Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[Bernhard]

hey
i was thinking to bay a littel Twin Oscillating  steam engine,,maby a ACS Sandy's  Taipan,,i can get a nearly new one for 240£,,,whas and are they eny good,,,,or maby find a Stuart or Cheddar,,,bot i will like one there don't use a lot of steam,,,eny ides,,,,,,,,,,,
Regards Bernhard

[kno3]

If you can find a Cheddar Puffin (2 cylinders in line) or Pelican (v-twin), they are powerful runners (both 11 mm bore and stroke) and very compact. I have both and am very pleased. Besides, unlike other oscillators the cylinder shape is nice, with bolts etc.
I've never seen the Taipan though. Any pictures?

I don't know if Nick Monahan makes the oscillator he had on his website any more or not, but it sure looked nice.

[Underpressure]

£240 for an ACS engine is a good price. I did see a Cheddar Puffin sell for less on ebay recently, but from the pictures shown, it appeared to have a warped base.

The Puffin and Pintail are still available from Stuart, but at a price, I also like the look of the Graupner oscillator although I have not seen one in the metal.

What size boat are you thinking about, as that will have a bearing on the engine and the amount of steam it will use.

Neil

[Bunkerbarge]

I'm afraid Bernard that you are stuck with the fact that an oscillator will always use more steam for a required power but it all depends of course on how you use the model and how big it is.  The benefits are the compactness and power to weight ratio and if you don't go thrashing it around the pond on full power will give you a neat reliable propulsion unit.

Puffins and Pelicans are still around on eBay occassionally as are Hemmens Richmonds and, as Neil has said the Graupner units are a neat little twin oscillator but they are of Chinese manufacture.

An ACS is a well engineered little twin and £240.00 is a good price for it.  As always it depends on the condition but most defects can be sorted out easily.

[Bernhard]

hey.....Thanks......yes i have the richmond..bot i have to send the one cylinder to John H.. it is 85 cm,,boat,,,,,,LAUNCH.......I  did have a graham 2 cylinder in before,,,bot i will like it to work with only 2 servo in,,
i can only find this photos of the acs Taipan,,,,,,,

[Underpressure]

The ACS engine is very similar in many ways to the Puffin and Sandy filled a void left when the Cheddar factory closed and before Stuart recommenced manufacture of the Puffin and Pintail. It is very sad that he no longer manufactures.

If the boat is 850mm, then depending on the beam the ACS will work well and should give you  30 to 45 minute runs without any trouble at all. I am wracking my brain, but I seem to recall that when we did the 24hr event in Taunton (around 1996) with Endurance, we ran for 45 minute sessions before refilling water and oil and if you bear in mind we were running the boat fast the whole time, then that will give an indication of what an oscillator engine can do. Endurance is about a metre long and we were using a standard Puffin with horizontal boiler.

I run a Puffin engine and boiler in an Antheo tug with power to spare and run times easily in excess of 40 minutes.

BB, I did not realise the Graupner engine was Chinese, you learn something new every day.

Anyone know anything about the Clyde oscillator ? (and yes, I have seen the other threads).

Neil

[MONAHAN STEAM MODELS]

The ACS oscillators are great engines. The quality is top notch. I recently posted a link to an ACS horizontal steam plant that was forsale on flea bay.

You really can't go wrong with a Cheddar Puffin or Pintail engine as these are high quality too. It's worth digging around to find one. There are still plenty of them out there. I will keep my eyes open for one if you like?

I don't know if Nick Monahan makes the oscillator he had on his website any more or not, but it sure looked nice.

Kno3, Thank you for your kind compliments. We still make the three types of oscillator engines that were shown in the past on our website but you are correct, they are not shown currently on our website. They are out of stock and have been for sometime due to the fact we only made a small handful. Lately in between the busy times we have been machining the bits and pieces again so they should become available shortly.

[andywright]

I have recently sent a couple of emails to the company that was supposed to have taken over from ACS, but never got a reply. I like the look of the Saipan, but all sorted now with a Graham TRV1A.

[steamboatmodel]

I have recently sent a couple of emails to the company that was supposed to have taken over from ACS, but never got a reply. I like the look of the Saipan, but all sorted now with a Graham TRV1A.

What Company was supposed to take over from ACS?
Regards,
Gerald.

[Bernhard]

Here is ACS Sandys Engine............. have only be broken in,,,,,,,,,,220 euros ...........so i have bought this one........maby it will use less steam,,than the Richmond do,,?....

[Underpressure]

What a super engine, you have got yourself a real bargain 

Neil

[HS93 (RIP)]

Here is ACS Sandys Engine............. have only be broken in,,,,,,,,,,220 euros ...........so i have bought this one........maby it will use less steam,,than the Richmond do,,?....

that one looks really nice ,It will be interesting to see the difference in steam use ,the ACS engines have a good reputation.and the mating surfaces are made of the same material.

Peter

[Bunkerbarge]

Bernard, although leakage does play a small part in the differences in steam requirements between oscillators and slide or piston valve engines the fact that oscillators require more steam is much more as a result of the engine configuration.  Oscillators, being reversible, must have thier ports drilled symetrically in the entablature.  This means that in either direction the steam is being admitted partly on the rising stroke thus actually slowing the piston down.

Slide and piston valve engines though can have the valves arranged to admit the steam at a much more efficient part of the stroke, making then far more efficient, but they then of course require reversing gear to change the valve timing to run in the other direction.

Bottom line is that oscillators will use more steam than an equivilent output slide or piston valve engine however thier compactness and simple and reliable configuration does mean they are quite often used in an enclosed model. 

[tonyH]

Does anyone come upon the old York twin?
Needed a big boiler and took time to get hot BUT was a real beauty running.

Tony

[Underpressure]

Bernard, although leakage does play a small part in the differences in steam requirements between oscillators and slide or piston valve engines the fact that oscillators require more steam is much more as a result of the engine configuration.  Oscillators, being reversible, must have thier ports drilled symetrically in the entablature.  This means that in either direction the steam is being admitted partly on the rising stroke thus actually slowing the piston down.

Slide and piston valve engines though can have the valves arranged to admit the steam at a much more efficient part of the stroke, making then far more efficient, but they then of course require reversing gear to change the valve timing to run in the other direction.

Bottom line is that oscillators will use more steam than an equivilent output slide or piston valve engine however thier compactness and simple and reliable configuration does mean they are quite often used in an enclosed model. 

There is a further advantage of the oscillator. Due to it's simplicity and relative lack of moving parts they are invariably much cheaper to make / buy. The exception is of course the TVR1A, but all other valved engines, like the Monahan, Anton or Stuart engines are more expensive to buy than any oscillator. They also tend to have slightly more complex steam requirements and are also usually bigger, although there are some smaller engines, like the Monahan Sparrow.

The fact that in the last few years we have lost four manufacturers of oscillator engines (Cheddar, SVS, ACS and Tony Green) has unfortunately got to tell us something and I would hazard a guess that there are a fair few bargains like Bernhard's sitting in draws and at the back of workshops, leftover from the 'steam for all' trend that Cheddar created, but I digress.

Horses for courses I think, or whatever takes you liking.

[AlexC]

Hi Guy's

Bernhard,

What you have there is an ACS 'ASP' twin not a 'TAIPAN'. It is 5/16" bore x 3/8" stroke.

HS93 (Peter),

The mating surfaces on ACS engines are not made from the same material... the 'STANDARD' is made from Silicone Brass and the cylinders and moving port faces are cast in Gunmetal (as is the reversing valve)... an excellent matching pair for long working life.

B.Barge (Richard),

What you say about the symetrical porting on a oscillating engine is quite true, however, you do not get steam being admitted for any part of the UP stroke slowing down the piston.
When the piston is at either TDC or BDC (assuming a double acting engine) then BOTH inlet and exhaust ports are closed, since the single port in the moving cylinder face actually falls within the gap between the 2 ports drilled into the fixed port face.
Usually this gap is slightly larger (a few thou) than the cylinder port dia, hence, the piston generally has to be just past TDC or BDC to actually admit steam. The same applies to the exhaust port.
On a well designed oscillator you get steam being admitted for approx 99% of the total stroke and the exhaust port (for the same cylinder, but opposite side of the piston) is open for the same time. Thus no use is made of the expansive capability of the steam.
Reversing is done by swapping the STEAM ports and the EXHAUST ports.

The same is true of SOME piston valve engines, such as the HEMMENS 'CATON' which is designed with a LINE on LINE piston valves (having no meaningfull lap nor lead) and which is also reversed by PORT SWAPPING.
This also makes NO expansive use of the steam.

More sophisticated engines, 'MONAHAN', 'ANTON' etc, which employ 'Stephenson's link reversing valve gear, or the 'GRAHAM TVR1' which uses 'Hackworth' valve gear, do make some use of steam expansion since they admit steam at the start of a stroke but the valve gear cuts of the steam supply at around 65% - 85% of the stroke (depending upon expansion link position on Stephenson equipped engines or the slide angle on the Hackworth) and some of the remaining stroke (but not all of it) is made using steam expansion alone. Usually, due to valve lap/lead being employed, the exhaust port actually opens just before the stroke completes.

Hope this clears things up a bit.

HAPPY CHRISTMAS and NEW YEAR to everyone.

AlexC.

[gondolier88]

Good to hear from you AlexC

Greg

[Bunkerbarge]

Many thanks Alex for a considerably better explanation than mine!

[Bernhard]

Hi.........Thanks Alex,,,,,,OK.....i was just told it was a Taipan,,,,bot i can live with another name..............Thanks for the information

Regards Bernhard

[andywright]

What Company was supposed to take over from ACS?
Regards,
Gerald.

Tony Green models took over I believe, thats who I sent the emails to any way.

[HS93 (RIP)]

Tony Green models took over I believe, thats who I sent the emails to any way.

 I Though Tony Green had taken over SVS, but that will now be lost with the sad loss of Mr Green recently.

Peter

[mogogear]

I am unsure of the year my Graupner twin was made and where- I have heard China and or Germany but it sure is another in this line of style twin oscillators..

She runs very well and pushes my 40" launch with no problem. I have taken it apart an the cylinders and engine body are all brass. It does have a R sitting in a chevron emblem stamped on the side of the central body--

I do not know if that means Regner or a Chinese R for something else



Good luck with the new Twin Bernhard!!

[Bernhard]

Thanks Mo.......i like your engine,,nice green color to...,,and the idea with this engines ,they work with only 2 servo...and i have see many, have be so happy with them fore years...so it was time fore me to try one
here is a Graupner running

http://www.youtube.com/watch?v=NMhCh16jqGM

Regards <Bernhard

[Bernhard]

here is a regner working
http://www.youtube.com/watch?v=OeJBH4aFLJU&feature=PlayList&p=855B383C357C860D&playnext=1&playnext_from=PL&index=4

[Underpressure]

Anybody know anything about the Regner marine engines?

I don't know if they are imported into the UK, although the garden loco's are.

The oscillators look very simply made and the V twin looks like quite a useful little engine.

Neil