Adding a reduction sheave to my double wobbler

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Brian Rupnow

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I want to be able to drive something with my steam engine, but first of all I need to have some kind of torque multiplier system that will slow it down and increase the torque. Based on what I have found in my shorts rack, I am going to add what I have shown here. The dark blue part will begin life as a peice of 3/4" x 2" aluminum bar, and the pulley will be made from a peice of 1" x 3.5" aluminum flat bar. The bolt head which is visible holding the pulley in place is a 1/4" dia. x 1" lg. shoulder bolt. The belt will be ??? (not sure yet). The system as shown will give me an approximate 3.5:1 reduction in speed, plus will increase the torque at the small output side of the new sheave by the same ratio.

double acting wobbler with reduction pulleys (Small).jpg
 
Got the dark blue part made today. I still have to drill and tap a pair of 1/4"-20 holes in it, but will wait untill I get the green pulley made and mounted to it. The threaded hole that is already in the part has no purpose--it was already there in a peice of aluminum I am "salvaging".


REDUCTION BASE001 (Small).JPG
 
Cool

What do you plan to run with your reduction and engine?
 
Note from Myself to Myself---Just because something can be done, doesn't mean it should be done!!! I had just enough 1" x 3 1/2" aluminum bar left over to make the large pulley out of. ---I forgot how friggin' much machining there was in reducing a bar that size to a pulley 3 1/2" diameter x 1/4" thick with an extended hub. I have enough aluminum swarf to fill a bushel basket---

PULLEY IN PROCESS001 (Small).JPG
 
TaDa!!!!--And there we have it---a finished pulley. The brass rod is a light press fit, helped out with a bit of Loctite. Tomorrow I will cut the brass rod off flush with the end of the pulley and drill the center out to fit the shoulder bolt which is laying beside the pulley in the picture.

PULLEY FINISHED001 (Small).JPG
 
Please post lots of pictures of your bubble machine. I know a guy that wants to build one;o) Nice job on that pulley!

Wes
 
WOW!!! You should see that sucker go!!! I stuck an elastic band on for a temporary belt. The first time I tried it the belt kept jumping off because I had a very slight misalignment problem. Thank God for the milling machine. I put a 1/4" end mill in and slotted the offending bolt hole in the base by about .030". That straightened everything out, and the belt stays on. You can actually feel the increase in torque by resting your finger like a brake on the small diameter of the new pulley. It takes a lot more pressure to stall out the machine than if you press directly on the flywheel pulley which is roughly the same diameter. the reduction in speed is very visible as well.

PULLEY ON AND WORKING001 (Small).JPG
 
Brian,

On my horizontal paddle engines I use 3 to 1 gearing, they only have a double acting twin cylinder 10mm bore, but at 5psi they just cannot be stopped by hand.

John

3 to 1 reduction.JPG
 
Brian Rupnow said:
John--That it a beautifull engine. Where the heck is the flywheel???

Self starting, the flywheel is the paddles. I was confused at first, then paddle wheel got me ;) I think I'm right?

John--if you made that yourself you are a great machinist. Maybe a little too much time on your hands
 
No need for a flywheel.

I had a fairly long discussion on another site that involved our steam man Sandy, about the use of flywheels.

On a double acting twin such as this, they are not needed, I have attached a pic of the vertical as well, it will run just as well without the flywheel, it is really there only because people expect to see a flywheel. They are basically the same engine with different mounts, and can be converted back to the opposite in less than an hour.

It is small batches of engines such as these that keep my workshop running. It has to pay for itself.

People don't realise just how much power these little engines have.

John

BTW Ranger, these are made from materials from the scrapyard and salvaged bits, except for the fasteners, o-rings and a bit of copper tube.

Pair together.JPG
 
Guys, you are really getting me going on powering something with my recently completed engine. Great job on the pulley Brian :bow:, and thanks for the helpful info John :bow:.

Cheers,
Phil
 
Nice addition to the engine Brian.... Can't wait to see the bubble machine!!


Good quality video too. You'll be editing in titles before you know it ;D




Thank you for the post too Brian, soon as I build a big enough engine I will think about ways of driving things off it too ;D





Ralph.
 
Erm..... What's that then?? ???

The start of a 'bubble maker deluxe' ? ;D





Ralph.
 

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