Rebuilt Bulleid West Country 3D CAD designed & mft in 3.5 in

[silverfox]

Re Cutting

Does a slower feed rate matter? I haven't got power feed so hand cranking is rather hit and miss on a steady feed rate

[Cro]

Looking good, certainly an interesting looking loco. A friend of mine who does rebuild/new builds is rebuilding a 5" one for "Cunard White Star" Originally started by Kevan Ayling of the Worthing Club and finished by the Bob Frost from Chelmsford. It is a monster but a beautiful loco and I've just supplied 4 new scale lubricators to give it a bit of extra on the running plates.

I've done a few sets of working top feeds for NM/WC locos but one one pair in 3 1/2" for a Britannia but we cast these with the caps on to just screw into the boiler as non working valves, just too small really to make working reliably.

Doing various bits at the moment to go on a 7 1/4" version which has working chain gear and all!

Look forward to seeing this come together.

Adam

[masahiraoka]

regarding the question from Silverfox on feedrate Andrew answers as follows:-

"Feedrate is quite an important factor and in production machining, it becomes critical to tool life and surface finish. There are recommendations in both machining texts and also material specifications.

Recommended chip per tooth, is the basic rating for determining feed rate of a cutter through the material and this varies on the type of cutter and also the size somewhat.

In the case of 15-5PH the chip per tooth is similar to austenitic stainless steel like 304, therefore for a small endmill below 12mm (1/2") diameter 0.05mm-0.08mm (0.002" to 0.003")per tooth seems appropriate.

so taking the information above about 15m/min correctly pointed) for 15m /min the RPM for a 10mm cutter is: 300 x 15/10 is 450RPM from this then we can take it if we are using a four flute cutter 450 x 4 x 0.05 = 90mm/min feed rate.

In our hobby situation, this tends to be rather academic as many people do not have power feed, also, even if they do they are of the electronic kind which gives no direct indication of the feed rate on the dial. More to the point, a steady feed rate so the cutter does not rub on the material and kept sharp and well lubricated is far more important than actual numbers.

P.S. My apologies for a simple substitution error in the RPM calculation, I see one keen-eyed person picked it up."



Adam 
you must have read my mind - we looked at your website on Friday and saw that you've done non-working top feeds for the Britannia in 3 1/2 inch which from all the photos I've looked at are the same as on the rebuilt MN/WCs - makes sense that they used standard BR parts.  Adam you've not priced the 3 1/2 inch top feeds on your website - would you mind sending me this via email.

regarding the lubricators we're thinking of making them realistic looking dummies that each incorporate a tank with drip feed lines to all the key lubrication points between the frames eg axle boxes, eccentrics, middle cylinder slide bars etc.
again i guess at 3 1/2 inch gauge it is too small to make these lubricators work as per full size practice.

I'd be interested in seeing any special parts you're making for the as-built 7 1/4 inch version that could also be used on a rebuilt version. 

ciao Martyn
  

[masahiraoka]

this drawing of whats going on between the frames gives you a good idea of the level of detail in Phil's design




this Youtube clip shows what Porsche are doing with 3D CAD and 3D printing

www.youtube.com/watch?v=ztWsivHGL54


ciao Martyn

[92220]

Hi Martyn.


That is a super 3D CAD drawing! Just one question if I may...what are the 2 yellow lines that run from top to bottom of the expansion links, on the right? At first I thought they were internal oil ways but then saw they appear to around the outside surface. Are they made up of a sandwich of parts?

Bob.

[masahiraoka]

Bob
The drawing shows an early CAD version of the running gear where the design of the expansion links was to be laminated from two plates and then silver-brazed together to form each half.
Phil subsequently opted to go for ‘single-piece’ halves which are now 3D-printed in stainless. So the yellow lines seen in the screenshot were representing the silver solder fillet which joins the two plates

ciao MArtyn 

[92220]

Hi Martyn.

Thanks for explaining that. I did wonder if it showed a 2-piece construction but I couldn't think what it might be. Now makes sense!

Bob.

[masahiraoka]

Here are some screen shots of the West Country after Phil has removed the "cheeks" on the cabin sides as I suggested in my post of 20th May.

Whilst I acknowledge that this might not please the rivet counters I for one think it looks a whole lot better without spoiling that heavy-duty SR Pacific look. Phil didn't have to move any of the fittings in the cab to achieve this.

The other recent addition is the big exhaust pipe covers that protrude through the smoke deflectors.

[masahiraoka]

Here are the latest screen shots from Phil. Further progress on the details that make the loco look full size include the buffers, handrails, clacks (which will work) and plumbing.

[masahiraoka]

apologies for the halt in posts.

over the past three weeks Andrew has been working hard on the streamlined Duchess so little or no progress on the West Country build front.

But Phil has continued with the design work on the engine and for aesthetic reasons coloured the loco in more traditional garb.

Meanwhile I've been coming up to speed on converting 3D CAD models into 2D drawings for manufacturing purposes. I'll have more on this in the next couple of posts.

Meanwhile here is an almost complete realistic looking loco  

[uuu]

Very smart...

...except I think I prefer the previous cab front.

Wilf

[masahiraoka]

I should add that it is my current intention to name the loco No. 34039. Boscastle.

I chose this name because one of my closest friends built a boutique pie manufacturing business called, naturally, Boscastle Pies down here in Melbourne Australia. 
Quite why he did so I'm not sure but i should find out.
I've always loved a great meat pie and when combined with SWMBO's home made tomato sauce i couldn't imagine a better Saturday lunch.

that said I've always had a passion for exploring the outer limits of the UK having explore the Scottish Highlands, the Western Isles, Orkneys and Shetland and the lake District so Devon and Wales seem obvious next choices.

Meanwhile here is a link to an excellent potted history of the loco.
www.gcrailway.co.uk/the-railway/locomotives/34039-boscastle/

ciao for now
Martyn

[masahiraoka]

Wilf
do i take it from your post that you're a convert to the "cheekless" cab?
If so i absolutely agree with you.

it will be a long argument when it comes time to decide which to actually build

[uuu]

Yes. It somehow looks tidier. But I can see that, having spent so much effort underneath to get the hidden parts to look like the prototype, it would be perverse to have such a prominent part different.

One side one way?

Wilf

[masahiraoka]

Wilf
i was going to suggest just such an idea, one side one way one the other.
i thought that might sound like sacrilege.
You’re right about tidier and that’s why I suggested it, the cut away cab looks “half finished” whereas the rest of the rebuilt loco looks perfect, akin to the BR pacifics and duchesses.
why shouldn’t we continue to improve the best designs from the past, the A1 trust is ie they always proclaimed they were note slavishly rebuilding the past.
martyn 

[andyhigham]

If you gave it the name and number of a non existent loco, either never built or scrapped, then it can't be wrong. It would be what could have been, not what is/was

[masahiraoka]

Andy
that’s an excellent idea. As it is I already have two fictitious locos in the collection, a Merchant Navy No. 35041 Anchor Line, and a Britannia No. 70055 R.A. Riddles.
So I’ll give the West Country the number 34111 the next in the series and could choose as a name a West Country town, something associated with the Battle of Britain or perhaps even Oliver Bulleid after the great man himself.

[osiris09]

You could call it Invercargill 😁😁 since that's where he was born. You know Kiwis and Aussies like to claim stuff. 🤣🤣

[dhamblin]

Perhaps a better name, as you're working on the rebuilt design, would be 'Ronald Jarvis'.

Regards,

Dan

[kipford]

I think Lynmouth falls off the tongue and ties in nicely with Lynton.