Re: First Engine No Plans.

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wareagle said:
Planetary gearing is a cool thing! I find planets fasinating to watch for some odd reason.

I'm more into stars myself ... :)

Anyway, planetary drives have some interesting features, dependent on what's held stationary, what is driven and where the output is taken. With a sufficiently ... I don't want "complex" but that's the idea ... system of clutches, they can offer several combinations of ratio and direction changes from one set. Well, actually only one direction change unless you count not going anywhere at all as a direction. :D

Sorveltaja, you're right about not seeing any complete sets, though. I think Boston Gear has the ring gears, though, which is a start. After that, it's figure out what will fit for the sun and planetary gears and build to suit. Or do as you did and create your own ring to fit existing gears. This would be an interesting project to watch.

Best regards,

Kludge

 
Looks like super work to me, what was it going to be used for or was it just a "because I can" project (the best kind).

David
 
Outlets are cheap. Put in all you need now and 50% more for the things you will need to do but haven't thought of yet. Put in several circuits while you're at it and you will never regret doing it. Electrical work is really rather simple if done correctly.
 
I have thought of it on a number of occasions, just have had too many other things that were more important. Would work fine for an air engine.
 
When I was 8 years old, in 1955, my family and I took a driving trip from our home in Philadelphia, back to the old home place in a southern West Virginia mining town where they had lived prior to World War Two. As we approached the town, my father, rest his soul, called me to listen very carefully to what he was about to say…

He told me that when we visited the small company-owned house were my grandparents had lived with their four sons, that the next door neighbor would likely come over to see us and if he did, I was not to stare at his left hand, and under no circumstances was I to ask about his hand… no matter what…

When I asked him why, and he told me that the neighbor had cut the top half of his index and middle fingers off of his hand while cutting kindling for the wood stove… the first finger was cut off while holding the target piece of wood because he was distracted by a noise just as the hatchet had fallen. He told me that the news of the tragedy raced through the neighborhoods of the small town very rapidly… my father was at work in the mines when the accident had occurred… Then, as a child would do, I asked how he cut the second finger off…

My father’s reply was that the neighbor had cut off half of the middle finger while showing my father how he had cut off the first one!

As we visited my family’s old friends that day… sure enough, the next door neighbor came over to see us… I can assure you that I could not take my eyes off of his left hand the whole time we were there… but I can also assure you that I NEVER asked him anything about it.

A True Story…
 
You will know when you are finally mastering the machinists arts when you learn how to cover you "mistakes".

Or better yet, It wasn't a mistake, you just re-engineered it on the fly...
 
Hey - that's a splendid contribution. I looked at the Elmers Beam and dismissed it as having too many tiny fiddly bits. At this scale, they get less ANNOYING.

However, now you've made it bigger I am tempted to put in some embellishments just to make it harder again. e.g. make the beam and cylinder more authentic.

Brian - did you post the CAD files anywhere? (I'm a 2D cad person right now). If I create anything useful as a derivative then I would, of course, repost.

Cheers, Adam
 

A novice novice's thoughts on the original question, "Why does the engine jump?".

In the video the camera is moving around so much it's hard for me to tell in just what manner it is jumping (but I really liked the view of the governor in action).

If the engine was trying to slide horizontally on the table then I might think it was due to the rocket effect caused by the piston moving and the cylinder head not. The old for-every-action-there-is-an-opposite-and-equal-reaction thing.

But if one end of the engine tends to lift (which is what I think is happening) then it is a result of the torque generated on the crankshaft. When the engine fires the connecting rod pushes against the crank which tries to turn the flywheels faster but due to inertia the flywheels resist this change in motion resulting in an opposite force back on the rod. This opposite force then acts to rotate the whole engine causing the jump. Same as when a heavily loaded semi truck starts to pull away and you see the whole tractor cab lean over to the side.

In either case it sounds like you had a pretty powerful engine. Your choice of reducing the compression ratio was one way to solve the problem, but if the jump was due to torque wouldn't lightening the flywheels have also helped? Maybe even taking one of them off? Of course that would have resulted in a higher revving engine which you may not want. Oh, and wouldn't decreasing the fuel have helped as well?

Anyway, those are my never-been-there, never-done-that thoughts. Anybody is welcome to correct me if I'm wrong.

 
My first crack at turning eccentric pieces and I'm pleased, but darn it if these little parts are not rough on the eyes.

PB040049.jpg


Jim
 
Another trick that delivers a smoother finish on wood turnings is to use the normal sanding procedure down to the fine sandpaper, but then run the lathe in reverse - helps to take all the little fuzzies off that all lay down the same direction and bends them over the opposite direction and give a much smoother finish when varnished, oiled or whatever.
 
You might look for the GEARS program - its a DOS based program, takes your parameters and outputs a dxf file of the gear. There are several places you can download it.
 
A methanol based fuel is also nice from a safety point of view as compared to gasoline. Lower vapor pressure, less volitile, doesn't burn quite as redily, and burns a lot less explosively. Makes it safer to store in places you would never store gasoline. Methanol can also help with cooling and engine - Knew a guy that ran a sprint car on methanol and would actually have frost on the manifold before the engine got warmed up.

You do need to be somewhat careful about compression ratios. if you get to high a compression ratio with a glow engine you will get detonation or pre-ignition and it will generate a lot more heat and also be rather hard on the mechanical components.
 
This link will be a good source for toy steam engines from around the world. http://www.toysteambible.org/ it is a work in progress but is a great site for more eye candy or what is it I just bought!
glen
 
You might try looking into one of the variable belt speed controls like used in lawnmowers today. They have a double groove pulley - BUT - the center piece of teh pulley floats side to side - there are 2 belts - one from the drive pulley and one to the driven - as you shift the pulley back and forth the ratio changes and thus the oputput speed changes. Lawn mowers have used teh idea for years as it is cheaper than a hydrostatic drive but gives a good range of speeds.
 
I programmed the VFD this morning, then hit the run button. Mill motor runs and spindle turns in the correct direction, both fwd and rev. So far only "issue" is a bit of a rattle in the pulleys. I called the prev. owner this morning, and he says it was like that, so we'll see what happens when I try to make some chips later on.
 
I've bought O1 silver steel/drill rod from Bohler-Uddeholm in Brisbane. I think they only usually carry the oil hardening variety.
 
...I just checked the Loctite website www.loctite.com and looked up information on retaining compounds (609, etc.) I was surprised to see that Loctite DOES recommend them (some of them, anyway) for press fits. That contradicts what I'd seen previously, and "common sense," but they ought to know. (Or they're' trying to sell Loctite. ;D ) For details, check the website.
 
What is the parking like at the show? How much does it cost? Never been there before so I was just wonderring how it is to get in and out.
 
If you are displaying here are a few hints.
Water /beverage/snack it is hard to get away from the table to eat.
the show supplies 1/4 npt taps to the air lines
bring air regulators with separator(One year we drained a half a pint of compressor oil from the line my son was hooked to.) fittings, teflon tape barb fittings aquarium valves aquarium tubing. Barb fittings etc (this is the stuff I use)
Tools to fix engines and assemble disassemble air lines.
lock tite has saved me more than once.
Scissors, markers, pens, note paper, business /contact cards if you have them
I bring cloth table covers to dress up the table and my display is elevated. Also a cover to cover the display before the show starts or at the end of the day. The venue has plenty of metal chairs but a chair pad or camp chair can help the sitter.
Tin
 
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