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[Jerry C]

I’ve absolutely now idea what all the additional gobbledygook is in the text. Can anyone fix it?
 Jerry C.

[Jerry C]

There’s got to be an easier way!


Jerry C.

[Jerry C]

The last two days I’ve been working on the crankshaft. It’s  a rough casting with a squareish lug on each end. The two faces adjacent to the shaft are at right angles to each other and it’s relatively easy to mark the shaft centre axis on each lug. From this mark I drew two lines at right angles corresponding to the two journals and scribed a radius equal to the throw of the cranks with a pair of marking dividers, then, centre popped all six centres.  I mounted the piece in my mill vice vertically and drilled all three centres on each end with my largest centre drill.  Making substantial tapered holes. The holes corresponding with the crank / journals blew through the lugs and I tapped these holes on one end M6 and screwed an M6 capscrew in one to act as a lathe dog. I put the centre drill in the lathe chuck and used the centre drill as a dead centre ( it rotates with the piece) and a live centre on the tails stock.


 






I didn’t Machine the shafts and centre journal in order to maintain rigidity while machining the crank webs themselves as [size=78%]much as possible in this arrangement but leaving the centre bearing surface and shafts until later. [/size]


[size=78%]I rearranged the piece and put one journal’s centres on the lathe and finished one crank. Then rearranged again and machined the remaining crank before finally machining the shaft and centre bearing journal. [/size]






That was the lathe work done with so I put the piece on the mill vice and machined the crank webs to size.


[size=78%][/size]


I’ve left the lugs on until I can  check everything ok when mounted on the bed plate in case more turning required
[size=78%]I’ve been running in the cranks with the conrods loosely attached tightening up as I go. Oil and Brasso as running in medium. Another hour running in tomorrow then I’ll mount it in the bedplate and run in the three bearings. [/size]


Jerry C.

[Jerry C]

That’s the bottom end completed. This morning I ran in the crankshaft to the bearings. All three sip oil and equally. Oil cups tomorrow then I start Stephenson’s linkage.








Jerry C.

[derekwarner]

Fair flying Jerry 


I have gone back to your August 20th images & the 6 x bottom ends bearing holes appear as tapped holes for studs
You tapped 11 x tapping's, so implies this 


So you must have a close shell tube spanner, small body open-ender?, or are they bolts & tighten the bottom end - otherside?


Derek


PS....how do you find the new Taig Mill?

[Jerry C]

Hi Derek, I have a set of cheap lazer cut combination spanner’s in BA sizes I get from Blackgates Engineering in Yorkshire. $12 a set. I grind the ring part to reduce their diameter and they’re perfect for the job. I’ve got two new sets lost in the post atm, plus a load of various 1 size under BA nuts and bolts. Their website is tedious but they’ve got loads of stuff. They specialise in narrow gauge locomotives and anything steam. So far I’m 45 days ahead of the last build which I put down to my new milling machine and loads of decent tools and fixings. I was schooner rugged for the first Stuart. I won’t build another Stuart, overpriced and poor quality control. Next one will be P M Research excellent quality, better drawings and a tenth of the price!
Thanks for watching.


Jerry C

[Jerry C]

Sorry Derek, I missed one of your questions. 5BA studs in the Soleplate and nuts for the caps. I don’t have a Taig Mill, it’s a Sieg SX2P with a large table. It’s brilliant. I got it from Ausee Tools in Melbourne. They’ve got everything at a little over Chinese prices.





This morning I knocked up three oil cups for the main bearings.





Then I started on Stephensons gear beginning with a pair of connecting rods. Using a piece of 3/8”x 5/16” mild steel I mounted it in the mill vice, using DRO drilled the holes for the 3/16” reversing shaft and the 7BA clearance holes. Then milled one side to remove the bulk of the unwanted metal. Tomorrow I’ll flip them an do the other side. I dug out the mandrel I made for the Twin Launch only this time I’ve got a rotary table. I leave the R/T mounted to the left end of my mill table and my precision vice on the other end which saves time swapping over.





Jerry C.

[Jerry C]

The previous photo showed two mandrels on the top of the vice. I forgot to take a photo of them in use but basically I bolt one in a hole and mount it in the rotary table chuck and put a broken drill through another hole to be driven by the table while I mill the bosses.





Using different sized broken drills to set the angles to get the tapered cut on the sides.
I use broken things like drills and endmills in place of gauge pins. Anything to get the job under control.


Jerry C.

[Martin (Admin)]

   
       

[Jerry C]

I manage one pair of drag links made out of the square but of a door lock that the knobs are fixed to. It was rock hard and was hard work. I can’t go out to get more because it means crossing the boarder back into ACT. It’s not with exposing myself to Covid and there’s plenty I can be getting on with until lockdown ends.


So, next, the Crosshead Guide plates. I was given a large sheet of 1/16” thick stainless steel plate but can’t find it. It must have got lost in the house move. What to do?  I found an old toolbox under the house and the padlock latch looked about right, measured it and it was just a fraction over 1/16” thick but galvanised and I could get the 2 pieces out of it. I  drilled out the rivets, ground off one end of the hinge pin and salvaged the flap. Used a hacksaw to cut the unwanted bits off and got the ends square on the belt sander. I removed the galvanising on a sheet of wet & dry paper. I gripped the stock in the mill vice on parallels. Using DRO I drilled the four 7BA clearance holes in the ends then chain drilled the slot undersized then ran a 2.5mm end mill through the holes followed by a 5mm end mill. (When I machined the crossheads with this in mind as it saved buying a 3/16” end mill). I didn’t square off the ends of the slot because the crosshead bit that slides in the slot is round. I think it looks neater. 
I repeated the process on the other side of the plate then sawed the pieces apart then, back in the vice together and milled the final edges to size.





The observant amongst you will see I got 4  countersinks on one side, just like I did on the Launch Engine. I knew before not to but things were going so well and the material was lovely to work that I forgot. It’s not a problem though because when to do them on the right side the plates are located by the c/s and not the clearance hole.


[size=78%][/size]


Everything lines up with the reversing bracket and the bottom cylinder covers so a result.





Next job, piston and valve rods.


Jerry C.

[Jerry C]

Yaaaay!! My parcel arrived from Blackgates!!!!  Ordered 30th July, sent 17th August arrived today 28th September.






Anyone not familiar with Blackgates catalog these are the Laser cut, stainless steel BA spanners. Cheap as chips and they work fine.


I boxed off the valves today. I haven’t followed the plans on these. They don’t allow the valves to float and get pressed onto the port faces by the steam.





Also I haven’t got a 1/8” end mill so I’ve gone metric.





Jerry C.

[derekwarner]

Evening Jerry...........certainly not familiar with the Blackgates offerings, but obviously laser-cut from a common thickness plate  , so are the smaller sized too thick?...or the larger sizes too thin?


As we know, the Knupfer laser-cut metric sized O/E spanners are certainly not Cheap as Chips



In OZ, we were taught the lower set of images as 'Crows Foot' spanners [but always thought the jaws were set @ 15 degrees offset, or 75 degrees off to the spanner shank axis?] 


Is that a universal name?


Derek

[Jerry C]

Common thickness yes but all get the job done and you can bend the grip to whatever suits. Let’s face it, not much torque needed for BA.
As for crows foot spanner’s, I’m familiar with the name but associate with these?

[Jerry C]

I knocked off a pair of valve rods and adjuster thingamagigs, made four gaskets and boxed off the valve chests. We start 14 days quarantine today due to both daughter and son in law being exposed to active covid cases. Makes no difference to me as I seem to live in the shed anyway. I’ve got music, a couple of chaired on wheels and a toilet. I just need a hammock.





Last job today, before dinner, was to mark out the expansion links, well one anyway. I’ll superglue two pieces of steel plate together and make two at once. My new spectacles  should be ready in Specsavers tomorrow. I could have done with them today as I had difficulty setting my dividers to 64ths”. Achieved it more by feel than eyes!


Jerry C.

[Jerry C]

I superglued two pieces together and mounted them on a mandrel in the centre hole of my rotary table and bolted a strap across them to hold The securely. I centred the table under the chuck and moved the X axis of the table using DRO and drilled three holes then chain drilled the slot. Then ran a 4mm slot drill to clean out the slot. Then milled all the extremities before freeing the pieces and putting them back on a mandrel through each hole in turn and milling around them.
 Today was a good day, everything went as planned and I made no mistakes. My best piece of work so far. I shall refer to it as my quarantine period.


The first pic shows the setup.








Jerry C.

[Jerry C]

I made a string of expansion dies when I built the twin engine. On this build I left the ends of the die slot half round rather than square as in the drawings. I filed the ends round to match. I think it’s an improvement.





I started on the steam pipe flanges. There’s not enough meat on the Pb blanks supplied to make the LP exhaust flange out of so I used some 7/8 bras round stock to make it out of. It looks as though there my be some conflict between the flange set screw on final assembly but I’ll manage somehow.





Jerry C.

[ooyah/2]

Hi Jerry,
When you come to fitting the lagging shields fit the exhaust side over the exhaust hole and bore it out and then the bottom screw can be slotted on the head which allows a much better fit than profiling around the exhaust flange.
If there is any leakage you can put a gasket underneath the shield and on the underside of the exhaust flange.
What happened to the mid post thats a bit out of line ?


Nice job so far keep it up.


George.

[Jerry C]

That’s 2 weeks quarantine done and dusted. No hardship as I live in the shed 9-18 daily anyway. I’ve been finishing off the last parts for the engine, the reversing lever and fittings were made when I did two for the Launch Engine. Drain cocks, crosshead guide plates and cladding all done plus a bit of painting, I went with the blue but used Bunnings cheapo paint at $5 a can with etching primer beneath. I broke my last 7BA tap so have been waiting for a new set from a model aircraft store in NSW, only $9 so winner there and came in less than a week! I got the 5/16”o/s copper pipe from an air conditioning suppliers and waiting on the 1/4”. Anyone know how to put 1/4” radius bends in 1/4” pipe. I’ve tried the ice method and the salt method and not been happy with either!











Yes, I know, countersinks in wrong sides. I was even aware beforehand but still did it wrong! Not a problem though as there’s enough meat in the plates to support the screws.




[size=78%] [/size]


I’d decided where possible to replace the 7BA grub screws supplied with 2.5mm socket head ones so I’ve been waiting on a tap for those which arrived just now, postie road down the drive straight into the shed and delivered. Turns out he’s a steam freak too and ahead of schedule so we had a natter.


I wasn’t happy with one conrod small end so made another out of what I thought was brass round bar but it’s some sort of alloy and machines similar to P/B but a slightly different colour.























Also while waiting for stuff I decided to build a condenser. My son in law found this, it’s a mixer control for a shower, made of P/B. I removed the buttons and bored out the inside as much as possible. I made a 20 turn copper coil mounted on a brass end plate with 1/4” ME fittings. I soldered this assembly on the open end and also a bottom plate to cover the button holes. Then made up the exhaust pipe and flanges. A bit of paint and that’s done. Plan is to take cold water from a tank with a pump through the coil then on to feed the boiler wit hot water via a bypass valve and back to the tank. Another larger bore pump will evacuate the condenser and also return to the storage tank. The entrained oil will float on the top. I’m picturing in my head a pair of pumps in a boxer formation on the eve of the crankshaft driven by a scotch crank.











Back to work.


Jerry C.

[Jerry C]

Today I installed an LED light ring around the spindle on my mill. So much better then two desk lamps cluttering up the bench.





I’ve almost finished the Compound engine. I’ve sold the Twin Launch Engine for the asking price and am meeting up with the buyer half way tomorrow to deliver.


I’m going to take my big boiler out of the steam launch and mount the compound on a wood table as a working steam plant. Need more copper pipe methinks.


Jerry C.

[Circlip]

Tight radius bends always a problem. Suggest filling with "Cerrobend" low melting point Bismuth alloy. Still needs idealy a bend former with a wiper die. Alternate, electro form.


  Regards  Ian.

[Jerry C]

Thanks Ian. 3/4” radius is the best my pipe bender can manage. Never had any luck with springs either. I’ll see what it looks like with 3/4” radius. It maybe ok.


Jerry C.

[Jerry C]

Yesterday was a good day, I sold my Twin Launch Engine for a very good price. Sold to a guy from Sydney, I love it when a plan comes together. It was on Market Place for yonks but I held my nerve (didn’t really need to sell). He wants the compound too but I won’t finish that until we return to Oz in November 22.  Also our flights home to UK booked for mid November. Canberra Sydney Singers and Manchester. We’ll have been here I’ve 18 months longer than planned. The only downside is we’ll have two winters on the trot.
Today I made up the HP exhaust pipe. The 1/4” o/s pipe arrived early today. I’d bought a pipe bender last week which does 3/16” 1/4” and 5/16 but not at the specified radius or even close. When doing the second steam launch I made my own bender for the small stuff but went for fittings instead. I made a pair of wheels on the lathe to give 1/2” radius and gave it a go. No success first time , bends we’re fine but dimensions cocked up as the piece moved. Solution superglue one wheel neared the stop. Second attempt successful. A few marks but that’s ok because it wil be lagged anyway.








Jerry C.

[derekwarner]

Jerry, whilst the Drawing may nominate 1/4" OD with a 1/4" radius, I suggest it is an improbability as a bend ratio for tube


In an earlier life I spent 10 years in shoreside marine hydraulic work [BHP Fleet Operations in Kembla]....100's & 100's of meters of replacement stainless steel deck hatch work hydraulic tubing...cold formed bends in 1/4" to 1 1/4" OD tube .....[or 6 to 30mm for European builds]


The Australian Standard for this work ratio of bend was r = 3 x diameter.....[this was just one of the engineering criteria as a delimiting  allowance for thinning of the external surfaces of the bend


[Other delimiting criteria were.....the UTS of the tube material, relief valve setting and WP of the of the hydraulic system, salinity of sea-water, temperature, Chlorine levels, velocity of contained fluid, corrosion allowance, cleanliness of internal fluid, type of fluid & ?>?>><><?>?<    ]


So one possibility in  your engine Drawings is that the original then scaled down engine stream pipe may have been a sand-cast bronze ....then machined at each end to cleanup


The engine looks superb ...I was hesitant of Blue, but the result   

[About the only thing I can offer is 1/8" square leather shoe lace ......yes, I have found a circular Superglued splice of the leather makes an excellent endpiece for the string + paste for the lagging - it sits squarely and can be filed, primed & painted to blend in with the lagging surface ]

Derek

 

[Circlip]

Yes Derek, EVERY arty farty "Designer" should be made to try to manufacture some of their flights of fancy.


  Regards  Ian.

[derekwarner]

With the greatest respect Ian, these early-day engineers & designers were pretty smart Blokes    ......so maybe the original Drawing Notes were not transcribed to the scaled down dimensioned Drawing  ....as "sand-cast bronze"?


Just a guess, but I would give the original designers the benefit of our doubt


Derek