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.

Bad Paint Job

As I reported on Sep 3, I was recovering from a decent dose of influenza, and feeling a need to do something after almost 2 weeks of inactivity, and I decided to put some more paint on the Trevithick dredger engine.  After all, what could go wrong?   Just a bit of gentle painting.

I was quite proud of the job.  No paint spills.  No brush marks on neighbouring items.  No brush hairs in the work, and minimal brush marks.

I wondered how long I would need to wait between coats, so I checked the paint tin.

O shit!   I had used the wrong paint….

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I had used the epoxy enamel instead of the high temperature resistant Pot Belly Black!  The brain had apparently not recovered fully from the ‘flu.

I decided to sleep on the problem.  Checked with my resident paint expert (SWMBO), and on her suggestion, next day applied some mineral turpentine.  The paint was dry, but the turps did seem to soften it.  So I applied some more turps, then attacked the epoxy paint with a rag.

To my delight, it mostly came off.  I was not too bothered by the paint in the deep cracks…. that could be a filler.

Then I carefully dried everything, another rub with clean rags, and applied another coat.  This time using the correct paint.  2 coats.

Reader Huib asked how it had all eventuated, so today I took some pics of the engine in its current home…  our kitchen.  The budgerigars are SWMBO’s decorative touch.

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The kitchen is due for a renovation.  I made those cupboards and benches 30 years ago.

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But the paint job looks ok hey?

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Another view.  In the background is a painting of a dog training group in the grounds of the MCG, by Samantha Lord.

Hey readers (male and female), waiting for more workshop photos to post.  It doesn’t have to be the whole workshop…. just a photo of your favourite machine would be great!

The Boer War. A Book Review. Excellent!

THE ANGLO-BOER WAR IN 100 OBJECTS

 

After reading this book, cover to cover, in 2 days, I felt that I had a real grasp of the reality of the 1899-1902 war which so shaped South Africa’s history. I now realise that my previous knowledge of the war was very sketchy.

 

The 100 iconic objects which are held in the War Museum of the Boer Republics, and 200 other objects, maps, and many photographs, are beautifully presented in this high quality book of 260 pages.  The story of each object is told in short essay style by gifted, expert writers.

 

The many subjects include battles, weapons, military personalities, politicians, places, civilians, equipment, prisoners of war, concentration camps, costs of the war, and longer term outcomes.

 

The book does not glorify the Anglo-Boer War.  If anything, it is an anti-war treatise.  It certainly has had a major impact on this reviewer.

 

Thoroughly recommended.

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Southworth Steam/Water Pump

I am progressing my Southworth pump.   Today, Stuart brought his completed version, so I photographed the incomplete and complete versions together.   Actually, it was very useful to see Stuart’s pump again.  An obvious difference in one of the components made me realise that I had made a mistake.   Now rectified.

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My incomplete version and the working version.

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Stuart’s working version.

Three more workshops. Why are they all so neat? Or am I just very messy?

Reader Tim from NSW, Oz, sent these pics

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Optimum mill, Chicago compressor “very quiet”,  Myford Super 7 lathe, drill press.

 

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Optimum 6″lathe, drop band saw, linisher.   Plenty of light.  No swarf on the floor (no snakes apparently).

And from Victoria Oz,  Neil sent these shots of his workshop, with some work in progress visible…

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Reading Neil’s signs reminds me of a sign which I saw on someone else’s mill or lathe… “Not to be operated by fuckwits”.   Maybe I should put up such a sign on in my workshop, but then, it might invite comments about the current occupant.

And finally, my friend and mentor Stuart’s workshop…

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This is Stuart’s kitchen, which he is putting to the best use!   Note the laser cutter, which will cut metal up to 1mm thick, and the optical comparator.   But does the laser slice the toast, Stuart?

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Stuart’s actual workshop is the garage.  The car, very sensibly has been expelled to the outside.  Note the Boxford CNC lathe (the same as my Boxford CNC lathe), and the old green manual lathe on the back wall, still gets a lot of use.  Disgustingly neat and clean.   Starting to get a complex about this.

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And in the other direction is Stuart’s CNC mill (blue base), CNC router on the bench.

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And finally, I decided to add a shot of the spare bedroom in my home.  Note the Boxford CNC lathe,

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This is the spare bedroom in my house.  You are welcome to stay, after moving some stuff.

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My Boxford CNC lathe in the spare bedroom.  Well, no-one comes to stay very often!

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Another view of the spare bedroom.  2 Boley jeweller’s lathes.  They do occasionally get used.

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And another view of the spare bedroom.  Plenty of bedtime reading.  And another jeweller’s lathe in case you get the urge in the middle of the night.

So there you are.   Please send your photos of your heaven on Earth.

 

 

TWO WORKSHOPS

This post was inspired by one of my readers sending me some photos of her workshop.  The photos grabbed my attention for several reasons.

Firstly, the metal working machines share the space with tomatoes!  Unusual, eclectic use of the space.  Secondly, the roof and walls are made of glass!   Great for natural lighting, and nice views for the machinist, and possibly the neighbours.  Thirdly, it is such a small space, requiring planning to accomodate quite a few machines and work space.   And fourthly, it is so neat and clean.  I do see an occasional bit of swarf, but it is so unlike the mess that I work in, that it is quite striking to see such a clean workshop.

Thanks to reader Jennifer for sending these photos.  For obvious reasons I will not publish further location details except to reveal that the location is in the UK.

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Jennifer tells me that it is all double glazed, and is open to the living area of the house, so it is heated.  Apparently it never becomes too hot in summer.

And as a complete antithesis, this is my main workshop in Oz.  Bigger, messier, dirtier, darker.    Actually, when I looked over my photos I could not find one decent view of my workshop, so I took some new pics.  Needless to say, there was no special tidying for the photo.

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It is a tin shed, unlined, but does have a wood heater.  This view takes in about 2/3 of the area.  There are 3 lathes in this shot.  Can you see them?  CNC lathe in foreground.  Also my CNC mill on the right.  There is also a tool and cutter grinder, vertical bandsaw, drop bandsaw.  And lots of ancillary tooling.

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And a pedestal drill, 2 linishers, grinder, and part view of the drop band saw.  The anvil gets quite a lot of use.  It is mounted on heavy duty wheels so I can take it to the job.

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My workbench in the foreground, A very heavy cast iron setup table (blue) with granite surface plate.  Shop made ring roller centre.

So, that is where I spend most of my waking hours.  The shed started life as a farm workshop, where a lot of welding, and repair and maintenance of farm machinery was done.   These days it is mainly used for model engineering.  In my working life I was an obsessively neat, organised and particular surgeon.  Not quite sure how my activities ended in this mess.  But you know what?… I feel totally comfortable here.

 

 

If you have some photos of your own workshop area, please send them in and I will publish them for the interest of other readers.  Big areas, small areas, old machines or new.  Show us where you spend your most enjoyable hours.   Send them to me at jviggers@iinet.net.au

 

 

 

 

Fit after 9 day influenza?

Today is the first day since I became sick that I have felt able to drive.  Until today I have been experiencing coughing paroxysms, severe headaches, dizzy episodes, even 2 episodes of hallucinations which were really weird.  Also requiring pain killers regularly.

My GP thinks that I have had influenza A, despite vaccination earlier in the year.  Certainly the nastiest bug which I have encountered in many years.

But as today warmed up, and I had not required any analgesics, and the coughing was settling, I decided to visit my workshop.   “Visit”, rather than operate machines.  I suspected that my mental faculties were not yet 100%.   It is a 20-25″ drive to my workshop, so off I went.

I was pleased to note that my neighbour had mowed the grass around my sheds.  It had become quite thick and high, and with the warmer spring weather today, I was not looking forward to walking through the thigh high vegetation which could conceal nasty poisonous fauna.  The neighbour has long term loan of my tractor and slasher, and the quid pro quo is that I get my grass mowed whenever required.

So what to do, not requiring turning on potentially dangerous machines?  I decided to look at the Trevithick dredger engine.  It has been waiting for some painting.  That would not be too arduous or too dangerous!

The engine end of the boiler was waiting for some flat black paint.  So I removed some appendages, filed and wire brushed the surfaces, and washed them down with mineral turps.  Found the paint, stirred it thoroughly, and carefully applied it with some small, new brushes.

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The engine end of the machine, with one coat of the flat black applied.  Hmm…. I don’t remember it going streaky like that before…..   Maybe the second coat will look better.

I used the paint to touch up some other areas also.

Then as I was cleaning up, before going home I took another look at the paint can.

O shit!  I had used the wrong paint can!

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I should have used the “Pot Belly Black”.  Somehow, I picked up the other one.  The “Rust Guard Epoxy Enamel” is good paint, but it might not tolerate the surface temperatures of the boiler.   And an etch primer is recommended for it, which would explain my application problem.

So what to do?   I know that most of you will be screaming at the screen, to strip off the epoxy paint and start again.  But, for better or for worse I have decided to apply another coat of epoxy tomorrow and see if the appearance improves.  I expect that it will.  Then a trial firing in a few days will demonstrate whether the epoxy will cope with the temperatures.  If it copes…. fine.  It is well away from the furnace.   If not, then a very time consuming strip job and repainting will be in order.

It seems that my mentation has not fully recovered.

Houseguests

Just to explain the long interval between posts.

About a week ago I felt a bit off, headachey, but I had just driven through Melbourne peak hour traffic, so was not too concerned.

But the next day my head was going to explode, my chest ached, my skin was painful, and I was experiencing chills and sweats.   That has all continued.  I assume it is a viral infection, but it is taking longer than usual to start resolving.   And now I have started persistent coughing.  Might have to see the quack.

So I have not been in the workshop for a week.  And I am getting a bit bored.

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They are eating a banana handed to them by my wife.  The baby came out of its mothers pouch about 2 months ago.   If the baby is a female, she will become part of the house fauna.  If male, he will be booted out at when about 12 months age.

No, they do not have names.  But they do come down when my wife calls “possum, possum”.

We have encouraged this family for many of their generations by not frightening them, and feeding them.    Possums live in many Australian roof spaces.  They are difficult to keep out, and it is illegal to remove them further than the confines of the property.   So trapping and removal is usually temporary.

They entertain us, and visitors.   Never cause bother.  Well, almost never…   they found a way into our pantry once, and raided every open packet of cereal, raisins, etc., throwing the unwanted packages onto the floor.   We just looked at the mess and laughed.

 

 

Southworth Steam Pump- first parts

A couple of days in the workshop, and the large castings are almost fully machined.  Straightforward machining.   Made a couple of mistakes, but none fatal.  Changing BA fasteners to metric.

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The steam cylinders block in the mill vise.   Almost complete water cylinders block sitting behind for the photo.

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Steam cylinders on right, water cylinders on left.  The temporary steel pins are to ensure accurate alignment of the 2 blocks.   Water and steam passages come later. 

This is the first model machining which I have done since April.  It should be second nature, but I admit to a bit of hesitation, nervousness, initially.  Especially starting on an irregular, slightly complicated shape like these.   But it is all coming back now.  And I am really enjoying it.

Steam Powered Water Feed Pump

My CNC mill is now mostly functioning, although several functions are yet to be connected.  The main spindle and XY&Z axes are working, and responding appropriately to Mach3 commands from the laptop computer.  It has taken longer than anticipated so far, mainly due to difficulty in understanding manuals supplied from Asia.   Axis limit and homing switches, oil pump, coolant pump, work light, and cooling fans still to be connected.

So there has been little of general interest coming out of my workshop.  Hence no posts on this site.  Not that I have been idle.

I disassembled the top slide on the Colchester lathe to discover the cause for excessive back-lash.  It was a worn acme thread bronze nut.   No luck yet in finding a new nut for this 45 year old lathe.   I will have to make one.  Meanwhile, I used a quick and dirty trick to reduce the back-lash which I will detail soon.

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The top-slide acme screw and bronze nut which needs replacing.

I also cleaned and freed up a 3 jaw 10″ chuck which I bought on Ebay.  It was frozen solid, so I soaked it in kerosene bath for a few months.  Actually, I forgot all about it while it was in the kerosene, and accidentally rediscovered it.   This time, after using an impact screwdriver, I was able to open it up and expose the gears and get them moving.  Might be worth a photo also.

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The 240mm diameter chuck.  I was tempted to buy by the removable, reversible  jaws.  Thinking that I could make some soft jaws.   Trouble is that it is an industrial production line chuck with very little movement.   But it is nice and tight.  Still deciding.  At least I can wind the jaws in and out a bit now.

And I finally got around to installing piston rings in the triple expansion steam engine.  Used Viton O-rings.  Not a difficult task, and it should not be difficult to replace them from time to time in future.   Will be interesting to see if the engine performance improves.

Now to get onto my next project.  I have plans and bronze castings for a Southworth design water pump, for replenishing the vertical boiler water while it is in use.  It was a surprise to me, just how much water is consumed by a boiler which is powering a model steam engine.  To date I have used a hand pump, but having seen a steam powered pump in action, I have decided to make one.

The steam is supplied from the boiler which is being replenished.  The pump has to use steam at boiler steam pressure, to force water into the boiler.  So the pump has to raise the pressure of the feed water above the pressure of the steam which is powering the pump.   The clever pump design uses large steam driven pistons to drive smaller water pump pistons.

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Larger steam pistons top right 5/8″ dia,  water pistons bottom left 3/8″ dia.

Here is a video of a Southworth pump in action.  It was made by Stuart Tankard.  Here it is running on compressed air, but I have seen it working similarly on steam.  I will be making one of the same design, hopefully approaching this level of finish.

 

 

A build of larger version of the pump was described by J. Bertinat in  a series of articles “Model Engineer” in 1993 (first article 18 June 1993).

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The unmachined castings.  Lumps of rough bronze.   And the plans.

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One of the castings after preliminary machining to establish some faces.  The “water cylinders” block.   Part no. 6

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Good quality castings.

 

 

CNC Mill Upgrade -8

Fitted the new VSD Friday.  Ordered Tues pm.  Arrived Thurs am.  Impressive.

$AUD315, inc shipping.   Job cost is mounting.  Still within reasonable limits.

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The old VSD, top right.  The axis controllers (top left) had not been wired when this photo was taken.

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The new VSD (variable speed drive) 4kw.  Fitted neatly with some new mounting holes, without any drama.  The rats nest looks less daunting every day.

Now, except for the main spindle motor, there are no more original major electrical components.  All have been updated and replaced, along with the cables.

Yet to be wired are the VSD, coolant pump, oil feed pump, limit switches, homing switches, and the Gecko driver and 48v power supply for the rotary table.   But the mill is useable now.   Video coming up soon.

 

CNC Mill Upgrade – 7.

2 steps forward, 1 step back.   That’s what this project is experiencing.

The axis servo motors, their controllers and connections to power, breakout boards, and computer connections are complete, and all working.

An old laptop has found a use.  Installed Mach3, Vectric V-Carve Pro.   And the connections to the Smooth Stepper board.  Windows 10.   Deleted all non CNC related programs to gain space on the hard drive.

A problem with the main spindle.  It is essentially unchanged from the original.  Same motor (4kw/5hp 3 phase), same VSD, and same 3 phase power which is supplied through a phase changer, because the property has only 2 phases supplied.  When powered up, it worked, but the RPM’s could not be altered from a very slow rate.  The controlling voltage from the breakout board was not changing despite changing the inputs.  ? due to a problem with the settings, or a faulty BOB.  Didn’t seem serious.

So I was a bit surprised when later I switched on the mill, intending to change some settings, to hear 2 significant pops, and to smell that disgusting burnt electrical component smell, with smoke coming from the electrical enclosure.

Quickly shut everything down, and waited for the cavalry to arrive.

Stuart found that a 24v power supply had failed.  No big deal.  Not an expensive component.  Maybe got a short circuit from a bit of swarf?   But further inspection revealed that the VSD had also failed.  A capacitor and diode burnt out.  ? caused by a surge from the failing power supply? Repairable, but I decided to buy a new VSD.  The failed VSD is probably as old as the mill (24 years), so it had a pretty good run.  If the old VSD is repairable, it will serve as a spare.

Meanwhile, as a consequence, the main spindle is not working.  I have a list of jobs that I want to get into, particularly the steam pump for the vertical boiler.   So I will reattach the high speed spindle and use that.  It is 2.2kw, but uses high revs to develop power, so I will be limited to small end mills and drills, until the new components (VSD and power supply) arrive.  The high speed spindle is single phase, and the speed control is manually selected.   Not quite as convenient but useable for the time being.

While Stuart has his head buried in the electrical enclosure, I have been his gopher and TA.  But also fitting in a couple of other jobs which have been on the “to do” list for ages.  Like clearing out rubbish from the workshop, tidying up etc.

One task which has been vexing me, was to remove a sheet of flooring board which was under the Colchester lathe.  The sheet was originally placed under the lathe to protect the vinyl floor covering, but it was not a good decision.  As the flooring board became wet with cutting oil and coolant, it would swell and shrink, and I was aware that the lathe levels and settings were changing.  So I decided to remove the sheet of flooring, and let the lathe feet sit directly on steel pads on the vinyl/concrete floor.

But how to remove the sheet of flooring from underneath the almost 1 ton lathe?  The lathe was originally placed into its rather tight position with a forklift, which is no longer available.  The wooden sheet was the same size as the base of the lathe.

So I made these…

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The bolt adjusts the height of the jack.

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From a piece of scrap I-beam.

I used a crow bar to raise the corners of the lathe enough to place the jacks into position.  A bit of trial and error to get the heights correct.    When the lathe was about 25mm clear of the flooring, I pulled the sheet out.  Then used the crowbar to remove the jacks, and lower the lathe onto its base plates.

I will reset the lathe’s screw feet in the next day or 2, using a precision level and test cuts.  There was an excellent YouTube video by “This Old Tony” on the subject recently.

 

CNC Mill Upgrade – 6. Where to put the computer?

Not much more to report today, but I have decided how to position the computer.

Not easy, because the computer needs to be protected from flying swarf and coolant spray from the CNC mill and the manual mill which is immediately adjacent.    And I want the computer to be close to the machine.  The CNC mill is NOT in an enclosure.

So this is what I have decided….

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The laptop is just low enough to reach while standing.   The E stop and other buttons are underneath.

And if the swarf is really flying, I can turn the PC away…

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Might need some adjustments.  The laptop is an old Dell ATG.   Said to be resistant to fluids and relatively resistant to shock/vibration etc.   Military specs.   I might add some side protection and perhaps a roof.

 

 

CNC Mill Upgrade -5

I have been putting quite a few hours into the upgrade, but not much to show photographically.

Finally got the new servo motors installed.  Replaced the X axis belt.  The most difficult servo to access was the Y axis, and of course that was the only one where the alignment of the timing belt was out.   Finally sorted by using a fibre optic camera to see why the belt was climbing onto the flange of the pulley.  The pulley was 1.2mm too far onto its shaft.  I know that, because I solved the problem by inserting washers under the motor mounts.  1mm washers did not work, nor did 1.5mm washers.  But 1.2mm washes did work perfectly.

Today Stuart arrived and removed more of the old wiring.

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Stuart, doing another CNC upgrade wiring.

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The old 7k computer has been removed, leaving some buttons.  I might be able to use those. The computer enclosure might disappear too.  Not decided yet.

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The old CNC mill has lost some weight.  Those cartons are full of old parts.  Note that the floor has been swept.  Stuart was concerned that we might be infested with snakes, but it is winter here, so we should OK until the weather warms up.

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The rats nest is disappearing.

CNC Mill Upgrade -4

I removed the old XY & Z axis servo motors from the mill.  Each one weighs about 15kg (33lb).

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The old servo motors.  The X and Z were working fine.  The Y was faulty, but I do not know whether the fault was in the motor, the encoder, the controller, or the connecting wires.  I will put them on Ebay as 2 working, one for parts.

Then I removed the belt drive pulley off each motor.  There was a grub screw, which would not budge.  Assuming that it had been Loctited, I applied some heat, judiciously.  The grub screw came out, but the pulley would not budge, so a little more heat, and a gear puller.   Two of the gears came off, but one still would not budge.

I asked for advice, and I was loaned a different type of gear puller. (thanks Rudi).  This time, some movement of the gear on the shaft was noted, and eventually the last motor gave up its gear.

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This one worked.

The shaft of the old motors was 16mm diameter.  The new motors had 19mm shafts.  So I spent some time on the lathe boring out the gears to fit the shafts of the new motors.  The keyways of the old motors were 5x5mm, and the new ones were 6x6mm.  So, I borrowed a 6mm broach (thanks Stuart), and enlarged the keyways in the rebored gears to 6mm width.   The new keyways needed a lower profile, so some time on the mill and surface grinder  to reduce the thickness of the keys to 4.5mm.

That was quite a few peasant hours hours on the lathe, mill, and surface grinder, but the end result was good.

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The new servo motors, with the timing belt gears fitted, with keys in place.  I will set each motor in place on the CNC mill, determine the final exact position of the gear on the shaft, then indent the shaft for the grub screw.  Then, when I am sure that all is correct, the gear, grubscrew and shaft will be Loctited.

Another small issue was that the boss on the new motors was 5mm deep compared to 3.5mm deep for the originals.  So the mounting plate for each motor needed the recess to be deepened by about 1.5mm.

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I used a boring head on the mill to deepen the first one, but it did not produce a good finish, so the next 2 (shown) were deepened on the lathe, in a 4 jaw chuck.

Meanwhile, back to the rats nest in the electric control enclosure….

 

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The bare space top left is where the old servo controllers lived.  They were removed.  Then I spent a half day tracing each wire from the controller to the old servo, and removing it.  That produced a carton full of wires.  The rats nest is now a little less tangled.  A lot more of those wires will be removed as the job progresses.

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The new servo controllers bolted into position.  They are fatter than the originals, so a bit of rearranging was required.  The yellow box top right is the main spindle speed control (VSD) which is being retained.

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And on the right hand side, newly bolted into position today, from the top down, are the smooth stepper, the C11 breakout board, and two C10 breakout boards.   Awaiting some expert wiring.  (Stuart, are you reading this?)

 

Upgrading the CNC mill -3. Moving a threaded hole in steel plate.

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this is the new Y axis servo motor, sitting on its mounting plate, after the old servo has been removed

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Unfortunately the existing M8 threaded holes in the mounting plate are just in the wrong position for the new motor’s 8mm mounting holes.

So, do I 1. make a new mounting plate and assembly?   2. machine or file the new motor’s holes to fit the old plate?   Or 3. Fill the old mounting plate hole, then drill and tap new holes in the correct position  ??

  1.  seemed a lot of work   2. would have looked ugly and probably voided the motor’s warranty      3.  Seemed tricky, but I decided to give it a go.   If unsuccessful I could always revert to 1.

Filling the old holes.  Could have used steel thread and silver soldered it into place.  In retrospect, would probably have been the best option.   Could have used steel thread and Loctited it into place…. decided against, in case subsequent machining  softened the Loctite.   Could have filled the old holes with bronze, and drilled and tapped new threaded holes….   well, for better or worse, that’s what I decided to do.

The new holes impinged about 25-33% on the old holes.

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The old holes were bronzed.   I improved my technique as I moved around the holes.

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After cleaning up on the mill, the new holes were center drilled 

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Then drilled to size, and tapped.  revealed that the bronze did not entirely fill the voids. 

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I wondered if the bronze would accept a suitable degree of tightening of the M8 cap screws, but all seemed fine.   Note the jacking bolts, to prevent distortion of the weldment in the milling vice.

The bronze-steel sandwich did cause the tapping drill to wander slightly, but not enough to cause concern.  Next time I will try silver soldering in a steel filler piece.

Meanwhile, I have been removing parts and wires from the electrical enclosure.

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The servo controllers are removed.  Bit of a rats’ nest hey!  About 90% to go…

 

Installing the lathe gear

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I neglected to take a photo of the completed gear.  In this shot it is almost finished.

I intended to reassemble the spindle and its cluster of gears, spacers, and taper roller bearings myself, but after talking to an expert on the topic (Swen Pettig), I realised that sometimes it is better to leave surgery to a surgeon.

I gratefully accepted Swen’s offer to help.  In his working  life Swen had performed this task on many, many occasions.

Firstly Swen reinserted the taper bearing outer races in the headstock.  The lathe spindle is approx 80mm diameter and 800mm long so it is heavy.  After carefully cleaning, it was fed into the headstock, progressively loading the bearings, gears, spacers, clips and nuts, and moving and tapping them down the shaft as it was moved into place.

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Note the photo prints to remind us of the order of reassembly.  Board to protect the lathe bed.  Repaired gear laying flat.  Surgeons’ towels blue rags.

when it was all reassembled and tightened, the retaining disk at the chuck end was loosened, sealed with liquid gasket (Loctite product- cannot remember the name), and retightened.

Then Swen went through a lengthy process of checking the end play, using a dial indicator, tapping each end of the shaft with a copper hammer, and finally settling on 0.01mm of play.

Then we had a short test run at low speed, and he tested the end play again, with no change.

Then we set it running at 200 rpm, and went and had a cup of coffee for 20 minutes.  Came back and checked the bearings temperatures.   All cold, all good.

I reinstalled the external gears, the cover, etc, and took some decent cuts in some cold rolled bar.

All good.  Oil change soon.

 

German Battleship Helgoland – book review.

Seaforth Publishing, in association withThe National Maritime Museum Greenwich, is publishing a series of books of plans and history of famous warships, in this case the Helgoland.

GERMAN BATTLESHIP HELGOLAND

Detailed in the original builders’ plans

By Aidan Dodson

 

Wow!

I opened this large format, hardcover book of ship plans at midnight, expecting a quick flip through, and was able put it down 3 hours later.   But I will be returning.

The first 20 pages outline the development of German dreadnaughts and their wartime careers and fates, and a fascinating history it is.  The ship structure, armament, machinery (including engines), protection, pumping systems and damage control, and fire control are described in a degree of detail which was satisfying and not overwhelming to this non expert but interested reader-reviewer.

Then, all but 20 of its 144 pages are reproductions of the original builders’ plans of the WW1 German battleship Helgoland.   The plans are detailed, and beautiful and fascinating.  With original annotations in German, translated and explained in the margins.    The 940 x 290mm centre fold of the longitudinal section is just stunning!

Modelers, historians, ship aficionados, and anyone with a vague interest in battleships will love this book.  I certainly do, and eagerly await further volumes in the series.

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Front jacket

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Centerfold.  

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The German navy used triple expansion reciprocating engines rather than pay royalties to Parsons to use turbine engines.

CNC Mill Upgrade -2

The major components arrived this week, from China and USA.  Switches, and other components which go “ping” will be bought locally as required.  I am hoping that existing pulleys, belts, brackets will be adaptable.

The motors to drive the X, Y and Z axes are 1.2kW AC servo motors which can be connected to single or 3 phase power.  Each one weighs 6.7kg (14.7lb) .  From China, they are nicely finished.   Substantially shorter than the old servos which they are replacing and slightly larger diameter.  I am hoping that the slightly larger diameter will not cause major problems.

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AC servo.  There are 3 of these.  Kitchen knife to open the box and for scale.

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Old Y axis servo on the right, and the new AC servo left.

 

And each servo motor came with a controller and cables and connectors.

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And the electronics came from USA.

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C11 breakout board.

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C10 breakout boards x2

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And the Smooth stepper control board.  It is tiny, but the most expensive electronic component.

All up cost so far is ~$AUD2100, of which shipping is about 25%.

Next step is to swap over the servos.  The old shafts are 16mm and the new ones are 19mm.  I intend to machine the bores of the pulleys.  Hope there is enough meat  Tofu to allow that.

Cutting the Gear

Today Swen and I started cutting the gear.  Here is the setup.

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The gear was centered on the rotary table with an aluminium bush, which fitted the outside of an ER40 collet chuck.  The chuck had an M3 shaft which fitted neatly into the spindle of the rotary table.  3 bolts secured the gear blank to the T slots on the rotary table.

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This photo was taken after the setup was broken down.  Showing the M3 taper ER 40 collet holder, which I used to centralise the gear blank on the rotary table.

I started the mill conservatively at 200 rpm and a 0.5mm deep cut, but gradually increased the RPM to 450, and the depth of cut to 2mm.   Later adjusted to 300rpm, 1mm cut.

The CNC table performed flawlessly, with rapid advances between the 360/77º degree cuts (about 4.6º each tooth).  The feed rate was controlled by manually winding the X axis feed on the mill.

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We initially used water soluble cutting fluid, but changed later to raw Tap Magic, which seemed to work better.

As you can hear in the following short video, the cutter teeth are slightly off centre, but working well.  Didn’t quite finish the gear teeth in this session.  Some sparks later on, indicated that a cutter sharpening was required before the finishing run.  That will happen tomorrow.

The smoke is evaporation of cutting oil.

The setup will be left undisturbed by removing the gear cutter for sharpening.

I changed my mind about sharpening the cutter in the middle of the job, and continued cutting.

Instead, I lowered the spindle rpm, and the feed-rate.  The sparks stopped.  Maybe I was just pushing too hard, or maybe there was a hard spot in the metal.  Anyway, I finished the cuts.

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The finished gear cut.  Are those teeth looking a bit skinny at the peaks?

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Showing the setup from the operator’s view.  The CNC table worked brilliantly.

 

 

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Removing the burrs with wire brush and file.

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And testing the fit with a trial run in the headstock.  Thanks Swen, for helping (actually directing) the trial run.  The new gear on the left.

I made a video of the gear being rotated through 360mm, perfectly, but for some reason it will not upload.  (did upload eventually.. see below).    It looks perfect, with a tiny amount of backlash.   Full installation in a day or two.  I was quite surprised that making the gear to the specifications worked so well.

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Me, testing the backlash.

And afterwards, sharpening the cutter on the Quorn T&C cutter grinder which I made a few years ago.  An amazingly versatile tool.

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Just in case I need to make another.

The lathe headstock will be properly reassembled in a couple of days.  But I am finally feeling a bit confident about this job.

 

 

 

Not Antarctica Again! Groan…

For those readers who have not automatically skipped this post after reading the title, I had some time to spend on Google Earth Pro recently, and back to my area of interest, at the big black reflective rectangle 22 x 7km, photographed in 1999.  And the strange 300 x 150mm objects seen 2006 – 2007.

This time I went back a few years to 2002, and this line of objects caught my eye.

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This is Antarctica, Dec 31 2002.  The red, yellow and blue pins are 300 x 150m objects, seen 2002-7.  The big black rectangle is in the middle of the left hand cluster.   The area of today’s interest is the small red line to the left of the long red line.  The small red line, placed by me on the photo, is 20km long.   The next photo is zoomed in to the small red line…

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Still 2002, small red line. Those 21 black dots are 1km apart.  And there is another, to the right near the top of my red line.   Now to zoom in some more…

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Look at those shapes.  They are 300 x 300m each.  Similar but not identical to each other.  Exactly 1 km apart.

The black rectangle does not appear in these 2002 photos.

The co-ordinates are bottom right, so you can check this out for yourself.  What do those black shapes look like to you?   Unfortunately zooming in closer does not increase the clarity.

Now, do you want to know how I found this second row of objects?  This is where it gets even more interesting.

There appears to be a track or mark in the snow leading away from the big black rectangle, leading to the south east at heading 112º.  The track is 7km wide, the same as the black object.   I followed it on Google Earth, until it disappeared after 132km.  At that point on Google Earth I scanned the years 1984-2016.   And zoomed in and out.

And guess what!  That point is exactly where the row of 21 objects which are 1km apart, starts (or ends).   WTF?!

And just to complete this post, there is a site on YouTube which I have been watching with interest, called “Bruce Sees All”.  “Bruce” is an amateur astronomer with a decent telescope which he has been pointing at the moon, and making videos.  I have taken some screen shots, which I post here.  Hopefully this will stimulate some of you to go to the YT site and check it out for yourself.

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No scale unfortunately, but that white donut shape must be many kilometers wide.  And by the shadow which it is casting, it is way above the surface.  Similar shapes nearby.

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And look closely at all of the rectilinear shapes in this screenshot.  Square meteorites perhaps?

 

I will get back to gear making tomorrow, hopefully.

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