3/4" Scale J1e

[JBodenmann]

Hello My Friends
Thank you Andy, you are much too kind. Sometimes I think I have lost my mind. Most of this little baloney will never be seen. This booster is mainly hidden under the ash pan, and between the trailing truck wheels and frame. But I am having fun makin' stuff. This little booster engine is mainly all thumbs. It doesn't really have to work, just look cool. I am having a grand time making bits and pieces for little #5344. Next up will be the flexible steam lines to and from the booster. Also the air throttle down by the left side cylinder. I have made them before in 1-1/2" scale. And then the Standard stoker engine. I did manage to get a little more done on the Barco Low water alarm. The main body is pretty much finished up, and all the parts that will stick to it are done.
See You In The Funny Pages...
Jack

[NP317]

Aka the cover plates:
Well, that makes sense!!

Drooling still.
RussN

[Asteamhead]

Hello Ian,

Daniel sent me a CAD drawing of his pump and asked me to add this to this page. That drawing contains all necessary details and information.
Here it is
By the way I watched a video showing a finished pump working on steam, worked fine!
Best regards
Asteamhead

Hello Jack,
Well done (from the hands of the master of brass)
A photo of a batch of some 30 (German style) KT 1 working feedwater pumps of scale 1 : 11.3 (5 " gauge) may be of interest?
They were constructed, manfactured by means of CNC, assembled and tested by a friend of mine Daniel. Ready for sale in the near future ...
Our hobby is still alive!
Best regards
Asteamhead

MMmmm candy, I could use one of those on my not built yet BR55! Asteamhead, who do contact to acquire one of these?

Thanks
Ian

[JBodenmann]

Hello My Friends
The low water alarm masters are mostly finished up and mounted. Here is a bottom view of the trailing truck booster. The round cover is for the cylinder that engages the idler gear. The cover is mounted to what will be its feeder after the mold is made. And the last photo for today shows the parts for the booster. Most are mounted to their feeders. I have not quite figured out how to mount the main body. One of the challenges when pouring the rubber into the mold is to prevent trapped air bubbles. How the part is oriented in the mold has a lot to do with this. Sometimes holes will need to be drilled in the master to let trapped air out of certain areas. Time to finish this up and move on.
See You In The Funny Pages...
Jack

[djjh87]

Jack you and others on this site have amazing skills. And as you have said alot of us are self taught or learned from a mentor. There are many ways to get there and different skill levels. I am always learning and enjoy the challenge. Thanks Jim

[JBodenmann]

Hello My Friends
I have been working on molds for the booster, and Barco Low water alarm lately. Here is a photo of some of the mold boxes. These will contain the actual rubber mold. Although not as precise as a hard tooling mold, pretty good waxes can be made with this set up. The large box at the front will be the mold for the main body of the trailing truck booster. Then we have the masters for the cylinders, cylinder cocks, and cylinder head covers. Recent additions to the cylinder master are the bosses which will hold the cylinder cock actuating cylinders, and the bosses for the cylinder cocks. All totally unnecessary as this is just a dummy booster, but will add some interesting clutter. A good model has the more you look, the more you see factor. Especially a big main line locomotive like 5344 here. This booster engine will supply something for the booster steam lines with their flexible ball joints to connect to. These big steam lines run under the cab, and running boards to the front end of the locomotive. The steam line to the booster with its air throttle valve is on the fireman's side. The exhaust piping is on the engineers side. They are a prominent feature of the engine. As usual this little trinket has taken way longer than I would have thought. This often happens, as when you start something like this reality rears its ugly head and upon closer examination you realize this little rascal is more complicated that at first thought. This is how we learn.
See You In The Funny Pages...
Jack

[NP317]

Jack:
Quite an accomplishment!
Your projects take longer because you are careful, and also make molds for castings!
Non-trivial work. 'Delightful to see your process and results.
Happy Holidays!
RussN

[my2cents]

Jack: Do you encase your molds in wood? In your pictures it looks like wood blocks with wing nuts. I have heard of doing that with aluminum. Is there any issue with vulcanizing the rubber in the shoe if they are indeed wood. Like RussN stated it is enjoyable to see your process and results. There is always something to learn.

[JBodenmann]

Hello My Friends
First off, thank you Russ, and Merry Christmas to you all. Yes my molds are encased in wood. The cavity inside is cut slightly larger than the master. The master is then suspended in the box, on what will later be the riser, or feeder. Liquid silicone is then poured into the mold. I do not use vulcanized rubber. Vulcanized rubber is far too stiff for many of the parts I make. Silicone is very soft and can be peeled off of complicated parts and used again. This hybrid wood box, and glove method works very well, and allows pretty accurate wax making. This is not as accurate as hard tooling but is much simpler. Cutting the mold open to remove the master is the fiddly part. Cut the glove wrong...start over. Not a big deal as you can put the master back in the box, and re pour the rubber. When cutting open the rubber it's always good to have the parting lines where they won't be too apparent, like along the edge of the part. Like many other things, after doing it a while you learn what works best, and what doesn't work.
Happy Model Building
Jack

[rmac]

Jack, I've been following along for a while and only recently realized that all these fabrications are patterns and not actual parts. Then in this last post, it sounds like some kind of lost wax process is involved. I'm guessing that the whole procedure goes something like this:

1. Make the pattern.
2. Suspend it in the wooden box.
3. Fill around it with silicone.
4. Cut and peel the silicone away from the pattern.
5. Put the silicone back into the box???
6. Fill the silicone mold with wax.
7. Cut and peel the silicone away from the wax, which is now a duplicate of the original pattern.
8. Somehow surround the wax duplicate with plaster or something like that to make a mold for casting. In the same wooden box, maybe???
9. Melt/burn the wax out of the plaster mold.
10. Cast a metal part in the plaster.
11. Break the plaster away from the metal part.
12. Relax with a root beer.

Is that anywhere close to how it works? About how many times can you use the silicone mold? And why brass and not some cheaper and/or easier to work material for the original patterns?

This is fascinating!

-- Russell Mac

[JBodenmann]

Hello My Friends
Russel you are mostly correct. I don't pour metal. I leave that to the foundry. The material used to surround the waxes is called investment, and is water soluble. The investment is heated to almost red heat before the metal is poured in. This is done in a centrifuge to fully fill the investment. That is how such fine metal is achieved. Without heating the metal would cool too soon. After cooling the investment is dissolved with water.
Jack

[jeffsmith]

Jack, don't forget to mention that any moisture and molten metal will cause a violent reaction. Not good.