New here;seeking answers to "project impossible?"

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j_polacchi1

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I have a great interest in a project that I am desperately in need of advice and assistance.I have a small machine shop I am slowly getting together,a small1950-55 Logan lathe and a Hardinge TM-UM mill w/a Bridegport M head.I hope to be up and running inside of the upcoming year.I'm well versed in most machine tool set ups and operations,but I'm not much of an engineer I'm afraid.I've never made a working engine from scratch and it seems to be quite an undertaking.

I was wondering if anyone has made a V-Twin design diesel engine?I see/find plans and of gas engines or very small "model plane" types w/glow plugs,but no true diesels to my knowledge.I'm aware of the subtle differences in diesel engines,but really only the basics.The 20:1 compression ratio is pretty important,the bore/stroke might also be a key factor?Fuel delivery considerations (should it be carburator or fuel injection type?), and whether or not a radiator/water cooling would be necessary (which I suspect it probably will be).

I'd like to make an engine large/powerful enough to power a bicycle w/an average person on it.Maybe I'm aiming a little too high or possibly tackling something that can't be done(I'm not sure?).I just can't find prints or answers to design/manufacturing questions and require the assistance of those who are more "well versed" on this subject which is why I decided to join this website.I would be grateful to receive any helpful assistance,advice or suggestions in this endeavor to get started.
 
Some examples of true model diesel engines in a single cylinder configuration have been built.

[ame]http://www.youtube.com/watch?v=gvSAnpn_YHw[/ame]

[ame]http://www.youtube.com/watch?v=zXzqGHn0CDY[/ame]

They require quite a bit of machining skill to complete. I'm not aware of a carburator fueled diesel engine.

From my own experience as well as that of many members here, building engines that run well is a progression of learning experiences that begin by making simple air operated engines, to more complex air or steam operated engines. Some may go on to building an IC engine which may introduce a whole new set of machining practices.

Since you've never built an engine we can't determine where your skills reside. Only you can determine if your skills are up to it.

Cheers,
Phil
 
Diesel with carburetors are common in model airplanes. These use fuel containing ether, kerosene, and lube oil. Injected engines have been built, but there are only a handful that run well. The red one above is very good but the builder doesn't talk about his injection pump design. The second doesn't run very well at all in my opinion, and its been said the fuel contains ether as well. The power output and longevity under load of these engines is unknown. Injection components at this scale are very small. The smallest commercially produced injected diesels are about 3HP (160CC) or so.

If you haven't found the Lohmann diesel bicycle it's worth a look.
 
Hmmm...I seem to be having problems with the web page,so I'll try this.Well,in answer to the above question(s),admittedly my machinist skills are "average" at best.I know most all the basics and anything I don't know I refer to "my book" or to the good 'ol machinist bible (the machinery's handbook).Of course I am limited by tooling (what tooling I will have at my disposal).I don't think my Hardinge is coming with a rotary table,just some 5c collets and a mill vice(what kind I don't know?),so no real way to produce nice arcs or radius's. I had been able to set up and program CNC machines,but it has been a long time since I have done that.I have forgotten most of my "G" and "M" codes.I'm sure I can get my CNC skills back in a short period of time.Perhaps in the future I might invest in a small table top CNC machining center,maybe Dyna or something?I'm not convinced of any of Sherline's table top mills CNC or conventional.They look too flimbsy to me and at best can realy only produce "very small parts".I know it takes allot of parts to make a working engine be it a diesel or gas running motor.There are blueprints and kits out there for gas engines I have seen/found.I have often wondered if a crank and cam from the gas engine kits can be used to make a diesel motor out of it?Maybe utilize the piston rods and valves/valve springs...small parts like that?The problem I can see is designing the engine block,cylinder heads and pistons to generate and can take that 20:1 ratio and probably the heat generated by a diesel.Trying to modify a gas burning motor into a diesel I have heard/read can/will produce devastating results.I don't know what the "stroke" should be or if that is an issue that requires attention?The problem for me(for the most part) isn't making the parts so much,but the grand design itself.I've had this idea for quite a while,to make a small diesel engine for a bicycle type frame and preferably to either have it runoff of diesel itself,biodiesel or perhaps even "peanut oil",which I believe(if I am not mistaken?) is what the original diesel engine ran off of,and why not?
 
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