their cutting edges.  The new made tap and die sets require sharpening.  The screw box has a V cutter that needs to be honed mirror shiny on the outside and perfectly flat on the inside. The V-shaped cutter in the screw box should be ground at the proper angle of 15º and should be very sharp and properly positioned.  The bevel is ground on the outside of the cutter.  Both edges must be honed for a good clean cut.

New set of ¾” taps and V-cutter, factory ground, NOT sharp.  Note improper ground V-cutter, burr protruding from the bottom of the V.

New set Sharpened.  Threads and slots have been dressed and V-cutter sharpened and honed.

The tap needs attention as well.  The V-teeth need to be dressed to remove the grinding burr left during manufacture.  Make sure to get both sides of the slot and both places where the slot and the V groove meet, especially on the leading (cutting) edge.  Use a triangular file to dress the teeth.  Use a thin flat mill file to dress the gullets so the cutting edge is sharp.  Then go back and re-dress the V-grooves with the triangular file to remove the last of the burrs.

The sharper your tools the easier the work.  I use a bit of sandpaper over the files to hone the edges to a mirror gloss.  Your holes need to be clean, straight and countersunk and your turnings need to be of the proper size and chamfered to produce the desired results.  Use linseed oil or beeswax to lubricate the parts being cut, it just makes the job easier.  Make sure the tool engages the work squarely to produce quality work.

Clean out any shavings that can interfere with the cutting operation.  Work slowly and carefully.  This is not like cutting metal threads; it is a continuous operation, only backing out when the cutters jams or the cutting is complete.  After you are finished using the tool make sure to clean off all excess linseed oil before it dries!

There is no end to the possibilities for using wooden threaded devices and the results are delightful.  Wooden screws are capable of exerting incredible pressure when used for clamping applications and can provide for ease of assembly and disassembly for transportable furniture.  There are endless applications and uses of wooden threads and they are fun to make.

Stephen

Older Posts »

Powered by WordPress