The kit was purchased 35 years ago (1978) for $6.95 post paid, by my wife's father, presumably to build for her son (my step-son) who was 6 at the time. It sat on a shelf for years after grampa's death until I tackled it this year as a newbie to machining.
A Micromark 7X14 lathe and assorted accessories purchased for the purpose tilted the financial equation, severely offsettting the original purchase price of the quite simple set of parts.
The instructions were nearly complete. The diagrams of the rotary valve did not have any dimensional or angular information to describe the length of the grooves required for air passage in and out of the cylinder. I broke out a long unused drafting protractor and worked out the number of degrees of the two grooves from the diagrams and got lucky!
Fortunately the materials and design of the engine forgave many errors as my learning ramped up. In spite of my ineptitude it runs well on compressed air and I was pleased to deliver the finished product recently to my step-son, now 41.
A Micromark 7X14 lathe and assorted accessories purchased for the purpose tilted the financial equation, severely offsettting the original purchase price of the quite simple set of parts.
The instructions were nearly complete. The diagrams of the rotary valve did not have any dimensional or angular information to describe the length of the grooves required for air passage in and out of the cylinder. I broke out a long unused drafting protractor and worked out the number of degrees of the two grooves from the diagrams and got lucky!
Fortunately the materials and design of the engine forgave many errors as my learning ramped up. In spite of my ineptitude it runs well on compressed air and I was pleased to deliver the finished product recently to my step-son, now 41.
