3/4" Scale J1e

[JBodenmann]

Hello My Friends
The New York Central J1e's had Barco low water alarms. This water alarm worked by utilizing a float in a chamber mounted outside the boiler. Here is a photo of a 1-1/2" scale alarm. 5344 is 3/4" scale so now one half this size will be needed. As masters for molds will be made, things like PVC plastic and body filler can be used. The first part to be made was the cylindrical main body. This is a simple brass turning. Then some 1/2" thick PVC was needed for the odd shaped part of the body. The only PVC on hand was 1/4" so two layers were glued up. Now I often talk about using what was laying around. This does not mean compromising the end product. If nothing "laying around" is suitable, something will be purchased. So the PVC was glued up, and sized using the mill. PVC plastic was used as this odd shaped part will be shaped mostly by hand using files and sand paper. As the glue was setting up, some other parts were made. The boss for the plug on top, and some bosses for fittings on the end of the odd shaped bit. All simple turnings that will just be glued in place. I'll have some more pictures next time.
See you in the funny pages...

[Berkman]

Curious if for something like this 3d printing in stainless or shapeways lost wax offering would be a good route ?

[JBodenmann]

Help My Friends
Berkmnan is correct. This would be a great detail to 3d print. IF you know how to do that, which I do not. I think the future of model building lies somewhat in that direction. But making parts, and finishing a locomotive are two different things. I'm a Luddite, give me a pencil, some brass, and solder. And, sometimes as we have here, plastic, for this is just a master to pull mold from. Today we are starting the odd shaped bit that would hold the float mechanism. This is made from PVC plastic, as this soft material will shape easily with files and sandpaper. Then a large end mill was used to cut a recess for the disc shaped part of the main body. The bottom photo shows what will become a mounting flange for the warning whistle and bottom connections. There are seven, yes seven T bolts and nuts that hold this in place. There is a large gap between two of the bolts. This is for the bottom connection as you will see later. The outer flange has holes for the T bolts and the inner flange has slots. Here the nuts have just been sat in place to have a look, and to determine how much room is needed for the bottom connection.

[JBodenmann]

And now over to the rotary table. The seven holes were center drilled and then drilled #56 for the #00-90 T bolts. Then the outer flange was parted off as in the third photo. The remaining part was put back on the rotary table and the slots for the T bolts were made. A 3/64" end mill was used to make the slots. Now it's time to start fitting things together. Solder for the brass parts, and epoxy for the plastic. There are three feet that studs pass through to hold the alarm down to the boiler. There are also some dummy fittings for 1/16" and 1/32" connections. A couple dummy valves and some tiny little valve handles. The valve handles may be a bit of a challenge. Lets see what I can come up with.
Happy Model Building
Jack

[Greg_Lewis]

Amazing, Jack.

So the question is: How many of those end mills do you break in a week?

[Mountaineer]

Love the hold down finger!

Mountaineer

[JBodenmann]

Hello My Friends
Thanks Mountaineer. That hold down was made just yesterday. All the others were too large. This one had to fit between the bolt holes. Usually they are crudely made in a mad rush, I took my time and did a nice job on this one. Something new, the other end is unfinished in case something special is needed in the future.
Thank you also to Greg, tiny end mills require a gentle touch. I don't recall breaking any new ones. Usually tiny end mills work fine and don't break if they are new and sharp, which this one is. All my end mills start out as brass end mills, in the brass end mill drawers. After they get a bit dull they go into the steel end mill drawers. The milling machine was wound up as fast as it would go, 4200 I believe. Then light cuts were taken. The material to be cut was .040" thick and two passes were made. Easy peasy. Brand new end mills and free machining brass is a wonderful combination.
Here is a photo and a drawing. I thought you might like a better look at a low water alarm. This is an oddly shaped little fellow. That's why some PVC plastic was used for the odd shaped part as it's much easier to shape than brass. Today some sandable primer will be shot on and filling and smoothing will start. I will probably have a go at the little valve handle too. These valve handles will come in handy later on. No shortage of things to do.
Jack

[JBodenmann]

Hello My Friends
Here is a little more on the Barco alarm. The usual making little pieces and sticking them together. In the top photo the two halves of the bolt flange have been stuck together with some #00-90 tee bolts and nuts just for a look. Then the parts for the whistle mount and test valve. You can see what the large gap in the bolt spacing was for. A frog was used to hold things in place during soldering. A 7/32" end mill was used to cut the hole to mount the flanged connection.

[JBodenmann]

Here is a far as progress has progressed at this point. Now we have things stuck together just for a look. The warning whistle just looks too small to me, so that will probably get re made. This is why things should always be test fitted. You don't want to find that something doesn't look right after it's all soldered together. The main body is getting some filler and primer to smooth things out. The mounting feet that hold it down to the boiler will be added. The Y bottom connection to the boiler with its dummy unions, the dummy angle union valve, and also the valve handle masters are still to be made. I had hoped to get most of this finished up yesterday but the power was off until well after dark. I hate it when that happens!
More to come.
Jack

[Bill Shields]

but Jack...you are a HIGH TECH Luddite since you use power machinery...

[Greg_Lewis]

... All my end mills start out as brass end mills, in the brass end mill drawers. After they get a bit dull they go into the steel end mill drawers.
...

What a great idea! Why didn't you tell me this 20 years ago?

[JBodenmann]

Hello My Friends
Once a cutter is used to cut steel its ability to cut brass or bronze is diminished. Same thing for hand files. They all start out as brass files with red handles. They also get a date written on them.
Jack