Bob J's No.21 Steam Engine - Plans and STP Files

My dad scratch built a nice little single-cylinder oscillator many years ago.

It is a relatively simple design, but looks nice, and so I thought I would post it here for those who may want to build it.

This was the first engine I created a 3D model for back in 2011, and this was a good exercise for me to learn how to create 2D drawings, 3D models, and document model engines in general.

I really did not have a good grasp of how to 3D model, and so I just stumbled through this design.

More 3D design.

A few more screencaps.

In the process of documenting this engine, I mapped out what the difference was between the 2D program I had been using with my new 3D parametric design program (Solidworks).

Sometimes you have to put things on paper to be better able to understand the process.

The drawings I made for this engine in 2D CAD are not related to each other dynamically, and so if a change is made to one part in 2D, one must be very careful to update every view of that same part, and also one must update any part that mates with the part you changed.

With 3D modeling, if I change a part, all of the views of the part in the 2D drawings automatically update to reflect that change, and by viewing the assembly, I can tell how the changes affect mating parts.

Everything in 3D modeling emenates from the 3D models of the individual parts, including the Bill of Material, the Exploded View, the 2D drawings, the motion study, etc. Any change in any model is automatically and dynamically changed in every other entity, most importantly in the 2D drawings.

3D modeling is a quantum leap in design power, and I have likened it as ranking in importance in the design world to things like the creation of the wheel, or the creations of computers themself.

Here are my 2D drawings for my Dad's No.21 steam engine.

These drawings are laid out for a barstock build.
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A few more drawings for my Dad's No.21 steam engine.

A fellow named Julius De Waal found my No.21 drawings, and created a new set in metric I think, which are shown below.
Julius added a bit of bing to this engine, which was not my dad's style, and is not my style either, but he made some nice looking drawings.

I often see people on GrabCad and other places give Julius credit for my dad's design, and credit for my drawings, but the copyright is with me, not Julius, despite what you see on Julius's drawings.
You can't re-copyright something that already has a copyright on it.

I also used this engine design to try my first 3D printed part.
I ended up filling the frame print, to give the surface a convex shape, and keep it from looking so flat and plain.

This was my No.21 frame pattern.

And I decided to build a foundry in 2011, and this was one of the first items I tried to cast in 356 aluminum.

This was a very crude attempt at casting an engine part, but considering it was about the 3rd item I had ever cast, it turned out pretty well in my opinion.

I had no idea what I was doing when making these castings, but the way to learn is to try, fail, try again, fail again, and continue trying until you succeed.

Nobody ever got an engine built by giving up when things didn't go right.

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As luck would have it, my copy of Solidworks has stopped working today.

I will have to try and restore it, but that may not be an easy task.

Solidworks is very touchy about reloads, and I have had to get on the phone with them to get it approved in the past, such as when a computer crashes.

I will be back, hopefully with some STL files.

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Ok, I was able to reload Solidworks.
Not an easy task, and it requires license transfers over the net, and some serious sweating while hoping the transfer goes through.

Here is Part 1 of the STL files for Bob J's No.21 Oscillating Steam Engine:

Here is Part 2 of the STL files for Bob J's No.21 Oscillating Steam Engine:

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Here is Part 3 of the STL files for Bob J's No.21 Oscillating Steam Engine:

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Thanks for posting the design.

I would suggest that if you're going to supply 3D CAD models, post them in .STP format. .STL is for 3D printers and most CAD software that I've used doesn't really open up .stl files that well.

RJC

verdenstein-
Thanks for the heads-up.

I have not posted any 3D files on a public forum prior to this, so this is new ground for me.

The file extensions have always confused me, but I will try to keep up, LOL.

Here are .STP files for Bob J's No.21 Oscillator Steam Engine:
(Part 1)

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Edit:
This site will not allow me to upload .STP files.
I will have to upload these files elsewhere.

I will post a link in a minute.

https://www.classicsteamengineering...s-no-21-steam-engine-a-tutorial-by-admin.927/

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GreenTwin .​

Thanks for sharing !

GreenTwin said:

A fellow named Julius De Waal found my No.21 drawings, and created a new set in metric I think, which are shown below.
Julius added a bit of bing to this engine, which was not my dad's style, and is not my style either, but he made some nice looking drawings.

I often see people on GrabCad and other places give Julius credit for my dad's design, and credit for my drawings, but the copyright is with me, not Julius, despite what you see on Julius's drawings.
You can't re-copyright something that already has a copyright on it.

Click to expand...

Hmmmmmmm - - - - aiui if he's added bling and changed the measurement system he's likely fulfilled the requirements for 'substantive changes'.
Not what you want to hear but - - - imo - - - these kind of 'games' means that truly retaining the rights to something is only as possible as the amount of funds one is willing to spend maintaining those rights. (Interpretation - - - your rights will be held only so long as you spend buckets of money in the legal system (your lawyer will become your 'friend' very quickly!!!!!).) The only right you have is to not offer the item to the public. It seems after that everything gets murky real fast!

Nice work!!!!

Some days I wish I had the money to use something like SolidWorks and then I remind myself that I would have to run windows which now won't even really function well if air gapped and then I realize that that wishing just isn't going to happen!!!!

For me is it not so much about copyright issues as it is about getting credit for designs.

An example is De Waal's drawings of my dad's No.21.
There are perhaps 10 or more Grabcad No.21 models on display, and they all reference De Wall as the designer/source, which is false; my dad designed that engine, and I created the 2D drawings for it.

So De Wall is sort of highjacking other people's designs and drawings, and in my opinion, taking credit for other's work.

If you have ever documented an engine, you know it is a tremendous amount of work to create accurate 2D drawings.

I open-source many of my drawings so as to promote the hobby, but each of my drawings states "for personal non-commercial use only".

I don't really think it is cool for people to abuse this, and I consider De Waal out of compliance with the "non-commercial use" thing, because he is using my drawings to advertise his drafting services.

I don't consider drilling holes in a flywheel "substantive changes", but I do understand your point.

There are multiple De Waal engines on Grabcad that used my drawings, besides the No.21; this is a recurring thing.
I have complained to De Waal and the person running the website that posts his drawings, and asked them to give me the proper credit when De Waals uses my drawings.

I am not a naive person, and I post drawings on the open net with the understanding that there are De Waal type people out there in the world.

For this reason, I don't publish any of my complex designs on the open web, which is a shame because it hurts the hobby guys who just want to build engines.

I did post the green twin build with complete drawings in Live Steam, and those drawings are everywhere now, but copyrights still apply to those drawings. If the green twin drawings show up in a De Waal knock-off, chances are me and the Live Steam publisher will get a lawyer involved. Enough is enough.

It is what it is I guess.
I do track who is using my drawings, and I do send them emails if they start abusing the system too much.

One guy on GrabCad decided to remove his 3D model completely rather than give me credit for the design.
I don't understand this mentality.

Why not give credit where credit is due?
These designs and drawings don't fall out of trees; somebody has to spend a great deal of time creating them, and then has to be gracious enough to share those drawings with others.
Don't look a gift horse in the mouth as they say.
Asking for credit for drawings is not exactly asking for much.

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