Bowl Turning with a Pole Lathe

I thought I'd put a few thoughts down on my development of bowl carving with a pole lathe. I have being using a pole lathe for a few years now, mainly turning spindles for different projects. I made my own lathe from a design similar to design from the "Association of Pole Lather Turners" and this has the usual headstocks with the one on the right having an adjustable pin so that the work is held tight when turning. With spindle work, this seems to be important as often the spindle works itself loose making progress impossible so you soon get into the habit of checking the tightness when you are turning.

Pole lathe made for spindle turning.

The lathe is easily dismantled as it does not have glued joints or screws and depends on a set of bolts that hold it in position very firmly. I designed my own adjustable tool-rest using pine dovetailed with a strip of oak where the tools actually rest when turning. This has worked very well and I have turned several types of wood including beech (kiln dried and green), oak, alder, birch, rhododendron, ash, box, elder, sycamore and field maple.

More recently, after moving to Devon, I did a course with Sharif Adams in Dartmoor using the pole lathe to make bowls. This was a one day course and covers a lot of information. During the day I made a bowl from beech a great experience and I can thoroughly recommend the course. In addition Sharif has made a series of videos going through all the steps of turning and also sharpening the tools.

 I soon realised that my set-up for spindle turning wasn't going to be suitable for bowl turning and I needed heavier headstocks and ironware to hold the bowl. The spindle tool rest was not adjustable enough and so a new tool rest was needed. However, I don't have room for two pole lathes and as the lathe I made was basically quite bulky and sturdy, I decided to make new headstocks using the iron ware from Sharif. He also makes the tip-up and tip-down chisels and runs courses to make the tools as well but I bought mine from him a few months after the course. With new headstocks, it would be relatively easy to change from bowl turning to spindle turning by changing the headstocks and tool supports. Another difference I noted was that most of the bowl turners take the cord that wraps around the mandrel directly from above so that the cord attaching to the bungee (or pole if you have one) is vertical. The mandrel attaches to the bowl and together with the paracord, drives the bowl so that you get about two and half turns per push down on the treadle.

My first beech bowl made on the course. Centre stub still to remove.

First I made the headstocks so they fitted the lathe and provided enough mass and bulk to hold the bowl blanks. I used epoxy resin to hold the tips and made sure they were in line with each other.

New headstocks with adjustable tool rest.

The next job was making some mandrels to attach to the bowl for turning. I used some ash wood that I turned on the spindle lathe, one larger one, about 2 inches diameter and 11 inches long and a smaller one for smaller bowls about 1 1/2 inches diameter and 8 inches long. I made the smaller one so that it attached to the bowl  blank by a cylindrical tenon joint about 1 in long and 3/4 in diameter. The corresponding mortice had to be drilled to the right depth in the bowl top. The other mandrel was made to attach by four spikes that were then used to penetrate the blank and hold it in position.  I drilled vertical pre-holes into the flat end of the mandrel, one in the centre and three at 120 degrees. Using large screws (70 x 5 mm) with no threads near the head, I screwed them in place with the centre one protruding more than the others and then sawed the heads off at an angle (to make a chisel end) and all facing in the same direction. The longer central screw (placed in the central hole made when turning the spindle) made it easier to place the mandrel in the centre hole of the blank before hammering the rest of the spikes. I guessed the mandrel would hold better if the spikes were hammered in with the chisel ends across the grain of the wood of the blank. The outside spikes protruded 2.2 cm, useful to know when undercutting the core!

The large Ash mandrel with spikes in place. Note that I have enlarged the mandrel diameter near the headstock end to help keep the cord in place.

I'm not going to say much about the cutting tools as they are covered in Sharif Adams Blog. The two I bought were the "tip-up" tool with the cutting edge on the left with the tip facing up and used for most of the turning, and a "tip-down" tool used with the tip facing down and the cutting edge on the other side.. I made some Ash handles from a quarterised log of Ash, again setting the irons in place using a tight fit with epoxy resin and treating with linseed oil. These should last a few years if the tip are protected.

"Tip-up"cutting tool all ready to go (I hope!)

Close up of the "tip-up"

First attempt at a small bowl.

I'm just going to go through how I got on with my first "solo" bowl. This will give you some idea of the problems I faced as a novice and the stages.

Close to the source of the birch tree that was previously felled and available.

I used a log of downy birch I had obtained from Scotland in the summer so it had been sitting around outside for a while and had the start of some spalting where the wood had started to decay but not of course rotten in any way. I chopped a blank and set-in the mandrel with a mortice and tenon joint so it gave a very tight fit.

The small downy birch bowl with mandrel attached.  This is my first attempt at forming the outside of the bowl.

I used the "Tip-up" tool to shape the outside but had some difficulty because the bowl wasn't very symmetrical and I seem to get a lot of scraping action rather than fine peeling. From this I decided that the cutting edge wasn't sharp enough as I tried different cutting angles. I also found that I needed to wrap the cord around twice to get a decent grip on the mandrel. I then tried a leather strap around the mandrel (Chlorino Chromnylon belt, LL1, 3000x10 mm from George Lodge and Sons, Hull)) and found this gave a more positive drive.

My first attempt at the base using the "Tip-down" tool to form the stub and cut the slightly concave base and then "Tip-up" tool to get a smoother finish. More work to get a better finish is needed, so work in progress. Some nice spalting detail is visible.

Made a rough rim with "Tip -up" and started the inside of the bowl using "Tip-down" near the centre and "Tip-up" going down hill starting in centre region and working out.

The "Tip-up" tool wasn't as sharp as the "Tip-down" so I bought a DMT diamond conical sharpener, extra fine and used this on the inside and a small extra fine flat diamond on the outside keeping the outside surface perfectly flat. I then cut the rim using this tool and at last got some nice fine shavings.

Next I made an initial attempt on the bowl using the "Tip down" tool to excavate near the mandrel and by twisting the blade so that I was using the edge nearer the tip, and brought depression towards the outside. I then used the "Tip up" chisel to gradually move the hollow to the outside by starting near the lip of the depression and moving to the centre but stopping where the curvature went uphill. To my relief this was easier and I was able to produce some nice fine continuous shavings.

The next step was to excavate again near the mandrel and extend the mandrel cylinder further into the bowl. I found this difficult with my lathe set-up as to get a good angle the tool was operating close to the rim and that meant I had to change pushing legs and move to the left. I also found it important to move the tool rest closer to the bowl.  I think the most important lesson so far is that, with both tools, you need to get the tool touching the wood so it isn't cutting (back face to the wood) and than then make a slight twist to start the cutting. Anyway, I stopped at this stage to revise my progress and also to rearrange the lathe to make it more comfortable to use.

In desperation with the bad weather including continual rainfall, I moved the lathe into my workshop. It just fits and allows me to continue indoors at a leisurely pace.  I continued to smooth out the outside of the bowl but found one section very tough as it was ripping the grain. I also included some channels using the 'Tip down' tool around the outside to add some individual character . I also made a rim to the bowl with a chamfer to the outside and continued excavating the inside, firstly removing material from the core with the "Tip down" and then using the other tool to move from the bottom inside of the bowl (at about the 7 o'clock position) towards the centre (fixed pivot on the tool rest) and then moving into towards the core. This also involves pulsing and rotating the tool to get the optimum contact with the wood. The birch was by now fairly dry and hence hard to work compared with the beech I'd used on the course. I finished the inside with the "Tip down" tool with the nose on the wood and a slight twist to get a nice cut. Working from the outside this produced a good finish. It also enabled me to go close to the core and also reduce the core from the side with the tool almost touching the top edge of the bowl. I found that it was impossible to get good contact with the core in this way as the angle was too steep and the blade kept digging into the core. I tried the 'Tip up' tool to work at the base of the core and this was more successful in removing material without snagging. Eventually the blade cut through to the mandrel tenon and I was able to break off the core from the bowl without any difficulty (the diameter of the core was less then an inch).

Finally I cut off the remaining core in the centre of the bowl and on the outside with a gauge and skew knife ready for further drying and treatment with walnut oil.

Bowl carved ready for further drying and treatment with Walnut oil. It is about 100 mm diameter and carved from a section of  Downy Birch I collected in Scotland in the summer of this year. This is the first bowl made without the watchful eye of Shariff Adams

Bowl after drying for a week and three treatments with walnut oil.

Second attempt making a small bowl.

I found a quartered log of Ash freshly felled that looked suitable for making a shallow bowl. The wood seemed quite dry (I think the water content of Ash is low even when green). I roughly shaped it using a hand axe and saw followed by a roughing or scrub plane to get the top and base flat. After this I scribed a circle 16 cm in diameter for the top and 7cm diameter for the bottom. I then mounted the blank on the larger of the two mandrels (two inch diameter) with the chisel edges of the spikes across the grain for better anchorage. This is where the longer spike in the centre of the mandrel was useful as it allowed me to position the mandrel in the dead centre of the scribing point. I estimated the centre on the bottom by rotating the blank balanced on the top centre and adjusting the bottom point to give a smooth rotation. I will play with the bottom point when the weather is dry and I can do this on the pole lathe. As I haven't any fixed plans for the shape yet apart from the fact that it will be fairly shallow so it needs a reasonable wide base for stability but this could be less than 7 cm without any problems.

Bottom of bowl roughed-out ready for lathe work. Notice that there is a flat area that I'll need to watch when I start the lathe work and this to an extent will govern the outside diameter of the bowl.

Top of bowl before turning. This looks fairly ideal with about 3/8 inch spare from the line all round.

Bowl on mandrel held with spikes. The blank isn't as symmetrical as I would have liked. The flat rim at the top of the bowl is about 3/4 inch wide

After finishing the small birch bowl, about a month later I continued with the larger Ash bowl. It had been stored in a plastic bag in a box in the workshop (December, so it was cold in there). I decided to follow Shariff Adam's sequence and cut the outside curved surface of the bowl first. The flat area was a nuisance and needed quite a lot of work to get the a clean cut around the outside of the bowl. To start with I did a fairly rough cut around the bowl from my inner circle line and going to the outside edge. The shape more or less formed itself with steep sides near the rim of the bowl. I followed the technique taught by Shariff of cutting with small arcs with a pivot on the rest bar and moving along the bar to the outside of the bowl, The wood felt dry and needed a sharp blade. Once I had a fairly clean cut on the entire external surface my plan was to go on and form the base and stub of the bowl and return later to refine the curved surface and rim of the bowl after sharpening the "Tip-Up"  blade. I can now appreciate that doing the external curved surface of the bowl as the first job allows you to get a feeling for the best shape for the bowl and this in a way determines how you progress with the rest of the bowl.

The Ash bowl after the first session "rough cutting" the exterior curved surface. The wood colour and detail in the bowl are beginning to appear. The next jobs are cutting the base and foot followed by the rim chamfer.

After another session I had made an attempt on the base and foot and started on the rim and inside of the bowl. I couldn't do the rim without first flattening the top with the "Top-up" chisel. I tried a bevel on the rim but it was not good and couldn't get a clean cut. The wood seems very fibrous and tears easily so I suspect I need to get the cutting edge sharper. I used the "Top-down" chisel to get a wider flat rim and so I will see how it develops once I have done the inside.

Outside of the bowl after cutting the base/foot and tidying up the rim and top surface.

Starting to excavate the inside of the bowl.  The wood seems very fibrous and it is difficult to get a clean cut on every surface. The wood is dry and so I stopped and took some time to sharpen the chisels before progressing.

I continued to excavate the bowl, deepen the core and also the steepen the side near the rim of the bowl. Sharpening the chisel improved the cutting and carving was fairly trouble free.

After another short session, the inside of the bowl is starting to take shape. There is still a lot of wood to remove but I won't go too far without improving the finish on the outside.

Then I tidied up the outside and rim of the bowl with the "Tip Up" tool and continued working on the inside until I was satisfied with the shape and wall thickness. At the rim this was about 8 mm. I found the core difficult to deepen because the tool handle caught on the rim when turning the core down. In the end I excavated the core near the bottom with the "Tip Down" tool about 1 cm wide channel being careful not to cut into the bowl bottom. I then used the "Tip Up" tool to deepen the channel below the main core until it was less than 1 inch diameter and ready for breaking. This was below the reach of the nails in the mandrel (a disadvantage in using this type of mandrel is that care is needed not to make contact with the cutting edge of the tool).

Ash bowl ready to dry, now 178 g.

Ash bowl after a few days drying and treating with walnut oil.

Here are a couple of spalted ash soap bowls that I've made. I used the tenon (7/8 inch diameter) mandrel to attach the bowls. They have been treated with Danish oil and will next be treated with polyester resin to make them waterproof. The bottoms have a concave base and rim to allow water to drain. The holes are 7/16 inch diameter. I am still finding the undercutting of the central core difficult but will practice!!

Soap bowls turned from spalted ash wood.

Spalted ash bowl, trying another shape mainly dictated by the blank.

I have included an account of my experiences in the techniques : 
BOWL CARVING…some notes



 TOOLs: Two tools, “Tip up, TU” and “Tip down, TD”, OC : O Clock. Lathe bed about nipple height, with 1 stroke about two revolutions with a Chiorino leather belt.

1.       Outside of the bowl.

Shariff Adams does this first and then does the base/foot so it depends how you feel about it. Use the TU tool for this with left arm on the tool rest and right hand holding handle 2/3 the way along. Can start with the handle away from the body (not under the arm at this stage). Basically place the tool about 7 OC (O Clock) and make small arcs (with pulsing) amounting to a downward diagonal pass starting near the centre. It is important to adjust the blade so it starts by rubbing on the back and as you twist the handle, it makes a clean cut. The tool pivots on the tool rest. After each arc, move the pivot point so that you can cut towards the outside edge of the bowl. Pulse the handle to get a good cut. If cut is too aggressive twist down and if too little, twist up to get a good contact with the surface. Once the shape is close, you can refine the cuts to remove ridges (may need to sharpen the blade at this stage).

2.        Stub base or base of bowl.

Leave a stub of about 1 inch in centre and form a slightly concave base possible with a foot to the base. Use TD at 7 O Clock (OC) and 45 degrees, use top of blade to excavate near the stub and outwards to form a slightly concave base but not very smooth because scraping rather than cutting. When shaped, move to TU tool to form a smooth surface by using tool with cutting edge to the sky. Note be very careful as the blade can easily snag.

3.       Forming foot if needed.

This is really to define the base and could be done after the outside surface is formed and the shape of the bowl is better formed. Use TD tool to cut a shoulder at the outer edge of the bottom and blend into the sides.

4.       Flatten Top.

Reverse the bowl and first flatten-off the top using TU , start at the outside and move towards the centre.  Do the usual arcing diagonally down starting at 7 OC.

5.       Making a chamfer on the rim of the bowl.

Use TU tool at 45 degrees to the rim and cut from the outside a chamfer (you are stood facing the inside of the bowl). This can be left until the inside of the bowl is carved. The chamfer can be say ½ inch wide. Need to hold tool under arm and have a tight grip including the little finger to manipulate.

6.       Inside of the bowl.

Use TD near the centre to excavate near the base of the stub (about same diameter as mandrel diameter) at 7 OC top to bottom using part of blade loop at top. The move out a little and use the lower part of the blade to cut away from the stub, i.e. with the nose of the blade facing the wood. Then use TU tool to excavate starting a little away from the dip and moving into the centre but not touching the core. Keep repeating each time starting nearer the rim and going up to the stud. Again starting at 7 OC nearer the rim and ending at 8 or 9 OC near the centre.. In between the core needs to be reduced with the TD tool flat against the core starting at the top and letting it ride down.  Use TD to deepen the base near the core. Infact you can use the TD tool to run along the entire inside of the bowl (rim to centre) with the mouth of the blade flat against the inside to start with and twisting a little to get a clean cut.

7.       Reducing the core.

 This is quite a difficult part of the carving. Up to now the core has been a continuation of the mandrel, i.e. the same diameter as the mandrel. This is particularly important with the spiked mandrel as you don’t want to hit the spikes with the chisel blade. Once below the tenon or spikes, the core needs to be reduced to less than 1 inch in diameter. I found the best method so far is to use the “Top Down” tool to reduce the main stem of the core until the metal part of the handle touches the rim of the bowl and restricts movement down the core. Then I used the same tool to excavate the bottom of the core to join the inside wall and finishing off with the TU tool to join. When the bowl is finished and it’s time to break-off the core; the trick is to reduce the core by undercutting at a point below the mandrel tenon/spikes but at the right level to continue the base without thinning the base too much or breaking through. I did this by making a channel (about 1 cm wide) with the TD tool and continuing this with the TU tool so that the cutting edge was facing the mandrel direction (i.e TU tool held upside down) basically cutting at about 6 OC until the diameter of the core was below 1 inch.

Make sure you snap off across the grain!

8.       Tool sharpening.

Basically sharpen with super-fine flat and conical diamond sharpeners. Use the conical sharpener to do the inside of the edge moving “in and out” around the edge and then do the back with the sharpener parallel to the edge so as to keep this edge flat and not curved near the cutting edge.

PS. Just to add to this after making several bowls I found it easier just to use the above techniques but play around to find my own methods that worked for me. The biggest advance is to get familiar with how the tool works and finding the best angles etc. I also found that adjusting the height of the rest bar made a big difference and getting a comfortable position for the trestle. In fact, I made another trestle that was just a piece of wood that was allowed to swing from a pivot with some uprights to control it's lateral swing. Basically, I did the outside and bottom first, interchanging between the two as the shaped developed and then started on the rim. Then I reversed the bowl and worked on the inside and rim. I always find that removing the core is difficult. Also for smaller bowls I made a smaller diameter mandrel (tenon #11, i.e. 11/16 th inches diameter) out of ash. The larger mandrel is 7/8 th inch.