SpudFiles

The general concept garnered some interest elsewhere, and it's a relatively simple machining project if you're so inclined. It's been on my to-do list for years now. The plans are generally a pain in the ass to find, with people trying to make it payware, but I have a copy, so I thought I'd share. Horton's plans date back to the late '60s or early '70s, there was I believe a Popular Mechanics (or similar publication) article on an earlier engine of his running on acetylene in the late 60s but I've been unable to find it. Akin's 1974 thesis is based around a similar but larger design using VW "beetle" cylinders. I'm unable to attach the PDFs here, so I've shoved them on my dropbox, links below.

Free piston engines are pretty good compressors, the earliest reference I've found was a 1912 article in Popular Mechanics for a free piston compressor (linked below), and the Germans used a Junkers-developed free piston engine in WW2 as a compressed air source for torpedos.

enjoy, or don't.

1912 PM article - https://books.google.fr/books?id=A94DAA ... on&f=false
A review of free piston engine usage - https://www.mikalsen.eu/papers/FPEreview.pdf

Horton's "Loudmouth" plans : https://www.dropbox.com/s/1d3hqhyztwn9c ... s.PDF?dl=0
Horton's "Loudmouth" instructions : https://www.dropbox.com/s/sp16o3anzhaqe ... 5.PDF?dl=0
Akin's 1974 MIT thesis : https://www.dropbox.com/s/w585xfxb47dzz ... y.pdf?dl=0

mrfoo wrote:The general concept garnered some interest elsewhere, and it's a relatively simple machining project if you're so inclined. It's been on my to-do list for years now. The plans are generally a pain in the ass to find, with people trying to make it payware, but I have a copy, so I thought I'd share. Horton's plans date back to the late '60s or early '70s, there was I believe a Popular Mechanics (or similar publication) article on an earlier engine of his running on acetylene in the late 60s but I've been unable to find it. Akin's 1974 thesis is based around a similar but larger design using VW "beetle" cylinders. I'm unable to attach the PDFs here, so I've shoved them on my dropbox, links below.

Free piston engines are pretty good compressors, the earliest reference I've found was a 1912 article in Popular Mechanics for a free piston compressor (linked below), and the Germans used a Junkers-developed free piston engine in WW2 as a compressed air source for torpedos.

enjoy, or don't.

1912 PM article - https://books.google.fr/books?id=A94DAA ... on&f=false
A review of free piston engine usage - https://www.mikalsen.eu/papers/FPEreview.pdf

Horton's "Loudmouth" plans : https://www.dropbox.com/s/1d3hqhyztwn9c ... s.PDF?dl=0
Horton's "Loudmouth" instructions : https://www.dropbox.com/s/sp16o3anzhaqe ... 5.PDF?dl=0
Akin's 1974 MIT thesis : https://www.dropbox.com/s/w585xfxb47dzz ... y.pdf?dl=0

Very interesting. Seeing the material.