Member postings for Tim Taylor 2

Thanks to all for the welcome and Happy New Year!

Yes it's going to be an adventure. What I want to build is a single stage velocity-compounded Curtis type turbine with a two row wheel with reversing sector. I'm shooting for a wheel diameter of 2.5 to 3.0 inches, but it depends on how small I can machine the buckets and still maintain a reasonably accurate velocity angle profile.

Tim

Hi all,

Just joined the forum a couple days ago - I'm a recently retired reliability engineer with long term experience in vibration analysis, infrared thermography, ultrasound and laser based metrology technologies.

My primary interests are in model stationary steam engines, and I am in the early stages of designing a scale model steam turbine. My shop equipment consists of a 10x22 manual lathe and G0704 mill that has been converted to CNC, along with two 3D printers - Afinia (UP) H479 & H800, all set up in a corner of my garage.

Looks like a great site - love it so far!

Tim

Great post Turbine Guy!

I'm working on a design for a scale model single stage steam turbine. The wheel will be a Curtis type, two row with reversing sectors. I could go either radial or axial split on the casing, but am leaning toward axial split as it will be much easier to assemble. I haven't finalized the wheel diameter yet, but it will likely be 2.5 to 3.0 inches.It's kind of governed by how small i can make the buckets and maintain a somewhat efficient profile. While it is a scale model and I'm not really concerned with overall efficiency, I would like to keep the water rate somewhat reasonable...

Looking forward to the next post in your series!

Tim

I have both SheetCam and LazyCam and have used A3D DXF export for some simple parts just to test it - works OK so far.

Tim

I have seen some inductive proximity sensors that will repeat very accurately, but they are also kind of expensive.

Tim

Which is part of why I changed my mind. The main reason though is that with E-Stop, nothing will move until the switch clears, while with axis limits, Mach3 can be configured to allow subsequent reverse axis movement away from the switch.

Tim

I use sealed micro-switches on my converted G0704 mill. They are used to home to min-X, min-Y, max-Z in machine coordinates. Since you would rarely, if ever, mount the part to be machined at physical home on the table, accuracy of a few thou is plenty, as you have to zero to the part before machining anyway....

For John's application, his solution is simple and reliable. My only real concern would be having the BOB input directly exposed to the environment - I would probably run it through an opto-isolator......

Tim

Just finished redesigning and downloading limit/homing switch mounts for my G0704 to my 3D printer.

While Mach3 does a pretty good job keeping track, it's nice to have real physical homing capability.

I'm also adding an adjustable switch for the Z axis that can be set to limit the low end of Z axis travel to avoid vise, fixturing, etc. Initially I was going to put it in series with the E-Stop circuit, but on reconsideration I think I will put it in the Z axis limit circuit.

Tim

Greetings to all!

I am brand new to this forum, but have been using Cubify Invent for several years to design 3D printed fixturing for laser applications. After playing with the eval version for a week or so, I recently upgraded to Alibre Atom3D.

Atom3D is different enough that there has been somewhat of a learning curve, but I'm getting there. Most of the tutorials I've found online were created for Design and reference some features that are not included in A3D, but for the most part. I've found some good information here that has helped.

I just completed my first assembly, which is a rotating adapter for my fly tying vise. I don't remember if it was mentioned previously in this thread, but even though A3D is very versatile in aligning parts, drawing the part in the axis it will be in relative to the other parts of the assembly makes it a lot easier.

Eventually I will be using it for the design of a scale model steam turbine that I want to design and build.

Tim

If it is still accessible, you may be able to archive a site using wget and save copy to your own PC. It runs in a command prompt and is not for the faint of heart, but includes pretty good instructions and examples.

Tim