Redo of Elmer's Standby for beginners

[black85vette]

Here are some more drawings.   They are in .pdf and easier to zoom in and read them.   I put the second and third valve configurations together on a page.

[black85vette]

Here is the 3rd valve type for this engine build.   Same valve configuration as my original EZ Engine.   Quick and easy to make and runs great.



IMG_5920 by black85vette, on Flickr



Quick shot of it running on about 5 lbs.   It will run well under 2.


<a href="https://www.youtube.com/watch?v=GkaXeh-p2p0" target="_blank">http://www.youtube.com/watch?v=GkaXeh-p2p0</a>

[Alan Haisley]

Rick,
Do you think this is too short coupled to include a double acting cylinder? Maybe remake the base to extend the coupling and then add a whole bunch of double acting valves too.
Alan

[black85vette]

Rick,
Do you think this is too short coupled to include a double acting cylinder? Maybe remake the base to extend the coupling and then add a whole bunch of double acting valves too.
Alan

Alan;

Certainly a piston valve could be used for a double acting cylinder.   It adds some complexity.   The piston would need a connecting rod running through a gland of some sort.   Don't know that this design could be modified to do that.   It does present a great design challenge.  Can we design a beginner double acting engine?  Maybe an intermediate design?

How would you go about the cylinder head / connecting rod?


Edit;  Just went and looked at some files I have collected and another of Elmer's looks promising.   The Slider is a basic double acting engine that is not too complicated.

[Alan Haisley]

Rick,
Looking at your design got me thinking about a progressive engine: one that starts out simply and switches in more difficult or complicated pieces as the hobbiest develops skills.
To go from where it is to a double-acting engine it would need a gland plate as well as a guide. The two together would hold the packing in place. Maybe make the gland as a flat plate and flange the guide, then bolt through both of them. Then single acting with an articulated connecting rod would just omit the gland. Gives still another mode to assemble it in.
By using the separate valve block like you do, the engine avoids the problems a beginner can have when a part needs a lot of machining steps before it's done. No drill, bore, face, drill steam ports, drill bolt circle, on and on, and one mistake loses it all. If you want a perfect beginner engine I think this is it.
Alan

[black85vette]

Rick,
Looking at your design got me thinking about a progressive engine: one that starts out simply and switches in more difficult or complicated pieces as the hobbiest develops skills.
To go from where it is to a double-acting engine it would need a gland plate as well as a guide. The two together would hold the packing in place. Maybe make the gland as a flat plate and flange the guide, then bolt through both of them. Then single acting with an articulated connecting rod would just omit the gland. Gives still another mode to assemble it in.
By using the separate valve block like you do, the engine avoids the problems a beginner can have when a part needs a lot of machining steps before it's done. No drill, bore, face, drill steam ports, drill bolt circle, on and on, and one mistake loses it all. If you want a perfect beginner engine I think this is it.
Alan

I was thinking about this today and realized that the 3rd valve (barbell piston) would just need a second port on the side to make it workable as a double acting valve.  Cylinder just needs an additional port at the open end.  I could shorten the piston just a bit to make some room.  I think your idea of a plate as the gland would be workable.   Just need to workout a simple crosshead.

This could be fun.  Thanks for the ideas.

What next?   flyball governor?   Hit/miss version?   


Edit;  just looked at the layout and I think there might be room to do this without moving anything.

[black85vette]

How about something like this.   Ream it at .125" for the connecting rod and packing may not be necessary.   At .375" it could be long enough to not need a cross head / guide.   Just bolt it up to the face of the cylinder block.   I added the second port for the cylinder and valve.   Have not tested this idea.   It is just on paper.

[zeeprogrammer]

What next?   flyball governor?   Hit/miss version?   

A hit/miss! It's a popular engine and no doubt a lot of newbies are interested in it. Me for one.

[zeeprogrammer]

I was doing a little searching on twin cylinder marine engines (that's right - I haven't made up my mind)...

Came across John's Paddleduck which led me to www.machinistblog.com where John's plans are available.

The site also has your EZ Build Engine.

Also on that site is hit-n-miss engine made from barstock material and a link to get free plans.

[black85vette]

I was doing a little searching on twin cylinder marine engines (that's right - I haven't made up my mind)...

Came across John's Paddleduck which led me to www.machinistblog.com where John's plans are available.

The site also has your EZ Build Engine.

Also on that site is hit-n-miss engine made from barstock material and a link to get free plans.

I had been to that site some time ago but forgot that they had posted the EZ Engine.   They have plans for a combination tool for a mill that looks like something I need to make.

[black85vette]

Without the friendly prodding by Alan I might not have gone this next step.   Here is the double acting version of this little engine.  This will take a little more skill since the pistion rod / head / gland all  need to line up and have minimal friction from alignment issues.

Here is the piston.   .375" long x .5" diameter drilled through the center with a .125" hole.   The .125" stainless shaft then attaches to the end that I made of brass to connect to the linkage going to the crank pin.


IMG_5926 by black85vette, on Flickr


The combination head / gland is .375" thick.   The .125" hole for the piston rod needs to be drilled under size and then reamed to .125" and its placement in the center of the head and .375" down from the top is pretty critical.   This must be centered on the cylinder and parallel to it for the piston to travel without interference.   Then I drilled a hole half way through to connect to an air passage for this end of the cylinder.   Two more holes are drilled and tapped to bolt the head to the cylinder body.   I used 10-32 but other sizes would work.



IMG_5927 by black85vette, on Flickr



IMG_5928 by black85vette, on Flickr


A hole is drilled in the valve body to provide air to the second end of the cylinder.



IMG_5929 by black85vette, on Flickr


Here is the new head and cylinder body;



IMG_5930 by black85vette, on Flickr


These are the new parts;


IMG_5931 by black85vette, on Flickr


I will upload the video in just a few minutes.

[black85vette]

Here it is running.   Nice thing about double acting engines is how slow you can get them to run if everything is fit well.

<a href="https://www.youtube.com/watch?v=tRTpRsP7RNI" target="_blank">http://www.youtube.com/watch?v=tRTpRsP7RNI</a>

So there is a beginner engine with 4 valve configurations and using common components to reduce materials and most of it made from the .75" x 2" aluminum bar.   A mill is not mandatory but really nice when doing two flat mating surfaces like the head / cylinder.  However some sealant or gasket would do as well.

[Alan Haisley]

Rick,
One thing I found hard to do with my first tries at engines was to bore a flat-bottomed hole. Why not take the simplification one step further: Make the cylinder a through bore and put a plate on the right end like the new one for the left end (only without a hole for the piston rod of course.)
Alan 

[black85vette]

Rick,
One thing I found hard to do with my first tries at engines was to bore a flat-bottomed hole. Why not take the simplification one step further: Make the cylinder a through bore and put a plate on the right end like the new one for the left end (only without a hole for the piston rod of course.)
Alan 

You have excellent ideas!       I could do that and put the rear air connection on it as well.    Then the McCabe runner valve could also be just a bolt on to the rear of the engine.

Keep the ideas coming.

[black85vette]

Another update and modification.   I liked the idea of boring through the cylinder.  Adding a piece to the rear gives some additional flexibility as well.   In the picture is the standard rear piece where I have moved the air connection.   You can use this for most of the engine configurations.    Then I made a rear piece to house the piston valve with the hole in the middle.    The same piston can be used in its own standalone valve body or in this one attached to the rear of the cylinder.  You just make the one piston for both uses.



IMG_5939 by black85vette, on Flickr


So there are now 5 possible configurations;

1. rotary valve
2. piston valve with hole in valve body
3. barbell piston valve in single acting
4. barbell piston valve in double acting
5. piston valve with hole mounted to rear of cylinder with a bell crank

Thinking about calling this the Modular Engine Sub-assembly System.   Or;  MESS for short.   Name of the build post should be "How to make a Mess".