The "Weeble", wobbles into being.

[Captain Jerry]

Tinkering with the engine has paid off. Oiled paper head gaskets made a huge improvement stoping most of the air leak. A packing gland at the crank end of the shaft took care of most of the rest. I am not going to attempt the diagonal seal now, even though I worked out a method to do it without automated equipment. It really doesn't seem necessary. The engine is now running much better. Self starting at all points, regular low RPM at low pressure. I don't have a tach but I can count the revs by eye so I'm estimating less than 100 RPM and all WITHOUT THE FLYWHEEL!

The problem was mechanical. The ball joints where the piston rod connects to the spider must articulate at least 30 degrees. On one cylinder, the one that was stopping at low pressure, I found that at the TDC position the joint was stiff. I disassembled the retainer and added a little more range of motion with a needle file. That's all it took.

I could tinker some more but not for a while. Piston rings would probably be next, but for now, I'm just gonna clean it up and put it on the shelf. I have been hit with the inspiration for a radical new mechanism that needs to be built. It is slightly more complex than the ball pivot used in this engine. I have never seen one, but I can picture it so I'll try to build it.

Jerry

 

[Captain Jerry]

Here is a drawing of the Weeble general geometry. It was produced using an almost free CAD program called CADstd-pro from http://www.apperson.org/cadstd/. I have used this program to import .dfx files from Autocad but have never exported a file to others for import. If you can't read it, you can download the slightly crippled free version or I can post a .pdf file.

If anyone wants more details, I will try to clean up some of the component drawings and put together some build notes.

If the drawings don't come up to standards, I'm not surprised. My only training was with pencils and T-square about fifty years ago in college. Things may have changed a little since then.

Jerry

View attachment Weeble Assembled e.cad

 

[Metal Mickey]

Brings a whole new meaning to weird but wonderful!

 

[artrans]

nice work about that cad program did you use the pro how long did it take you to be able to draw the weeble. Trying to learn some kind of cad but it makes my head hurt. Thank you for your time

 

[Captain Jerry]

nice work about that cad program did you use the pro how long did it take you to be able to draw the  weeble. Trying to learn some kind of cad but it makes my head hurt. Thank you for your time

When I started messing with engines, I did pencil drawings on graph paper.  I thought 3D CAD sounded like fun but gave up on that idea when I realized the learning was keeping from doing anything real.  I tried CADstd free version and almost immediately got usable output.  It has been a while since I started using it but I don't remember it being difficult.  I think the Pro version is worth the investment.

I made the Weeble drawing while building so the time is hard to establish. But it doesn't slow me down. For me, it is way faster than pencil sketchs. I now use it as a thinking tool.



Regards
Jerry

 

[Captain Jerry]

Update:

The CAD drawing posted above is native CADstd format. Here is the .dxf file. Feedback please if you have problems reading this with other CAD programs.

Jerry


View attachment Weeble Assembled e.dxf

 

[GailInNM]

DXF opened fine in ACAD 2000.
Gail in NM,USA

 

[Maryak]

CJ,

No problems with the DXF - Turbocad 14.

Best Regards
Bob

 

[artrans]

jerry i am sorry and do not want to be a pain in the a*** but I will be ;D how did you get the bolts on the plan

 

[artrans]

sorry hit the wrong key i bought the cadsd pro but do not see the bolts like you show on your plans how do you get them thank you
sorry but I have been trying hard to be able to draw a plan like you did and I am hitting a wall. thank you art

 

[Captain Jerry]

i bought the cadsd pro but do not see the bolts like you show on your plans how do you get them thank you
sorry but I have been trying hard to be able to draw a plan like you did and I am hitting a wall. thank you art

Art

No pain at all. CADstd does not have a bolt or screw file to select from. In my plans, I draw them individually. First a rectangle for screw body, then a semicircle for the head unless I intend to use cap screws, in which case its another rectangle. Threads are indicated by a long line and a short line. You do not need to draw long short for the full thread length. Just the first two at the end of the screw. Then use the "Rectangular Array" function. Number of rows = 1, number of columns = how many threads you want. Select the first two thread lines. Start Point- select long line. Second point- select a point where you want the second thread pair to appear.
To be sure that the threads fall where you intend, set "Snap To=Angle". If the drawing is going to have a number of same size screws, draw one in a corner of the page and then copy it to the appropriate position as needed. Use the rotate function to get it vertical, horizontal, or any angle you want. Use Mirror to change left-right, or up-down. If you are going to do a lot of drawings using screws, you can create your own catalog of bolts and screws in a separate file and use "include file" to bring it into your current drawing.

The most helpful hint that I can offer you is to avoid using freehand placement of lines. Get use to using the snap functions.

Hang in there. It should get easier.

Jerry

 

[artrans]

hello Jerry I few more questions I one of those guys That you have to talk real slow to get it.
I am hands on if you were here showing me I would get like now ya right :big: but this way will be my more pain for you sorry. I assume you blew up to larger for ease of viewing when drawing ? And the snap to grit I again assume you have to type in the measurement in x and y or am I missing something as usual. thanks cap

 

[Captain Jerry]

Art

I almost never type in coordinates or dimensions, except when drawing a circle, I do type the radius. Most of my drawings seem to start with a circle anyway.

1. I usually set grid dimension to 1/32 x 1/32 for rough drawings and use fractional inches for dimensions.

2. If you have Snap = Grid, you will not be able to locate a point with the cursor that is not on the grid, so you sometimes have to set Snap=None or Snap=Angle.

3. Locating a starting or ending point accurately is helped by the 8 small locator aids on the toolbar. You can start a line at the intersection of two lines, tangent to two circles,the center of an existing circle, The end of an existing line or the midpoint of an existing line. You can also end a line at any of the references and in addition, you can end a line perpendicular to an existing line or tangent to an existing circle.

4. You can also use these locator aids to set the the start/end points of a dimension takeoff.

Here is an example. The white lines were placed randomly. The red lines were placed using the aids.

Jerry

View attachment Examples.cad

 

[artrans]

hi cap this is the result so far thanks to you I no its not great but it is a start and thanks again for the help still a long road but a least I am moving in the right direction in about 9 years I may be as good as brian. ;D

 

[artrans]

sorry i am a dumb a** did not attach the file sorry

View attachment my_gov[1].pdf

 

[Captain Jerry]

Hey Art

Now you're makin' some lines! What do you think?

I don't want to sound like a teacher or an expert because I'm far from being either but here's a little tip. If you are drawing something like this where the left side and the right side are the same, start with a vertical center line and just draw everything on one side. When you have got it like you want it on one side, use the Mirror X, function to flop a copy over to the other side of the drawing. Half the work and everything is symetrical.

 

[artrans]

thank you for that very good tip which I can use I like it I no I should not be that happy about its not like it nuclear but it is a step in the right direction thank you again for helping out

 

[rleete]

Art, just a pic to show what's possible with a commercial (SolidWorks 2009) CAD program. I rendered this when I loaded the new software, just to see how it worked. Took about 2 minutes for the computer to make it look all shiny. I drew this about 3-4 years ago, when I first got my lathe and was looking for something to make.

There's also a function to animate it (you've seen Brian post it before), which is useful for finding parts that will bind or interfere.

 

[artrans]

very nice I will now go and delete my poor little govener. Ifyou or brian next to me and where willing to teach I would dive into solid works in a heart beat but to try and go it alone
for the cost of the software I would have to be a moran so where do I sign. No realy I would give hugh amounts of something to learn cad again from someone like your self or brian by my side. But until that day comes I will have to stick to my little lines.

 

[rleete]

Not meant to discourage you. Remember, I do this for a living, I'd better be good at it! I went to college to learn it, not just trying to figure it out on my own. Plus, I use one of the most advanced packages there are, with all the bells & whistles, on a top end computer. Most important, I didn't have to pay for it; the company buys everything.

Rather, think of it as a goal to work towards. Like seeing a perfect engine when you are just starting out. Don't let it keep you from your own project, but as something to strive for.