Oscillating I.C. Engine

[Cogsy]

In my head I thought it was going to be a lot bigger than it is - or you've got yourself some comically oversize scissors and pencils... Looking great so far.

 

[Mechanicboy]

Hi Brian
nice project, but the rotating mass transfer is so big it will be worst then a
grasshopper.

cheers
Luc

Nice to leveling of asphalt.

 

[Brian Rupnow]

And now you know how I spent my Sunday, or at least a good portion of it. Lets see--I started at 6:00 this morning and it's 2:00 PM now. That's 8 hours, but I took half an hour to eat and 21/2 hours to model a conveyor for a customer. so---That cylinder head is a five hour part. It isn't perfect, but it's good!!!

 

[Barnbikes]

What size spark plug are you using?

 

[Mechanicboy]

I can see the spark plug is a NKG 6-CM, right?

 

[Brian Rupnow]

Right!! it has an M10 x 1 metric thread. I can buy them at the local auto parts store. To go any smaller than that, I have to order them from a model engine parts supplier and have them shipped to me.

 

[Brian Rupnow]

This morning I built the two stands that the cylinder sets in to "oscillate". What you don't see in the pictures are the bronze bushings I pressed/loctited into the aluminum stands. On the thick stand, there is a steel ball that fits into a coned recess in the pivot shaft, and a threaded set-screw in the stand that puts some pre-load on the cylinder so it sets up tight against an o-ring seal which is buried inside the other pivot stand. In he other angular support stand you can see the two #4-40 threaded holes that the carburetor and valve body attaches to.

 

[jimjam66]

Great progress and a unique (to me, anyway) idea. Would you see an application for this, Brian, or is it a 'lets see whats possible' thing?

 

[Brian Rupnow]

JimJam--As I pointed out at the beginning of this thread, the original design for this engine came from Philip Duclos. I believe this falls into the category of "Novelty Engine". I don't really see any practical application for an engine like this, other than for fun. It is the "uniqueness" that attracted me.----Brian

 

[bmac2]

Hi Brian
This engine is very close to the “WHAT THE? ” category. Great work and thanks for posting.

David: Most of these model engines are just smile generators. For your first runner I’d suggest a glass of wine and I’ll bet it can go right up to snort and chuckle.Thm:

 

[Brian Rupnow]

By the way---Did I ever mention how much I dislike machining steel?? I am badly spoiled by using mostly aluminum and brass for the things I build. My relatively small mill likes it that way too. However---There are times when nothing will do but steel. Such is the case with the piece in the foreground of the picture. The 1/2" hole gets an oilite bushing to support the crankshaft, the 1/4" hole in the bottom of the counterbore gets a stationary camshaft, the counterbore is where the cam attached to the large timing gear lives, and the horizontal slot is where a bronze pushrod goes. The pushrod is rectangular, and has a slot in two opposing sides which fits over the steel slot to guide and support it, and one end rests against the cam. I didn't have any cold rolled steel to make this part, but I remembered seeing a rusty, crusty piece of 1" thick hot rolled in my "metal storage bin". I did a bit of searching and found it, and was able to carve this fairly reasonable piece out of it. I still have a lot of work to do to finish it, but it is an interesting part of the engine.

 

[Swifty]

Coming along great Brian, but I'm with you when it comes to machining steel, had my fill of it during 35 years of toolmaking, aluminium is so much better to work with.

Paul.

 

[barnesrickw]

Had a rough patch with steel just this week. Aluminum is much more fun.

 

[deverett]

...and much lighter!

Dave
The Emerald Isle

 

[Brian Rupnow]

I've had so much unexpected "drop in" engineering design work, that I am considering buying a new milling machine. (To get rid of some of the money!!) My BusyBee Craftex CT129 is still going strong, but I would like something a bit bigger, stronger, newer. I don't want a knee mill, I am quite satisfied with the square column mill-drills that are available. Busy bee has a new 1 HP mill, with a larger x and y movement and an R8 spindle taper. It is 110 volt, which is a good thing because I don't have 220 volt available in my small machine shop. Of course, this means that along with the mill, I will have to buy a new boring head, because mine has an MT2 taper and it is not the removable shank type. The mill comes with a chuck, but I would have to buy a 1/2"-R8 collet and a 3/8" R8 collet to hold my milling cutters, and I think it's about time I had a new electric center finder. The price for everything including the sales tax is just under $3000, and my wife says "Go ahead!" Damn, I love that woman!!! I just came home and measured the space available in my machine shop, and the new mill is so much bigger than what I have that either the bandsaw or the 1" belt sander or maybe both will have to move out to the main garage. My "machine shop" is a seven foot square annex of one corner of my design office that never got used---it had an enormous old drafting table in it that never got used, so when I began this machining hobby 5 years ago the drafting table went and a wall was built to separate the machining area from the office area. I may be about to outgrow things---

 

[bazmak]

Congratulations on having a very understanding Wife Brian
I dont know how old you are but as you get older you realise you
cant take it with.The old adage,i will save up for it goes out of the window
If you can afford it then buy it and enjoy it now Regards barry

 

[Brian Rupnow]

Barry--I'll be 69 in July. I've been very fortunate to have fallen into a ton of work this spring, which generated the money to buy a new mill. I am scrambling like mad now, trying to figure out where to put a new mill if I buy one. My current mill is 29 1/2" from end to end of handles on the X axis. The mill I am considering buying is 45" end to end of the handles. I could move my bandsaw out into the main garage and that would free up sufficient room in the machine shop, but next winter when it's 20 below zero in my main garage I wouldn't like it so much.-----Brian

 

[bazmak]

Keep the mill and lathe together.If the bandsaw gets less use for shorter periods move it.I have similar problems,you have to prioritise space to machine.My bandsaw,grinders and linisher are moved to out of the way spaces and brought out as i need them for short term use.I am 68 and bought the new mill and lathe,enjoy now while you can.I got the R8/ef32 collet set
for $100,made a chuck for the lathe now i can grip anything from 2 to 20mm
in both machines.If your getting a new mill then spend a bit more on extras
If your short we can have a whipround. Regards barry

 

[RonGinger]

$3000 sounds high- have you looked at the Grizzly G0704? I bought one a year ago and really like it- it is R8 and has a table just about the same size as my Jet knee mill. Its only about $1200

I don't know about the import issues of getting a Grizzly into Canada, but I bet if you drove down to the store in PA and brought one home in your car it wold not be bad. And a nice road trip as well.

 

[Brian Rupnow]

I couldn't let the whole weekend get away without building at least one part for the engine. We now have an outboard crankshaft support complete with bronze bushing (and no, I didn't use Loctite on it.) I have had a crazy/busy weekend working for a customer, doing 8 hours work which I had estimated and quoted at 4 hours work--(Hate it when that happens), painting headboards for grandkids new beds, and cutting dangerous trees out of the fenceline between me and the neighbour. There are two holes yet to be tapped in that aluminum part I just made for ignition points, but I will wait till I have the ignition points in my hand to check the hole position first.