Triple Expansion Engine - Elliott Bay

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Triple Expansion Engine - Elliott Bay

Post by csonics » Wed Nov 18, 2009 4:46 pm

Posted on behalf of Maltelec:

Maltelec
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Posted: Sun Sep 23, 2007 12:09 pm Post subject: Triple Expansion Engine - Elliott Bay

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Maltelec
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Posted: Thu Sep 27, 2007 3:54 pm Post subject:
More pictures of the part-machined bearings and the engine bed

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KNO3
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Posted: Thu Sep 27, 2007 4:10 pm Post subject:
What is this engine for and what boiler is it going to have?
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Edward
Lighting the Boiler


Joined: 01 Oct 2007
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Location: Ambleside, Cumbria, UK
Posted: Mon Oct 01, 2007 2:16 pm Post subject:
It's for a 32' steam launch currently being fitted out. I hope the boiler will be a vertical firetube wet firebox with 141 x 3/4" id tubes, grate area 3.142 sq ft.
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Edward
Lighting the Boiler


Joined: 01 Oct 2007
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Location: Ambleside, Cumbria, UK
Posted: Sat Oct 06, 2007 12:51 pm Post subject:
It ocurred to me that the estimated steam consumption figures for this triple might be of interest. As a general rule of thumb triples need a steam pressure of 150+psi; of course a lot depends on the ratios between the volumes of the cylinders and also the vacuum in the condenser.
The cylinder dimensions are 2 3/4"+ 4 3/8"+6 1/2" x 4".
Estimated steam consumption is as follows:
At 180psi , 500rpm=254 lbs per hour, 250rpm=127 lbs per hour.
At 200psi , 500rpm=275 lbs per hour, 250rpm=138 lbs per hour.
I hope these figures are of interest. If anyone can spot any flaws I'd be grateful to receive their views.
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Maltelec
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Posted: Sat Oct 20, 2007 10:28 am Post subject:
Here is a picture of the coloumns polished and ready to go on the bed plate

Image

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Edward
Lighting the Boiler


Joined: 01 Oct 2007
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Posted: Sat Oct 20, 2007 10:55 am Post subject:
I bet your mother was deliriously happy ( or should that be hysterical ) to have them in her kitchen.
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Maltelec
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Posted: Sat Oct 20, 2007 11:32 am Post subject:
I recon she is used to it by now

I've got a video and another picture
[Youtube]http://uk.youtube.com/watch?v=TPq5MpGkhe4[/Youtube]
Image

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Maltelec
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Posted: Tue Nov 20, 2007 1:35 pm Post subject:
2 more pictures from today:

Image

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Maltelec
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Posted: Sun Dec 16, 2007 5:52 am Post subject:
More pictures of the progress

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marinesteam
Lighting the Boiler


Joined: 28 Nov 2007
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Location: Colorado, USA
Posted: Mon Dec 17, 2007 9:39 pm Post subject: Looking great
Hello,

I would like know what type of steel you are using for the columns and what finish (if any) has been or is going to be applied? Also, do you have any concerns about corrosion if they will be left bare?

The engine looks likes it's coming along well. I know there is quite a few more parts in the EB triple than in the York that I am building, I bet it's quite a thrill to see it coming together. I can't wait until I progress that far.

Ken
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steamboatjack
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Joined: 01 Oct 2007
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Posted: Wed Dec 19, 2007 3:35 am Post subject: columns
Ken,

Hi the columns are of stainless steel, 303 is best as it’s free cutting. I also use only stainless nuts as it’s not worth doing otherwise, the only exception being if higher tensile fasteners are required, A2 stainless is ok but not as strong as some people think, also its most important to use a lubricant on the threads.
Rust I am afraid is a pain for all steam boaters and there is no easy answer, I kept my boat Grayling in a boathouse on Windermere for a number of years with no rust at all due to the fairly slow rate of temperature change, on the trailer its another matter, I really need to win the lotto to buy a boat house in the lakes. Any pics of the York compound available?
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marinesteam
Lighting the Boiler


Joined: 28 Nov 2007
Posts: 39
Location: Colorado, USA
Posted: Wed Dec 19, 2007 11:41 am Post subject:
Hello,

I currently do not have any pics of the York engine. I have been working on some other projects while working up the nerve to start machining the castings of the York. I have however begun to work on some of the parts of the engine. I am fettling the castings prior to machining. The intent is to finish all of the bronze bright and figured that the best approach would be to do most of the major smoothing of the castings to the point of being ready for polishing, then machining the pieces and completing polishing afterward. The idea is that I am sure that I will ding a casting during machining and that can be removed easily without spoiling the finish and I can still feel like I am working on the engine in the mean time. I am also intending to hone my machining skills on the bar stock parts before tackling the machining of the castings.

I hadn't considered stainless for the steel components. I am still deciding what finish would look good with the bronze. Currently, I am leaning toward polished steel for the front columns (the York has cast iron rear columns & guides) so stainless has some merit. I will probably use a dark brown parkerized finish for the remaining steel components.

I do plan on posting pics of the York engine as I make progress.

Thanks

Ken
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artemis
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Joined: 24 Sep 2007
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Location: Portland, OR, USA
Posted: Thu Mar 20, 2008 5:23 pm Post subject:
Edward wrote:
It ocurred to me that the estimated steam consumption figures for this triple might be of interest. As a general rule of thumb triples need a steam pressure of 150+psi; of course a lot depends on the ratios between the volumes of the cylinders and also the vacuum in the condenser.
The cylinder dimensions are 2 3/4"+ 4 3/8"+6 1/2" x 4".
Estimated steam consumption is as follows:
At 180psi , 500rpm=254 lbs per hour, 250rpm=127 lbs per hour.
At 200psi , 500rpm=275 lbs per hour, 250rpm=138 lbs per hour.
I hope these figures are of interest. If anyone can spot any flaws I'd be grateful to receive their views.


Nothing wrong with the figures, but I would caution our cousins across the pond to remember than American engines tend to be "long legged" (ration of crank dia:conn rod length). This comes from a desire to reduce "angularity" and thus improve performance/valve events/economy. To turn these long legged engines (the York compound is another good example) over above 400rpm is to is to throw a lot of metal around at rather high speeds.

Ken Hall of Vancouver, BC - who built the first practical Elliott Bay Triple (Peter Cowie visited/corresponded with him a great deal) has his installed in a 23.5' Elliott Bay Hull. His boiler, a 49sq.ft. Ofeldt, provides steam to the engine at 185psi to produce approx. 8HP while turning a 20" x 34" propeller at 375rpm. I have ridden in Oesa many times since she was launched in 1997 - she always operates smoothly, quietly and reliably!

I hasten to add that Mr. Hall comes with excellent credentials being a retired LPE, steam, with a degree in Mech.Eng. steam from the U of BC and having designed and supervised the erection of many steam engines and boilers.
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Edward
Lighting the Boiler


Joined: 01 Oct 2007
Posts: 39
Location: Ambleside, Cumbria, UK
Posted: Tue Apr 22, 2008 6:10 pm Post subject:
Dear Artemis,
Your comment on high RPM is quite understood . When I posted my estimates for steam consumption I just picked nice round figures rather than what I intended to run at .
For me a lot of the attraction of steam is that you can see what's happening , so for normal cruising 200-350 RPM is plenty....of course it would be nice occassionally to to see what she can do....
Simpson Strickland produced a small triple of very similar size for which they claimed an output of 35 HP at 750 RPM and 350 PSI . I suspect this was IHP rather than on a brake , and I'm not sure what the engines' life would be at these RPM ! I believe my crank shaft has been spun at 1200 RPM and didn't shake the lathe to bits but I don't think my boiler would be quite up to that !
The boiler I intend to use , should it pass its next test , is a vertical firetube with a waterleg and has a heating surface of just over 36 sq ft. When it was built it was tested and certified for a working pressure of 200 PSI .
Traditional wisdom says one should get about 5lbs per hour from each sq ft of heating surface in firetube boilers ; I hope to get a bit more than that as the firebox is quite large (2' diameter X 13" high) but even so I doubt that I would be able to sustain more than 350-400 RPM and I don't think the coupling between engine and shaft with a 20"x36" prop would like much more.
If anyone is interested I'll post fuller details of the boiler so people can work out the output for themselves and let me know by how much my estimates are wrong.
Thanks for your observation/comment
Edward

Maltelec
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Location: Cumbria, UK
Posted: Wed Jun 18, 2008 4:59 pm Post subject:
Here is another video of the Triple:

http://www.youtube.com/watch?v=6fLbhBtpl0c
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Maltelec
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Posted: Wed Jun 18, 2008 5:09 pm Post subject:
And here are 2 of the latest pictures:

Image

Image

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Maltelec
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Joined: 23 Sep 2007
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Posted: Sun Oct 12, 2008 10:57 am Post subject:
Here are the latest pictures and a video:

Image

Image

Image

Image

Image


[Youtube]http://uk.youtube.com/watch?v=zRpmEa6hdwU[/Youtube]

cowiepeters
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Joined: 01 Jan 2008
Posts: 3
Location: Sydney, Australia
Posted: Sat Dec 06, 2008 12:11 am Post subject:
Dear John,

Great to see your progress!

Here are two photos of the back of my engine showing the LP receiver. I made mine from 1/1/2" copper with elbows silver soldered. The second photo was taken soon after I ran the engine on the dynamometer. The condenser setup might interest you.
Image
Image

I was contemplating screwed fittings but the dogleg required to get the exhaust from the LP valve chest down past the receiver and over the wayshaft led me to the copper approach.

Lagging will give you some headaches here!

Kind regards,

Peter Cowie
Sydney
Australia
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Maltelec
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Posted: Fri Dec 19, 2008 8:47 am Post subject:
Some more pictures:

Image
Image
Image

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steamboatjack
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Joined: 01 Oct 2007
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Posted: Thu Feb 19, 2009 7:00 am Post subject:
Pic shows some more progress on the first engine, machining the new eccentric rod top ends. The original S.G. iron castings have been rejected due to poor castings and insufficient machining allowance. The eccentric rods are being made in two parts from 230M07 (free cutting mild steel).
note the fixture made for this operation.

regards jack
Image

87gn@tahoe
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Joined: 23 Feb 2009
Posts: 148
Location: South Lake Tahoe, CA
Posted: Sat Mar 21, 2009 6:24 pm Post subject:
Beautiful.

I have always wanted a triple in a launch.

Some quick questions for you..

What is the:

-overall length of the connecting rods (centre to centre)

-length of just the iron rod itself

-overall height of the engine

-height of the block

-height of the colums

-length of the engine

-dimentions of the big-end (con-rod) brasses

-little-end brasses

-valve linkage brasses

I hope I am not asking too much..

I am (have been for the last 10 years) in the process of designing my own triple and rather than making all new patterns (I hate woodwork) I thought I might look into using some parts from the Elliot Bay triple (i.e. big-end brasses, connecting rods, small end brasses, etc.). That is, if Mr. Spurlock is willing to part with those pieces at a reasonable price. Also the overall dimentions of the engine will give me a ballpark figure for a manageable-size triple.

Thank you for your time.

Wesley
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steamboatjack
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Posted: Sun Mar 22, 2009 3:52 am Post subject:
overall length of the connecting rods (centre to centre) 11.625
-length of just the iron rod itself 9.875
-overall height of the engine 32
-height of the block 6.0
-height of the colums 17.437
-length of the engine 32
-dimentions of the big-end (con-rod) brasses 1.5 dia x 1.75
-little-end brasses 1.125dia x .75
valve brasses .75 dia x .375
these are the dimens as made by me, althrough I have not made the engine to the original design in some aspects as I consider it to be rather poor.
regards Jack
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87gn@tahoe
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Posted: Sun Mar 22, 2009 1:04 pm Post subject:
thanks Jack.

hmm seems the rods are shorter than my liking.

What are the oustide dimentions of the brasses (big, small, and links), and what is the finished thickness of the pistons?

Thanks,
wes
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Wesley Harcourt
-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
-'64 Buick Riviera
-'65 Buick Special WAGON
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steamboatjack
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Joined: 01 Oct 2007
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Posted: Mon Mar 23, 2009 2:48 am Post subject:
crank pin brg.
vertical height 2.312
over all width 2.85
bolt ctrs 2.125
palm width 1.25

crosshead pin brg
vertical height 1.437
over all width 2.125
bolt ctrs 1.5
palm width .75

valve brasses
vertical height 1.25
over all width 1.75
bolt ctrs 1.25
palm width .375

piston height .75 (not really enough for an engine this size but they are dished which addes strength and gives more room for the gland arrangement)
regards jack
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87gn@tahoe
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Posted: Mon Mar 23, 2009 9:42 am Post subject:
GREAT!

Thanks a TON

wes
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-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
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mcandrew1894
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Posted: Thu May 14, 2009 3:59 am Post subject:
John,


Nice looking Triple!

How are you getting around some of the valve gear issues?

Dave
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steamboatjack
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Joined: 01 Oct 2007
Posts: 39

Posted: Sun May 17, 2009 4:28 am Post subject:
Dave,

Don't get me started! the problems I have had are many and various, too much to list here, I will offer a tome to the "funnel" magazine once I have done the trials (steam trials not court trials).
I have re-designed many items and managed to juggle some of the other problems, I have all the details down on CAD now so building the second engine should be easier (yes I have a second & third set of castings)!!!
Its a pity that such a good looking engine should have so many building faults which after all could and should have been ironed out by re-visiting the drawings and patterns. Had this been done no doubt a few more would have been sold.

Suffice to say anyone hoping to build one of these would benefit by getting in touch with me.
p.s. thanks to Peter Cowie in Australia for his help also.

regards Jack




8)
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87gn@tahoe
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Posted: Wed May 20, 2009 10:27 pm Post subject:
steamboatjack wrote:
Dave,

Don't get me started! the problems I have had are many and various, too much to list here, I will offer a tome to the "funnel" magazine once I have done the trials (steam trials not court trials).
I have re-designed many items and managed to juggle some of the other problems, I have all the details down on CAD now so building the second engine should be easier (yes I have a second & third set of castings)!!!
Its a pity that such a good looking engine should have so many building faults which after all could and should have been ironed out by re-visiting the drawings and patterns. Had this been done no doubt a few more would have been sold.

Suffice to say anyone hoping to build one of these would benefit by getting in touch with me.
p.s. thanks to Peter Cowie in Australia for his help also.

regards Jack




8)


Spats Purlock does it for his interest in money, not for his interest in steam.
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-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
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Maltelec
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Joined: 23 Sep 2007
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Location: Cumbria, UK
Posted: Sun Jul 12, 2009 4:07 pm Post subject:
Good news today, the engine has run on steam:

Image
Image
Image
Image



mcandrew1894
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Posted: Sun Jul 12, 2009 10:17 pm Post subject:
Thats Awesome! Great Job!

Dave
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steamboatjack
Urchin


Joined: 01 Oct 2007
Posts: 39

Posted: Mon Jul 13, 2009 2:10 am Post subject:
Folks,
Just to state the obvious, this is very much a jury rig, I wanted to check that three years work were not in vain!, hence the bodged fire hole door, drain cocks steam pipes etc. the flywheel is the start of a rope brake being made to test the engine proper, also there are no piston rings in yet.
went better than expected!
regards jack.


8)
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mcandrew1894
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Posted: Mon Jul 13, 2009 4:28 am Post subject:
Hi Jack,

Understood.....Trust me I completely understand! I finished my engine long before I finished the boiler and it wasn't until recently I could actually test the engine at it's full design steam pressure!...I ran her first at an engine show on the steam table....with 50 psi.....not 150 psi...It was frustrating to not be able to put the screws to her on the prony brake.

Looks great Jack! What's it going into?

Dave
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Edward
Lighting the Boiler


Joined: 01 Oct 2007
Posts: 39
Location: Ambleside, Cumbria, UK
Posted: Mon Jul 13, 2009 7:22 am Post subject:
Dear Dave ,

There is a bit about what it's going into on page 1 entry 4 to this topic .
The hull in question is a Patricia hull moulded by Bossoms Boatyard on the Thames at Oxford . The original hull from which the mould was taken was made by Sam Saunders , I think in 1910, as an electric launch . It has a tunnel stern and should draw about 20"
Saunders later moved to the Isle of Wight and eventually became the Saunders of Saunders Roe aircraft manufacturers. The quadruple skin sewn mahogany construction that he patented was the pre runner of marine plywood before waterproof glues were perfected and was very strong (but a nightmare to repair when damaged) There are , I think 4 surviving sewn hulls of which probably the best known is Consuta http://www.consuta.org.uk/
I hope this answers your query and is of interest .

All the best Edward.
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mcandrew1894
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Posted: Mon Jul 13, 2009 8:41 am Post subject:
Hello Edward,

Thanks for the response, yes it does answer it completely!

At 32 feet she should go along quite nicely!

Dave
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marinesteam
Lighting the Boiler


Joined: 28 Nov 2007
Posts: 39
Location: Colorado, USA
Posted: Mon Jul 13, 2009 4:37 pm Post subject:
Wow!!!! That was a thrill.

Very nice work, can't wait to see more.

Ken
Colorado, USA
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87gn@tahoe
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Joined: 23 Feb 2009
Posts: 148
Location: South Lake Tahoe, CA
Posted: Tue Jul 14, 2009 11:08 pm Post subject:
that's great!

I bet you're all pumped to get her in the water now eh?
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Wesley Harcourt
-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
-'64 Buick Riviera
-'65 Buick Special WAGON
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Maltelec
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Joined: 23 Sep 2007
Posts: 156
Location: Cumbria, UK
Posted: Sun Oct 11, 2009 10:34 am Post subject:
Got 2 new videos of the brake test:




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Last edited by Maltelec on Mon Oct 12, 2009 2:43 pm; edited 1 time in total
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KNO3
Just Starting Out


Joined: 23 Sep 2007
Posts: 9

Posted: Sun Oct 11, 2009 12:13 pm Post subject:
Turned out great!
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DetroiTug
Warming the Engine


Joined: 19 Jul 2009
Posts: 73
Location: Outside Detroit
Posted: Sun Oct 11, 2009 2:24 pm Post subject:
Absolutely beautiful engine.

-Ron
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87gn@tahoe
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Joined: 23 Feb 2009
Posts: 148
Location: South Lake Tahoe, CA
Posted: Sun Oct 11, 2009 6:28 pm Post subject:
outstanding job!
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Wesley Harcourt
-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
-'64 Buick Riviera
-'65 Buick Special WAGON
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mcandrew1894
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Joined: 11 Oct 2007
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Posted: Sun Oct 11, 2009 6:35 pm Post subject:
Excellent! I had great fun running mine on the brake, and I am sure you did to.

She looks wonderful!

Dave
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akitene
Just Starting Out


Joined: 06 Apr 2009
Posts: 7

Posted: Mon Oct 26, 2009 4:31 pm Post subject:
Good evening,

That's a great job, indeed!

I'm very impressed by the calculated 6.4 SHP because there's no condenser fitted to the engine. In this configuration, the triple engine is in fact almost like a twin cylinder compound engine. Due to the lack of pressure drop, the LP piston is merely travelling thanks to the global momentum of the crankshaft.

With a decent condenser, the LP engine should give a few more horsepowers to the whole engine, say 9 HP or even more. How many HP is this triple engine rated?

Anyway, you've built a splendid engine.

Have fun and keep us posted.
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Edward
Lighting the Boiler


Joined: 01 Oct 2007
Posts: 39
Location: Ambleside, Cumbria, UK
Posted: Mon Oct 26, 2009 7:45 pm Post subject:
Dear Akitene ,

Your observations are correct concerning the lack of vacuum on the LP exhaust since no condenser or air pump has yet been fitted . In fact it was in some ways even worse as the LP cylinder drain was partly open and the steam supply was through a 6' uninsulated steel pipe with only 150psi at the boiler ! So we are not a little pleased with the result so far .
Ken Hall has a similar engine in his boat Oesa based in British Columbia as has Peter Cowie in Witch of Endor in Australia . Both run at 185 psi and at 375 rpm Ken reckons he is getting about 9 hp , Peter thinks he is getting about the same though I don't know if they have tested their engines on brakes .
When fitted with an insulated steam pipe , condenser and air pump and running at the boilers full pressure of 200 psi this engine could well be producing something like 10 hp .
It is a real credit to SteamboatJacks' engineering and machining skills .

Yours etc Edward
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akitene
Just Starting Out


Joined: 06 Apr 2009
Posts: 7

Posted: Tue Oct 27, 2009 2:08 am Post subject:
Good morning Maltelec,

I'm not at all surprised by the overall expected power gain when insulated pipes and condenser + pumps system are used.

What kind of air pump do you plan to use? Are you planning to use a keel condenser or a conventional one (with fresh water circulating within pipes enclosed in a vessel)?

Regards,

Akitene

Edward
Lighting the Boiler


Joined: 01 Oct 2007
Posts: 39
Location: Ambleside, Cumbria, UK
Posted: Thu Oct 29, 2009 4:10 pm Post subject:
Dear Akitene ,

The air pump has a 3 1/4" bore and 2 1/4" stroke , it will fit onto the unpainted vertical plate on the front right of the bedplate (taking the HP cylinder as the front and looking from the front) . It is in the same casting as the feed pump and will be gear driven from the crankshaft with a 3:1 reduction .

I intend using a keel condenser . I prefer them over inboard condensers in launches for the following reasons :
1) They take up less room inside the hull leaving more space for
passengers etc .
2) They are simpler in that they don't need a separate pump to
circulate the cooling water .
3)They are usually lighter .
on the debit side they add to water resistance/drag and they are more vulnerable to accident damage , grounding etc .

Initially the condenser I intend to use has 4 x 3/4" tubes 45" long giving a surface area of 424 sq" . I am pretty certain this will be too small , but it came with the hull which already has the holes made for it .
I have made a pattern for the headers of a new condenser big enough to take 3 x 2" or 4 x 1" tubes which can be installed if/when the one I already have proves inadequate .
It will be interesting to see the comparison between the two .

All the best Edward
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artemis
Just Starting Out


Joined: 24 Sep 2007
Posts: 19
Location: Portland, OR, USA
Posted: Thu Oct 29, 2009 6:12 pm Post subject: Condenser Size
My experiences -and those of others - on condenser sizing indicate a rule of thumb: for keel condensers, 1/2 sq.ft. of cooling surface per engine horsepower; for inboard shell condensers, 1 sq.ft. of cooling surface per engine horsepower. So you may be a bit undersized. On the other hand, splitting the keel condenser into 4 tubes brings a greater volume into a close proximity to the cooling surface.
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mcandrew1894
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Posted: Thu Oct 29, 2009 8:04 pm Post subject:
Hi,

Thus far,,, 1/2 square foot per bhp on a keel condensor has been too small

Going to try my new one hopefully this Saturday at 1 square foot /BHP


Will let you know.

Dave
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barts
Lighting the Boiler


Joined: 02 May 2009
Posts: 32
Location: Menlo Park, CA
Posted: Fri Oct 30, 2009 9:22 am Post subject:
Keep in mind that the water temp. affects the size of the condenser that is needed, as does the speed of the boat. In less sheltered areas here on the West Coast, the water temperatures are perhaps 55F.... but lakes and rivers are often much warmer, esp. on the surface in the summer, and hotwell temps climb accordingly.

Also, a feed water heater will help reduce the size of condenser that is needed.

Otter also likes to be moving; the keel condenser is too small when running full throttle tied to the dock (where I like to test new setups for a hour or so before casting off into the briny deeps ).

- Bart
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artemis
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Joined: 24 Sep 2007
Posts: 19
Location: Portland, OR, USA
Posted: Fri Oct 30, 2009 10:13 am Post subject: condenser size
When I moved my previous steamboat Artemis down from Puget Sound, Washington State, the keel condenser worked. Temperature of Puget Sound is 51F + or - 1F year around. On the Columbia River at Portland, Oregon I started having problems in August/September. Turned out the temperature of the river got up into the mid 70s in August/September (and down to 31/32F in the winter). Had to go to an inboard shell condenser to solve the problem
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mcandrew1894
Full Ahead


Joined: 11 Oct 2007
Posts: 149

Posted: Fri Oct 30, 2009 9:47 pm Post subject:
Hi Bart,

1 sq foot of FW heater already exists. Lake temperatures around here may be warm during the summer.

but I run in the summer.....sorry, no analytical equipement yet on board....such as thermometers...yet


Dave
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