wefalck

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 ...

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 ...

The original bronze spindle-nut seems to have had a left-hand thread of 4 mm x 1 mm, so it was drilled out 3.7 mm for the 4.5 mm x 1 mm thread and the thread re-cut with the appropriate tap. The odd digs and dents were removed by a light cut on both ends in the lathe.
 

Parts of the spindle and its bearings
 
A test assembly showed that everything worked as planned. The ball-handle crank has been bought-in and is fixed by set-screws, rather than being pinned as was the Lorch-practice.
 

Spindle in place, but micro-meter sleeve still to be made
 
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 ...

Some travel got into the way of progressing this project and on reporting on it ….
 
******************************
 
In order to mount the y-axis to the column, an adapter is needed. This adapter is fashioned from a small aluminium-block that was bored for the 20 mm column. The top-side was milled to a close fit on the lower slide from the WW-lathe, which is clamped down with a bolt. In this way the lower slide can be moved by about 15 mm, giving a greater depth of throat, if needed. It was planned to use a rectangular key to lock the adapter to the column. However, it appears that the two set-screws lock it sufficiently secure to the column. Practical experience will show whether this is true.
 

Drilling the adapter for the y-axis
 
The 20 mm-hole was drilled and bored on a face-plate in the lathe to ensure that it is exactly vertical to the top and bottom of the adapter block. The aluminium-block was srewed down onto the face-plate using a 6 mm hexagonal bolt. Luckily, a suitable hole was needed anyway for the locking bolt of the slide. Other hexagonal bolts prevent the block from moving during the machining operations and act as counter-weights.
 

Boring the adapter for the y-axis
 
After the functional machining was complete, the adapter was 'beautified' by giving the edges a half-round camfer. For occasional jobs on aluminium like this, I use cheap woodworking router bits ... don't tell any real mechanic.
 

Camfering the adapter for the y-axis
 

Finished adapter block
The Lorch, Schmidt & Co. milling attachment will be held between two angle-irons screwed-down onto the slide. The locking will be effected by an excentric bolt acting as a cam. I had hoped to use the threaded holes that a previous owner of the slide had made, but they did not fit the angle-iron I had in my stock, so new holes had to be drilled and tapped. The pair of angle-irons was squared and trued on the mill using a fly-cutter.
 

Squaring and trueing angle-irons in pairs
 

Angle-irons to hold milling-head
 

Angle-irons to hold milling-head
 
The above picture shows also the drive unit made for the toolpost-grinder of the WW-lathe, which in fact looks very similar to what the future motorised milling head will look like.
 

Provisional set-up of motorised milling head
 
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
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 ?

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Thanks Pat and I hope you have enough Kleenex around
 
*****************************************************************************
 
After some disruptions due to travelling (spent inter alia a couple of days in Pisa for work ) I tackled a job I had never done before:
 
Digression: making a concave knurling wheel
 
Today, concave knurls to produce the convex knurling seen on many older high-end precision machines are obtainable only at prohibitive costs. Therefore, I embarked on making my own knurl, encouraged by a few examples on the Internet. Knurling wheels normally have to have a certain diameter in order to prevent their bore from being distorted under the stress of the knurling process. I choose a blank of only 10 mm diameter for a bore of 6 mm in order to reduce the mass to be heated, when attempting to harden the knurl with my rather limited heating capabilities. I also had a cut-off from a Schaublin collet-blank available, which I assumed would harden nicely.
 

Hobbing the knurl on the milling machine
 
The proposed process of creating the knurling wheel employs an ordinary threading tap as an improvised hob. This, stricly speaking, would result in a 'rope' knurl, but the helical angle of a, say, 0.4 mm pitch tap is barely perceptible. The easiest way to hold the blank for cutting seemed to hold it in the knurling-holder for the watchmakers lathe that I made a few years ago. This means, however, that the process could not be done on the lathe, because it would have been not so easy to mount the holder on its side. Cutting the knurl on the lathe would have been better, as the end of the tap could have been supported in the tailstock in order to eliminate flexing. Unfortunaly, the DIXI horizontal mill does not have an overarm, which then would make it the ideal machine for the job. So the job was done on the vertical mill.
 

Hobbing process in detail
 
The blank was drilled and reamed for the arbor of the knurling tool holder. Some polishing ensured that it spun freely. A M2 tap was chucked in a collet as short as possible and offered to the blank with its uppermost end in order to keep flexing to a minimum. Initially, the mill was run at slow speed and with a small feed. After each incremental feed, the blank was allowed to make several revolutions until no chips were produced anymore. Once the pattern was created, the mill was run at a somewhat higher speed and the amount of incremental feed increased from around 0.03 mm to 0.05 mm. Every time blank and tap were flooded with WD40 in order to wash out the chips that then were wiped off. A first failed trial showed, how important it is to wash-out chips. The second attempt was successful.
 

The finished concave knurl
 
After the machining, the knurl was hardened by heating it to a cherry-red colour and quenching it in ice-cold water. As I don't have a very strong torch, the knurl was pre-heated to 450°C using the hot-air soldering gun and then brought to temperature with the gas-torch. The knurl was also rubbed in soap to prevent scaling. After some cleaning, the hardened knurl was tempered to a straw-yellow colour using the the hot-air gun. A test with a file showed that the hardening was successful.
The knurl in the tool-holder for the watchmakers’ lathe
 
... well, it actually worked as you will see in the next contribution
 
To be continued ...

Worked!!!

With a three day weekend coming up, I had hoped to finish the starboard side planking and painting this week.  I didn't quite make it.  I kept finding new details that I had forgotten about - like the doors.
 
Kevin's drawing shows external four paneled doors.  I went with something simpler for the internal doors that would not be seen from outside.
 
 
Cutting grooves in the door rails.  The rails are .08 inch thick with a .031 inch groove.

 

 

 
Assembling the door.

 
Hardware for the door.

 

 
Completed door.

 

 
 
The port side will be left open with only the lowest three strakes installed.  I still have a little more framing to do for the paddle box, deckhouse and outhouse.

 

 
Planking the starboard side.

 

 

 

 

 

 

This may have varied from navy to navy, but most models of the time seem to show the hammocks bent to an U-shape. The picture below shows the somewhat later BELLE POULE in the Musée de la Marine, but practices remained unchanged for some 200 years.
 

 
These rolls consisted not only of the hammock as such, but also of the associated bedding.
 
BTW, 'children caly' is neither in my mental nor printed dictionary, what is it ?
 
wefalck

Postscript:
 
Since the last posting there have been revisions! The sweeps were discovered to be sized for a single-banked boat not, as in this case, for a double-banked one. So, a new set of 12 sweeps have been made, 15' 0" as opposed to 19' 0". I also took this opportunity to paint the dolphins on one side the correct way up! Now, at the risk of incurring the wrath of the moderators, I'd like to mention that the full story, along with various techniques of making small open boats will appear in a full-color book shortly. Stay tuned!
 
Again, my thanks to all who contributed to this log. You helped to make a better model.

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.

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.

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.

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.

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.