wefalck

"I guess on the whole I'm just surprised that while you can cover a model in PE detail and someone has even come out with a credible 3D 1:350 crew, that someone like ModelExo hasn't come forward with "the thinnest, finest woven fabric on earth" or something to cater to the sail ship hobby. :)"
 
Purely for technical reasons ... you cannot weave scale cloth, neither in 1:100 or let alone in 1:350 scale. The thinnest (usable) natural fibres are the yarns taken off the cocoon of the silk worm and have 0.005 to 0.01 mm in diameter. Indidividual hemp cells have a similar diameter, but would need to be spun into a yarn to be useful. Man-made nanofibres could go down to 0.0001 mm or less in diameter, but still are prohibitively expensive.
 
In any case, the individual fibres need to be spun into yarn, the thickness of which is much greater than that of the fibres. So, I think for the moment we are stuck with the finest silk cloth. However, natural silk should be avoided in modelling, as the protein of the fibre is prone to relatively fast degradation.
 
Realistically, I think that non-woven fibrous materials, i.e. paper-like materials, are the only solution for small-scale sails. Paper can be produced from relatively short individual fibres and does not involve the mechanics of weaving, for which a long yarns are needed. Therefore, paper can be much thinner than the thinnest cloth.

"I guess on the whole I'm just surprised that while you can cover a model in PE detail and someone has even come out with a credible 3D 1:350 crew, that someone like ModelExo hasn't come forward with "the thinnest, finest woven fabric on earth" or something to cater to the sail ship hobby. :)"
 
Purely for technical reasons ... you cannot weave scale cloth, neither in 1:100 or let alone in 1:350 scale. The thinnest (usable) natural fibres are the yarns taken off the cocoon of the silk worm and have 0.005 to 0.01 mm in diameter. Indidividual hemp cells have a similar diameter, but would need to be spun into a yarn to be useful. Man-made nanofibres could go down to 0.0001 mm or less in diameter, but still are prohibitively expensive.
 
In any case, the individual fibres need to be spun into yarn, the thickness of which is much greater than that of the fibres. So, I think for the moment we are stuck with the finest silk cloth. However, natural silk should be avoided in modelling, as the protein of the fibre is prone to relatively fast degradation.
 
Realistically, I think that non-woven fibrous materials, i.e. paper-like materials, are the only solution for small-scale sails. Paper can be produced from relatively short individual fibres and does not involve the mechanics of weaving, for which a long yarns are needed. Therefore, paper can be much thinner than the thinnest cloth.

"I guess on the whole I'm just surprised that while you can cover a model in PE detail and someone has even come out with a credible 3D 1:350 crew, that someone like ModelExo hasn't come forward with "the thinnest, finest woven fabric on earth" or something to cater to the sail ship hobby. :)"
 
Purely for technical reasons ... you cannot weave scale cloth, neither in 1:100 or let alone in 1:350 scale. The thinnest (usable) natural fibres are the yarns taken off the cocoon of the silk worm and have 0.005 to 0.01 mm in diameter. Indidividual hemp cells have a similar diameter, but would need to be spun into a yarn to be useful. Man-made nanofibres could go down to 0.0001 mm or less in diameter, but still are prohibitively expensive.
 
In any case, the individual fibres need to be spun into yarn, the thickness of which is much greater than that of the fibres. So, I think for the moment we are stuck with the finest silk cloth. However, natural silk should be avoided in modelling, as the protein of the fibre is prone to relatively fast degradation.
 
Realistically, I think that non-woven fibrous materials, i.e. paper-like materials, are the only solution for small-scale sails. Paper can be produced from relatively short individual fibres and does not involve the mechanics of weaving, for which a long yarns are needed. Therefore, paper can be much thinner than the thinnest cloth.

Indeed, the bull's eye-glass (or 'Butzen' in German) has been very common and is used in 'romantic' reconstructions of medieval windows. However, considering that there only two bull's eyes coming out of each cylinder and only one from each disc, there must have been a considerable production of plate glass to give sufficient numbers of them for a window. I guess, from the mid-19th century on, they were not only 'waste' products anymore, but made specifically to meet medieval-revival demands. Also, in Germany the 'Butzen' often are 'bottle-green', indicating that inferior quality raw materials with a lot of metal contaminants were used - so the associated flat glass must have also been green.
 
Here is an image from Wikipedia that shows the production of disc-glass in the 'forest' ('en bois', because they needed the wood for fuel):

If I am not mistaken, sometime in the last quarter of the 19th century the float-glass was inventend in France, whereby the the near-liquid glass was poured onto a bassin with mercury. Indeed, France seems to have been technologically ahead in glass production for quite some time.

Following the Medieval Revival fashion in Europe from around the 1840s these 'Butzenscheiben', as they are called in German, have been used in 'restoration' and imitation projects. They have become associated with a 'romantic' view of small German towns and the likes, but can be seen in France, the UK, and other places as well.

Wasn't this blown into a long cylinder, the bottom and top disc (with the blow-pipe attachment) cut off, the cylinder split lengthwise and then rolled flat while still hot ? Cheaper and smaller panes were cut from the discs, which accounts for the streaks often seen in old window panes.

Wasn't this blown into a long cylinder, the bottom and top disc (with the blow-pipe attachment) cut off, the cylinder split lengthwise and then rolled flat while still hot ? Cheaper and smaller panes were cut from the discs, which accounts for the streaks often seen in old window panes.

I gather the problem with a lot of fancy and novelty materials is that they are (still) prohibitively expensive. They may also not be sold over the counter or in small quantities.
 
The second question would also be for what application fabrics in real life would be used that would be fine enough for modelling purposes. OK there are a lot of uses of materials the average person isn't aware of, or even wouldn't dream of.
 
Still, there are also technical limitations to the weaving of very fine materials, regardless what the thread is made of.

I gather the problem with a lot of fancy and novelty materials is that they are (still) prohibitively expensive. They may also not be sold over the counter or in small quantities.
 
The second question would also be for what application fabrics in real life would be used that would be fine enough for modelling purposes. OK there are a lot of uses of materials the average person isn't aware of, or even wouldn't dream of.
 
Still, there are also technical limitations to the weaving of very fine materials, regardless what the thread is made of.

There are a couple of basic questions to ask first:
 
- is the model made from wood or other material, namely plastics ?
 
- if it is made from wood, do you intend to keep the appearance of the real wood it is made from, or do you intend to cover it in opaque paint ?
 
There are various painting guides around the Internet for aged wood, namely in the railway and diorama modellers realms. Some use real wood as a basis and other plastics.
 
In the case of real wood, this is usually stained in some grey, controlling the process to keep perhaps some of the original wood colour. Applying white, black, and burnt umber as washings allows to modulate the basic grey. At some places a technique called 'dry-brushing' may be applied to highlight surface features.
 
On plastics, you would apply similar processes, but you would start from an undercoat of light ochre to simulate the wood.
 
Like the Old Master, in principle all the various aging or weathering effects can be achieved by painting. However, in particular the plastic modeller community has developed a range of processes that involve more or less controlled random processes, such as stripping paint layers with adhesive tape, deliberately reducing the adhesion of paint layers in order to partially strip them later to achieve a flaked impression, etc., etc. Again, there are numerous tutorials on the Web as well as in printed form available.
 
In think I pointed to some of my own work in a similar thread. This is a 'resin' modell with an ochre undercoat and various washes of burnt umber (both acrylics). In addition water/salt 'stains' were applied using white pastel chalk:
 

 

 
In the scenic setting of the above model I used real wood for the landing stage etc. that was treated with stains and acrylic washes:
 

 
I tried to give some keywords to search for in the Internet that give more detail than this short post.

I gather the problem with a lot of fancy and novelty materials is that they are (still) prohibitively expensive. They may also not be sold over the counter or in small quantities.
 
The second question would also be for what application fabrics in real life would be used that would be fine enough for modelling purposes. OK there are a lot of uses of materials the average person isn't aware of, or even wouldn't dream of.
 
Still, there are also technical limitations to the weaving of very fine materials, regardless what the thread is made of.

There are a couple of basic questions to ask first:
 
- is the model made from wood or other material, namely plastics ?
 
- if it is made from wood, do you intend to keep the appearance of the real wood it is made from, or do you intend to cover it in opaque paint ?
 
There are various painting guides around the Internet for aged wood, namely in the railway and diorama modellers realms. Some use real wood as a basis and other plastics.
 
In the case of real wood, this is usually stained in some grey, controlling the process to keep perhaps some of the original wood colour. Applying white, black, and burnt umber as washings allows to modulate the basic grey. At some places a technique called 'dry-brushing' may be applied to highlight surface features.
 
On plastics, you would apply similar processes, but you would start from an undercoat of light ochre to simulate the wood.
 
Like the Old Master, in principle all the various aging or weathering effects can be achieved by painting. However, in particular the plastic modeller community has developed a range of processes that involve more or less controlled random processes, such as stripping paint layers with adhesive tape, deliberately reducing the adhesion of paint layers in order to partially strip them later to achieve a flaked impression, etc., etc. Again, there are numerous tutorials on the Web as well as in printed form available.
 
In think I pointed to some of my own work in a similar thread. This is a 'resin' modell with an ochre undercoat and various washes of burnt umber (both acrylics). In addition water/salt 'stains' were applied using white pastel chalk:
 

 

 
In the scenic setting of the above model I used real wood for the landing stage etc. that was treated with stains and acrylic washes:
 

 
I tried to give some keywords to search for in the Internet that give more detail than this short post.

There are a couple of basic questions to ask first:
 
- is the model made from wood or other material, namely plastics ?
 
- if it is made from wood, do you intend to keep the appearance of the real wood it is made from, or do you intend to cover it in opaque paint ?
 
There are various painting guides around the Internet for aged wood, namely in the railway and diorama modellers realms. Some use real wood as a basis and other plastics.
 
In the case of real wood, this is usually stained in some grey, controlling the process to keep perhaps some of the original wood colour. Applying white, black, and burnt umber as washings allows to modulate the basic grey. At some places a technique called 'dry-brushing' may be applied to highlight surface features.
 
On plastics, you would apply similar processes, but you would start from an undercoat of light ochre to simulate the wood.
 
Like the Old Master, in principle all the various aging or weathering effects can be achieved by painting. However, in particular the plastic modeller community has developed a range of processes that involve more or less controlled random processes, such as stripping paint layers with adhesive tape, deliberately reducing the adhesion of paint layers in order to partially strip them later to achieve a flaked impression, etc., etc. Again, there are numerous tutorials on the Web as well as in printed form available.
 
In think I pointed to some of my own work in a similar thread. This is a 'resin' modell with an ochre undercoat and various washes of burnt umber (both acrylics). In addition water/salt 'stains' were applied using white pastel chalk:
 

 

 
In the scenic setting of the above model I used real wood for the landing stage etc. that was treated with stains and acrylic washes:
 

 
I tried to give some keywords to search for in the Internet that give more detail than this short post.

The blank on its arbor was then transfered to the dividing apparatus on the milling machine for engraving the dial. For this a 15° engraving bit was used. in the same set-up the hole for the friction brake of the dial was pre-drilled.
 

Set-up for engraving the dial
 

Engraving the dial
 
The numbers were stamped in a make-shift set-up in a vice. In order to ensure that the number-stamps were applied exactly radially a purpuse-made guide-block was used.

Set-up for stamping the dial
 
Finally, the dial was mounted back on the arbor and the burrs from engraving and stamping cleaned up with a couple of light cuts in the lathe.
 

Cleaning up the engraved and stamped dial
 
The two parts were separated on the lathe with a jewelers saw substituting for a parting tool. The dial then was degreased and the engravings laid out in black enamel paint. After the generously applied paint had dried, the dial was cleaned up with very fine wet-and-dry sanding paper.
 

Painting the dial
 
To be continued ...

The blank on its arbor was then transfered to the dividing apparatus on the milling machine for engraving the dial. For this a 15° engraving bit was used. in the same set-up the hole for the friction brake of the dial was pre-drilled.
 

Set-up for engraving the dial
 

Engraving the dial
 
The numbers were stamped in a make-shift set-up in a vice. In order to ensure that the number-stamps were applied exactly radially a purpuse-made guide-block was used.

Set-up for stamping the dial
 
Finally, the dial was mounted back on the arbor and the burrs from engraving and stamping cleaned up with a couple of light cuts in the lathe.
 

Cleaning up the engraved and stamped dial
 
The two parts were separated on the lathe with a jewelers saw substituting for a parting tool. The dial then was degreased and the engravings laid out in black enamel paint. After the generously applied paint had dried, the dial was cleaned up with very fine wet-and-dry sanding paper.
 

Painting the dial
 
To be continued ...

Per, as it never was, the mill doesn't have a price-tag   ... unless you were indeed prepared to pay me at my commercial rates, which means that you would have to trade-in a decent car, may not quite an Aston Martin (but I would gladly exchange it for the mill, BTW)
 
***********************************
 
For the dial on the y-slide I had a piece of 21 mm diameter brass to hand. This was faced in the 3-jaw-chuck, drilled and reamed for the 5 mm spindle, and then bored out to fit over the spindle bearing-plate.
 

Preparing the blank for the dial
 
The blank was the mounted on an arbor with a 5 mm stem so that I could turn the outside shape. At one end there is the notorious convex knurled ring. For this, a ring of 1.2 mm width and 1 mm height was left standing with edges slightly chamfered.
 

Turning the blank for the dial
 
For the next machining step the knurling tool with the concave knurl was mounted to the cross-slide. The knurling tool was fed slowly into the slowly rotating blank. It catches quite quickly at the edges and the pattern evolves fast. As expected, the processes is both, a cutting as well as a shaping one – the relatively soft being squeezed into the indentations of the knurling wheel. While generously lubricating with WD40 the knurl was fed into the faster rotating blank until the pattern had developed fully.
 

Knurling the dial
 
To be continued ...

The blank on its arbor was then transfered to the dividing apparatus on the milling machine for engraving the dial. For this a 15° engraving bit was used. in the same set-up the hole for the friction brake of the dial was pre-drilled.
 

Set-up for engraving the dial
 

Engraving the dial
 
The numbers were stamped in a make-shift set-up in a vice. In order to ensure that the number-stamps were applied exactly radially a purpuse-made guide-block was used.

Set-up for stamping the dial
 
Finally, the dial was mounted back on the arbor and the burrs from engraving and stamping cleaned up with a couple of light cuts in the lathe.
 

Cleaning up the engraved and stamped dial
 
The two parts were separated on the lathe with a jewelers saw substituting for a parting tool. The dial then was degreased and the engravings laid out in black enamel paint. After the generously applied paint had dried, the dial was cleaned up with very fine wet-and-dry sanding paper.
 

Painting the dial
 
To be continued ...

Actually, I wanted to continue with my SMS WESPE model, but run into some technical difficulties and then this project came my way ...
 
The complex manual machining of very small parts on a milling machine requires smooth and precise movements of the slides as well as small masses to be moved. The slides of a watchmakers lathe fulfill these requirements. In addition, work-pieces and tools should be visible very well during machining.
 
Milling machines such as the Aciere F1 (or the older F12) or Sixis 101 are ideal for working on small parts, but are still far too large for my workshop (and have a too big price tag ...). Interesting from a design point of view would be also jig-borer and milling-machines by SIP (Société Genevoise d'Instruments de Physique), but they are very rare and difficult to come by. All these machines are massive and heavily constructed in order minimise vibrations by their inertia during the machining of precision parts for watches and instruments – too massive for my small workshop.
 

Aciera F1 milling machine (Source: http://www.lathes.co.uk/aciera/)
 

Sixis 101 milling machine (Source: http://www.lathes.co.uk/sixis/)
 

SIP jig-borer and milling machine  (Quelle: http://www.lathes.co.uk/sip/)
 
A special feature of these machines is that the x-slide is not arranged horizontally under the milling spindle, but vertically in front of the main column. This permits the easy installation of a fourth and fifth machining axis.  However, this arrangement means that the movement in the y-axis is not effected by the cross-slide, but by the milling head. This in turn means that milling head and motor should ideally form a unit. A belt-drive is more difficult to arrange, because the angle between the pulleys changes, when the milling head moves along. The SIP jig-borer for these reason originally was driven through a flexible shaft.
A watchmakers lathe is a good starting point owing to the precision of the slides and spindles, but it lacks the z-axis. In more recent years kits became available to convert Chinese-made watchmakers lathes into small vertical milling machines, but the milling table on them is arranged in a conventional way.
 

Conversion of a modern Chinese watchmakers lathe into a vertical milling machine
 
In my stock of watchmakers lathe bits and pieces I have collected over the years parts for several D-bed lathes of variable state of conservation. Some ‘scrap’ was also bought on purpose. From this parts I now want to construct a micro-milling machine with as little work as possible.
As design specifications I decided that the mill should be able to machine in a space of u 20 mm x 20 mm x 20 mm. This requires movements along the x-, y-, and z-axes of around 40 mm. There should be a fourth axis with a 360° rotation, that should be able to rotated under load. This axis should also be able to be moved from the vertical into the horizontal (5th axis). All those movements should be realised with parts from watchmakers lathes, so that no dove-tail slides need to be machined from scratch.
The back-bone of the mill will be a special D-bed that I obtained recently. It was originally meant for the conversion of a lathe into a small precision pillar-drill. Its lower end is turned down to a diameter that fits into a lathe foot. The foot that I am going to use probably came from a British Pultra-lathe (http://www.lathes.co.uk/pultra/page8.html).
 

Column and foot
 
Another key part is an old and somewhat battered cross-slide from a Lorch, Schmidt & Co. D-bed lathe. This will be the x- and z-axis of the new milling machine.
 
Cross-slide from a D-bed watchmakers lathe
 
The y-axis will be constructed with the help of a nearly scrap lower-slide from the cross-slide of a Lorch, Schmidt & Co. WW-lathe that I was able to buy cheaply. The spindle and micrometer-dial will have to be made from scratch. A 6 mm-grinding spindle of unknown make will serve as milling spindle. This limits somewhat the maximum diameter of cutters that can be used to ones with about a 4 mm-shaft, but the machine is meant for light work after all. On the other hand, many years ago I made an adapter for 6 mm end-mill for use in the lathe together with a vertical slide (before I owned a milling machine).
 

Lower slide from a WW-lathe cross-slide and grinding spindle
 

Future arrangement for the y-axis of the micro-mill
 
The fourth and fifth axis will be formed by the dividing head that I made some years ago from a 6 mm-watchmakers lathe grinding-spindle. For the moment it will be simply screwed onto the cross-slide as for use with a lathe. This gives considerable flexibility for the positioning at any angle between vertical and horizontal. The setting will be a bit time-consuming and has to be done with templates.
 

Column, cross-slide and dividing head assembled
 

Column, cross-slide and dividing head assembled
 
So far the existing parts that need to be re-conditioned somewhat at a later point in time.
 
To be continued ...

The blank on its arbor was then transfered to the dividing apparatus on the milling machine for engraving the dial. For this a 15° engraving bit was used. in the same set-up the hole for the friction brake of the dial was pre-drilled.
 

Set-up for engraving the dial
 

Engraving the dial
 
The numbers were stamped in a make-shift set-up in a vice. In order to ensure that the number-stamps were applied exactly radially a purpuse-made guide-block was used.

Set-up for stamping the dial
 
Finally, the dial was mounted back on the arbor and the burrs from engraving and stamping cleaned up with a couple of light cuts in the lathe.
 

Cleaning up the engraved and stamped dial
 
The two parts were separated on the lathe with a jewelers saw substituting for a parting tool. The dial then was degreased and the engravings laid out in black enamel paint. After the generously applied paint had dried, the dial was cleaned up with very fine wet-and-dry sanding paper.
 

Painting the dial
 
To be continued ...

While sorting out the replacement motor for the mill, I turned my attention to making the spindle for the y-axis. Most WW-lathes seem to have the odd thread of 4.5 mm x 1 mm pitch. The spindles from the old cross-slide I am using were missing, but must have been thinner, probably 4 mm. As I have both, a die and a tap for the usual left-hand thread, I decided to adapt the cross-slide for this.
 

 

Set-up for cutting the thread on the y-axis spindle
 
 
First the spindle was made. Unlike the original desing on watchmakers’ lathes, it will have two ball-races as thrust bearings, but otherwise the design will be similar. The ball-handle crank is a commercial product. I started out with a 5 mm rod and turned it down to 4.5 mm and then set-up the lathe for cutting the left-hand thread.
 

The first pass
 

Almost finished spindle
 
This means cutting proceeds towards the tailstock. As the torque on the WW-lathe transmission system is too low, the thread was cut by hand-cranking. For this purpose I had made an adapter for a ball-handle crank already a long time ago. The thread was cut with full cuts until it was about 90% complete.
 

Calibrating the thread using a 4.5 mm x 1 mm die in the tailstock
 
The final cut then was made with a die in the tailstock die-holder to calibrate the diameter, which might have been a bit bigger in the middle due to the flexing of the long spindle. In order to eliminate the effect of flexing, the cutting bit was run along the thread several times without adavancing it into the work, until no material was taken off anymore.
 

The finished spindle thread
 
To be continued ...

Thanks, Pat. I was actually surprised myself, that it turned out so well

Per, as it never was, the mill doesn't have a price-tag   ... unless you were indeed prepared to pay me at my commercial rates, which means that you would have to trade-in a decent car, may not quite an Aston Martin (but I would gladly exchange it for the mill, BTW)
 
***********************************
 
For the dial on the y-slide I had a piece of 21 mm diameter brass to hand. This was faced in the 3-jaw-chuck, drilled and reamed for the 5 mm spindle, and then bored out to fit over the spindle bearing-plate.
 

Preparing the blank for the dial
 
The blank was the mounted on an arbor with a 5 mm stem so that I could turn the outside shape. At one end there is the notorious convex knurled ring. For this, a ring of 1.2 mm width and 1 mm height was left standing with edges slightly chamfered.
 

Turning the blank for the dial
 
For the next machining step the knurling tool with the concave knurl was mounted to the cross-slide. The knurling tool was fed slowly into the slowly rotating blank. It catches quite quickly at the edges and the pattern evolves fast. As expected, the processes is both, a cutting as well as a shaping one – the relatively soft being squeezed into the indentations of the knurling wheel. While generously lubricating with WD40 the knurl was fed into the faster rotating blank until the pattern had developed fully.
 

Knurling the dial
 
To be continued ...

What lathe do you have ? It may be worthwhile to invest into collets, if your lathe spindle has a taper for them, or into a collet chuck. This gives a much better and concentric grip on thin material - and is also safer, because you are not bothered by the jaws and can work closer to the chuck, which eliminates chatter.
 
Of course, the tailstock needs to be checked for alignment.
 
Why do you use a file to make the groove ? A tool in the slide rest would be safer and more efficient - or are you using a wood lathe ?

Per, as it never was, the mill doesn't have a price-tag   ... unless you were indeed prepared to pay me at my commercial rates, which means that you would have to trade-in a decent car, may not quite an Aston Martin (but I would gladly exchange it for the mill, BTW)
 
***********************************
 
For the dial on the y-slide I had a piece of 21 mm diameter brass to hand. This was faced in the 3-jaw-chuck, drilled and reamed for the 5 mm spindle, and then bored out to fit over the spindle bearing-plate.
 

Preparing the blank for the dial
 
The blank was the mounted on an arbor with a 5 mm stem so that I could turn the outside shape. At one end there is the notorious convex knurled ring. For this, a ring of 1.2 mm width and 1 mm height was left standing with edges slightly chamfered.
 

Turning the blank for the dial
 
For the next machining step the knurling tool with the concave knurl was mounted to the cross-slide. The knurling tool was fed slowly into the slowly rotating blank. It catches quite quickly at the edges and the pattern evolves fast. As expected, the processes is both, a cutting as well as a shaping one – the relatively soft being squeezed into the indentations of the knurling wheel. While generously lubricating with WD40 the knurl was fed into the faster rotating blank until the pattern had developed fully.
 

Knurling the dial
 
To be continued ...

Per, as it never was, the mill doesn't have a price-tag   ... unless you were indeed prepared to pay me at my commercial rates, which means that you would have to trade-in a decent car, may not quite an Aston Martin (but I would gladly exchange it for the mill, BTW)
 
***********************************
 
For the dial on the y-slide I had a piece of 21 mm diameter brass to hand. This was faced in the 3-jaw-chuck, drilled and reamed for the 5 mm spindle, and then bored out to fit over the spindle bearing-plate.
 

Preparing the blank for the dial
 
The blank was the mounted on an arbor with a 5 mm stem so that I could turn the outside shape. At one end there is the notorious convex knurled ring. For this, a ring of 1.2 mm width and 1 mm height was left standing with edges slightly chamfered.
 

Turning the blank for the dial
 
For the next machining step the knurling tool with the concave knurl was mounted to the cross-slide. The knurling tool was fed slowly into the slowly rotating blank. It catches quite quickly at the edges and the pattern evolves fast. As expected, the processes is both, a cutting as well as a shaping one – the relatively soft being squeezed into the indentations of the knurling wheel. While generously lubricating with WD40 the knurl was fed into the faster rotating blank until the pattern had developed fully.
 

Knurling the dial
 
To be continued ...