Johnsinski
Member
- Joined
- Nov 4, 2011
- Messages
- 6
- Reaction score
- 2
Hello all, I ran across this forum looking for something else. But I figured you guys would appreciate my project from the "before" time, before 3D that is. I started this around 1995ish and finished it in 1997ish (sometime before graduation). Back then 3D was just coming around. Pretty much all of this was done with hand programmed "parametrics" and designed in 2D. Alot of Quickbasic programming to produce 3D G-code.
This is actually my "second" engine, the first one was a little single, to my amazement it actually ran and flew a model airplane so I decided the next step was a 100cc V4.
When I told the guys at Sundstrand that I machined the pipes to .050" thick from billet they looked at me funny.
I machined the "reed" valves from nylon or delrin or something "double-stick-taped" to the CNC table. (I got more odd looks with that maneuver too).
I also detected a "metric" Z ball lead screw in one of the CNCs during this project because of all the weird set-ups. I was getting a TLO error that just wasn't explainable.
The crank is 17 parts pressed together, with needle bearings on each rod. Each rod is "clocked" 90 degrees which fires the two inside cylinders at the same time and then fires the two outside cylinders at 180 degrees from that. It seemed like a reasonable thing to do. There are delrin seals between each double bearing to seal each crankcase volume from the next.
The cylinders have "port-cores" in them for smoother flow (unlike the standard glow engines). You can just barely see them.
When I tell people I designed and built this engine, they usually say, "that's nice". And then I have to explain, "no, I mean, I designed and BUILT this engine, from like chunks of aluminum and steel." Some people still don't get it. I like to say I built everything but the bolts and bearings.
I never really got it to run all that great, the 90cc chainsaw carb just couldn't flow enough methanol. I figured it was good enough and moved on to something else.
[ame]http://www.youtube.com/watch?v=X0kVLtxvKwU[/ame]
This is actually my "second" engine, the first one was a little single, to my amazement it actually ran and flew a model airplane so I decided the next step was a 100cc V4.
When I told the guys at Sundstrand that I machined the pipes to .050" thick from billet they looked at me funny.
I machined the "reed" valves from nylon or delrin or something "double-stick-taped" to the CNC table. (I got more odd looks with that maneuver too).
I also detected a "metric" Z ball lead screw in one of the CNCs during this project because of all the weird set-ups. I was getting a TLO error that just wasn't explainable.
The crank is 17 parts pressed together, with needle bearings on each rod. Each rod is "clocked" 90 degrees which fires the two inside cylinders at the same time and then fires the two outside cylinders at 180 degrees from that. It seemed like a reasonable thing to do. There are delrin seals between each double bearing to seal each crankcase volume from the next.
The cylinders have "port-cores" in them for smoother flow (unlike the standard glow engines). You can just barely see them.
When I tell people I designed and built this engine, they usually say, "that's nice". And then I have to explain, "no, I mean, I designed and BUILT this engine, from like chunks of aluminum and steel." Some people still don't get it. I like to say I built everything but the bolts and bearings.
I never really got it to run all that great, the 90cc chainsaw carb just couldn't flow enough methanol. I figured it was good enough and moved on to something else.
[ame]http://www.youtube.com/watch?v=X0kVLtxvKwU[/ame]
Nice engine.
