Building a double acting wobbler

[Brian Rupnow]

I have decided that since I had such good luck building a basic wobbler steam engine (One of Elmers Engines), that I would try something similar but a bit larger. I am going to build a double acting wobbler based on plans posted by Eric-Jan Stroetinga of the Netherlands. This is a nice looking engine, the only thing that concerns me a bit is that the cylinder caps are glued in place with loctite 648. Has anyone built this engine or do you have experience with loctite 648??? I plan on building Chucks poppet valve horizontal engine, but want to improve my skills a bit more before tackling it.---Brian

View attachment WobblerEJS.pdf

 

[nemt]

Hallo Brian,
I think there is no problem in using the mentioned Locktite. In general the temperature of these engines running on steam is around 100 deg. Celsius.
No problem for the locktite.
On you site I saw that you use Solid Works or drawing! I teach students to use SW in our college and like to use it myself.
But sometimes I still use Acad for 2D drawings.
Nemt

 

[lugnut]

That engine your showing is the first one that I made.. It runs great I used the locktite and it work very well.. I'm glad you posted the plans as I lost mine and couldn't remember where I got them.
Mel

 

[Brian Rupnow]

Progress is being made. I finished the crankshaft and the crank "throw", but I have to go to town today and buy some material. My new milling machine is supposed to be delivered on the 26-June, and some of the parts for this engine will be built on it. I have never used a milling machine before, so I am going to jump in with both feet and make chips.

 

[bretk]

Brian,

Nice progress 8) As for the mill, there is nothing quite like jumping in with both feet ;D

-Bret

 

[Bogstandard]

Brian,

Jumping in with both feet with any machinery can be a very dangerous and expensive exercise, and the milling machine is no exception.

I would suggest you just dip your toes in first, and spend as much time as possible before the machine arrives, on reading up and inwardly digesting the various safety precautions about using a mill.

You will not be able to get anyone here to give you all the information required to operate a mill with reasonable safety and accuracy, because to do it correctly can take many years.

I would suggest as a minimum starting point look for articles on

Climb milling - a very dangerous exercise if you don't know what you are doing. This is the cause of more milling accidents than anything else, and a certainty to be done by a beginner who has never milled before.

Milling cutter types - you need to know the basics of the operation of three basic cutters that are in general use by beginners, slot drill, end mill and fly cutter. All have their own specific uses, and all can be used to do the same sorts of jobs, within the limitations of the cutter.

Setting up and workholding in a vice - it is no use just holding the piece part in the vice and hoping for the best. The vice has to be set up correctly in relationship to the table and cutter, and the job has to be held correctly and safely in the vice jaws in the right position.

If you can read about and understand the three items above, you stand a chance of staying almost safe, if you can just remember to take very small cuts on your initial experiments. Always play safe.

There is a another set of rules, but I would expect you to be using them already, the usual things, safety glasses, no loose clothing etc. You can replace cutters and lumps of metal, but not body parts (well you can, but not very efficiently).

I am sorry about going on about this matter, and not being able to supply the relevent information, but you will soon be starting on another journey, and need to get the correct ticket to get to your destination.

Best of luck on your trip

John

 

[Brian Rupnow]

John---I appreciate your concern. Believe me, I know the danger associated with powered machine tools. In my years as an apprentice during the 1960's I seen a senior engineer killed instantly in the shop. He had come across from the office to see how a large lathe job was progressing. He leaned in for a close look while the machine was running, and his neck tie got caught up in the revolving part and broke his neck!!! I have been operating power machinery for over 40 years--I build custom racing cars and hotrods as a hobby. I have been reading books on mill operation, and downloading a number of articles from the internet and studying them as well (There are a number of very good articles on Little Machine Shop and places like that.)---When I said that I planned on "jumping into" my project, I plan on wearing my "safety parachute".

 

[Bogstandard]

Brian,

Sorry about that, I thought you were new to the game, and as you know, it's always better to be safe than sorry.

At least if a newbie reads it, it will give them a pointer in the right direction. So it won't be wasted.

John

 

[bretk]

John,

If you get a chance, check out Brian's website. He has done some interesting stuff in his career 8)

-Bret

 

[Bogstandard]

Bret,
I now remember going to Brian's site and giving it a dose of looking at. Many years ago, they were the sort of machines I specialised in repairing, one offs, for doing a specific job.

But as usual my brain cell let me down, and I had forgotten. I can remember things from years ago, but not something I did an hour ago. Senility creeping up on me.

John

 

[Brian Rupnow]

John--No offence taken. I would far rather have someone warn me of a hazard I was aware of, than have someone assume I knew what I was doing and stand by while I damaged myself!!!

 

[Brian Rupnow]

Its Arrived. It came in today, and I brought it home in my pickup truck. Its a heavy little devil, weighs in at about 300 pounds. The bed is 7" x 19.75". I just took inventory of all the scrap angle and square tubing I have left over from various projects, and determined that I have enough to weld up a good base on the weekend.

 

[CrewCab]

That looks like a nice piece of Kit Brian 8) ............. enjoy getting to know it and above all, have fun

CC

 

[Brian Rupnow]

I had to take some time away from the steam engine project to install my new milling machine, but I have made a flywheel---and man, what a flywheel it is!!! I had a peice of mild steel shaft about 3" in diameter, and no brass or aluminum, so I made my flywheel from steel. I have to clean up the bore a little bit, and a bit of polishing to do, and Oh yes, drill and tap for a set screw, but other than that its done. but my, oh my, its a heavy little sucker.I may drill a series of lightening holes in it, but really, for the amount of material that lightening holes actually remove, it may not be worth the bother. I am not sure what the consequences are of running such a beefy flywheel, other than accelerated bearing wear, but methinks it will probably let the finished engine run a bit more slowly, because of the inertial effects.

 

[bretk]

Brian,

I've found the heavier the better, More inertia = slower running

-Bret

 

[Brian Rupnow]

We're getting there bit by bit!! My work day ends at about 3:30, and my wife doesn't get home from her job untill about 5:00, so I get about 1 1/2 hours a day to play machinist. This afternoon I finished the main bearing and the cylinder end cap. I will soon be finished all the lathe turned parts, and then I have to figure out where to start on my milling machine.

 

[bretk]

Brian,

I noticed your metric to english conversions on the drawings ;D Once you are done, would you mind passing those numbers on? I was thinking about doing the engine too, perhaps building two, one with my wife (that may be an ill conceived notion, but it might interest her a little in what I do "down there") So your proofing the engine in english measurements would save a few grey hairs :big:

Thanks, Bret

 

[Brian Rupnow]

bretk--I just keep 25.4 stored on my calculator. Any metric dimension (in millimeters) divided by 25.4 will give you the British Imperial equivalent to as many decimal places as your calculator will display.

 

[bretk]

Brian,

I agree 25.4 is a handy number but sometimes bolt hles and clearances just aren't quite the same when you are debugging a steam engine. (been there, dun that) so it's nice to have a pathfinder at times 8)

-Bret

 

[Brian Rupnow]

I just completed milling the main "frame" from aluminum flatbar. This is my first ever milling project, and I am very pleased. I made the frame much thicker in the area where the main bearing fits, because my steel flywheel is so heavy that I wanted the full thickness to support the full length of the brass bearing.