Topic: Live steam power (Read 22696 times)

tugsmoke · « **on:** December 16, 2011, 02:52:21 pm »

Hi everyone
I am interested in building a tug from a kit such as the Mountfleet Cruiser or single screw version of the Caldercraft Imara and fitting it with live steam power plant. I intend to build the steam plant with a twin cylinder slide valve engine and obviously it is important to ensure that the steam plant is correctly matched to the model. I am looking for advice with regard to suitable engine size (bore x stroke) and matching boiler, ideally with some reference to available designs. Can anyone help?

Circlip · « **Reply #1 on:** December 16, 2011, 03:17:45 pm »

Anything less than a Stuart D10 size is going to be found wanting. Are you proposing to make your own plant?

Regards Ian.

tugsmoke · « **Reply #2 on:** December 19, 2011, 04:32:17 pm »

Hi Circlip. Thanks for your post. Yes I do intend to build the steam plant. I am new to model boats and have never built a serious steam plant so I am on a steep learning curve but I like a challenge. I have been doing some research and have found some rule of thumb formulae which purport to determine a suitable engine swept volume from the overall dimensions of the hull which I guess also relates to the model's displacement. Both the the Imara and the Cruiser come out at about 40lb. The results for the three sources used vary quite a lot but the average would suggest a swept volume in the 0.7 to 0.8 cu ins region. If I have the correct information a Stuart double 10 is 3/4 ins bore and stroke which gives a swept volume of about 1.33 cu ins. which would suggest it's a bit on the big side. I am thus somewhat confused. Of course these formulae may not be worth much and your comment may well be based on practical experience which is always the proof of the pudding so to speak. Could you please enlighten the confussed.

I am on holiday for the next week so will read you later.

Tugsmoke

Circlip · « **Reply #3 on:** December 19, 2011, 06:50:49 pm »

OK., re - building your own, check your E-Mail. Two pieces of required reading are KNH's two reference works.

Both vessels you have mentioned are tugs, which have the hydrodynamic finesse of an elephant. Had you been going for a pinnace, the plant would have been smaller due to the finer lines. There's no substitute for power.

Regards Ian.

ooyah/2 · « **Reply #4 on:** December 19, 2011, 08:40:19 pm »

Quote from: tugsmoke on December 19, 2011, 04:32:17 pm

Hi Circlip. Thanks for your post. Yes I do intend to build the steam plant. I am new to model boats and have never built a serious steam plant so I am on a steep learning curve but I like a challenge. I have been doing some research and have found some rule of thumb formulae which purport to determine a suitable engine swept volume from the overall dimensions of the hull which I guess also relates to the model's displacement. Both the the Imara and the Cruiser come out at about 40lb. The results for the three sources used vary quite a lot but the average would suggest a swept volume in the 0.7 to 0.8 cu ins region. If I have the correct information a Stuart double 10 is 3/4 ins bore and stroke which gives a swept volume of about 1.33 cu ins. which would suggest it's a bit on the big side. I am thus somewhat confused. Of course these formulae may not be worth much and your comment may well be based on practical experience which is always the proof of the pudding so to speak. Could you please enlighten the confussed. I am on holiday for the next week so will read you later.

Tugsmoke

As Ian says there is no substitute for power and a must for reference is the K.N.HARRIS books on engines and boilers for the amateur engineer.
If you are considering CRUISER or IMARA the D10 will be the engine that you will need.
At 40lbs it's a big blunt nosed boat and I hope that you are fit enough to lug it about.
I have posted details of my steam tug CERVIA which is 3/8" scale 42 " long and weighs 32 lbs, my posting shows it with a 10V engine which had more than enough power but had the old problem of stopping and starting so it now has a D10 with an engine driven pump to a 4.75" dia Scotch return flue boiler and I have to screw down the throttle valve otherwise she would drive her self under, she runs well on 30 P.S.I

( S.T. CERVIA an old Lady ooyah/2 5 802 Last post November 11, 2010, 05:47:15 PM )

this is my posting just scroll down the page.

I don't know where you got the figure of 1.33 cub" as it's nearer to .99 cub" not including a steam space top and bottom of the cylinder.

As the cylinder is 1.125" thro" the bore the swept volume is, area of the bore x length of cylinder bore 1.125" x 2 = .99 cub "

So in my opinion which ever vessel you chose the D10 is the engine to use and it's not so difficult an engine to build but a great workhorse.

I hope that this will help you.
George.

mrsgoggins · « **Reply #5 on:** December 20, 2011, 04:44:42 pm »

If the D10 is 3/4" bore and stroke the displacement, ignoring the piston rod, is 1.33cu in. The length of the bore is not relevant to this calculation.
I steam my 1/19 scale TID (45" long) with a 1/2" bore x 5/8" stroke Borderer twin (.49 cu in) piston valve engine. Cheddar claimed that one of their Puffin plants was adequate for the Imara, a bit suprising perhaps.
Just suggesting that the D10 may not be the only option.

Regards
Keith

Circlip · « **Reply #6 on:** December 20, 2011, 05:55:48 pm »

And ETW's Warrior twin. 3/4" bore x 5/8" stroke.

Regards Ian.

ooyah/2 · « **Reply #7 on:** December 20, 2011, 08:50:03 pm »

Quote from: mrsgoggins on December 20, 2011, 04:44:42 pm

If the D10 is 3/4" bore and stroke the displacement, ignoring the piston rod, is 1.33cu in. The length of the bore is not relevant to this calculation.
I steam my 1/19 scale TID (45" long) with a 1/2" bore x 5/8" stroke Borderer twin (.49 cu in) piston valve engine. Cheddar claimed that one of their Puffin plants was adequate for the Imara, a bit suprising perhaps.
Just suggesting that the D10 may not be the only option.

Regards
Keith

Keith,
You are quite correct, don't know where I was coming from but the Volume is 1.33 cub" for the D10.
I didn't mean that a D10 was the only engine but in my opinion it's the best.
I have made a Borderer piston valve engine but not using Reeves castings , I made it from stock material and made the cylinder head from a square cast iron window sash weight which was some load of rubbish.
The bore was 5/8" x 5/8" stroke and the beauty of the piston valve is the ability to reverse without all off the reverse linkage, I copied the reverse valve from the smaller Marcher engine and to prevent leakage on the piston valves I fitted Silicone "O" rings top and bottom.
I have made several D10's, with and without reversing gear and the present one in my tug is grossly over powered so 30PSI is enough.

I have seen an IMARA with the Cheddar engine and wasn't very impressed.

Keith, are you related to a Mrs M Goggins ( 93 years of age ) in Rochdale.

Ian ,
I don't like the Warrior engine as the Ali Standards more or less cover over the crank shaft and you can hardly see anything moving and it's a pig trying to get in to adjust the valve rod gland.

derekwarner · « **Reply #8 on:** December 21, 2011, 01:20:47 am »

George......is the coil in the pump discharge line a form of snubber to to take out pulsations?.....

.....I have not seen it used in model engineering.....Derek

mrsgoggins · « **Reply #9 on:** December 21, 2011, 10:14:27 am »

Hi OOYAH/2,

Thanks for the response. Nice pictures.

Out of interest, the TID was my first venture into steam and I went the route of making sure I had "adequate" power (plus a bit more) by making the full size Borderer and building a boiler to produce "adequate steam plus a bit more" (plus a bit more). I ended up with an expensive and heavy steam plant to big for my 1/20 TID. A rethink resulted in a scaled-up hull, a sleeved-down engine, a much smaller boiler and success, oh and some useful knowledge and a spare 5 1/2" return flue boiler which weighs 4kg.

My next model will still be fairly big (c.50") but I aim to keep the copper content (and cost) down starting with a relatively small engine.

I'm not surprised the Puffin/Imara did not impress you.

How did you guess, Mrs M Goggins (93) of Rochdale is my daughter.

Regards,
Keith

Circlip · « **Reply #10 on:** December 21, 2011, 11:12:08 am »

Bertinats philosophy behind the "Borderer" was a request for something a bit smaller than the D10 and the bore and stroke sizes on the plans covered various options. Would have mentioned it, but the price of castings now means a second mortgage. Bought the casting set from Reeves when the series first apppeared in ME, for less than 50 pictures of HRH. Nearly fell orft me buffet when I saw last years price.

On the scaling point, I have photos of a "Galloper" made by a first timer using Alumininininum for the straight sided bits which looked ab - fab. Galloper?? that's what I christened it, a 2X Marcher and an absolute credit to its builder.

Only mentioned Warrior to fill the gaps George, strangely, Reeves quote both Borderer and Warrior as "Stationery" engines? Has the TID got a narrower waist than the other two?

Regards Ian.

steamboatmodel · « **Reply #11 on:** December 21, 2011, 02:02:01 pm »

Quote from: mrsgoggins on December 21, 2011, 10:14:27 am

How did you guess, Mrs M Goggins (93) of Rochdale is my daughter.
Regards,
Keith

But your profile lists you as 67 years old.
Regards,
Gerald.

mrsgoggins · « **Reply #12 on:** December 21, 2011, 02:32:20 pm »

Gerald,
B****r, guess my credibility rating has gone down.

Keith

mrsgoggins · « **Reply #13 on:** December 21, 2011, 02:34:55 pm »

For info,
My 1/19 TID is 45" long x 11.5" beam, about the same as the Imara I think but probably a bit lighter at about 38lb.

Regards,
Keith

ooyah/2 · « **Reply #14 on:** December 21, 2011, 06:05:38 pm »

Quote from: derekwarner_decoy on December 21, 2011, 01:20:47 am

George......is the coil in the pump discharge line a form of snubber to to take out pulsations?..... .....I have not seen it used in model engineering.....Derek

Derek
It is simply a long length of 5/32 " copper pipe rolled up to keep it tidy, at the time of building this engine I didn't have a test boiler so a feed had to be taken from my steam tug, hence the length.
Air vessels on toy steam engines are not required they may look the part but don't work.
I built a Single cylinder double acting engine using a Stuart 2.25" bore x 2" stroke cylinder casting and couldn't get an air vessel to work, the engine was powered by a Yarrow boiler that I made.

Keith,
I suspected that she might have been your Grand Daughter so maybe you should be called Methusela, any way I shall be in Rochdale over the Christmas holiday for 4 nights so I shall ask the dear old lady if she knows any Goggins in Oldham.

Ian,

Just had a look at Reeves Cat and the castings for the Borderer are quoted as £156 which is much cheaper than Stuarts D10 but Stuarts package includes all of the materials required to build the D10 so it may not be so attractive.

May I wish you all a happy and joyful Christmas.

George.

Circlip · « **Reply #15 on:** December 21, 2011, 07:47:41 pm »

Not sure if it still applies but the Borderer castings were all gunmetal.

And a happy Hogmanay to you George.

Regards Ian.

mrsgoggins · « **Reply #16 on:** December 22, 2011, 10:08:33 am »

It should not be too difficult to fabricate the main Borderer castings from bits of plate and bar, saving some weight as well as cost.
Interesting to compare the size of my 1/2" x 5/8" Borderer with the diminutive TRV1A of the same capacity - it offers some ideas on how an engine can be built without castings.
Keith

derekwarner · « **Reply #17 on:** December 22, 2011, 11:08:24 am »

Hullo & thanks George ....when you say......."Air vessels on toy steam engines are not required they may look the part but don't work" ....is it that we cannot accurately measure or monitor pulsation & any dampening effect at our low pressures of say......3.5 Bar with our model pressure gauge systems?

as in theory they [any fixed gas accumulator] must have a dampening effect.............

Our member Bernhard........builder of open hull steam vessels has installed a form of accumulator in a number of his steam vessels.........possibly he may offer comment here

regards Derek

Circlip · « **Reply #18 on:** December 22, 2011, 11:36:26 am »

Quote

Insert Quote

It should not be too difficult to fabricate the main Borderer castings from bits of plate and bar, saving some weight as well as cost

It's always difficult trying to advise the "What, How Why" questions as the modellers ability to "Build" is not usually given. An age thing usually predetermines that our generation threw Nowt away and passing a scrap heap (PRE Skip days) without winning a prize was unheard of.

The "Flexible friend" has changed the hobby entirely, as now, if you can't order one day and be on the pond the next, causes withdrawal symptoms in many and "Building" seems to be a dying art.

Regards Ian.

ooyah/2 · « **Reply #19 on:** December 22, 2011, 03:49:50 pm »

Quote from: derekwarner_decoy on December 22, 2011, 11:08:24 am

Hullo & thanks George ....when you say......."Air vessels on toy steam engines are not required they may look the part but don't work" ....is it that we cannot accurately measure or monitor pulsation & any dampening effect at our low pressures of say......3.5 Bar with our model pressure gauge systems? as in theory they [any fixed gas accumulator] must have a dampening effect.............

Our member Bernhard........builder of open hull steam vessels has installed a form of accumulator in a number of his steam vessels.........possibly he may offer comment here

regards Derek

Hi Derek

If you can't accurately measure the dampening effect in such low pressures an air vessel it's not required.
Our friend Bernard as far as I can see builds superb model boats but I can't see any sign of engine and boiler builds.
One thing I am not and that is a model boat builder but have built many engines and boilers of all sizes including high pressure Flash steam plants and I assure you that air vessels on the delivery side of our small model pumps are not required and it didn't work on the larger engine that I posted a pic off.

Keith,

I must say that those little TVR engines are very well made and priced, being C.N.C. made , Graham can churn them out very quickly.
I had to do a repair on one once for a friend, the flanges on the manifold to the cylinder were leaking steam and he had messed about with the timing.
The timing was sorted quickly but my heart was in my mouth with the brass screws into the Ali cylinder block which by memory was 10 ba.
I was terrified that I would either drop the screw or strip the thread into the cylinder head, otherwise great little engines.

Ian,
One of the biggest problem in scratch building is buying small quantities of brass and steel, I have found that suppliers in Glasgow are not keen on cutting , say a 6" length of 1" round bright steel but quite willing to sell a 3 m length.
This is why I save up and put an order into Blackgates for stock material and collect when I visit Rochdale.
When I was in business and moving amongst engineering works I was able to pic up scrap lengths of materials , but alas no more,

George.

kiwimodeller · « **Reply #20 on:** December 23, 2011, 09:31:49 am »

Not sure if it is O K to put it on here or whether I should call myself a "trader" and put it in the Sales section but I did email Tugsmoke with some pictures of some New Zealand made engine kits so I guess it is relevant to this thread. As has been stated it is difficult to purchase small quantities of materials to build just one engine so these kits have been put together with all the neccessary materials including fasteners and a comprehensive set of drawings and instructions. I will add a couple of photos (I hope!) but if not have a look in the Traders section on Paddleducks http://www.paddleducks.co.uk/smf/index.php?topic=4885.0 The V Twin is 16mm by 16mm and the inline twin 20mm by 20mm. There are also single cylinder and Walking Beam kits available. The gentleman who makes them does not market them on the net but many have been built in this country, mostly through model engineers clubs. A lathe is essential and a mill or milling attachment a help to do all the maching but it is easy if the builder follows the instructions carefully. If anyone wants to know more send me an email or PM. Cheers, Ian.

frazer heslop · « **Reply #21 on:** December 23, 2011, 11:12:35 am »

Hi,if you are looking to buy small lengths of material try m-machine they will sell by the inch but obviously the postage is a killer
Best wishes frazer

ooyah/2 · « **Reply #22 on:** December 23, 2011, 11:57:35 am »

Hi Frazer,
Thank's for the info, I use Blackgates as they will cut to my requirements and their postage will be the same .
I have used Blackgates for years and find them very helpful, I have the added advantage that I visit my family in Rochdale and if I make up an order I can collect when I visit, or my son when he comes up here can bring materials with him, saves postage. Happy Christmas.
George.

tugsmoke · « **Reply #23 on:** January 03, 2012, 04:59:18 pm »

Hi everyone

I have been on holiday which unfortunately included a unscheduled visit to a hospital in Tenerif so I have only just read all the posts on this thread I started. Thanks to everyone for their replies.

Ian (ciclip)
Thanks for the KNH references, I have obtained these but have not had time to read and digest them yet.

George (ooyah)
You say your your 32lb Cervia went OK on a Stuart V10 which is a 3/4 bore x 3/4 stroke single cylinder which is swept volume of 0.62 cubic ins. this suggests that the mentioned calculation of 0.7 to 0.8 cubic inches is about right for the Imara.

Keith (mrsgoggins)
Your 45 ins TID runs OK on a 1/2 ins bore x 5/8 ins stroke borderer. Thanks for that.

Well at the moment the bottom line from these comments seems to be that Borderer is about the right choice, with the decission about 1/2 inch or 5/8 inch bore to be deferred for the moment. I think the drawings are available from My Hobbystore. I understand that Model Engineer ran a series of articles on the construction of this engine I will have to check if these are still available - unless someone out there could help. I also would not pay £150 for a set of castings containing £5 worth of material. I will use stock bar etc. unless someone has some much cheaper castings.

Anyone like to comment on the Borderer option?

ooyah/2 · « **Reply #24 on:** January 04, 2012, 11:23:21 am »

George (ooyah)
You say your your 32lb Cervia went OK on a Stuart V10 which is a 3/4 bore x 3/4 stroke single cylinder which is swept volume of 0.62 cubic ins. this suggests that the mentioned calculation of 0.7 to 0.8 cubic inches is about right for the Imara.

Hi .
I have a copy of the article which was published in Model Engineer for the Borderer engine , article started on 1-12-89 to 7-12-90. ( 28 pages. )
These are photo copies taken from the Mag and are very readable,
If you wish P.M. your address I will post them to you if you will photo copy them and return my originals to me. ( don't put your address on the open Forum )

My Cervia with the 10V had ample power but being single cylinder it wasn't reliable in stopping and starting with the reverser that was made , hence it is now engined with a D10 complete with Stevenson link reverse. ( pics available on R&D S.T. Cervia an old lady )

The drawings for the Borderer are still available but from your statement that you don't wish to buy the castings this article has all the dimensions that you will need to scratch build from stock material.

In my opinion you should make the engine as per Bertinants drawings 5/8" x 5/8" as you will have the power on hand but don't have to use it all.

My preference of boats would be Cruiser as most of the rigging is fitted to the superstructure and gives quick and easy access to the steam plant.

Then I am biased as I used to see Cruiser on the Clyde when she was owned by Bennies.

Sorry to hear that your holiday was spoiled by a hospital visit, hope you are now well.

George

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Author Topic: Live steam power (Read 22696 times)

tugsmoke

tugsmoke

ooyah/2

ooyah/2

steamboatmodel

ooyah/2

ooyah/2

frazer heslop

ooyah/2

tugsmoke

ooyah/2