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I have just released a new book that is packed full of Stirling engine plans, kit reviews, and more. The main focus of this collection is the pop can engine. There are illustrated plans for 5 pop can engines, including a two cylinder engine, a walking beam engine, and a horizontal pop can engine. You will find more information here: https://www.createspace.com/3641366



Enjoy!

Jim,

"5 new groundbreaking designs by Jim Larsen"

"Ground breaking....really?

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Jim Larsen's original designs...
- Single Chamber Pop Can Stirling Engine
- Dual Chamber Pop Can Stirling Engine
- Walking Beam Pop Can Stirling Engine
- Horizontal Pop Can Stirling Engine
- Quick and Easy Stirling Engine

Original designs?.....Walking Beam engine?...really?

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Darryl (boydhouse)

Darryl,

If you are concerned that I may have copied your walking beam design, please rest assured that I did not. As you know, the application of the walking beam predates both of us and is used in a broad variety of applications from steam through Stirling. One of my original designs uses a walking beam. That is all. I have great respect for your engine design and would not steal it.

Please let me send you a copy of my book. If you are in the US I can get a copy to you very easily. I appreciate all that you do in the promotion of Stirling engines and would be happy to send you a copy as a way to say thanks and as a way to assure you that your design has not been plagiarized. Send me an email (jim@stirlingbuilder.com) with a shipping address and I will get a copy in the mail to you.

Thanks,

Jim Larsen

I never had any reason to believe you would violate my copyrighted "plans", I don't think you would do that.

It is not the question I raised. These "designs" go way back, before you and I were born (most of them anyways).

It's OK, I'm just being picky is all.

Darryl

Are they groundbreaking and are they original designs? Yes to both!

Here is where these designs break new ground: Currently all the popular pop can engines (such as The SFA Stirling Engine Project of Stephen F. Austin University, and The Easy to Build Stirling Engine by TheRecentPast) are cooled by cold water or ice. Running the SFA engines for any period of time usually requires a good supply of ice. The short aluminum bodies of these pop can designs creates a big thermal short and the ice is quickly melted. If more ice or cool water is not added the engines often (not always) overheat and stop running. I wanted to design a pop can engine that was easy to build and did not require ice or water cooling. As a result, 4 of the original designs in the book are air cooled. The introduction of air cooling in a pop can engine is the primary innovation of these designs. There are many air cooled hot-air engines built in machine shops, but to my knowledge these are the first pop can engines to be reliably air cooled.

The Quick and Easy Stirling Engine was designed at the request of Dr. Dan Bruton at Stephen F. Austin University. He has been using the SFA design for several years and found that it was taking students about two weeks to construct the enigne with a success rate of only about 50%. He asked me if it was possible to design a pop can engine that students could build in a single three-hour lab session. The answer to that request was The Quick and Easy Stirling Engine. He is using it with his students this year in the Engineering 112 course at the university. This design has streamlined and simplified the construction process so that students are no longer overwhelmed with a long complicated construction process, and they should be experiencing much more success.

Are these designs original? Of course they are! Just as your walking beam engine is your original design for a hot-air engine, these are the hot-air engine designs that I created. I am not inventing the hot-air engine or the Stirling cycle. But I am using those principles in my own fresh designs for engines made with pop cans. As far as the walking beam engine goes, I made an effort to make sure my work did not copy your design. Some of those differences include a completely different motion ratio in the walking beam, the use of air cooling, the use of a helium balloon as the drive mechanism, the use of aluminum cans as pressure chambers and displacers, and the use of fine guage music wire for some critical moving parts.

So yes, these are ground breaking original designs by Jim Larsen! We can't re-invent the wheel, but we can all find ways to make it turn better.

Air cooled Walking beam engines made from cans are not new. Seeing you tried to school me on this fact already, you should already know that.They are not a "new" design. They have been around for a very long time along with the water cooled versions. The very first one I have ever seen was air cooled.

Stirling discovered the "concept" of the Stirling cycle

Others came alone and produced designs using those concepts.

You and I came along and modified those designs to make unique or original "plans".

Each of your "designs (five I think it says) are unique from each other. They each use the concept first discovered by Stirling and then perfected by others in their designs. as the years progressed.

But, yours and mine (Walking bean engine) are not original designs by any stretch. They are "a design" made by others and altered (by us) and made into a set of "plans".

Now if you would like to pretend you invented the walking beam can engine (air or water cooled) that is your right. But the design is not yours. I give credit to those who made the design.

You can't make the wheel "better" and say you invented the wheel.

Darryl Boyd

I think we agree on the principles and are simply offering our own interpretation of the vocabulary used in the sales pitch on the back cover. I am not claiming to have invented anything! I agree, we both have original plans. Neither one of us invented the Stirling cycle or the hot air engine. Please don't think I am even attempting to make that claim.

Let's stop judging a book by its cover get on with having fun building engines! My offer still stands. I would like you (Darryl) to receive a free copy of the book.

And for anyone else who is interested you can use this discount code and receive 15% off the MSRP: BX5U8S3E
I have adjusted the discount codes so that code will work on all three titles currently for sale at the Stirlingbuilder website: http://StirlingBuilder.com

Agreed!

Darryl