johnsmachines

machines which I have made, am making, or intend to make, and some other stuff. If you find this site interesting, please leave a comment.

Category: Other stuff

Swap Meet Bargains

Yesterday I travelled to Ballarat, (Victoria, Australia) to a swap meet which was held on 22 acres at the airfield.

Most of the stuff in the thousands of sites, was junk from shed and farm cleanouts.  However, despite rapidly walking up and down the rows, I did not quite cover all of the sites.  My Apple watch indicated that I had walked 18km (11.2 miles) and much of that was carrying a backpack full of bought items, so it was no wonder that my ankles were aching at the end of it.

I was really only interested in the few sites which had tools from factory closures.  But my eye was drawn to the very old Caterpillar crawler tractor, a 2 tonner, not too derelict except for a broken exhaust manifold and some rusted growsers.  $AUD9500, so I kept on walking.   Lots of elderly, old and antique cars, motor bikes, and vehicular bits and pieces.

The following photos show most of the stuff which I bought, and some prices (except for the ones which SWMBO must never discover).

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A Japanese woodworker’s chisel.  9 mm wide.  Razer sharp, oak handle.  I buy one of these at each Ballarat swap meet from the same seller, a lovely Japanese woodworker who lives and works in Victoria.  These chisels are a pleasure to use.  $AUD25

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This was a bargain.  A set of good quality English BA open ender spanners, probably unused, for $AUD8

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I dont know what this is called, but it has an INT40 taper, and bolts to the workbench or mill for inserting and removing cutters from the toolholholder, and avoiding the cutter dropping down and being damaged.  Is it a tool setter?  Anyway, $AUD40

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Used but sharp, quality brands.  Carbide ball nose end mill, countersink bit, T slot cutter, and 1/4″ BSP spiral tap. $AUD30

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A new, interesting woodworking cutter, carbide, with left and right hand spirals to avoid surface furring.  $AUD10

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3 Mitutoyo telescoping gauges.  $AUD10

I mulled over a Mitutoyo 1000mm vernier caliper in perfect condition for $AUD300, but decided that it was a wanted rather than needed item, and walked on.

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A box of 12 brand new quality Wiltshire triangular files. $AUD12

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2 very nice Moore and Wright thread gauges, which have BA and Acme threads as well as metric and Imperial angles.  $AUD6

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A box of metric counterbores.  Not cheap, but good price considering the German quality, and condition.  $AUD55

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Small die holder, Sidchrome 10mm spanner, tiny Dowidatadjuster and new box of inserts.  All useful.  About $AUD45

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Chesterman vernier height gauge.  Unusual triangular column. Beautiful condition, complete range of accessories, in a lined box.  Metric and Imperial.  Price not to be dislosed to SWMBO.

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These are brass wick type oilers which I will give to the local Vintage Machinery Society.  No markings.

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My brother was a navigator in the Australian Air Force many years ago, before the age of satellite navigation.  He would sight the stars using a sextant something like this to calculate the plane’s position, while standing in a glass dome in the roof of the aircraft.  (I think that I got that description approximately correct).   He once told me that he would like to have a sextant again, so when I spotted this at the swap meet, and the price was OK, I decided to get it for him.  Maybe it will make up for all of those forgotten birthdays.  So little brother, leave some room in your suitcase when you next visit.  I will leave the clean up and renovation to you.

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Elliott Bros London.

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It looks fairly complete and intact.  Of course I have no idea how it works.

Turkish Bombard – the barrel mouth

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Except for a name plate I have finshed the bombard.  The floral design at 12, 4 and 8 is not as clear as I wished, and the Arabic script at 2, 6 and 10 is even worse.  But it is cut in wood, and it is a first effort at such work, and it is not easily seen in a model only 106mm 4.2″ diameter, so I am reasonably satisfied.

Also, this was always a prototype, in wood, and I have not totally dismissed the idea of making it in cast iron or brass.  In metal I am sure that the detail work would be a lot finer.

Turkish Bombard. The Barrel Script

Well, I bought a pair of NSK bearings for the Z axis of my CNC mill, and removed the old ones and inserted the new ones.  Cost $AUD 200.  Plus 2 or 3 half  days of  dirty heavy work.    And the problem persisted!!@!@

OK.  Time to get an expert opinion.  Here comes the cavalry.  Thank goodness for my expert friend Stuart T.

Very puzzling.  Even for Stuart.  There was some unwanted movement in the Z axis (about 2mm), despite being apparently properly installed.  Not a problem with the ballscrew or ballnut.  Even Stuart was puzzled.

“have you got any left over bits and pieces?  Is it all installed the way it was before?”

To cut the story short, we installed a thicker washer below the locknuts, and it seemed the problem was fixed.  Or was it?

Today I did another test run of the bombard mouth Arabic script.  Worked fine.  OK.  Time to finish the bombard.

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Here is the finished result, ready for painting.  I have used a 20 degree engraving carbide bit with a 0.2mm flat end.  There is some loss of fine detail but it is I think, adequate.  When it is painted, the filling putty above the pin screws (the white circles) will be invisible.  The engraving took a total of about 60 minutes, at 500mm/minute, 15,000 rpm.

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The setup.   A large angle plate clamped to the table.  The work clamped to the angle plate.

The translation of the Arabic script is “Help O God the Sultan Mehmet Khan son of Murad. The work of Munir Ali in the month of Rejeb. In the year 868.”

Turkish Bombard. The Arabic Script.

A little unfinished business on my model bombard is the Arabic script and floral decoration around the barrel mouth.

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XIX.164 / 19-00164 Detail of muzzle of a great bronze gun. Turkish, dated 1464 Royal Armouries Museum, Leeds LS10 1LT Transparency tr-1185 Imacon Flextight Precision II

This is what I have managed so far….

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It is a practice run in scrap wood.

Some of the detail has disappeared because I used a milling cutter with an end width of 0.5mm.  Next time I will add another step using a cutter with a sharp point, and a lot more of the fine detail will appear.

That pattern took a total of 80 minutes to CNC mill, with the feed rate set at 500 mm/min.

Unfortunately my CNC mill developed a problem with the Z axis, probably due to a worn out end bearing.  I am hoping that it is not the ball screw nut.  Now in the process of removing the bearing. A heavy, awkward, dirty job.

When the mill is working again I will mill the actual bombard model and post some pics.

Computer graphics is not my strong point.  To get the CNC mill to cut that pattern I did the following..

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  1. Enlarged the photo, outlined the tracery and the script, then traced the outline onto tracing paper.  That 550 year old pattern is worn and hard to define in many places.  Quite a bit of guess work.  Lucky that almost no-one can read ancient Arabic script these days.
  2. Scanned the tracing and loaded the scan into Corel Draw
  3. Used Corel Draw to smooth the curves, and make 3 copies in an array of the floral design
  4. Converted the drawing to bitmap file (bmp)
  5. Used V Carve Pro to convert the bmp file to vectors
  6. Used V Carve Pro to generate the CNC G codes
  7. CNC milled the scrap wood at 16000rpm, using a 3.2mm carbide cutter

After the triple

I am back onto the triple expansion steam engine, after putting it aside for most of 2016.  I am guessing that it is about 75% completed.  I have been struggling with this project due to poor plans, no instructions and some lack of skill and knowledge.

When I was well into the project, a colleague pointed out that detailed instructions existed in some articles published in 1985 (Model Engineer, Bertinat).  I obtained the articles, and subsequent progress has been greatly assisted, but unfortunately some errors had already crept into my work, and these have not been easily or completely rectified.

So now I am back into it.  And I would hope to have it finished and working by the end of the year.  Watch for pictures when there is something to show.

I am already thinking about what will follow the triple.  Maybe a Harrison 1 clock? (of “Longitude” fame.)  Looking for some plans.

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Or maybe some more artillery?  How about a working  model  trebuchet?  Now that does have some appeal.  There are some plans on the Net, but they look over simplistic.  I am thinking of a more historically accurate model.  The following picture is from an old French encyclopaedia.  But I might have to abandon my preferred scale of 1:10 because the original was about 12 meters long.  But on the other hand……

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It does have some interesting features.  The ratcheted windlass, the travelling pulley, the trigger mechanism (“pulling the pin”), and the projectile release mechanism (trying to avoid the projectile going up vertically).

 

Model Ottoman Bombard – Painting

I would have preferred that the title of this blog was “Finishing the Ottoman Bombard”, but I am still waiting for the vectors of the barrel mouth decorations and Arabic (?) writing, and the touch hole.

But I have at least painted the bombard, and the pictures follow.  You will notice that I have not attempted to reproduce the bronze or copper colours of the orginal in Fort Nelson.  Partly because I doubted my ability to make painting such variegated patterns realistic, and partly because the cannon would not have looked like that in its heyday of 1464.  It would probably have been either black, like most SBML cannons (smooth bore muzzle loading), or possibly gaudy golds and reds and blues like other medieval items.  So I painted it black.  I like it.  If I get evidence that it should be more colourful I can change it later.

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First coat – Primer.  Hmmm… interesting colour.

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Next coat – matt black brushed on, to fill the hairline wood cracks.  Incidentally, the (dirty) parquetry floor is also made from the red gum house stumps from which the cannon is made.

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final two coats –  matt black, from a spray can. 

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So there it is, finished except for the barrel mouth engraving, and the touch hole.  Now what to do with it…   SWMBO says it might be useful as an umbrella stand.

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The breech.  25mm diameter explosion chamber.  1:10 scale

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The barrel, 63mm bore.

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Assembled.  The model is 520mm long.

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It does need some decoration

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Ottoman Bombard Photo to Vector

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This is the low res photo from Fort Nelson.  High res photo on its way.

In the meantime, I have contracted with a US firm to convert the picture to vectors.  More $US.  ($US50 to be exact).

I am not sure that this is going to work.  But I will report to you.

I do wonder what that the Arabic/Turkish writing means.  Does anyone know?  I am pretty sure  that it is not complimentary to Christians/Westerners/Non Muslims.  Maybe it is just an instruction not to look before the touch hole is touched.  Or “do not stand here”.

PS.  Note added 17 Oct 2016.    The translation is   “Help O God the Sultan Mehmet Khan son of Murad.  The work of Munir Ali in the month of Rejeb.  In the year 868.”

868 = 1464 ce.

 

TURKISH BOMBARD- HELP!

Does anyone have a decent photograph of the writing on the muzzle?

I have repeatedly hunted through every picture which I can find on the net, but they are either taken at an angle, or too poor quality to be useable.

Does anyone have a photograph which I could beg buy or borrow?

I also need a photo of the touch hole.

I have contacted the Fort Nelson Armoury Museum, but not too surprisingly there was no response.

Is there someone in the Portsmouth UK area who could pop in and take some pics for me?

POSTSCRIPT:  October 5.   I have had 2 excellent and positive responses to my appeal.

First, reader Richard sent me a connection to a Turkish Dr/Professor, who has made a 1:25 model of the bombard using 3D printing.  (at least that is how I think he has done it.  My Turkish is non existent).  I am following this lead.

Secondly I have had a response from Fort Nelson Armoury, with a good photo of the barrel mouth, and a high res photo on the way, after payment of a significant, but not unreasonable fee.  Isn’t the Internet wonderful!!

 

TURKISH BOMBARD – the real thing

I have found this video to be particularly useful in my modelling of the Ottoman bombard. The subject of this video is the gun that the Turkish sultan gifted to Queen Victoria when the Brits and the Turks were allies.  It might be one of the guns which fired on the British fleet in 1807, when it (the gun) was 343 years old!

Notice the colour.  It is aged bronze.  I am thinking about how to reproduce that colour on my model.

 

Length of the assembled gun 5.2m (17′)

Bore 635mm

Breech weight 8942kg

Barrel weight 8128kg

Average weight of shot 307kg

the model is at a scale of 1:10.  photos soon.  being painted.

 

Modelling A Turkish Bombard- The Pins

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There are 16 pins at each end of each section of the cannon.

These were certainly used as leverage points, for very strong men with large levers to rotate the 8-9  tonne segments against each other to engage and tighten the screw.

I cannot see how the pins would have been cast with the breech and barrel.  For my model I decided to make separate pins and fit them into the gap between the big rings, then insert a grub screw through both rings and the pin.  The holes are then filled.

I wonder if a similar method was used in 1464.  I would love to have a close look at the original cannon to figure this out.  From the photographs, I can see no evidence of later insertion of pins, but neither can I see how it would have been done any other way.

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Drilling the holes for the grub screws

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In order to continue with red gum, I made my own pins.  This is the setup.  The blank is held approximately centre in a 4 jaw….

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…and the pins are turned, centre drilled, drilled, cut to length,  and tapped M4.  64 altogether.

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The M4 x 25mm grubscrew is screwed into the pin.  The wood join is super glued.  Also, I am attempting to patch the worst of the thread tearouts.

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Using a battery screwdriver to insert the grub screws.  The pins protrude above the ring surface for a reason..

 

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Sanding the pins flush with the rings.  Check the photo of the original 1464 model.  There is also some wood filler in other splits.  Not surprising after holding up a house for 70 years.

The holes are now filled with wood filler, and will be sanded flush.  They should be invisible after painting.

Next the painting, the stands, and some cannon balls.  How to reproduce that aged copper colour…

 

Modelling a Turkish Bombard -4 Decoration

The decoration around the barrel is formed by a repeating pattern, which when milled, very cleverly forms 2 identical patterns.  One is excavated and one is the original barrel surface.  You will see what I mean if you look at the pictures in the earlier blog, and the video below.

It took me an evening of experimenting on the computer to work out the system and draw it.

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Then I measured the diameters of the 2 gun components, calculated the circumference, (OK it is not rocket science.   3.142 times diameter), then working out the number of identical shapes which would fit around the 2 different diameters, at the same size and spacing.   Amazingly, it took 18 shapes to fit almost exactly around the barrel, and 16 of identical size almost exactly around the breech.  the angular spacing was 20 degrees and 22.5 degrees.

Then the shape was imported into V-Carve Pro, and G codes were generated.

My CNC mill does not have a 4th axis, so I used a dividing head to move the workpiece at the precise angles.  See the setup in the video.  That meant that the pattern was engraved into 16 and 18 flat surfaces, rather than a continuous cylinder as on the original.

It worked very well.  There were minor compromises due to the shapes being milled with a fine end mill but when you look at the pics I hope that you will agree that it is effective.

I calculated that the milling had to be at a maximum depth of 2mm in order to cope with the curvature, but if I do it again,  I would reduce the depth by 25%.

The first part of the video is a shot of CNC drilling.  Then the CNC routing of the repeating patterns.  Each angular setting of the pattern took 4 minutes to complete.  136 minutes altogether.  In reality, it took a whole day, most of which was spent doing the setups.

 

 

Bombard Model-3 turning the barrel

Another session or two, and this project is complete.

Now how do I make a cannon ball 62-63 mm diameter?  In wood will be ok?  Does not have to be granite.  I could make a mould and cast it in aluminium or lead, but stone would be authentic…..   thinking.

ps.  Re cannon balls.  I will cast them, in cement!   Now, how to make a mould.

Bombard Model -2. Big Thread

The breech and the barrel are joined with a very large thread.  On my 1:10 scale model it is 60mm diameter, and has a pitch of 6 mm.  These dimensions are measured off Internet photos of the original bombard, so they might not be faithfully accurate to the original bombard.  If anyone has accurate plans of the bombard I would be very interested to hear from them.

I experimented with various spindle speeds, feed rates, depth of cut, and finally decided that red gum wood is not the ideal material to be cutting a thread with sharp points.  However, at 200rpm, and taking 50 cuts to reach the full depth, and using a very sharp tool, the end result was OK.  I will fill the tearouts.

In order to make a functional join in the wooden cannon, I truncated the apex of the thread.  In the gunmetal version I will attempt a more faithful to the original, sharp look.

For some reason, the wood held together better during the internal thread cutting than the external.

 

The male thread was cut on my newly CNC converted lathe,  between centres, but the fixed steady on that lathe was just too small to hold the barrel, so the internal thread was cut on my bigger Chinese lathe.

Next I will bore the barrel to 63mm, then turn the exterior of the barrel.

 

Turkish Bombard 1:10 scale

Just for fun I will use my newly converted CNC lathe to make a 1:10 bombard.  The original was cast in 1464 and was thought to be a close copy of the bombards which Mehmet 2 (“the conqueror”) used to breach the walls of Constantinople in 1453.  There are several of these bombards still in existence, including one in UK, which was given to Queen Victoria by the then Turkish Sultan.

These bombards were last used, against the British, in 1807, when a British warship was holed with substantial loss of life.  Pretty amazing for a 340 year old weapon.

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5.2 meters long, 1.060 meter diameter. 16.8 tonnes.

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The large thread connected the halves.  Easier transportation, and casting.

 

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Is this Turkish or Arabic?

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Granite balls are 630mm diameter.

 

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A reconstruction of the walls of Constantinople, with moat.  Almost 1000 years old in 1453  

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And as they are today.  Massive.  High.

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Huge siege cannon used in the final assault and fall of Constantinople in 1453. Diorama in Askeri Museum, Istanbul, Turkey.  The bombards were probably dug in, to manage the massive recoil, and concentrate the aim at a particular wall section.  There is a wooden structure built around the cannon in the background of this modern picture.  As far as I know there are no surviving  wooden structures like this.  Nor have I come across any old pictures, but if anyone knows of any I would be very interested.  The bombards took about 3 hours to cool, cleanout and reload.  

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My model will be about 520mm long.  I would like to make it from bronze, or gunmetal as in the original.  Any mistakes will be costly.

So I have decided to make a prototype in wood.  That will test my drawing, the machining procedure, and the final appearance.  Not to mention how the CNC lathe will handle the task.

I will use a very dense, tight grained Australian hardwood (red gum).  The wood was salvaged when my house stumps were replaced with concrete.  Some was used to make parquetry, and the rest was put aside for possible future use.  Such as this.

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About to cut off the below ground section of a 70 year old house stump.

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A 5hp metal lathe with a tungsten bit chomps through the hard dry wood.

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I turned 6 lengths before I found 2 that were satisfactory.  The rest had sap holes or splits.

I have used Ezilathe to generate the G codes.

to be continued….

 

A Matter of Scale

Before I get onto a brief reflection about scale, the photo below shows 2 cannon barrels.

The big one was what impelled me to converting a manual lathe into a CNC lathe.  That time consuming, costly, and ultimately very satisfying project, started because the CNC lathe which I used to turn the big barrel could only handle the job by doing it in two stages…. doing the breech first then the muzzle.  That was due to the big barrel being too long for the lathe, at 300mm (12″).

The small barrel was a test for the CNC converted lathe just finished, being the first complicated shape which I have made.   To save on material, I made it at exactly half the scale of the big one, ie 150mm long (6″).

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Comparing the two barrels reminded me, that if an object is twice as big as another, in all 3 dimensions (height, width, depth), it is 8 times as heavy.   And any projectile, and weight of black powder, would also be 8 times the weight.  But the wall thickness of the explosion chamber is only TWICE as thick.

My point is, that if scale is maintained, the smaller the cannon, steam engine, boiler, whatever…..  the less likely it is to explode.

Not that these cannons will ever be fired.  Just hypothetically.

Steam Engine Oilers

Knowing that I have an interest in CNC machining, Tom, from the Vintage Machinery Club in Geelong asked me to make a pair of oilers for a very old Wedlake and Dendy steam engine.  The engine is a large (to me anyway) stationary engine, which is run on steam several times each year.  The oilers for the cross slides were missing.

We searched the Internet for pictures of W&D steam engines, but could find no pictures or diagrams of the oilers.  So Tom sketched a design, and I drew a CAD diagram.  The dimensions were finally determined by the materials which I had available…  some 1.5″ brass rod and some 1.5″ copper tube.

This is the almost finished product.

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Just needs 1/4″ BSPT fittings and and oil wick tube so they can be fitted to the engine.

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The copper tube silver soldered to the brass cylinders (top), the brass blanks for the lids (bottom) and the mandrel to hold the assembly (bottom centre) during CNC turning and drilling.

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The mandrel to hold the body (left) and the mandrel for the lid (right).  The cap screw head and hole in the mandrel have a 2 degree taper.  The slits were cut with a 1mm thick friction blade.

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Rough turning the base.

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Turning the lid.  The mandrel is held in an ER32 collet chuck

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Engraving the lid.  Using a mister for cooling and lubrication.  16000rpm, 200mm/min, 90 degree TC engraving cutter.

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The oilers work by wicking the oil from the reservoir into a tube which drains through the base onto the engine slide.  When the wick tubes are fitted the oilers can be fitted to the engine.

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The 1865 Wedlake and Dendy

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My lathe is a Boxford TCL125, using Mach3.  The G code is generated using Ezilathe.

Below is a link to an oil cup from “USS Monitor”, of American civil war fame.   One of the first ironclads, powered only by steam.

http://www.marinersmuseum.org/blog/2010/04/one-oil-cup-down/

(ps. The  lathe which I was converting to CNC was the subject of previous posts and is now working, but needs some guards fitted and a bit of fine tuning.)

MORE ANCIENT GREEK TECHNOLOGY, THE ANTIKYTHERA MECHANISM

This mechanism was discovered in 1901, in a Roman era shipwreck, off the Greek island of Antikythera, which is a bit north of Crete.

It has been dated to between 100BCE and 205BCE, with the older date considered the best estimate.  ie, about 2200 years old.  Experts believe that its makers were Greek.

It is currently housed in the Greek National Archeological Museum in Athens.

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Not much at first glance, but when it was examined with modern scanning and X ray techniques…

Look it up on Wikipedia..

https://en.wikipedia.org/wiki/Antikythera_mechanism

According to the Wikipedia entry the gear teeth are too irregular to have been machine cut,

but watch the computer reconstruction.   Could you make this machine without a lathe and gear cutters?

How much more technology did the ancients have that has not survived the ravages of time?   A lathe for example.

ANCIENT GREEK MACHINING

I recently had a light globe switched on in my brain.

I was holidaying in Athens (the one in Greece), and was gobsmacked by the huge, fabulous collection of statues, mosaics, ceramics, gold jewellery and masks, bronze and iron weapons in the National Archeological Museum.   I took many photos, and might post some in later blogs.

Three items sent shivers down my spine.

  1. The gold death mask of Agamemnon (probably not Agamemnon’s but that is another story).
  2. The Antikythera machine.   More about that in a future post.
  3. A gynaecological speculum.

There was a display with many surgical instruments.  These have been found at various archeological digs in Greece, and while not precisely dated (at least not labelled) they are mostly from 500-200 BCE.

My eye was immediately drawn to an instrument which looked very familiar.  I was a gynaecologist in my previous life, and this could have come from my instruments. (except that the dark bronze surface might not have been acceptable to patients).

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Not a great photo, through a glass cover, and ISO cranked up to several thousand.

The instrument is labelled a vaginal dilator, but I am quite certain that it is a vaginal speculum.  A speculum is used to inspect the vaginal walls and uterine cervix.  (That might be too much information my metal working/ engine making/ machinery minded readers.  If so, too bad.)

It is said to be made of bronze.  The Ancient Greeks were highly skilled at metal casting, as evidenced by the many complex and beautiful bronze statues and weapons and implements on display.

It interested me for several reasons.  Bear in mind that not many archeology museum visitors are gynaecologists who know about making threads in metal.

It looks quite functional, and if cleaned up, given a shiny surface and sterilized it could be used today.

The threaded section is very regular and smooth.  I would loved to have taken some measurements of the thread with a micrometer, but had to be content with a prolonged inspection through the glass case.  The thread appears to me to be so regular, that it could not have been hand filed.  It must have been machine made.  I have seen hand made threads on medieval machines, and they are crude compared with this one.

Either this is not an ancient Greek instrument but a more modern instrument accidentally included in the display (pretty unlikely, considering the professionalism of the people involved).  (ps.  If you Google Pompeii speculum, you will see that similar instruments have been unearthed at Pompeii…  buried since 79ce.)

Or…..  the ancient Greeks had screw cutting lathes.

Ridiculous you say?

Wait until my next post about the Antikythera machine.  If if you just cannot wait, look it up.   It is mind blowing.

 

 

Workshop Tidy

I sometimes feel a bit ashamed when I have visitors at my workshop.

The reason is that when I am in the middle of a project, I really concentrate my energy on the decisions, the machining, working out how to fix the mistakes…

…. and tidying up as I go, is near the end of the list of must do’s.

Consequently, tools tend to be put aside at the spot where I have been using them.  And off cuts of steel or brass or wood or whatever, lay where they fall.

And as mentioned in a previous post, I have a policy of leaving swarf on the floor, to discourage wildlife from slithering into my workspace.  (see the old post about the tiger snake between the lathe and the milling machine).   And if you are not Australian, look up tiger snakes.   They are just about the most dangerous reptile on the planet.

So my workshop is not the tidy, organised sort of workspace which you might expect from a retired gynaecological surgeon.

But occasionally, the mess becomes so extreme, that I cannot find tools, I trip over stuff on the floor, everything is really dirty, and it is dangerous and embarrassing when visitors call in.  And some of those visitors have workshops where you could eat off the floor.

So yesterday I spent a whole day tidying, sorting, putting away tools, throwing out rubbish, and sweeping the floors.

What about the tiger snakes I sense you asking.

Well, here in the antipodes, we are in the depths of winter, and it is bloody cold.  And all sensible cold blooded reptiles are asleep in their homes. So for a few months it should be safe to sweep up the swarf.   Here’s hoping anyway.

Ball Screws -2

This is a brief post to give a 10/10 rating to an Ebay seller with whom I have had dealings recently.

I have bought 2 ball screws and ball screw covers and ball screw bearings in 3 separate transactions from a supplier in South Korea.

Postage was included in the “buy it now” price.  In one case I offered a lower price, which was accepted within minutes.

After paying by Paypal, I received confirmation within an hour in each case, that the item had been shipped (actually air freight by Fed Ex).

In each case the items were delivered to my door in Australia within 3 days!  (it takes 5 days to get a parcel posted from Melbourne to Geelong, a distance of 65km).

And in each parcel there was a very nicely handwritten card thanking me for the purchase, and promising support if there were any issues with the items.

One ball screw was brand new, repackaged as advertised.  The other was used, salvaged from used machinery, but in “as new” condition.   Both were C5 grade, which is normally stratospherically expensive and has to be specially ordered.  They were priced only slightly higher than new rolled (lower grade) ball screws.

They were very carefully packaged in heavy duty cardboard rolls with metal ends, and multiple layers of heavy plastic and foam sheeting.

I made a later purchase which involved the seller removing a part from a machine.  He added it to a parcel which I had also ordered and wrote that I could pay later for the part if I was satisfied with it.  The price for the part (a THK bearing) was $UAUD32.  The same part new here would cost $AUD400.

In every case, communications have been  answered within a few hours, polite, personalised and in excellent English.

My only complaint, and it probably relates to the shipping arrangements, is that there appears to be a size restriction on shipping to Australia, of about 1200mm.  (p.s.  apparently the “do not ship to Australia” are old adverts, and there are no restrictions now.  A message to dy-global is all that is required to get any item shipped).

I hope to deal again with this company.  The name is dy-global.  To find them you need to search Ebay USA, or use the international settings on Ebay Australia.