Feldbahnmodule with ship

[fspg2]

@Russ
You could be right 


Today we are talking about the supports of the secondary and lifting bridges.

westl_Nebenbrücke_Brückenlager (fspg2)


Both ends of the west side bridge can be seen in the view above. In each case (circled in red) on the left the fixed bearing and on the right the suspected roller bearing.

But in the following drawing I don't see a roller bearing but a "bolt" in the middle....was that enough to compensate for the longitudinal movement of the secondary bridge :?: :?: :?:


Auflager_Nebenbrücke_03 (fspg2)



Auflager_Nebenbrücke_01 (fspg2)



The bearings for the secondary bridges resting on the two portals (shown as a red roller on the left) are soldered together from several milled brass sheets. Appropriate pins and grooves are provided for precise mounting. Similar to here at the harbor crane.


Auflager_Nebenbrücke_02 (fspg2)


The red base plate has a size of 15.7mm x 10.0mm.


The four replicas of the lift bridge's original cast bearings are created as 3D printed parts.

Auflager_Nebenbrücke_04 (fspg2)



As a combined block of four, they are a about €10 cheaper than four individual parts (despite the bulk price).

Auflager_Nebenbrücke_05 (fspg2)


The brass parts should be ready in fourteen days - much faster and a little cheaper bit than a well-known competitor from Holland.

[Bernhard]

Fascinating work, Frithjof. I have also found that making individual brass castings is cheaper than placing multiple parts on a sprue. Apparently weight also has a significant effect on price. Holes, for example, make a part more complicated, but also lighter and therefore cheaper.
Can you tell me where you have your parts made?

Bernhard

[Lawrence@NZFinescale]

My casting supplier levies a fixed charge depending on the volume of the part plus a metal charge of NZD 0.40/g (for silicon bronze).  For a casting this size probably NZD 8.00 or so for the fixed charge.  All up probably less that $20 - which is about EUR 12.

That does not include printing the 'wax' which I do myself.  The wax prints can be expensive if the caster does them.

It pays to make any modelled sprue as small as possible and have the caster add wax sprue - which they will remove after casting and thus not charge for.

[Hauk]

Fascinating and inspiring as always!

[finescalerr]

The comments are as interesting as the design. -- Russ

[fspg2]

Thanks you for the comments!

@Bernhard

Can you tell me where you have your parts made?

I ordered the parts here: https://i.materialise.com/de


The following zooming shows a small but important part for leveling the movable lifting bridge.

Nivelliereinheit_Gruppe_04 (fspg2)


I assume that the lifting bridge was brought into the appropriate position with the help of the two floating cylinders and the counterweights in order to align the rail joints with the side bridges.
Then the movable wedges were pushed into position and fixed to the base bodies with the nuts.
When lowered, the lifting bridge had a fixed support on the portal now.
However, I'm not sure whether the two contact surfaces were corrugated on the original, you could guess it from the sketch. I won't reproduce it in the model.

Nivelliereinheit_Gruppe_01 (fspg2)



Nivelliereinheit_Gruppe_02 (fspg2)



Nivelliereinheit_Gruppe_03 (fspg2)




It's amazing how many individual parts have to be installed in this portal carrier unit.

Portalträger_Einheit_01 (fspg2)


If you count, you will come up with about 185 parts.


The STL file has two extra parts... you never know where such a small, unique piece will go.

Nivelliereinheit_Gruppe_Druck_10x_1 (fspg2)


In 3D printing, the 1.0mm threaded rods are not printed, they are soldered in individually later.

[finescalerr]

Please be sure to post photos of the printed assembly when it's ready. -- Russ

[Stuart]

The detail and extent of accuracy you are expending on this project is phenomenal!

Stuart

[Bernhard]

Thanks for the info Frithjof.

I have another theory about the contact surface of the wedges: the upper wedge is guided on both sides in a groove. The broken line is the invisible contact surface. The line drawn above it is the upper edge of the lateral guide. The lower part is wider than the upper.
This is how I would have built it as a designer.

Bernhard

[fspg2]

@Russ
will be done!

@Stuart
This "rivet counting" is certainly sometimes exaggerated - but why shouldn't I build something as precisely as possible with my skills, especially since many detailed representations are possible on this scale (1:22.5).
With 3D printing, there is a minimum material thickness, which on smaller scales would reproduce the original far too strongly.

@Bernhard
Thank you very much for your hint! Volker had similarly considered this possibility.
So I adjusted the leveling unit accordingly:

Nivelliereinheit_Gruppe_06 (fspg2)


The new lateral guide has a height of 0.2mm (0,00787402 ") and a width of 0.4mm (0,015748 ").

Nivelliereinheit_Gruppe_07 (fspg2)


Nivelliereinheit_Gruppe_08 (fspg2)

[fspg2]

The four brass supports arrived today.

Auflager_Nebenbrücke_06 (fspg2)


When measuring, there was a minimal shrinkage of 0.6% - 0.9% - I can live with that. For the future I will print similar sized parts at 101%.
Because I had only planned one approach on the underside in the middle, the lower surface became slightly round. After cutting off the 1.5mm round attachment bars with a fretsaw, I was able to smooth the four supports on a sandpaper board so that everything appears flat again.
For the following similar parts, however, I will provide several bars accordingly, even if the fretsaw then gets more work.

Since my milling machine is not running at the moment, I used the time to draw other parts.
In addition, some of the many prefabricated individual parts are soldered. But the mountain is only slowly getting smaller.

Hubbrücke_komplett_09 (fspg2)


Träger_Montage_mit_Schacht_01 (fspg2)


Träger_Montage_mit_Schacht_02 (fspg2)


Träger_Montage_mit_Schacht_03 (fspg2)


Finally, there is a colored view of the lifting bridge during the construction period around 1899:

Hubbrücke_LEA-431_400-coloriert (fspg2)

Copyright: Lauenburger Elbschiffahrtsarchiv
(By clicking on the picture you get to the gallery. A second click enlarges everything.)

[finescalerr]

The castings look terrific, even if they are very slightly undersize. The bridge itself will be a standout model, something beyond the ability of most of us but always an inspiration. --  Russ

[fspg2]

Originally, I had planned to permanently install the lifting mechanism together with the portals on the module.
The module is built on a door leaf (202cm x 82cm) and will have a height of approx. 79cm with the portals.

Modul-Montage_43 (fspg2)


lift-bridge-operation-principle_02 (fspg2)


Schwimmer_61 (fspg2)



However, to protect the portals in case of a possible transport, I will make them demountable now.

So once again something was drawn.

Träger_Montage_mit_Schacht_12 (fspg2)


A box made of 5.0 mm HDF boards is firmly glued around the first version (see picture above). A 1.0mm MS58 sheet metal is then used as the basis for the portal. On the side, two 30mm x 15mm brass brackets are soldered to the sheet metal as a support.

Träger_Montage_mit_Schacht_08 (fspg2)


Next, another box (now 6.0mm poplar plywood to save some weight) is glued firmly to the module as a guide. This also gets two brass brackets as support for the removable gantry box.
Between the two boxes, there will be 1.0mm of air all around the sides to compensate for any expansion.

Träger_Montage_mit_Schacht_09 (fspg2)



Träger_Montage_mit_Schacht_11 (fspg2)



On the module itself, space was created and some already glued partition walls and Styrodur panels were cut out again.

Träger_Montage_mit_Schacht_06 (fspg2)

[finescalerr]

Well, then, it looks like the whole bridge should be finished in about half an hour! -- ssuR

[Barney]

Not that its one of the most fantastic piece of micro engineering I have seen in years or a life time - But Im completely lost and lost for words - but don't let me put you off just keep the Fantastic workmanship up - just looking at the workmanship that's going into to it - I surrender and I shall get on with my Lego blocks
Barney