Hydrostatic Lubricator Casting Source

[daves1459]

Can anyone suggest a possible source, lost wax or otherwise, to make casting of the hydrostatic lubricator condenser as shown in the attached sketch? I'd like the casting to be brass and to be able to polish the "bulb" portion after machining is completed. Most dimensions are negotiable if necessary.

Thanks, Dave

[Fender]

Might be a good candidate for an RP part 3D printed in metal. Shapeways offers this in a bronze/stainless matrix, if you can provide them the STL file.
Search for “steam siphon” on the www.shapeways.com web site for a similar part.

[ccvstmr]

At 1" OD...why not spin two halves out of brass round stock and silver solder the pieces together? The hex can be machined using an indexing head in a mill or something I've used...a 5C hex block in the mill vise. Polish to finish. Just offering an alternate idea. Carl B.

[Dick_Morris]

It looks like it would be a challenging casting to make with a hollow center and .078 wall thickness.

I'd probably machine it in two pieces, with the break as shown in the modified sketch. A stepped section on one end would make it easy to locate for silver soldering. The step would be machined off after the two parts were soldered together. If one didn't have a better way for forming it, the inside radii could be done with a 13/16 ball end mill which would give a slightly thicker wall. It looks like the end mill could be purchased for about $65.

I wonder how much is gained by having a spherical opening inside versus just drilling the .188' hole to the top of where the sphere is shown and leaving the rest of the sphere solid. This may be one of those instances where you can't scale nature.

Here's an interesting idea - How about making it from copper starting with a 1" diameter hollow copper ball? If I read the tables right, copper is three times as conductive as brass. http://www.necopperworks.com/copperballs.html

[FKreider]

Nice sketch! I like the mock-up of the completed assembly on the backhead of your engine, that's going to look neat when completed!

I could not resist drawing it in my 3D CAD program:

A little tricky to render but it came out OK:

I think it is possible that the part could actually be made by traditional sand casting with use of a core. This is likely how the originals were made.

[FLtenwheeler]

It could also be cast in 2 pieces and soldered together.

Tim

[daves1459]

Thank you all for replying and your excellent suggestions. I had thought of machining the parts and then soldering. Although I was unaware of the availability of hollow copper spheres. The spheres eliminate the problem of creating the outer surface contour of machined parts. I can envision a four part assembly silver soldered together, then blend all joints followed by brass plating.

Via PM I have received two offers to make a casting. I'll pursue that then decide to go the casting route or fabrication using your suggestions.

Dave

[ChipsAhoy]

I know nothing about the Hydrostatic lubricators. Does anyone have a useful schematic, which might be posted here, that may help those in the same situation as I? Is it mainly for external running gear, or can it be used on cylinder valves?
Scotty

[NP317]

To create the hex portion of the bottom or the part you could start with a piece of correct size hex stock,
bore it to a slip fit on the bottom part of the device, part it off, deburr it and solder it in position.
RussN

[Dick_Morris]

I have received two offers to make a casting.

I hope those who offered take and post some photos of the process.

[jessebanning]

We will be offering our working hydrostatic lubricator in early 2020

https://www.youtube.com/watch?v=hqWD1CKNMpY

https://www.youtube.com/watch?v=OGths6wONbQ

[NP317]

Well there you go!
RussN