Print

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

[MONAHAN STEAM MODELS]

It still belongs to MHB. They were developing  it for years with the plans to make a full kit out of it but decided only to make a semi kit after Peter's passing. I know Brian is really busy lately but if you ask him nicely he'll probably build you one!

[MONAHAN STEAM MODELS]

The building was taken on by a company that work on highly classified projects. The land all belonged to John's brother Ken and his widow sold the factory but not the land beyond, so although the company would prefer the steam club was not there, they cannot evict them as Ken's widow wants them there.

Well I am certainly glad to hear that the steam club can still use the lake. 

[HS93 (RIP)]

The building was taken on by a company that work on highly classified projects. The land all belonged to John's brother Ken and his widow sold the factory but not the land beyond, so although the company would prefer the steam club was not there, they cannot evict them as Ken's widow wants them there.

Peter knows more about the recent history of the club than I do, but the it's still there and I have arranged to visit on the next club day.

Peter,
        I remember John slipping in, and the stunned silence. I did not go to the evening meal, as I only live 20 minutes drive from the lake. If you had a boiler test done by the club that weekend, then I carried it out. I was the only boiler tester at the club for about 18 months, although we did have a guy in the Lake District and a couple more over in Essex.

He borrowed a spare set of clothes I kept in the car, it was so funny, I have never seen so many smiling faces all week end.I took a lot of pictures that week end IL post them separately. there where a lot of French there that weekend, so John made shore it was BEEF to wind them up at the Meal.

peter

[gondolier88]

You know, looking at that torpedo hull again- it is on VERY similar lines to 'Bat' in whats left of the WSBM- i'd love to have the hull and put Bat's machinery in- would go like bat out of hell (no pun intended!!!)

I know Hemmens did a model years ago, but not at that scale- you could have a proper Liquid Fuel boiler (gas fired of course!) and a miniature compound, maybe the ST Compound Launch- at that size and with the full beam engine casing you could make up a simpling valve arrangement.

Can just see it now...in my dreams!

Greg

[kno3]

Nick, that Mh&B is a really interesting engine. What's the reason for using 4 cylinders, as opposed to 2 larger ones for instance?
Why and when did MH&B stop making steam engines? I saw they offer now Anton engines for their boats.

[gondolier88]

4 smaller cylinders gives you higher rpm- which in a model is a useful thing.

Greg

[HS93 (RIP)]

also they are all built of standard parts so they only need one cylinder housing and they can use it and the valve gear on any of there engines they could build a 16 cylinder if they wanted.

they reason for them starting to use Anton was that they had moved to Cheddar engines and when they stopped trading they went to Anton again with there Boiler's and why did they stop well they had retired from there day job some time before MH&B started and they wanted to concentrate on new Boat kits from what I can gather.

peter

[MONAHAN STEAM MODELS]

The full sized Torpedo launch that the MHB kit was modeled after originally had a four cylinder compound engine with twin boilers. So they developed this engine for that kit.

Also everything Greg and Peter have said is correct.

When MHB was still making their engines, they were using manual, non-CNC machining equipment. There is nothing wrong with doing that at all but, this makes an already time consuming laborious job even more so. With that said, this coupled with the fact that there is really no profit in making complex steam engines after you add up all the hours and costs and subtract that from what most people are willing to pay for an engine, it starts to become understandable why it made more sense for them to purchase engines from outside manufacturers.

The same can be said for boilers. However, MHB still makes all their boilers in house. This is due to the fact that their kits require a very specialize boiler which is not available from any other manufacturer. The boilers for the MHB kits have to be a very specific weight and size. The result from this, has been MHB's development of some of the best preforming, lightest weight, quickest steaming, boilers that I have seen yet produced by any marine boiler maker. I can tell you personally as a boiler maker that the amount of additional labor that has to go into the construction of each MHB boiler far exceeds that of a similar sized boilers from other manufacturers. Regardless of the extra labor involved, MHB still offers their boilers at a reasonable cost.  

Nick

[kno3]

Thanks Nick! Which are the special features of the MH&B boilers?
I guess they must use something other than copper to save weight? I'd like to see some good photos of such a boiler, if you ave any.

[south steyne]

Hi Guys
Just looking at that beautiful engine and would like to have a go at building one similar one day hence a couple of queries.
1 I notice there seems to be no slide support for the connecting rods I don't want to sound negative as there may be a reason , also wondering how the valve rods keep contact with the cams
Cheers
John

[gondolier88]

Hi South Steyne,

I think you may be a little confused?

The connecting rods on an engine of this size don't produce anywhere near the power to warrant a crosshead slide- however the bottom cylinder cover has integral trunk guides which is enough for this engine- especially as it's a four cylinder so all the forces will act in a square around the crakshaft.

Secondly- the valves arent working off cams, they are just standard eccentrics. Many single acting engines in full size relied on cams though.

Greg

[MONAHAN STEAM MODELS]

Thanks Nick! Which are the special features of the MH&B boilers?
I guess they must use something other than copper to save weight? I'd like to see some good photos of such a boiler, if you ave any.

Hi Kno3,

The MHB boiler's main boiler wrapper or shell is made from a specific grade of nickel silver sheet which is rolled into a cylindrical barrel. The lap seam is riveted and then welded forming a very strong joint. Depending on the grade and sheet thickness or gauge of the Nickel silver, when compared to copper it is has about 1/10 the thermal conductivity and can be 2-3 times stronger at half the thickness or gauge. This allows for significant weight savings over copper and increases performance since the main boiler shell is not acting as a heat sink and sucking up all the heat generated from the burner then radiating it away regardless of insulation or lagging. The end plates and flues are still made from copper. Another feature of the MHB horizontal boilers is the return flue which allows the heat generated by the burner to remain in the boiler longer before exiting up through the stack. MHB also incorporates a super heater located in the upper return flue which also adds efficiency.

To give you a rough idea of the steam output generated by a MHB Seekadett boiler, Brian and I collaborated on a project for a client. I made a few modifications to the design of this boiler to suit the needs of this particular project we were working on, then sent the designs to Brian and he produced the boiler. This custom MHB Seekadett boiler provides more than enough steam to power the mirrored pair of Heron engines that are connected to it.   It also comes up to steam quickly. When I have a moment of free time, I will take some pictures of this boiler and post hem here.

Nick

Nick

[gondolier88]

Have you ever thought about using a 'gunboat' type boiler as a lightweight option nick?

I'm sure you know the type, but to resume- shell boiler, horizontal, firebox is a cylinder or stayed oblong in the same location as in scotch boilers, however it doesn't run all the way through, probably about 1.5 times it's width, it then has a tubeplate at the end where the tubes run through the barrel to the smokebox tubeplate, or it can be a dryback return with the tubes running back over the primary tubes and firebox to exit above the firedoor and up the funnel (or if your that side of the pond, stack )

It could be made lightweight due to it having a large heating surface and doesn't have to have a large footprint. Also space for a superheater is easily available.

Greg

[MONAHAN STEAM MODELS]

Hi Greg, 

It's funny you should mention that design. I actually built one a few years back. They're are good boilers. Currently, I am in the midst of designing and building a LIFU launch for a client. The boiler for this launch will be a scale version of a real horizontal LIFU water tube boiler.

Nick 

[kno3]

Greg, do you mean a wet-back Scotch boiler?

Nick, thanks for the answer, I'd love to see the pictures too. Can nickel silver be silver soldered to copper the usual way? Would you recommend it for a homemade boiler?

[gondolier88]

Hi Kno,

No, a wetback scotch has a full length firebox with return tubes.

Nick,

Fantastic- LIFU boilers are great- are you doing the two drum U-tubed type?

Theres quite a few in the SBA, theres a couple of the three drum types too- see my windermere steam rally thread in the other steam section, the boat I was on, 'Souvenir d' Antan' has it's original LIFU three drum, 30hp(?), with it's builders own design engine, a large compound.

Greg

[MONAHAN STEAM MODELS]

Nickel silver can be joined to copper the usual way with silver solder. There are many grades of nickel silvers available each having a specific purpose and each being a slightly different blend or composition of various other materials or metals. Some countries have different material # designations for it that differ from one country to another. So the only sure way to compare nickel silvers is to look at their composition. But there is more to it than that. With out knowing your welding, fabrication, or boiler designing skills personally, for legal reasons I am sorry but I can not recommend nickel silver for a homemade boiler. I'm sure you can understand my position. You can still do your own research. In fact when ever designing anything, it's best to do as much research as possible in order to fully understand every aspect of a design. Never take anything that has to do with safety at face value.

[MONAHAN STEAM MODELS]

Hi Greg,

For this model I was planning on doing the 3 drum type. We actually have two real full sized water tube boilers at our other shop which incorporate the U-tube style of drum. One of them is in our 46 foot Stern wheeler. The other was taken out of a steam launch and placed on a custom built cart on wheels. We use it as an auxiliary boiler for powering all the smaller engines we have. It's impressive how efficient full sized water tube boilers are, which is why I've always wanted to produce some model versions of them. I may start to offer the LIFU launch a kit with the LIFU style water tube boiler available separately.

Nick

[kno3]

Nick, I understand your position, thanks for the answer. I'll do some more research before deciding what materials to use.
My problem is that short (under 15 cm) and light boilers are not generally offered ready-made, and I need them for small boats, in the 35-50 cm range. If you know of any...

[MONAHAN STEAM MODELS]

Greg,

Here's a couple of photos of one of our water tube boilers. This is "Little Baby Steamy Pants".

Kno3,

I understand your need for a small light weight boiler. I have them designed but it will be a while longer until we can make them available.

[gondolier88]

Hi Nick,

Yes, I've been contemplating making a model sized watertube boiler myself- though i'm tending more towards a Yarrow type. However, when all said and done, there isn't much between later watertube designs, they all use roughly the same ratio of length to thickness and most had roughly trhe same water volume.

Again, if you need any help with details just ask- theres plenty of old boilers over this side!

Kno,

If you want a truly lightweight steamplant watertube really is the only way to go with a high RPM high pressure twin with engine driven feed pump and under-hull waterpickup.

Although flash steam also has it's merits, but thats a whole diffferent kettle (no pun intended!) of fish altogether!

Is it this LIFU launch that used the Victoria as the testbed for?

I thought you were building a Kingdon to go in it, or had you already built that- memory is getting worse!!

Greg

[gondolier88]

  'Little Baby Steamer Pants' is fantastic- SO american!! If that was UK it would have cast wheels and polished brass everywhere and would be someones pride and joy to be shown off, but you guys have a few beers, forget you've still got your hammer and a spanner in your back pocket and wake up with that in your garage- good job your engines aren't made like that eh!!!

Greg

[MONAHAN STEAM MODELS]

The other water tube boiler we have is in Wilhelmina our 46 foot paddle boat. Here's some photo's from an event our separate nonprofit steam organization did last year. Wilhelmina was loaded up on a truck a shipped over land from the California to New York to participate in an art show.  After Wilhelmina's arrival in New York overland by truck, she supported an enormous sculptural array installed by an artist named Swoon, the larger project's creative leader.  She steamed up and down the Hudson river.

Nick

[gondolier88]

Interested in your NFP steam org., what are the objectives of it? Well done on undertaking such a big ask, you must have got more than one young person's face to light up on seeing that.

And coal fired too...?

Greg

[MONAHAN STEAM MODELS]

Our non profit org is: http://www.kineticsteamworks.org/index.html

Here a few more pics. This is our other traction engine Hortense and our steam powered sewing machine. Don't ask!