Jacksonville Fair

I’ve been working on my entry to the annual Jacksonville Fair woodturning competition. I can’t show the piece until the fair starts next week, and because it’s not finished yet 🙂

This image was my entry at last year’s event. Norfolk Island Pine hollow form decorated with pewter leaves.

Split Turned Legs

I am building a custom vanity cabinet.  The design features a couple pairs of split turned legs either side of each door opening.   I thought I would take the opportunity to document the process involved in creating a split turning.  Split turnings are typically used in furniture and architectural applications, as decorative elements.  The process has other applications in woodturning, including the “Lost Wood Process”.

The Merrimam-Webster dictionary definition is as follows:

 a turning (as of a baluster) split vertically and applied decoratively (as to the surface of a chest or cupboard) or used as a spindle in a chairback

Dompkowski - Vanity (shaded(

 

Essentially the process involves gluing two pieces of wood together with a piece of paper sandwiched between them.  The piece is then mounted on the lathe and turned to the desired shape.  Once the turning is complete the paper joint is split using a chisel, the paper literally splits in half, yielding two identical half turnings.  A simple process, but there are a couple of important things to watch out for.

Dompkowski - leg

The design of the split legs I needed is fairly simple.  It is a cone, approximately 32″ long, tapering from 3″ diameter to 1″ diameter.  I started with a couple pieces of 8/4 maple, about 6 1/2″ wide and 33″ long.  One face was flattened at the jointer.  Just as with any glue joint, it is important to have the two mating surfaces flat.

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The piece was then ripped in half at the table saw, yielding two pieces of 8/4 maple, each 3 1/4″ x 33″.

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The only paper that I have personal experience using is the brown builders/construction paper.  It is available from the home improvement retail stores and is typically used as a paint drop or to protect new flooring from damage by subsequent trades.  It is a fairly thick paper, probably a little thicker than a brown paper bag.  I’ve read that you can use newsprint or a brown paper bag, but I don’t have any experience with that.

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In order to have a successful and stress free glue I’ve learnt that you need to get everything prepared in advance.  As well as clamps, glue and spreaders, this also involves cutting the paper to size.  I also like to fold the paper over the edges of the wood so that it is easier to place in the correct position once the glue is applied.

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It is very important to note that you are gluing the paper to both pieces of wood, so you need to apply the glue to both pieces of wood.  If you think of it in terms of a sandwich analogy, where the two pieces of wood are the slices of bread, and the paper is the meat in the sandwich, you need to put the mayo (glue) on both slices of bread! 🙂

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Once the glue is applied to both pieces of wood, place the paper over one of the pieces …

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… then place the other piece of wood on the paper, and clamp together.  I like to leave the assembly clamped overnight.  The glued up blank now measures approx. 3 1/4″ x 3 1/4″ x 32″.

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After removing the clamps, I clean up the ends of the blanks at the miter saw and mark the centers of each blank.  Actually, the one center line is already determined by the glue join, I just mark the other line.  When placing the blank on the lathe it is very important to position the centers accurately at the head stock and tail stock.  The center determined by the glue line is actually more important than the other center line.  If the glue line is not placed directly on center, then the two pieces once split will not be identical.

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I like to use a steb or safety center at the head stock.  This enables me to turn a bit more aggressively with out worrying about damaging the piece if I get a catch.

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At the tail stock I use a cup live center.  It is VERY important to use a cup center at the tail stock.  If you use a cone center then you will split the two pieces apart as you tighten up the tail stock.

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The turning on this design was not very complicated.  As I mentioned before, it was a straight taper from 3″ diameter to 1″ diameter.  However, it can be challenging to achieve a perfectly straight taper.   In order to determine some guide points I drew out the leg design life size on a piece of construction paper.  I was now able to use this drawing to determine the diameter of the finished leg at five intermediate points evenly spaced along the leg.

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Once the piece was turned round, I marked the points along the leg …

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… and using a parting tool and a pair of calipers, established the correct diameter at each of those points.

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Use a spindle roughing gouge I then turned the leg just a bit bigger than the final diameters.

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The final diameter and taper was established using a 1 1/4″ skew chisel.

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In order to further smooth and straighten the taper I use the following trick.  First, with the lathe running slowly, I draw a pencil spiral down the length of the leg.

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I then attach a piece of 120 grit sandpaper to a piece of plywood with some spray adhesive.  I run this up and down the leg as it is turning slowly.

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Wherever the pencil marks are sanding off indicates a high point.  So I am then able to refine those high spots with the skew.

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The piece is now sanded smooth.

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The moment of truth arrives!  Time to split the turning.  This is done by placing a sharp chisel directly on the paper glue joint and gently driving it into the joint with a hammer.

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It is a little slow to start …

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… but once the split is started the two pieces separate very easily.  Actually, it is always a bit disconcerting as to how easily they come apart, considering that a short while ago they were spinning rapidly on the lathe!

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A couple images of the pair of split turned legs.  The paper still needs to be removed.  This can be done with sandpaper, although depending on the size of the piece I will often make a shallow pass over the jointer to remove the paper.

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Wooden Collar with Threaded Pewter Insert

In this post I’m going to share my technique for making a wooden collar for a hollow form with a threaded pewter insert.  In previous posts I have shown how I cast, turn and thread a pewter collar for a hollow form.  I’ve also shown an easy way to cast a texture onto a pewter collar for a hollow form.   Aesthetically, the main difference with this collar is that when the finial is screwed into the collar there is no pewter showing, however I am still able to retain the functionality of the threaded pewter.  It is a nice way to showcase a special piece of wood on the top of a hollow form.

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In this example I am using a small piece of rosewood burl.  It is about 3/4″ thick and I have cut it into a rough circle about 2 1/2″ diameter on my bandsaw.  With the jaws of my chuck closed I am holding it against the jaws with the live center.

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This enables me to round it over and turn a shallow dovetail tenon on the piece.IMG_0864

I then rotate the piece and mount it in the chuck jaws so that I can drill a 1″ hole with a forstener bit to a depth of about 1/2″.

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Using a thin shop made parting tool I then cut a groove into the wall of the hole that I have drilled.  The idea here is to form a shallow groove to make a mechanical joint for the pewter.  The parting tool was made from an old sawzall blade.

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Here you can see the groove.  It is about 1/8″ deep.  I find it easiest to stand on the far side of the lathe when turning this groove.

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The piece is then taken to my melting pot and molten pewter is cast into the hole.  When the pewter has cooled it is a good idea to wick some thin CA glue into the joint between the pewter and the wood.  The groove provides a mechanical joint that prevents the pewter from coming out of the hole.  However the forces involved in drilling and threading the pewter are likely to cause the pewter insert to spin in the hole.  Applying the CA glue at this point will prevent this from occurring and any CA residue will be turning off later in the process.

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The piece is mounted back on the lathe and a 3/4″ hole is drilled through the piece.  IMG_0870

Using a lathe tap holder, the threads are tapped into the pewter.  As you can see I forgot to wick the CA glue into the joint between the pewter and the wood.  The pewter stayed fixed while I was drilling, but as soon as I started threading it started to rotate.  you can clearly see the CA residue on the surface of the wood which I will turn off shortly.

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A close up shot of the tap and the threaded insert.IMG_0872

The top surface of the collar is now turned and a seal coat of shellac applied.
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A 1/2″ male adapter is now mounted in a pair of long jaws and the collar is turned around and screwed onto the adapter to allow me to finish the underside of the collar.

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Another shot showing the collar held on the lathe with the PVC male adapter.IMG_0875

The underside of the collar is turned.  A tenon is turned to allow it to be attached to the opening in the hollow form.  The bulk of the collar is also reduced, as is the threaded pewter insert, while still leaving some threads to accept the finial.
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A shot of the top surface of the finished collar.IMG_0877

A shot of the underside of the finished collar.

PVC Gouge Handle with Aluminum Insert

I buy my bowl and detail gouges from Thompson Tools.   They come unhandled and I have always turned wooden handles for them.  I enjoy the process of turning a handle for a tool that I will be using for a number of years. However, as I have started to travel more for demonstrations, I’ve found that it is pretty challenging to pack long handled gouges.  So I decided to make some new handles for my bowl and detail gouges.

A couple of years ago I saw Mark St. Ledger demonstrate at the Florida Woodturning Symposium.   As well as thoroughly enjoying his demonstration, I remembered the handles he was using on his gouges.  I’m not sure what he was using as an insert, but I do remember that the handle was made from PVC pipe.  I decided to see if I could make something similar.

I ordered a length of 1 3/8″ aluminum round bar and also brought some 1″ Schedule 40 PVC.  I chose the Schedule 40 over the other variety they had in the big box store as the Schedule 40 had thicker walls.

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The first step was to cut the aluminum round bar into 2 1/2″ lengths.  I did this using a v-block on my bandsaw.

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I then mounted the length of aluminum round bar on my lathe using the long jaws of my chuck and drilled it.  I find that I get more accurate results if I drill the hole out in increments of about 1/8″ diameter.  On this particular insert I needed a hole of 1/2″ diameter.  So I first drilled a 3/8″ diameter hole …

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… and then drilled the 1/2″ diameter.  I also used a bit of oil to lubricate the bit.  The hole was drilled all the way through the aluminum round bar.

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Without removing the round bar from the long jaws, the next step was to face off the aluminum using a detail gouge.

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I then turned a 1 1/2″ long tenon to match the internal diameter of the PVC pipe, approximately 1″.

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A test fit to make sure that I had a snug fit and PVC butted square up to the shoulder of the tenon.

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I then supported the PVC pipe using a 60 degree live center in the tail stock.IMG_0819

I turned the section of the round bar up to the chuck jaws down to match the external diameter of the PVC pipe.
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I then sanded the PVC pipe using 80 grit to get rid of the lettering on the pipe, and then worked my way through the grits ending at 180.  This left a surface that felt good, relatively smooth with a bit of texture.

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I reversed the round bar in the chuck jaws … IMG_0822

… and finished turning the nose of the insert.IMG_0823

Moving to the drill press I drilled a hole in the insert.  I held the insert steady using a v-groove block while I was drilling.

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I then tapped the hole with a 1/4 – 20 thread.IMG_0825

Finally, I mounted the insert back on the lathe and just cleaned up the inside of the hole again.

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Completed sanding the insert and a bit of polish.  All shiney 🙂
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The next step was to make a hardwood plug for the other end of the handle.  I chose to make this from African Mahogany, firstly because I wanted to include some wood in the handle, but also because at this stage I was pretty tired of turning aluminum.  The steps to make the end plug were exactly the same as for the aluminum insert with the exception of all the drilling and tapping.

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Once the hardwood plugs were made I expoxied them and the aluminum inserts into the PVC pipes, and gave the handles a couple coats of matt lacquer. IMG_0833

Hero shot of  the completed set of handles!IMG_0834

The African Mahogany plugs.  They look great against the white PVC.
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The business end of the handles showing the aluminum inserts with socket set screw.

 

 

Turning Hollow Forms Pith to Pith

I turn a lot of end grain hollow forms, primarily because I am adding a pewter collar to them and so need the wood to be in as stable an orientation as possible.  About 6 months ago I started turning end grain hollow forms from a whole log mounted pith to pith.  I was a bit apprehensive about it at first, worried that the base of the hollow form would be inclined to crack as it had the pith included, but after rough turning  and finishing a number of them I have been encouraged with the results.  I thought I would share the process and some of my thoughts and observations on turning a hollow form pith to pith.

Before I go any further, I do need to acknowledge and thank Ed Malesky from the Turning Arts Group for his advice and the discussions we have had on the topic.  Ed also publishes a blog which you might consider following.

Typically an end grain blank is cut from a log as shown in the diagram below.  As well as a lot of chainsaw and bandsaw work, getting a reasonable size (5 to 6″ diameter) blank for a hollow form means that you need a fairly big log to start with.  Once the blank is cut there is also the danger of it cracking if it is not turned right away due to it being such a thick piece of wood.  For that reason it is also very difficult to purchase an end grain blank from any of the online stores.  The vendors are concerned about larger blanks cracking and most will only offer end grain blanks, or spindle blanks, up to 4″ diameter.

end grain blank in log

So the first advantage of turning hollow forms pith to pith is that you do not need a particularly big log.  Depending on the position of the pith, a log in the 10 to 12″ diameter will easily yield a 5 to 7″ diameter hollow form.   The second advantage is there is not much chainsaw work needed in order to prepare the blank.  One simple crosscut to cut off a section of the log and you have your blank ready to mount on the lathe.  Because of the ease of preparing the blank it is also possible to leave the wood in log form until it is needed, further reducing the likelihood of cracks.

From an aesthetic view, I feel there is a lot more symmetry and balance to a finished vessel turned pith to pith compared to one turned from a blank cut out of a log to exclude the pith.  This symmetry and balance is visible in both the grain pattern and the distribution of the heartwood.  You can see this in the two images below of some rough turned end grain hollow forms.  The one on the left was turned pith to pith and you can see how the annual growth rings flow completely around the form.  By contrast, the vessel on the right was turned from a blank that did not include the pith, and the growth rings tend to run vertically up and down the piece.

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The images below show the difference in the balance of the heartwood.  In the vessel on the left, turned pith to pith, you can see the heartwood distributed evenly all round the hollow form at both the top and the base of the form.  The vessel on the right,  turned from a blank that excluded the pith, only shows the heartwood along one side of the form.

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The following images should provide a photo essay of the process of rough turning a pith to pith hollow form.  The first step is to cut an appropriate length off a leg.  Allow a couple inches extra either side for turning away any cracks on the end of the log and also for holding the log while hollowing.  In a perfect world the pith would be located in the center of the log, however this is pretty rare.  I take the end of the log that has the pith closest to the center, which should yield the largest diameter on that section of the log, and drive a 4 prong spur drive directly into the center of the pith.  This will be the end that is the top of the hollow form.

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I mount the log between centers, placing the live center directly into the pith on the tail stock side.  Depending on how offset the pith the log will not be very well balanced and you need to pay attention to the following:

  • The banjo may not clear, so you might need to start turning at the tail stock side and move towards the head stock side as the log is turned cylindrical and clearance is made for the banjo.
  • Check the clearance on the tool rest by rotating the log by hand before turning the lathe on.
  • The log will be out of balance, so start the lathe at the slowest speed possible and only increase the speed as the blank is turned cylindrical and becomes more balanced.
  • Wear a face shield and take care when turning the bark off.  Depending on the bark you can get some pretty big chunks flying off.  If the bark is loose it can be removed before turning.

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I like to use a spindle roughing gouge to true up the blank, but you could also use a bowl gouge.  I will turn the blank to a cylinder and then true up the end at the tailstock.  I try and get it slightly concave as this is the end I will be mounting my face plate to.

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I then remove the blank from the lathe and attach the face plate with wood screws.  In order to center the face plate I have a piece of scrap wood that has been turned so that it just fits into the opening of the face plate.  It also has a hole drilled in the center to accept a transfer punch.  I place the transfer punch in the dimple in the center of the blank, drop the piece of wood over the transfer punch and then drop the face plate over the piece of wood.  Then I will screw the face plate to the blank.  The face plates I use are made from 1 1/4″ nuts and are not very deep so I need to take care that the dimple on the blank does not restrict the face plate from being threaded all the way back onto my spindle when I mount it on the lathe.

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Once remounted on the lathe it may be necessary to turn away some of the wood at the tailstock side first to get past the cracks that were visible on the end of the log.  Once that is done and I am clear to solid wood I will shape the outside of the form, leaving some bulk at the base to give stability during the hollowing process.   I like to leave the tailstock live center in place for additional security while shaping the outside of the form.

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Then I will drill the form to finished depth with a forstner bit and mark the depth of the hole on the outside of the form.  When drilling I allow for the length of the screws holding the faceplate on plus at least an inch to allow for the parting cut and the base of the hollow form.

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I will then hollow the vessel out.  I try and maintain a fairly even wall thickness and don’t leave the walls too thick.  This is especially important at the base of the hollow form where the pith is.   I have a tendency to walk a fine line here unfortunately.  Because I am adding a pewter collar to the form my natural inclination is to leave a bit of extra thickness on the walls towards the base in order for the piece to feel balanced and not top heavy due to the pewter collar.  I have had a couple of rough turned pith to pith forms crack at the bottom and believe it is mainly due to me leaving to thick a wall at the bottom.

Once done with the hollowing I will shape the bottom of the vessel.Then after double checking the depth of the vessel,  I will make a parting cut about 1/2″ wide leaving a tenon about 3/4″ in diameter.  Finally I will create a dovetail tenon on the very end of the blank.  The diameter of this tenon is restricted by the face plate and is quite a stretch for the jaws of my chuck, but it will be sufficient for remounting the piece at a later date and doing some light turning and sanding.

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In the image below you can see the tenon between the base and the hollow form.  I’ve found that this tenon will invariably bend as the piece dries as it is essentially the pith of the log, however it forms a natural breaking point and any cracks that are likely to develop in the base will generally not transfer to the hollow form.  The dovetail tenon formed by the face plate is also visible in the image.

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The form is then unscrewed from the faceplate, I write the wood species on the underside of the base and then it goes up on the shelf with the rest of my rough turned hollow forms to dry.

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I will cover the final turning of the hollow form in another post, but before I close I want to add a couple observations and things to watch out for.

The image below shows some small cracks at the base of the hollow form.  I’ve found that these cracks can normally be turned away once the hollow form is remounted on the lathe after drying.   To confirm if this is possible I will first take a light and look inside the hollow form to confirm that the crack has not gone all the way through the wall or base.  If I don’t see any evidence of the crack on the inside of the form I will mount it on the lathe and carefully reshape the base to turn away the crack.

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I’ve learnt the hard way not to be greedy.  Turning pith to pith means just that.   The turning must start with the drive center and live center placed directly in the center of the pith.  The two hollow forms in the image below were turned from the same log.  The pith was far from the center of the log and so in order to maximize the diameter of the hollow form, I placed the live center in the center of the log, not in the center of the pith.  Not only is the heartwood distributed unevenly, but the rim of the hollow forms have warped so badly that I’m not sure I’ll be able to salvage these two.  Surprisingly enough, neither have cracked.

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The image below is a great example of the thick base cracking but the crack not extending through to the hollow form.

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The closing shot below shows a group of rough turned hollow forms.  You can clearly see the small tenon separating the heavy base prone to cracking from the hollow form.

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Textured, cast pewter collar

During my demonstration at the Symposium in Tampa I showed a couple variations of my cast and threaded pewter collars for a hollow form.  One that seemed to generate a lot of interest is shown in the image below.  I thought I would share the details on how I make this collar.  It is a very simple technique and allows you to cast the texture directly so that the topside of the collar does not need to be turned.  The technique gives you a very organic texture and the collar, because it is not perfectly round, has a natural edge look to it.

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The first step is to create the wooden mold.  I made this one on the lathe using dry maple and simply drilled a 3/8″ deep hole with a 2 1/4″ Forstner bit.  Then you will need to raid the kitchen for some aluminum foil.

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Tear off a piece of the aluminum foil and fold it double.  Then crunch it up so it is all wrinkled.  Carefully open it up and line the mold with it, trying not to smooth out all the wrinkles.  You don’t need to get it to form fit the mold, all you are trying to achieve is a general dished shape.

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Pour the molten pewter directly onto the aluminum foil,  wait for it to cool and then …

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… pop the textured collar out from the aluminum foil.  At this point you can mount it on the lathe in a chuck and  drill and tap the threads.  Then sand the top surface of the collar with some steel wool before applying a patina and then sanding again with steel wool.IMG_0527

The image below shows a detail shot of a similar collar in a suspended hollow form.

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Images from the 2013 AAW Symposium ~ Tampa, FL

The 2013 AAW Symposium in Tampa, FL was a great event!  It was held in the Tampa Convention Center which is in a beautiful setting near the water.   The Symposium ran very smoothly and it looked like everyone was enjoying themselves.

I personally had a great time.  My demonstrations went well, I spent some time in the Instant Gallery which is so inspiring, I brought some new tools home with me from the vendor area, I made some new friends and I spent some quality time with old friends.  What more could I have asked for!  Kudus to all those involved in the organizing and running of the event.  You did a great job and should be proud of yourselves!

What follows are some of the images that I took at the Symposium.

Cast and Threaded Pewter Collar and Finial

The following are my demonstration handouts for the “Cast and Threaded Pewter Collar and Finial” demonstration presented at the 2013 AAW Symposium in Tampa, FL.

Pewter is a non-ferrous metal alloy primarily made up of tin (85 to 99%), with the remainder consisting of copper, antimony, bismuth and lead.   Modern pewter’s contain no lead and are actually Britannia metal.  One noteworthy use of pewter is the Oscar statuettes.  They are made of Britannia metal plated with gold.  The melting point of pewter is approximately 375 degree Fahrenheit (190 degrees Celsius).  The low melting point and non-ferrous nature make pewter a great candidate for incorporating it into turned pieces.  A regular propane torch can melt it and it can be cut, drilled and turned with regular woodworking and woodturning tools.

Pewter can be purchased from online metal stores where you can expect to pay around $20 per pound.  The frugal among us can also find it sold in ingot form on eBay, where you can typically win with a bid of about $12 per pound.  The eBay sellers are normally selling melted down pewter mugs, plates etc. As such you take your chances regarding the lead content, although many claim the pewter is lead free and include pictures of test results.

Molten pewter being poured into wooden mold, using a “bottom pour” electric melting pot.
Molten pewter being poured into wooden mold, using a “bottom pour” electric melting pot.

While pewter can be melted in a metal ladle, I use a small electric furnace or melting pot made by Lee Precision.  This is the same pot used for reloading or casting fishing weights.  They cost around $60 and are available from most hunting or sporting goods websites.  One of the advantages of using this melting pot, aside from not having open flames in the workshop, is the pot is a “bottom pour”.  Molten pewter contains a fair amount of “dross”.  These impurities float to the top of the mix.  With a “bottom pour” pot, when you lift a handle the molten metal flows from the bottom of the pot into your mold, leaving the “dross” in the pot.  I have found the spout clogs occasionally, so I keep a propane torch on hand to melt the solid pewter clogging the spout.  A casting thermometer is also very useful.

Molds can be made from a variety of materials.  I use both wood and silicone to make molds.  The silicone I use is sold by Smooth-On.  It is called Heat Resistant Mold Max® 60 Silicone.  I use this when I have spent time and effort creating a master and want to be able to cast a number of collars from the same mold.  For one off collars I will typically just make a wooden mold.  They are cheap, quick and easy to make and the collars poured in them can easily be embellished at the lathe.  The wooden molds have a limited life span as the heat from the molten pewter causes them to warp.  I use kiln dried maple for my wooden molds.  The moisture content of the wood needs to be low in order to minimize the possibility of it turning into steam and expanding.

When casting and pouring the pewter make sure you take all safety precautions.

  • Never leave the melting pot unattended while plugged in.
  • Place the melting pot on a ceramic tile.
  • Wear thick gloves and safety glasses.
  • Allow the pewter to cool fully before trying to de-mold it.  Sometimes it can appear solid on the surface but still be liquid inside.
Drilling the collar on the lathe.
Drilling the collar on the lathe.

I typically make my collars between 2 and 2 1/2” in diameter.  This size works well for a hollow form from six to 12 inches tall.  More important it allows me to easily mount the poured collar in my chuck for further work on the lathe.  The first step is to drill a ¾” hole through the collar using a Jacobs chuck in the tailstock.  Technically, for the size tap I use the hole should be 47/64”, but a ¾” drill bit is more readily available and being off by 1/64” doesn’t seem to make much difference.

Once the hole is drilled I use a NPS 1/2-14 tap to tap the threads in the collar.

Side note: NPS refers to Nominal Pipe Size.  This is different to NPT which will produce a tapered thread.  The ½” description can be a bit confusing as well, especially as we have just drilled a ¾” hole!  It refers to the internal diameter of the schedule 40 pipe that this size thread is used on.  The 14 refers to the threads per inch.

 

A shop made lathe tap holder
A shop made lathe tap holder

The tap is held on the lathe by means of a Lathe Tap Holder.  These are available for purchase, but they are relatively easy to make.  I made mine from a section of 1 1/8” aluminum rod which I drilled on the lathe.  The idea behind threading on the lathe is to keep everything centered on the centerline axis of the lathe.  The first collar I threaded, I did by hand holding the collar in the vise on my workbench.  When I put the collar on the hollow form the finial was not plumb and stood at an angle!

The pewter collar being threaded on the lathe.
The pewter collar being threaded on the lathe.

It is important to use some form of lubrication when threading or tapping metal.  Although the pewter is a soft metal and threads/taps very easily, you will get a far better finished surface using lubricating oil.  In lieu of actual threading oil I just use some regular 3 in One oil.

Now that the collar is tapped, wipe it down and soak it in some acetone or denatured alcohol to get rid of the excess oil.  We now need to mount it to the lathe in order to turn a tenon on the underside and shape the top.  I use a “27 cent chuck” I get from the hardware store to do this.  A ½” PVC male adapter is held in my chuck and then the collar is threaded onto this.

The underside of the tenon being turned. It is threaded on a ½” PVC male adapter which is held in a chuck.
The underside of the tenon being turned. It is threaded on a ½” PVC male adapter which is held in a chuck.

I turn the underside of the tenon first.  I turn a tenon which is slightly larger than the hole in the hollow form.  (I find it is easier to size the hole in the hollow form to the tenon than the other way around.)  I then reduce the bulk of the collar by shaping the underside.  Because the collar is held to the lathe by means of a PVC adaptor, I can cut right to the threads and into the PVC collar without worrying about damaging the gouge.

I then remove the collar from the PVC adapter and rotate it so I can turn the top.  Wear gloves when removing the collar from the PVC adapter!  The collar will have become pretty tight on the adaptor and the metal edges can cut you.  Once the top of the collar is shaped it needs to be sanded/polished before embellish.  Any embellishing tool you would use on a box top or spinning top can be used on the pewter.  Chatter tools, Wagner texture tool, Sorby spiral tool and the Decorating Elf can be used, and the embellishments outlined with the tip of a skew chisel.  These embellishments can also be further enhanced by applying India Ink, allowing it to dry before wiping it off.

The top of the collar being decorated using the Decorating Elf.
The top of the collar being decorated using the Decorating Elf.
India Ink being applied to enhance the embellishments.
India Ink being applied to enhance the embellishments.

When I turn the hollow form I use a faceplate and I do not part the hollow form off initially.  I typically hollow end grain and so do not experience a lot of movement as the piece dries.  Now that the collar is complete I mount the hollow form back on the lathe and size the opening to fit the lathe.  Once I have achieved a snug fit, I attach the collar to the hollow form while it is still on the lathe.  I use 5 minute epoxy and put it around the opening of the hollow form.  I then insert the collar and lightly clamp it using a 60 degree live center in the tailstock.

The next step is turn finish turning the bottom of the hollow form.  Ideally I will allow the epoxy to cure overnight, but if you are careful the epoxy is strong enough to allow the next step within about half an hour.  After removing the faceplate from the hollow form, mount the ½” PVC adapter in the chuck and then screw the hollow form onto it.  Place a live center in the tailstock and bring it up to support the hollow form.  Part the hollow form almost through, just leaving a little nub.  Shape the underside of the hollow form and sand.  Slow the lathe down and cut through the last of the nub.  If you have allowed the epoxy time to cure the hollow form will be secure enough on the PVC adapter that you can finish sanding the underside.  Keep the lathe speed slow though!

We now need to turn the finial and attach a threaded ring to it.  A simple mold for the pewter ring can be made by drilling a 7/8” hole in a block off wood a couple of inches deep.  The pewter is then poured into that.  Allow the pewter time to cool.  This might take a while as it is a pretty large volume of pewter.  To remove the pewter from the mold, drill a hole in the block of wood from the underside and use the knock out bar from your lathe to knock the pewter free.  It is then mounted in pin jaws in the chuck; drilled with a ½” drill, turned to 53/64” diameter and then threaded using a Round NPS ½-14 Die held in a Lathe Die Holder.  Don’t forget to use some form of lubrication.

A shop made lathe die holder.
A shop made lathe die holder.

You will not be able to thread the entire column as the die will stop at the pin jaws, but thread at least ¾”.  What is not used can always be melted and used again.   Turn the exposed end of the column true and then part off ½” of the threaded column.

The base of the finial needs to be at least 7/8” diameter or it will just screw right into the hollow form!  I leave a tenon on the finial which is about ¾” long and exactly 1/2” diameter before parting it off.  The threaded pewter ring is then attached to the tenon on the finial using 5 minute epoxy.  Apply the tenon to the inside of the pewter ring and not to the finial tenon.  By doing so any excess will get pushed out the ring where it will be turned away later.

Finial Holder

The final step is to clean up the underside of the tenon on finial.  I do this by mounting a length of 2” PVC pipe using my chuck jaws in expansion mode.  In the open end of the PVC pipe I place a piece of scrap wood with an appropriately sized tenon.  The wooden insert has been drilled and threaded in the center so that the finial can be screwed into it.  It helps if you cut a slit with a bandsaw from the edge of the wood to the center, making a “collet” chuck.  The wood is then friction fit into the PVC pipe with the finial inside the pipe and the underside of the tenon exposed allowing you to turn it true.

The finished collar and finial.
The finished collar and finial.

2013 AAW Symposium ~ Tampa, FL

Things have been quiet on my blog the last two couple weeks as I have been getting ready for the 2013 AAW Symposium being held in Tampa, FL at the end of this month.  I will be demonstrating at the Symposium and all of my spare time lately has been devoted to preparing for this.

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I’m really looking forward to the Symposium.  As well as a great line up of very talented demonstrators there is so much else to see and do.  The instant gallery, billed as the largest display of turned wood objects under one roof, is a sight to behold and I plan on spending a couple hours there.  There is also the juried exhibition, this years theme is “Currents”.  Not to forget the Vendor area where you can pick up that last tool that stands between you and greatness!  You can read more about the symposium at the AAW website  or download the Symposium Planning Guide.

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My demonstration will be on casting and threading a pewter collar and finial for use in a hollow form.  I will be doing two rotations, one on Saturday and one on Sunday.  If you’re a reader of my blog feel free to say hi and introduce yourself.  It would be great to meet you and talk a bit about turning.

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Hope to see you in Tampa!

Tissue Box Cover – Part 2

Last week I covered the cutting of the four sides and the top for the tissue box cover.  This week I will be showing how I embellished the sides and top with some wood turning.

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The first step was to lay the parts out in the order in which they would be assembled.

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I then laid out where the opening for the tissues would be and also drew some decorative circles to indicate where the embellishments would go.  The center of the 6″ circle falls directly at the intersection of two sides and the top.  The center of the 4″ circle falls at the intersection of two sides and the center of the 5″ circle is offset from the intersection of two sides.

The idea is to have the turned embellishments wrap around the sides and top of the assembled box.  The layout for the embellishments that fall on two faces is not that critical, however if the embellishment falls on three faces then it is critical that the center of the circle is exactly at the intersection of the three faces, or the embellishments will not flow around all three faces.

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I started with the 4″ circle and put double-sided tape on the back of the two faces that it fell on.

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I then stuck the two pieces on a 12″ plywood circle which was attached to a face plate.  I lined the two pieces up so that the center of the circle was at the intersection of the two pieces.

A couple of notes about the plywood backing.  I used two pieces of 3/4″ plywood laminated together and rough cut to 12″ diameter.  The double thickness helps to stiffen the piece and reduce vibration and flex at the circumference.  The laminated plywood was then screwed to a face plate  mounted to the lathe and turned true.  It is important to use a face plate with set screws and tighten the set screws to the lathe spindle once the face plate is mounted on the lathe.  If you don’t use set screws there is a danger of the plywood continuing to turn after the lathe is shut off, and it will then unscrew itself from the lathe!

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Once the pieces are in position I like to apply pressure to the double sided tape for a couple of minutes.  I place a scrap piece of wood over the parts and applied pressure with the tail stock.  I also applied pressure to the corners of the scrap wood with some clamps.  A couple of minutes under pressure makes the double sided tape stick much better.

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After removing the clamps, scrap wood and tail stock, I turned the lathe on at a very slow speed and standing off to one side slowly turned up the speed.  I let it run for a couple of minutes and then checked to see that the pieces were secure and had not moved.  Once I was satisfied they were secure I turned a hemisphere in the center and some further embellishments with a texturing tool and skew.

  • While turning I kept the speed fairly low, around 1000 rpm.
  • Don’t skimp on the double sided tape.
  • Apply pressure to the tape for a couple of minutes to increase the adhesion strength.
  • Rotate the plywood before turning on the lathe to make sure nothing comes into contact with the tool rest etc.
  • Keep your hands and fingers behind the tool rest!
  • Take care removing the parts from the plywood.  Slow, gentle and constant pressure will cause the tape to slowly give.

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This was the 5″ circle which was offset from the intersection of the two sides.  I added a scrap piece of maple to help counter balance the offset weight.

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Last, I turned the embellishments that would flow over two sides and the top of the tissue box cover.  It was critical that I align the center of this circle with the intersection of the three pieces.  I also added a scrap piece of maple in the one corner to counter balance the weight and also to help provide support to the cuts I was making.

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I then moved to my scroll saw and cut out the opening in the top for the tissues.

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The five parts laid out again.

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I laid some clear packing tape across the four sides, flipped them over, applied a thin bead of glue to the four sides, then rolled the parts up into a box …

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… and taped it together.  The tension created as the tape is stretched when rolling the sides up is more than sufficient clamping pressure for this assembly.

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I then applied a thin bead of glue to the four bevels of the top …

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… and taped it in place.

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The finished tissue box cover.