First core box

[Rainer]

Hello Steamboaters

this weekend I did some fine tuning at the engine base. I added some ribs at the bottom (not finished jet!).


I also rough designed the three main bearing covers:


Unfortunately I identified an overlapping of the column structure and the bearing cover screws. Here I used M8 screws for 13 mm flat spanner. I don't want to take the next screw size M6 because this looks to small for my opinion (This is not a question of strenght). Have no solution for this in the moment.

[87gn@tahoe]

That is looking amazing Ranier.

That Savery compound is owned by Dick Vennerbeck. He and Alan Gregg recently restored it from a rather sorry shape. He may be willing to take pictures and dimensions for you.

Lopez Mike might recognize the chap in these photos I took at the 2011 B&W Steamboat Meet:

[gondolier88]

Wesley,

A little beauty, and with radial valve gear- although Hackworth rather than Marshall's variant- a quiet and refined engine design. The drawings and some castings for Gordon Cheape's modified (simplified) version of the Savery Compound are available from Reeves 2000 here in the UK.

Rainer,

Your bedplate looks like it would support an Airbus A380 parked on top, does it need to be that thickness?!?! Also, I see you are basing the bedplate on large navy engine practice, but typical English practice, and indeed the method Savery used on the engine that you can see above, used a bedplate of flat section, with minimal but substantial bracing, and with the centreline of the shaft on or slightly above the top surface of the bedplate, with underslung main bearings. This reduces weight, and also COG in the boat.

Greg

[Lopez Mike]

At least in one picture I wasn't scowling. Sigh.
Mike

[Rainer]

Hey Wessley,

thanks for this "happy" pictures.

He may be willing to take pictures and dimensions for you.

Thanks for this kind offer. I got already the original drawings from 1912 of exactly this pumps. Hope to be able to redesign it from that. If I have any questions I will give you a toot.

[Rainer]

Rainer,
Your bedplate looks like it would support an Airbus A380 parked on top, does it need to be that thickness?!?!

This is exactly the German Navy design from 1902. My goal is to copy this in scale 1:2 ... even if I also know some possible improvements.
20 HP German Navy Design:

Savery...used a bedplate of flat section, with minimal but substantial bracing,

That's what you can see on the picture - but even the Savery has a heavy bracing underneath the flat bedplate... Please compare the total height of Savery and Germa Navy design! For me there is virtualy no difference.
20 HP Savery Design:

and with the centreline of the shaft on or slightly above the top ... reduces ... COG in the boat

That's tru again - theoreticly - my base plate is about 60 mm in height - but to take you arguments - on other hands with this design the fine Savery "sinks" under the floor plates and is not that visible for the spectators. And you have to kneel deeper (30 mm) to change the soft packing.

COG of my little boat will mostly be influenced by position of picnic basket, beer crates and girls. So no tanning on the foredeck and the boat will be in trim

[gondolier88]

This is exactly the German Navy design from 1902. My goal is to copy this in scale 1:2 ... even if I also know some possible improvements.
20 HP German Navy Design:

Savery...used a bedplate of flat section, with minimal but substantial bracing,

That's what you can see on the picture - but even the Savery has a heavy bracing underneath the flat bedplate... Please compare the total height of Savery and Germa Navy design! For me there is virtualy no difference.
20 HP Savery Design:

and with the centreline of the shaft on or slightly above the top ... reduces ... COG in the boat

That's tru again - theoreticly - my base plate is about 60 mm in height - but to take you arguments - on other hands with this design the fine Savery "sinks" under the floor plates and is not that visible for the spectators. And you have to kneel deeper (30 mm) to change the soft packing.

COG of my little boat will mostly be influenced by position of picnic basket, beer crates and girls. So no tanning on the foredeck and the boat will be in trim

That's both honourable, and understandable.

I can certainly see the practical advantage of the height gain from the point of view of access to the cylinder glands. However, Savery's engine above was a launch engine, as is yours, and was built to be as pleasing to the eye and as compact as possible to passengers onboard- they, as today, wanted a tidy, well designed, pretty engine that could only be seen as much as it had to be. The centreline of the shaft could also be kept low of course too. However, navy engines, in deep, round-bottomed pinnaces with heavy engine beds and no wish to pander to the demands of fashion and aesthetics could be over-engineered without raising eyebrows.

I have stopped tanning my beer on the foredeck too, it goes warm...!

Greg

[87gn@tahoe]

Ranier, where did you manage to find Savery drawings? Do you have any more Simpson Strickland drawings?

[Rainer]

Ranier, where did you manage to find Savery drawings ...

I got the drawings from "The Heritage Steamboat Trust" (GB).

You can find their homepage at http://www.steamboattrust.org.uk/cart/store/?np=12.

You can email to this people and ask for the Savery or other drawings. Some they have already as pdf. Other can be scanned by their service. All this for 2.5 Pound or so per page. In the moment I am still waiting (without hurry) to get more pump details scanned.

I am very happy about finding those helpfull people via google.

[Rainer]

... However, Savery's engine above ... was built to be as pleasing to the eye and as compact as possible...

Yes Greg

The Savery engine was developed at least 10 years later as mine (think about a 10 years old car). So it was for sure the finest and lightest end of the steam century design. And yes, if you have a close look to the drawings the complete structure is designed for light weight and high rpm. The casted parts are not made for economic forming but to ensure this light weight structure.

Have a look at the column structure too. Where the German Navy design needs heavy cross beams, the Savery just brought the main columns to an angle avoiding the lateral oscillation (That's what other designers did too at the end of the steam engine era - but here you have a good example...)

This German Navy engine had the focus on easy operation and repair by using conservative design and traditional building methods (my opinion).

And look what I had done with the good old Mills compound design in 1997. Even here I changed the proven low COG base with a new base plate to a reverse design