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Off topic => Break Room => Topic started by: bruski on August 08, 2018, 02:35:39 PM

Title: Another hobby
Post by: bruski on August 08, 2018, 02:35:39 PM

Here are a few pictures of the Demon V-8 that I have been working on here and there. It has a 5/8\" bore and a 5/8\" stroke. Most of the block and head machining I did with my Robotool cnc mill when it was still working. The cam was ground with a camshaft grinder that I made, and the crank was machined on my lathe. 


bruski


Title: Another hobby
Post by: Cutter on August 08, 2018, 02:56:48 PM

BITCHIN !!


Title: Another hobby
Post by: Sparky_NY on August 08, 2018, 03:07:41 PM

Fantastic Bruski !     


Title: Another hobby
Post by: Roller on August 08, 2018, 06:37:44 PM

Very impressive!  Nice work!


Title: Another hobby
Post by: Dave on August 08, 2018, 10:12:16 PM


BITCHIN !!




I like Bitchin! Lmao


 


Keep us updated with progress! PLEASE!!!!


Title: Another hobby
Post by: bruski on August 21, 2018, 07:50:11 PM

Here are some machining pictures of a scaled up version V-8 with a 1 inch bore and 7/8\" stroke.


bruski


Title: Another hobby
Post by: Sparky_NY on August 21, 2018, 09:24:39 PM

You building that V8 too Bruski?


Title: Another hobby
Post by: bruski on August 21, 2018, 10:30:07 PM

Sparky,


 Yes, I like to jump around a bit on projects. Those machining pictures are from a few months ago while my Robotool cnc mill was still working. Right now I am trying to come up with a simple good functioning magazine for the 357, but I am drawing a blank.


bruski


Title: Another hobby
Post by: Sparky_NY on August 22, 2018, 06:54:09 AM

I am a big fan of miniature engines.   Maybe some day.


Title: Another hobby
Post by: bruski on August 22, 2018, 12:58:27 PM

They are a lot of fun to build and hear them run in the end. I have built 6 or 7 gas engines a couple of hot air engines 2 gas turbine engines plus about 6 pulse jet engines and a few steam engines in the past. Any time I come across something interesting, I will probably build it sooner or later. I built a go kart with two 60 pound thrust pulse jet engines on it that I still have so I can get the Adrenalin going again. I don\'t know the top speed of it yet as I still ride the brakes on that one getting those oh sh#t feelings constantly one after another.


bruski


Title: Another hobby
Post by: bruski on September 08, 2018, 01:46:51 AM

Here are a few more pictures of my scaled up Demon V-8 engine. The blower is a sliding vane type of air pump which is more efficient than running two rotors that are double lobed. It looks like it has two rotors by the looks of the bearing caps. I temporarily am using glow plugs in the heads but it will run with a spark ignition after break in. The two gears on the output shaft are temporary for an extra heavy flywheel. The engine has split shell bearings on the crankshaft mains and rods. It is still too tight to run by itself yet and needs some run time in the lathe about 2000 rpm which is still below the idle speed.


 


bruski 


Title: Another hobby
Post by: maccrazy2 on September 08, 2018, 09:24:03 PM
Looks like there is spot holes for a water pump.
Title: Another hobby
Post by: bruski on September 09, 2018, 07:47:54 PM

Mccrazy2,


 There are spot holes that need to break through to the water jacket but maybe at a later time. I run these small engines on 20 % nitro model airplane fuel and the alcohol evaporation does a good job of cooling short runs.


 


bruski


Title: Another hobby
Post by: maccrazy2 on September 10, 2018, 09:34:22 AM
Very cool
Title: Another hobby
Post by: maccrazy2 on September 16, 2018, 10:13:06 PM
Does this engine use piston rings?
Title: Another hobby
Post by: bruski on September 17, 2018, 12:30:00 PM

Mccrazy,


 They do have two rings one chromemoly top ring and a cast iron ring below it. I turn these from solid bar stock a little less than .001 oversize of the bore. As you can imagine, the smallest of a burr on a ring can increase break in time by a factor of 10 times longer than a perfect ring. There is not much outward spring pressure on the cylinder walls from these tiny rings. I don\'t use any oil control rings so there is a little bit of oil pumping past the rings while breaking in.


bruski