# Double action oscillator sources?



## gwscheil (Aug 6, 2008)

Does anyone have a good (cheap) source of simple double action oscillator cylinders. Like hopefully ready to use, no machining needed and a useful size for 1:20 scale? I see ads for several, but many require machining, or dimensions are not stated, or the prices are steep. My recent BAGRS engine may need an upgrade from single action.


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## dwegmull (Jan 2, 2008)

Hi George, 
Do you need a one or two cylinder engine? 
One cylinder: Regner Oszi $173 
Two cylinders: Regner Venus (V2): $297 
Both are available in the US from the Train Department. http://www.traindept.com/lsboats.html
I realize this may be more money than you are willing to spend but I can assure you that these are top quality (CNC machined) engines that will last. 
One more thing: Is your boiler up to the task of supplying the extra steam? As an alternative, you could use a second single acting cylinder (Midwest), timed 180 degree from the first one.


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## weaverc (Jan 2, 2008)

George,
I think what you are looking for is an *Osmotor*. I found a rare Steam Motor made by the late Colin Binnie. I've seen others similar, but you have to search for one used as I've not seen any new ones other than the expensive one by Regner. The one I have is geared and I attached a BAGRS type chain drive to it to give me the power I need to run my very heavy 7/8ths scale tram. It is a reliable, good running motor, but VERY fast, even at 10psi, hence the gearing and chain reduction. One solution may be to combine two Midwest motors into an Osmotor configuration. One other consideration for a motor might be a one or two cylinder kit from Graham. I had good luck with the one cylinder model, the VR1a, which is fun to build, relatively inexpensive. You can it see at: http://www.grahamind.com/vr1a.html
or others at:
http://www.grahamind.com/downloads.html


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## msimpson (Jan 5, 2009)

PM Research, http://www.pmresearchinc.com/store/home.php?cat=4 , charges $67 for a fully machined, double-acting, one-cylinder kit, with stand and flywheel, #2Am (with other kits and unmachined kits also available). A friend of mine is pleased with the V-twin kit he got from them, for a boat. 1/2" bore by 3/4" stroke, about 4.5 inches high and with a 2.25 inch flywheel.

I built a Graham Industries VR1A some years ago, one cyllinder, double acting, slide valve, Stepehson's valve gear, with flywheel, $119. Works good on air but have never tried it on steam. http://www.grahamind.com/ This one is fully machined and only requires polishing and assembly, but at least one of their kits in unmachined. 

PPS Models sells replacement and improvement parts for Mamods and IP Janes. A pair of the improved double-acting oscillating cylinders, ready to bolt on, sells for 36 pounds plus postage and an improved reversing valve is 20 pounds. http://www.pps-steam-models.co.uk/ I have been pleased in several dealings with PPS and have both the improved cylinders and reversing valve sitting in a box with a Jane awaiting ressurection. (Given the aggravation and expense of overseas trade, I prefer the better cylidners to the original, cheaper product.) 

If you search the book sites, eBay, and the web, you can find several books explaining the building of single and double-acting cylinders with limited tools. The double acting require a lathe or a liot of filing, but the single acting can be made from K&S tubing. Before you dismiss this, Bob Pope (of the gas electric locomotives) has built some very nice, very precise oscillators in just this fashion for boats. 

You might also check out marc Horovitz's Sidestreet Bannerworks site. http://sidestreetbannerworks.com/ Several of the engines he built himself are based upon simple oscillators. 

Best regards, Mike


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## gwscheil (Aug 6, 2008)

A simple system like my IP Jane cylinder is closest to what I am looking for. A Regner Willi replacement cylinder would also work but is more expensive. Most of the others mentioned would tower over my BAGRS which is already top heavy.


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## Steve Shyvers (Jan 2, 2008)

George, 

Several years ago I built an engine for my BAGRS loco using two Midwest single-acting cylinders 180 degrees out of phase. I made the frame from aluminum and brass, and bought the Midwest pistons, cylinders, flywheel, and crank wheel from Midwest. (There was an individual parts list with prices in the Midwest Model VI instructions.) If you'd like I could try to find a photo of the engine and post it. 

My two-cylinder engine isn't self-starting, and there's no reverse, but it is surprisingly powerful for it's extremely small "displacement". It's power I credit to many hours of running in one direction only, which has effectively "lapped" the piston to the cylinder. That's my theory, anyway. 

The engine drives a jackshaft through the standard BAGRS reduction sprockets, and then the jackshaft drives both axles through 1:1 miter gears. This extra load is no problem for the two-cylinder engine, and the four-wheel drive makes it sure-footed even on oily or uneven track. The boiler is the standard Midwest boiler fired by two alcohol wick burners. The steam line from the boiler passes through the firebox between the two alcohol flames to provide a tiny bit of steam drying before the steam goes to the lubricator and engine. It's a fun loco to watch running. 

Steve


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