|
|
|
|
|
|
|
Reply to George-Type of engine
Hi George:
The build has started on the Preston's steam plant. It will be a 2-stroke, fixed cut-off long throw scale model of Preston's actual Gillette & Eaton steam engine. Trips up to Anacortes, WA have been made to photograph, study and measure W.T. Preston's engine and boiler in preparation for this part of the build. I have enlarged the bore bigger than scale to facilitate slow speed operation. Calculations have been made to operate the engine at a maximum of 40-psig giving me a max rotational speed of 110rpm. At max speed, the engine will need about 330 cu-in of steam per minute. The engine will have a bore of .625" (5/8") and stroke of 2.25", X 2, which is scale. I kept the stroke scale so that the cranks will be the proper size out on the paddlewheel. Pitman arms will be directly connected via cross heads to the pistons and paddle cranks. eccentrics on the paddle shaft will control valve action through reversing gear. We have the CAD drawings completed and they are being fed to a 3D printer to make the prototype parts. These plastic parts will then be used to make highly accurate sand casting molds and from that, the iron castings. Each cylinder will have two servo operated drain valves at either end. Mike in Edmonds |
|
|
|
|
|
Response- Gary
Thanks. I'm glad I didn't go with electric propulsion. This will be the model's crowning glory. Not just a live steam engine, but a scale model of W.T. Preston's engine. After watching two of our club members run their steam launches at the Seattle Yacht Club Opening Day festivities yesterday, I was pleased to hear people stopping by being very impressed with the steam boats. More to come...
Mike |
|
|
|
|
||
|
|
Quote:
Lee showed me his acquired Topaz!! Spectacular boat to have and run!! I will be up for the club regatta on June 16..come hell or high water..I look forward to meeting you!! Steaming has such different challenges -- that is what makes it so engaging and fun for me |
|
|
||
|
|
||
|
|
Quote:
We'd love to have you visit. We meet every Thursday morning from 10am to 11:30am for a "tech talk" coffee at Galaxy Hobby in Lynnwood. We also have our monthly club meetings the first Thursday of the month at the same location, 7pm to 9pm. Our club website also lists our Fun Floats. They are usually at Bellevue City Park pond. Come on up... Mike in Edmonds |
|
|
||
|
|
|
|
|
Any suggestions on R/Cing the 4 cylinder drain valves to prevent hydrolock? Is it necessary? I don't want to hand crank the paddlewheel to remove condensate in the engine and would rather be able to open those valves for a few revolutions at startup, then close them once drained. I'll have plenty of channels to do this. All I'll need is an on/off servo throw.
Mike[/QUOTE] Mike, The engine in my tug is a Stuart D10 and has no condensate drain valves. I can start it in 2- ways. 1- Feed in steam and turn the prop over until it starts and the condensate is cleared. 2- The Stevenson reverse gear is connected to a 15kg pull servo which is set at mid point, to start I feed in steam and move the arm back and forth which twitches the engine back and forth, clears the condensate and away it goes with no need to turn over the prop. You have the advantage of your engine being a piston valve which if the reverse lever is connected the same way as mine you will clear the condensate without turning the paddle wheel over by hand. It may be easier to sacrifice exact scale and make a reversing valve that can ether direct the steam to the engine for forward motion or switch over so that the steam enters the exhaust and will drive it in reverse, but then you may want to be as near to scale as possible. Wilesco steam engines are all piston valves and like all piston valve model engines eventually leak steam. Here are some pics of a piston valve twin that I built some years ago and has no drain valves, to prevent steam leakage from the valve I made a screwed plug for the top and extended the valve box at the bottom to allow a silicone 'O' ring on the valve rod to be installed which stopped any leaks and it had a reversing valve to switch the steam. Also a Saito single cylinder that I converted to run ether way with a reversing valve, this type of valve also allows speed control of the engine. Hope this helps, if I am not too clear on my explanation don't hesitate to ask. George.
|
|
|
|
|
|
|
|
Mo ,
While I am on line, what is a SUPER SOAKER ? Thanks for the compliment on my old lady ( the tug not her indoors ) I am in the process of running in the new engine in between building a Stuart LAUNCH ENGINE , trying to keep the garden tidy and running back and forth to hospital with my DUKE OF ARGYLLS George. |
|
|
|
| Thread Tools | |
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Sold Graupner Glasgow, Steam Plant, Upgrades, LAST CHANCE | ir3 | Boats (FS/W) | 3 | Feb 20, 2012 11:41 AM |
| For Sale Graupner Glasgow, Steam Plant, Upgrades, REDUCED | ir3 | Boats (FS/W) | 6 | Feb 06, 2012 08:30 AM |
| Help! Cheddar Puffin steam plant | dunc2504 | Scale Boats | 10 | May 30, 2011 02:32 AM |
| Discussion Steam plant for Brooklyn Tug | peconic steam | Steam Boats | 16 | Jan 07, 2010 03:52 PM |
| Wanted cheddar puffin steam plant | dunc2504 | Boats (FS/W) | 1 | Jun 13, 2008 03:32 AM |