Author Topic: The Call of Cthulu...  (Read 1780 times)

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Offline Doddy

Re: The Call of Cthulu...
« Reply #15 on: Feb 09 2020 13:34 »
Thrust Buckets. These are the method that commercial jet liners use to brake after landing. Given the potential for a similar use - do I fit them?

Reversing! It will have to be towed back to the start - so a small shunter is required to do this. The Princess Royal required one for the same reason...

Thrust buckets and reversing? Theres always as reason to behave like in real life . . .  :)

https://www.youtube.com/watch?v=-Zkxh903s_w
"You don't know what you don't know"

Offline Doddy

Re: The Call of Cthulu...
« Reply #16 on: Feb 09 2020 14:03 »
Reversing! It will have to be towed back to the start - so a small shunter is required to do this.

Yup! https://www.youtube.com/watch?v=saG-QQSiG4I
"You don't know what you don't know"

Offline John Branch

Re: The Call of Cthulu...
« Reply #17 on: Feb 09 2020 15:35 »
Nobody thought to mount the engine pods on a turntable!? Braking and reversing solved at a stroke.
John

Offline Spitfire2865

Re: The Call of Cthulu...
« Reply #18 on: Feb 10 2020 13:26 »
Any reason you cant fit a motor for braking/reversing?
Belt driven, doesnt need much torque and can be actuated by a servo?
-Trevor Young

Offline Peaky 556

Re: The Call of Cthulu...
« Reply #19 on: Feb 10 2020 13:50 »
One of the first things you’ll need is super-elevation, and I mean super-super camber on the curves!
Thank you,
Tim
Facebook.com/AppleTreeRailway/

Offline cabbage

Re: The Call of Cthulu...
« Reply #20 on: Feb 10 2020 14:37 »
Tim,
There IS and easier method of ensuring good track adhesion and this was mooted in the pub yesterday.

"Why don't you tilt the train?"

The person who suggested this was duly castigated verbally (Martyn is ex RM). But again the idea has merit! This could be done using "saddle curves" in which one side of the loco is raised as the bogie rotates. A far simpler solution than pneumatics!!!

Having a donkey engine to pull the loco backwards rather than having a shunter is I feel "cheating"(?)

So far we have to construct ; thrust buckets, disc brakes and saddle curves -and the motors haven't even arrived yet!!!

regards

ralph

Offline cabbage

Re: The Call of Cthulu...
« Reply #21 on: Feb 15 2020 08:51 »
After some plotting and hmm(?) work production printing has begun. The jet shroud has been modified to fit the available fans and the wall shell thickness increased from 2 layers to 4. This gives me more to sand smooth. Printing of this should finish Monday morning. The top and bottom rear parts of the jet pod have been printed (12 hours each!) The next problem is the thrust buckets and how they angle into and out of the thrust stream. More cheese cobs and a pint afterwards -I think!!!









Regards

Ralph

Offline cabbage

Re: The Call of Cthulu...
« Reply #22 on: Feb 16 2020 08:46 »
Well after 25 hours 9 mins of printing the shroud body is complete. It is huge!









More OpenScad!!!!

Regards

Ralph

Offline cabbage

Re: The Call of Cthulu...
« Reply #23 on: Feb 16 2020 15:17 »
Printing is complete for the jet pod -other bits await programming. Looking at the completed jet pod, I am reminded of something  CJ Walas a member of another forum once said;

"Mr Brades, over the years I have come to realise that you are the most dangerously sane person I have ever known"...

He could be right(?)









" The only difference between me and a madman - is the fact that I am NOT mad."
(Salvador Dali)

Regards

Ralph

Offline John Branch

Re: The Call of Cthulu...
« Reply #24 on: Feb 16 2020 15:45 »
That pair of pods just looks "Right".  Going to add reheat?

John

Offline cabbage

Re: The Call of Cthulu...
« Reply #25 on: Feb 16 2020 18:43 »
John,

Thank you!!! The mind scrunching required to program an object upside down whilst having only pictures of it  the right way up... The tear drop on the top of the pods is actually the case for the wing tip landing wheel. once everything is set solid  overnight -it is out with the P38 and start gap filling and sculpturing. The pod is 18cm wide by 25cm long -so when it sits on the loco -you will notice it.

I think re-heat is out though!

regards

ralph

Offline Doddy

Re: The Call of Cthulu...
« Reply #26 on: Feb 16 2020 19:04 »
Jet pod as used on the B-36Jet pod as used on the M-497 Black Beetle
"You don't know what you don't know"

Offline Doddy

Re: The Call of Cthulu...
« Reply #27 on: Feb 16 2020 19:23 »
I think re-heat is out though

Hmn, I also think its just a turbojet. Mind you, given it is a 1948 design it probably would need a hefty pair of smoke generators fitted.

More pics . . .









Once you have mastered the ducted fan technology maybe the NYC snow blower and Russian version would be on the cards - LoL  :D





By the way Ralph - a great piece of OpenScad work there - very impressive!



"You don't know what you don't know"

Offline cabbage

Re: The Call of Cthulu...
« Reply #28 on: Feb 17 2020 09:32 »
Robert,
I am sure that I have seen a picture of the russian loco with two carriages attached? Once I have made the Black Bug and completed another 2-NOL the technology may be there for more powerful smaller diameter ducted fans(?)

As to congratulations on OpenScad once I have figured out how to program the code for the Japanese loco...

Regards

Ralph

Offline Doddy

Re: The Call of Cthulu...
« Reply #29 on: Feb 17 2020 19:27 »
Robert,
I am sure that I have seen a picture of the russian loco with two carriages attached?

You're not wrong, I'd never seen it that way - but . . .


"You don't know what you don't know"