Lamina Flow Stirling Engine Plans - Lamina 2


To see this engine running at over 1700 rpm check out the Lamina 2 - Lamina Flow Stirling Engine video.

Here is the video commentary:

This is the Lamina 2 Plans video. The base measures 9 inches by 7 inches and is about 3/4" thick. The Rubber Feet on the bottom of the base keep any surface the engine is on from being scratched by the one bolt that runs through the base. The flywheel support column is a piece of wood that measures 1 inch by 1 inch by 2 1/2 inches. The whole base has been spray painted with this textured spray paint. The center of the hole drilled through the flywheel support column is 1 3/4 inches from the base. The diameter of the drilled hole is 5/16ths (8 mm). I've glued 2 bearings into the support column. These bearings measure 8 mm X 5 mm x 2.5 mm. I found these bearings at Target, they are manufactured by Radline for RC cars. Target doesn't seem to sell these any more but I found another pack on ebay. Hobby shops are a good source for bearings as well.

The flywheel is made of steel and is 3 inches in diameter by 3/16ths thick. The shaft of the flywheel is made of aluminum. The thicker part that is attached to the steel disc is 1/4 inch in diameter and is 3/8ths long. The skinnier portion of the shaft is 3/16ths (5 mm) and is 1 and 3/8ths long. There is a small hole drilled in the aluminum shaft of the flywheel where the shaft sticks out of the bearing. A broken LED light serves as a cotter pin. There is a 1/16ths hole drilled in the steel that is 1/2 inch from the center of the flywheel. This 1/16ths hole allow a 0-80 bolt to fit through it. This bolt is 5/8ths long and also runs through this 1/8th inch square piece of rod.

This square piece of rod is 1/2 inch long and has 2 holes drilled through it. One hole is 1/16th in diameter for the 0-80 bolt and the other is 3/32" for the brass rod. The centers of these 2 holes are about 5/16ths apart. I glued this piece of brass rod into the square rod. The bearing that this brass rod fits into has a 2 mm inner diameter, 2 mm is slightly smaller than 3/32nds of an inch. I turned down a 3/32 piece of brass rod with a lathe. So this brass rod is 2 mm for 5/16ths of it's length and the other 1/8th of length is 3/32nds. I have since purchased some 2 mm brass rod through ebay and I found a 2 mm drill bit at harbor freight. It's a lot easier to cut off a length of 2 mm brass rod and fit it into a 2 mm hole .

This neodymium magnet which is used to balance the weight of the graphite piston is about 3/4" in diameter and is 3/32" thick. The weight of the whole flywheel is 212 grams. The 4 bolts that run through the aluminum support column and the metal washer are 1 inch long #6 - 32 bolts. The 4 holes that were drilled through the steel washer are 1/8th inch in diameter and are 7/8ths of an inch apart from each other. The outer diameter of the washer is 1 3/4" and the inner diameter is 11/16ths. The outer diameter of the pyrex test tube is 5/8ths of an inch, the inner diameter is 1/2 inch. The height of the test tube is 4 inches. Inside the test tube is Grade #3 Steel Wool. The bulk of the steel wool ends at 3 and 1/4 inches and a couple little strands stick out another half inch.

The piece of brass tubing around the test tube is 21/32 in diameter, it is made by K & S Engineering and can be found at hobby shops or online. This piece of brass is about 5/8ths of an inch long and is located 3/4 of an inch from the end of the test tube. The orange rubber washers which are attached to the pyrex test tube are 1/8 inch thick. The outer diameter of each rubber washer is 1 inch and the inner diameter is 9/16ths. You can find these rubber hose washers at any hardware store such as Home Depot or True Value hardware.

The graphite piston and the cylinder it moves in are part of an Actuator I got from This actuator was about 3 inches long and had a rubber sleeve around it when I first got it. I removed the black rubber sleeve and shortened the glass portion to 1 and a half inches. Check out the pistons and cylinders video I uploaded for more info on that process. The actuator came with a low friction bushing at the end which I replaced with a bearing. This bearing measures 2 by 6 by 2 and a half millimeters. The connecting rod is about 3 inches long and has a ball joint where the connecting rod connects to the graphite piston.

The graphite piston is 1 half inch long and has a diameter of 5/8ths. The metallic end of the actuator came pre threaded with this nut at the end, the inside of the metal end was much smaller and was threaded as well but I widened the inner diameter to 1/4 inch. The actuator fits through a 3/8ths hole in the aluminum support column. The center of this hole is 1 and 3/4ths from the bottom, which is the same height as the center of the hole in the flywheel support column. I added this black rubber O-ring to create an air tight seal between the metal part of the actuator and the aluminum support column.

These 4 holes are 5/32nds in diameter and are 7/8ths apart. These 2 holes here are 1/8 inch in diameter and are about 5/8ths apart. The width of this aluminum support column is 1 and 1/2 inches, the height is 2 and 5/8ths and the thickness is almost 1/8th inch. These aluminum brackets are 1/16th thick and are 3/4 by 1/2 by 1 and 1/2 inch. The holes drilled through the longer side are 1 inch apart and are 1/4 inch in diameter. These quarter inch holes are over sized to allow the brackets and the aluminum support column to be moved a little bit to help center the graphite piston with the crank pin and make it so the graphite piston almost touches the metal portion of the actuator. The bolt running through the bracket and the base of the engine is a 1 inch long #6 - 32 bolt with a washer on each side of the base.

These 2 bolts here are 3/8" long #4-40 bolts. These fit through 2, 1/8th inch holes and secure the aluminum support column to the brackets. Alright, that's it for this video. All the parts used in the lamina 2 engine are pretty much the same as the parts I used in the lamina 1 engine. So check out the lamina 1 plans video if you need any clarification.

To see this engine running at over 1700 rpm check out the Lamina 2 - Lamina Flow Stirling Engine video.