A Rocker - My Very First Build

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George_Race

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I have been lurking around here for some time now and I finally decided to do my very first engine build. I was greatly encouraged by attending the N.A.M.E.S. show near Detroit last month. Meeting Steve, George, and many other HMEM members really encouraged me to get started on my first build.
I decided to build a simple Rocker and downloaded the prints from a HMEM post. After about 15 hours of shop time I have a RUNNING ROCKER! How exciting to see my very first engine come to life!
I started with a block of brass for the cylinder. Trued it up with my home brew mill. Then using CamBam, I drew the cylinder end cutout and the cylinder bore and produced the G-Code for Mach3. Doing that successfully, I then repeated the process for the flywheel. Both really came out great, for my very first try!
Here is a pictures of the finished Rocker:
Wobbler.jpg


The picture below shows the parts that I built. As I did a few things differently then shown in the print, I though I would give you a blow by blow description of what I did a bit differently along the way.
At the left you see the finished cylinder block. I press fitted the shaft bearing in place. The base is at the top, the flywheel at the bottom. I decided to tap the flywheel mounting hole to 6-32 and thread the drive shaft. When doing the final assembly I will use a dab of Loctite to hold it in place. On the right of the picture, the first item is the air line adapter. It is threaded 10-32 as shown in the print and I machined a hose barb on the end of it. Below that is the piston and to the right of it the cam assembly. I drilled the connecting rod end of the piston to clear a 2-56 screw. I then drilled and threaded the cam rod hole 2-56. I also threaded the cam mounting hole to 2-56 as well. The last piece is the drive shaft. I threaded the flywheel end 6-32 and tapped the other end 2-56 to screw the cam to. When assembled, it really makes a nice assembly. In final assemble all the threads will have Loctite to hold the screws in place.
So there it is, my very first build, AND IT RUNS! Wow, I am so pleased!
Wobbler Parts.jpg
 
Hi Marv:
Not sure what you mean, they are showing on my page.
George
 
Congratulations!!!
Your first runner!!! ;D

My first attempt at this simple engine did not run....
I am going to be trying again and using some new knowledge i hope i can do better!

Looks nice all done up in brass!

Andrew
 
I see them now but they weren't there earlier when I read the post. Must be some delay at the place where you hosted them.

Regardless, you've done a very nice job. Savor the thrill. First run for any engine is always an exciting moment but first run of first engine is the best. I still remember mine and it was many years ago.
 
Marve, I think I was probably uploading them as you read my post. I sent the post and then want and uploaded the pictures to my site.

Yes, I am really encouraged to build something else soon. Having my first build run the first time is really great. I guess it goes to the original design and making sure the tolerances are all where they belong. I wish I had started this as a hobby many years ago. I am gong to have a lot of fun making scrap out of good pieces of metal!
 
It looks like the piston tilts in the bore, George, is it hemi-spherical? Lovely shade of brass too!
Stew
 
Hi Stew, no it is not a hemispheric cylinder, it is a straight .375 bore with a flat bottom. The piston is only .020 thick and the same size as the cylinder, just polished on the edge enough to make it not bind in the cylinder.

When I first saw this design I did not think it could ever run, but it does, and really very nicely. It has no valves but simply vents as the piston tilts in the cylinder.

It is called a "Rocking Steam Engine" If you search this forum you an find and download the print set. I would attach a copy but it is just over 700K in size which is larger than allowed here.

The brass looks better in the pictures than it does in person. My picture taking lighting kind of warmed up the look. In reality it is a bit more brassy in look, but does look very nice.
 
Congratulations George. Like Marv said - the first one is memorable. Nice job on the engine and keep us posted on your next project.

Cheers,
Phil
 
Very nice engine. Congratulations. Now lets talk terminology. The engine you have built is indeed a 'rocking' engine but is not a "wobbler". A "wobbler" or "oscillating" engine is one on which the cylinder itself 'wobbles" back and forth on a pivot to open and close valve ports. You have done a great job, and it is a thrill when your first engine runs. ----Brian
 
Very well done George :bow:

;D ;D I happen to share your pleasure; my first runner was this very same rocking engine design nearly 2 years ago - brings back a flood of memories ;D ;D - that feeling of getting a first runner is the best ;D - and each engine after that is just as much fun!

Kind regards, Arnold

 
Very nice George, A job well done on a first build, Dave
 
Brian, thanks for setting me straight on the type of engine I built. I have taken the liberty of changing my post to reflect the correct name. Thanks again for the correction.
 
Nice engine. Never seen that design before--a rocker. I too would've been leary of it working. Another for the to-do list. Thanks for sharing.
 
Nice Rocker George :bow: :bow:

Best Regards
Bob
 
Thanks to all for the very kind words about my very first build. I look forward to doing another project soon, and in fact, have chosen to build a Stirling Cycle type. I will attempt to take pictures along the way and share how I am doing it.

I really got very lucky, with my limited machining skill set, having the Rocker run as my very first build. I don't think I will be that fortunate in the future. I must say that without being here on HMEM, reading all the posts, and even getting answers to some of my questions has played a big part in my early success with the Rocker build.

Thanks a bunch to all for letting a newbie step in and run with the "Big Dogs," while observing and learning a lot from all the skill displayed on this forum.

George
 
Congrats on a very nice first engine!!!
You mentioned using a home brewed mill, would like to hear more about that, it seems to work quite well
 
Yes, I did put together my own mill. I started with a K2CNC 2414 platform. I built up the electronics from Hobby CNC and use a Bosch Router as the spindle. For design software I use AutoCAD, CamBam, and Mach3 to do all the work. I have a rotary 3 jaw chuck that I bolt on to the table when necessary. I have three different size collet sets that I use in the Bosch to hold the tools. Along the way I have learned to use edge finders, calipers, and read a lot of charts and things on the web. I also have a HF 7X10 Lathe that really works very nicely. I am a beginner machinist and putting together little hobby shop has been a lot of fun. I can see where building model engines is really a lot of fun and challenging. I need things to do to keep me busy during my retirement years.

Here is a link to some mods I did to my lathe:
http://www.mrrace.com/Mini_Lathe_DROs/

Here is a link to a Mach3 screen that I wrote, along with a picture of the mill.
http://www.mrrace.com/SimpleMill/

I also have a group of "Single Line" engraving TTF Fonts that I put together for engraving materials using CamBam. They are True Type Fonts and will work with other programs as well. They can be downloaded here:
http://www.mrrace.com/CamBam_Fonts/

I have spent my working life working with Computer Programming and the Web, working as a Plant Supervisor. I have always enjoyed working with my hands and repairing and building stuff. From building my own home, to building any flying my own airplane, I have had a lot of fun along the way.

Hope I have not bored the group with all the details,
George


 
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