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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.

Tag: John

CNC Lathe Conversion – 17

First Test Run

After some test runs without tool or material, I performed some measurements.

500mm movements along the Z axis were reproduced multiple times with a deviation of 0.00mm!  (the Z axis has a ground ball screw)

100mm movements along the X axis deviated 0.02mm.  (the X axis has a rolled ball screw).

I was delighted to note that the lathe is extremely quiet and smooth.  The only noise is some belt slap from the very old belts, and from the stepper motors.

The video below was taken from my iphone, while I was operating the lathe controls, so please excuse the erratic movements.

The steel is 27mm diameter.  750rpm, 50mm/min feeds.

And the guards will be made next step, without fail.

The G code was generated using Mach3 for these very simple shapes.  For more complex items I use Ezilathe.

 

The lathe is 600mm between centres.  38mm spindle bore.  Swing about 300mm.

NOT MUCH GOING ON TODAY

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This is my workbench after I had almost finished tidying it.  Really.  

 

Then I thought about machining the ends of the cross slide ball screw.

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So I mounted the collet chuck and checked the runout.   0 to o.01mm.  Then I did a test cut in the ball screw.   Hard hard hard.  But it did cut.  Then I chickened out and decided to finish it another day.

So, looking around the workshop for something else to do, I decided to pretty up the new CNC lathe apron.

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Before (milled surface).

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During

 

And I forgot to take a photo of the after, but it did look nice and smooth and shiny (look at the mirror finish behind the wheel).

Being retired is great!

JOINING DARK PLACES

Today I spent a couple of hours drawing CAD elevations of the high pressure cylinder steam passages, then generating some G codes for the CNC centre drilling, drilling, and tidying up of the steam passage connection to that cylinder.

Then I spent 30 minutes or so running the programmes.

All went well.  No drill bits broken in the depths.  No break throughs of dark passages into the cylinder bore, or into the bolt holes.  Whew.

The steam passages now open into the top and base of the high pressure cylinder. Intermediate and low pressure cylinders to be done ? tomorrow.

The steam passages now open into the top and base of the high pressure cylinder.
Intermediate and low pressure cylinders to be done ? tomorrow.

This is the drilling setup. I used a sine vice, sitting on gauge blocks, to produce an exactly 5 degree angle, to avoid the cylinder bore and the bolt holes.  The sine vice was held in the milling vice.

This is the drilling setup.
I used a sine vice, sitting on gauge blocks, to produce an exactly 5 degree angle, to avoid the cylinder bore and the bolt holes. The sine vice was held in the milling vice.

Other People’s Triples

Not sure about the position of the apostrophe.

But if, like me, you enjoy looking at engines, then stop thinking about the apostrophe and watch the videos.

John and John having fun again, on Puffing Billy

Puffing Billy, Belgrave, Victoria

Puffing Billy, Belgrave, Victoria, Australia

Big John and Little John, or Pop John and John John, on Puffing Billy.

Big John and Little John, or Pop John and John John, on Puffing Billy.

How a surgeon starts awkward, tiny nuts.

BA7 nuts are tiny. The thread is 2.38mm diameter. Admittedly, there are smaller nuts, but I have had so many problems with the BA7, that I do not want to even contemplate the even smaller ones.

If I drop a BA7 nut, I have about a 50% chance of seeing it on the floor. There must be a small fortune in BA7 nuts on the floor of my workshop, or wherever they bounce to.

The steam engine which I am currently building has several hundred of these tiny fasteners, and many of them are in inaccessible cavities, at least relatively inaccessible to my 65 year old fingers.

The more accessible BA7 bolts and studs can have nuts fitted with the assistance of a 4mm jeweller’s tube spanner. I added some usefulness to the tube spanner by turning its outside wall thinner, to decrease the space it occupies, but even so, there are many locations where no tube spanner, however modified, or open ender, or needle nosed pliers will reach, and fingers are required.

So, I had a brain wave yesterday, about a method of starting small nuts on relatively inaccessible studs and it works! This might not be an original idea, but it is to me.

It requires a sharp needle, on a handle, with an appropriate bend near the end of the needle. The sharp end of the needle is exposed. In my previous life I was a surgeon, so I have a supply of medical needles, and they are ideal.  A syringe makes a good handle.

The nut is placed on the needle, (carefully).

The needle point is placed in the centre of the end of the stud or bolt, carefully to avoid the nut slipping off prematurely, and the needle is angled so it is in line with the stud. The needle needs to be sharp, so it does not slip off the end of the stud.

The nut slips down onto the stud, and it can be spun with a finger tip until it attaches to the stud. The needle is then (carefully) placed away, and the nut is tightened down by whatever means are possible.

This method requires some dexterity, but it can change an impossible task into a merely difficult one.

Ps. If you use medical needles, make sure that they are new. Some diseases like hepatitis can be transmitted by needle stick injury.

The needle tip is pushed into the end of the stud/bolt.  The nut slips onto the end of the stud, and is then spun with a finger tip until it engages with the thread.

The needle tip is pushed into the end of the stud/bolt. The nut slips onto the end of the stud, and is then spun with a finger tip until it engages with the thread.

John and the jawbone of an elephant.

elephant jawbone.  Watch out for black mambas.

The guide told me to be careful, because snakes like to live in the bone cavities. We saw quite a few elephant skeletons, but no tusks! Because the government rangers collect the tusks, to prevent the poachers getting them. They reputedly have a huge warehouse full of tusks, waiting for the world embargo on ivory trading to finish. Botswana has a total ban on hunting, and consequently has a problem with elephant overpopulation.

WHERE’S WALLY

Africa 186

Buying Tools and other stuff at a swap meet.

Today I drove with a friend to Ballarat, Victoria, Australia to the biggest swap meet in the Southern hemisphere, maybe the biggest in the known universe.

It is located on an aerodrome in country Victoria.  Approx 2500 stall holders selling stuff from shed cleanouts, factory close downs, farm sales, and some commercial sellers.

A lot of the stuff on sale seems to be total junk, with the vendors sitting around enjoying the sunshine, the conversations, the beer and barbeques.  A lot of them stay in tents and caravans on site.  But there are many gems and bargains, and that is the reason I find myself drawn back to the event, annually for the past 4 years.

The atmosphere and mood is relaxed and pleasant.  A fair bit of good natured haggling and bargaining goes on.

You do have to keep an eye out for kids on bikes whizzing about.  It is supposed to be a car free zone, but I noted far too many vehicles driving about raising dust.  The organisers need to get on top of that issue.

I was also a bit peeved to have to pay $3:50 each for a small plastic bottle of water.  It was a hot day, and several of these were required.  The price was feasible because there were no other visible sources of drinking water.

But I was very happy with my purchases.  Photos following.

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Hats, sunscreen, and fluids essential. 34 degrees C.

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Amazing eclectic variety of stuff on sale.

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I estimate that I walked 10km checking out about 50% of the sites. Too many to see in one day.

SOME OF THE STUFF WHICH I BOUGHT.  IT REFLECTS MY OWN INTERESTS RATHER THAN THE VARIETY OF ITEMS ON SALE.  MY FRIEND BOUGHT A HEAP OF PARTS FOR HIS MINI MOKE.  THAT IS HIS PARTICULAR INTEREST.

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A heavy duty, well constructed welding earth clamp for $10.

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Some bronze manganese welding rods for $15. I will check their machineability.

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A miniature internal threading tool with inserts. Expensive at $130, but good value.

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A 1″ m3 step drill (new), and a used but good condition 1.5″ M4 drill bit. $30 total. Great value.

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2 cobalt 9/16″ drill bits for $6. Only one size available. Amazing low price.

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A pair of razor sharp Japanese wood chisels. Pricey at $70, but the conversation I had with the Japanese cabinet maker who was selling them, was priceless. The handles are rosewood and oak. The steel is laminated, similar to samurai swords. I look forward to trying these.

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A Mamod steam tractor. It seems to be in reasonable condition, and complete. I told SWMBO that it is a present for a grandson when he is a bit older (2 years old now), but we will see. I really like it myself. Is 64 too old to be playing with toys? Was said to be in working condition, but I expect that some renovation will required.  Price not for disclosure to SWMBO.

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This was the most interesting purchase. 3 “Model Engineer and Amateur Electrician” magazines from Sep to Dec 1900. $5 each. The articles about “using electricity in the workshop” were sobering. It was nice to see articles about lathes apart from Myford discussed. (Drummond most common). Not sure where these magazines will end up. They should be on display, or in a museum.


More Inca stonework. Awesome.

Our guide at the MachuPicchu quarry explains how the Inca stonemasons chipped rectangular slots then hammered in wedges, or allowed water to freeze and expand, to split the stone.

Our guide at the MachuPicchu quarry explains how the Inca stonemasons chipped rectangular slots then hammered in wedges, or allowed water to freeze and expand, to split the stone.

MachuPicchu quarry

MachuPicchu quarry.  The piece on the ground has been split off, about 500 years ago, ready to be painstakingly shaped and fitted into a wall.  

A displaced, shaped block at Cuzco.  Shows how the block is shaped on all faces.

A displaced, shaped block at Cuzco. Shows how the block is shaped on all faces.

The blocks were fitted together, and then often joined with lead or silver, which was poured in a molten state into the grooves. Recovering the silver was possibly one of the reasons why the Spaniards demolished many Inca buildings.

The blocks were fitted together, and then often joined with lead or silver, which was poured in a molten state into the grooves.
Recovering the silver was possibly one of the reasons why the Spaniards demolished many Inca buildings.

Try fitting a razor blade or even a hair into that join.

Try fitting a razor blade or even a hair into that join.

The attention to detail was at an incredibly high level in the royal buildings.

The attention to detail was at an incredibly high level in the royal buildings.

Apart from the accuracy of the stonework, the architecture shows amazing accuracy.

Apart from the accuracy of the stonework, the architecture shows amazing accuracy.

another groove for molten silver or lead

another groove for molten silver or lead

Note how the block curves around an inside corner

Note how the block curves around an inside corner

And outside corners.  Quite beautiful.

And outside corners. Quite beautiful.

Some blocks weigh several tons

Some blocks weigh several tons

This is apparently a phallic reference in stone.

This is apparently a phallic reference in stone. Count the number of faces on the central stone.  It is quite famous.

Peru

Ok.  This is under the “Other Stuff” heading.

I have not done much in the workshop lately, so, I dug out some photos of a trip I made in 2008 to Peru, with my daughter Elisabeth.  I took heaps of photos, but these are some of my favourites.

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Some of the awesome stonework in Cuzco. Built by the Incas 500-600 years ago. The Spanish invaders demolished the “pagan” buildings above and built their own buildings on the Inca foundations. The locals laughed when earthquakes repeatedly demolished the European parts of the buildings and left the Inca bits undisturbed.   Note the continuity of the horizontal lines.  How much effort would  have been required for the architect-stonemasons to ensure that continuity.  And apart from the beautiful aesthetic it produces, I wonder if that continuity has any other significance?  

 

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About half of Peru is Amazon rain forest. My daughter Elisabeth worked in an animal refuge near Iquitos, in this region. Looking after panthers, anacondas, monkeys and others, which had been brought to the refuge after being injured. Yes, my daughter is an amazing person, and I am immensely proud of her.

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Elisabeth with some of the locals in their traditional dress. They are happy to pose for photos for a very small fee.

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Huge stones fitted together so tightly that a razor blade cannot be passed into the gaps. Ancient aliens must have done this! Or very clever and determined Incas.

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Yes, I became addicted to looking at the stone work. It was amazing, awesome, unbelievable and beautiful.

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Hand woven rugs for sale to the tourists. Cheap.

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Our first day of a 5 day hike to MachuPicchu. Not the regular tourist route. In the background is Mt Sankaltay. I could understand why they thought it sacred. We camped near its base, next to a glacier.

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The first night our tents and the ground were covered with about 100mm of snow. Quite an experience for someone from Australia. The next morning we climbed to 15,000 feet, slowly. The glacier is in the background. We are close to the top of the pass in this photo.  That is me in the foreground.  When the guide found out my age (60)  he wanted to put me on a horse!  No way!  Horses hate me.

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The locals have striking attractive faces.

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There were 2 horse handlers. The horses carried our tents, food and supplies. We carried day packs only. 2 Canadians, Elisabeth and me. I was the oldest and the least fit, and the slowest, but I made it. I imagined that if I had a health problem, I could be helicoptered out, only to learn that helicopters cannot reach these heights. The trails were sometimes very narrow and quite dangerous, cut out of cliff sides, and sometimes rough creek beds.

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MachuPicchu. Breath taking.

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MachuPicchu

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The agricultural terraces at MachuPicchu, and some restored buildings. Only a few of the buildings have been restored, to show what they would have looked like in their heyday.

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Me, on a floating island on Lake Titicaca. The locals are very tiny, They lived on the lake to escape the Incas, who were expansive aggressive and violent. The islands are made of reeds which are bundled together, and replenished every year. It was cold. Extraordinary.

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The characteristic doorway shape of the Incas.  Note the incredibly tight joints, made by non metal hand tools, which have withstood earthquakes, conquistadores, and 5 centuries of weathering.

The characteristic doorway shape of the Incas. Note the incredibly tight joints, made by non metal hand tools, which have withstood earthquakes, conquistadores, and 5 centuries of weathering.

GSMEE EXHIBITION 2

Wimshurst Electrostatic Generator, made by Peter Bodman.  Creates sparks up to 100mm long, which drill minute holes in interposed paper sheets.  No-one volunteered to ry it with a hand.

Wimshurst Electrostatic Generator, made by Peter Bodman. Creates sparks up to 100mm long, which drill minute holes in interposed paper sheets. No-one volunteered to try it with their own hand.

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Vacuum engine made by Peter Bodman.

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Awesome model of pre-dreadnaught ship circa 1902 “Preussen” made by Walter. It is approx 1 meter long, weighs 16kg, and is radio controlled. The 28cm gun turrets are also radio controlled, but do not (as far as I know) actually fire.  To the right is a model of Columbus’s “Santa Maria”.

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The detail in the model has to be seen to be believed.  Every plank of the decking is individually made and fitted.

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Walter showed us the inside construction, engines, and electronics. The model was made from a few old photographs, and simple side and top elevations.

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Hull with the superstructure removed

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A very old pressure gauge, restored so that the workings are displayed, to reveal how it works. By Stuart.

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This model boat was made by 8 year old Niall, with some supervision from his Dad, William. The gun is actually a radio controlled water cannon which fires up to 3 meters, to the wet surprise of some spectators. Niall and William both had a fantastic experience with this project.

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William with some of the wonderful boat and ship models which he (and Niall) have made in recent years.

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A model working ship steam engine and boiler, by Walter. Twin cylinder, double acting cylinders. This should be jewellery, worn around the neck of a beautiful woman.  OK, that is a little over the top, but you get the idea

 

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Close up of the marine engine by Walter

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Les Madden with his partly completed Atkinson Differential Engine Model, originally patented in 1887. The wooden model on the left was built by Les in attempt to figure out how it worked! He made the wooden parts to have aluminium castings made.

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Les Madden’s Differential engine.

18 radial cylinder aero engine, by John Ramm.  The hand carved propeller is approx 600mm long.

18 radial cylinder aero engine, by John Ramm. The hand carved propeller is approx 600mm long.

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Detail of the aero engine. John showed 3 aero engines. He is currently making a 12 cylinder Spitfire Merlin engine which he will have finished by the time of the 2015 exhibition.

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Stuart Tankard’s prize winning hit and miss engine, was running throughout the exhibition. 17.7cc, 4 stroke, 4:1 compression, running on gas.

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Close up detail of the hit and miss engine. A standard the rest of us can aim for.

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A vertical boiler made by Stuart Tankard

Thomas Lord in the cabin of his steam truck, giving some driving tips to Niall

Thomas Lord in the cabin of his steam truck, giving some driving tips to Niall

These photos are just a small fraction of the many model engines, ships, trains, tools and other projects created and displayed by members and friends of GSMEE.

GEELONG SOCIETY OF MODEL AND EXPERIMENTAL ENGINEERS ANNUAL EXHIBITION 1

Steam truck, built by Thomas Lord.  See following videos

Steam truck, built by Thomas Lord. See following videos

The GSMEE held its annual exhibition of projects by members and friends, on the weekend of 15-16 November 2014, at Osborne House, Swinburne Ave, Geelong North.
I will post some pictures and videos of some of the superb model engines, boats, ships, tools, aero engines, and even a full size road legal registered steam truck, pictured above. Due to the size of the files and the crap Internet connection available here, I will spread the post over several days.

To continue with the incredible steam truck, made over the past decade by Tom Lord, see the following videos.  (sorry, no luck with the upload. I will try again tomorrow)

 

Beam Engine Driving Wheel 2

The aluminium disk was drilled then reamed to 19.05mm (3/4")

The aluminium disk was drilled then reamed to 19.05mm (3/4″)

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Then a shaft was pressed into the disk. The shaft is the same as the shaft on the beam engine, in fact it is from the same stock. It was centre drilled at the ends in preparation for turning between centres, and shaping the driving wheel.   This should result in a wheel which runs true and does not wobble when installed onto the beam engine. 

Beam Engine Driving Wheel from a Big Lump of Aluminium

16kg aluminium rod.  Cutting off using a band saw.

16kg aluminium rod. Cutting off using a band saw.

I bought a 130mm diameter lump of aluminium rod, 460mm long, weighing 16kg, off ebay. It was described as excellent machining material, so I put it to the test. I need a driving wheel for the beam engine.

The driving wheel fits between the flywheel and the governor column.

The driving wheel fits between the flywheel and the governor column.

The aluminium disk straight off the band saw.  A perfect cut from a well adjusted saw.   Took about 5 minutes to make the cut, using plenty of cutting fluid and slow descent of the blade in order to avoid jamming.

The aluminium disk straight off the band saw. A perfect cut from a well adjusted saw. Took about 5 minutes to make the cut, using plenty of cutting fluid and slow descent of the blade in order to avoid jamming.

It turned beautifully.  Using a HSS tangential  tool.  You can see a mirror reflection even as the turning as happening.

It turned beautifully. Using a HSS tangential tool. You can see a mirror reflection even as the turning as happening.

TAPPING HOLES. BOLTON 9. (Triple Expansion Marine Steam Engine)

Today I drilled and tapped the holes for the bolts which secure the crankshaft main bearings.  I had accurately marked the bearing mounts  in the previous session (see previous photos), and calculated and recorded the DRO (digital read out) position for each hole.  So going back to that position for each step in the process was easy and quick.  The steps today were centre drilling, drilling the 3.3mm holes, and tapping the 4mm threads to a depth of 20mm.

Centre drilling is done with a centre drill bit in an accurate chuck in the milling machine.  Centre drill bits are inflexible and will not wander over the work like an ordinary twist drill bit,  The centre drilled hole is deep enough to create a chamfered edge to the hole.  All 12 holes are drilled with the centre bit, then all 12 drilled with the 3.3 mm bit, then all 12 are threaded.  The DRO positions the work within 0.005mm each time, and the repositioning is very fast, much faster than going to a position doing all 3 processes, changing the bit for each one, then moving to the next position.

The threading was done with a Tapmatic 30 tapping head in my milling machine.  See photo.  This takes about 10 minutes to set up, but the tapping process for the 12 holes then took about 5 minutes.  I use Rapid Tap lubricant for tapping, even in brass.  I guess that manually tapping the holes would have taken about the same time, but it was so satisfying to see the Tapmatic do its stuff.  I use the Tapmatic for any tapping job involving more than about 8-10 holes.  Fewer than that it is quicker to do them manually.  The Tapmatic has a adjustable clutch.  I have never broken a tap in the job using this machine.

Incidentally, I have decided to use nuts and bolts and screws and studs in preference to metric cap screws for this model.  The appearance wins out over practical expediency.  So why the metric threads for this job today?  The specified thread was 5/32″ which is 3.96mm, so I decided to go with the 4mm metric, for which I have the tools already.

 

Tapping the main bearing blocks using the Tapmatic and Tap Magic.

Tapping the main bearing blocks using the Tapmatic and Rapid Tap.

TRIPLE EXPANSION MARINE STEAM ENGINE 3

I had almost 8 hours in the workshop today.  The base plate is progressing.

 

Sheet 1 of 3

Sheet 1 of 3

Milling the main bearing housing slots

Milling the main bearing housing slots.  Using a 14mm HSS end cutter.  Ended up blunt.  There must be some embedded casting sand still

Then I spent an hour or so painting the machined surfaces with marking blue, and marking reference points and edges.

Using a Knu vice to cramp the base plate to and angle plate, and a height gauge to mark the reference lines

Using a Knu vice to cramp the base plate to and angle plate, and a height gauge to mark the reference lines

Top view of the marking out lines

Top view of the marking out lines

After machining the main bearing housings, the big end slots and the eccentric slots.

After machining the main bearing housings, the big end slots and the eccentric slots.

TRIPLE EXPANSION MARINE ENGINE 2

Reducing the width of the aluminium plate to 140mm, so it will fit into my milling vice

Reducing the width of the aluminium plate to 140mm, so it will fit into my milling vice.  The plate is clamped to an angle plate.

Squaring the ends.

Squaring the ends.

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The base plate bolted to the aluminium plate. Care was taken to fix the brass base centrally and parallel to the aluminium. The fixing bolts are 3mm cap screws, and the holes through the brass plate are 3mm, so even if the brass base is removed, it will go back on in exactly the same position.

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I finished the day by making a spur gear for my brother’s lathe.

 

The gear attached to the shaft using Loctite.  If the Loctite is inadequate, the gear can be pinned to the shaft.   In the post tomorrow, to Townsville QLD.

The gear attached to the shaft using Loctite. If the Loctite is inadequate, the gear can be pinned to the shaft. In the post tomorrow, to Townsville QLD.  The photo shows why metalworking is an unsuitable hobby for a gynaecologist.

TRIPLE EXPANSION STEAM ENGINE 1

The base casting.

The base casting.

The base of the base, machined flat

The base of the base, machined flat

The base, with 6 pillar mounting areas machined parallel & coplanar, and the crankshaft mounting blocks after an initial skimming.

The base, with 6 pillar mounting areas machined parallel & coplanar, and the crankshaft mounting blocks after an initial skimming.  Slots for big ends roughed out.  2 hour first machining session.  2998 hours to go?

After carefully examining the base casting, and scrutinising the plans to discover all of the dimensions of the base, I commenced machining on my King Rich mill (Bridgeport clone, NT40 with DRO, an excellent machine). Since the base dimensions are scattered over 3 pages of very complex plans, and I am still relatively unfamiliar with them, I am approaching the machining with great caution. At this stage I am aiming to create some flat and coplanar surfaces, with a margin of material remaining, so I can hold the base flat, without rocking, roughing out the shape, and leaving finishing to dimensions at a later date. I intend to attach the base to a rectangular piece of aluminium, so the aluminium can be clamped or held in a vice, rather than risking damaging the brass casting.

CASTINGS ARRIVE AT LAST!!

Today I received a 16.6kg package by courier. It was too heavy for the regular post.  It contained the castings for the model triple expansion steam engine, which I am hoping to build in the next year or so.  I am told that on average this model takes 3000 hours to complete.  That is a scary thought.  Almost unbelievable.  But when I calculate how many hours went into the much simpler single cylinder beam engine (maybe 600-800), I guess that it is not an unrealistic estimate.  Just as well that I am close to retirement age.

The castings were made in NSW Australia, and supplied by Kelly Mayberry at EJ Winter.

All carefully wrapped

All carefully wrapped

The castings are all brass, gunmetal, or bronze

The castings are all brass or gunmetal.  There must be at least 100 of them.

Looks like the condensor chamber, as part of the engine frame.

Looks like the condensor chamber, as part of the engine frame.

The base.

The base.

A large chunk of brass

A large chunk of brass, the intermediate and low pressure cylinders.

The castings appear to be free of holes or defects

The castings appear to be free of holes or defects

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