Well, as we reach March 2024, I should jot down some notes on the work being undertaken this winter.
Work done
We made a list of jobs to be done back when we fetched Befur out last autumn. The completed work is shown below in Green, still to be done in Red:
Cleaning the inside of the boiler, removing oil t0 improve efficiency (reduce fuel consumption) –Done – notes and video here
Cleaning the inside of the condenser, for same reasons and improve vacuum – Done – notes with Boiler Work above.
Remachining the LP crosshead and glands as it is now clear that this is the principal source of the hateful knocking the engine makes. – LP Done – see below
Replacing the pump drive worm box, as this is at the point of failure, and adding “assistance springs” to reduce the torque requirements on this box, to extend its probable life! (probably another post here too). – See below
Replumbing the condenser to be “contraflow” as this should improve it’s efficiency too.
Attempting to design and fit a clutch to the prop drive to allow it to freewheel when sailing.
Attention to paint and varnish
Possibly fitting a reinforcing inner fore-deck and removing the anchor chocks and resealing to improve weatherproofing.
Well as I sit here in my new (Christmas present) noise cancelling headphones that are doing a fine job of isolating me from the culinary marathon taking place in the kitchen, it seems a good time to provide an update on Winter ’23/’24 boat work list!
We have an extensive set of work, aiming to both address some mechanical and wood-related failures and hopefully upgrade Befur’s performance for 2024.
You might remember from the “year end review” we had a provisional list of work to do, and some of it we have done!!!! So below you will see the worklist together with notes on progress and on other jobs that made their way into the list.
Cleaning the inside of the boiler, removing oil to improve efficiency (reduce fuel consumption), and prevent overheating resulting from the insulation effects of oil-in-tubes.
Inside tube bank, after brushing off the years’ soot – looking good!
Inside tube bank before brushing – not bad for a years’ soot! Liquid fueling rules!
Boiler with cladding/casing off – after a quick brush to remove soot.
Weighing the Boiler – 174Kg dry
A Spanner for Economiser and Superheater Headers
Cleaning the inside of the condenser, for same reasons and to improve vacuum.
Well both of these activities have been concluded, as well as the first part of the annual boiler (a hydraulic test at 375psi). It was nice to see how little soot had accumulated in the years’ steaming – another advantage of liquid fueling.
The boiler was good and tight, holding it’s pressure for many minutes without pumping.
We had concluded that a less-than-perfect hotwell design had allowed some oil to make it into the boiler, so it seemed a good time to try to do a good job of cleaning it. The advice was to fill it with a mixture of detergent and TSP (trisodium phosphate), and then heat and circulate. The instructions for power station boilers suggest 48hrs will do, but I opted for a lot less!
We decided to do the condenser at the same time, and use the boiler to heat itself.
The video shows the process half way through. We left the boiler full to cool naturally, and then pumped the fluide round again, and this time we did collect some oil on the oil collecting cloths in the hot well. We then drained it down and repeated the process. Bringing the boiler to a boil and holding that temperature for an hour or two.
At the end I felt we had made some progress, and the oily “scum” in the sight glass was gone, and a considerable amount of oil was removed from the condenser – I think the latter is going to be a recurring problem as it resides between the engine and hotwell, ….
We also took the time to weigh the boiler (174Kg without the wooden cladding, and dry) – thus demonstrating another positive attribute of water-tube boilers, as a VFT102 Vertical Fire Tube boiler with half the heating surface of the John King Yarrow (17sq ft v 32 sq ft) weighs in at 300Kg!!!.
Befur’s “Yarrow” water tube boiler.
At this point I should add a promotional plug for SBA Services Limited (the trading arm of the SBA).
They offer a wide range of services (like boiler testing and boiler designs, and castings and engine designs) for steamboaters (both SBA members and others)), and publish the design of Boiler which I built for Befur (which did not need any welding, so is a home workshop proposition).
A Spanner for Economiser and Superheater Headers
While we were doing this, I made a “spanner” to hold the headers of the Economiser or Superheater, which can tend to twist their respective tubes when attaching fittings etc.
We also tied some parts of the internal insulating board to the outer casing, which had slipped in service.
Lastly we made a new handpump. This is just a larger version of the one in Befur now, to reduce the number of strokes needed to fill or refill the boiler, this again was built using a casting from SBA Services. This is to a design by Ian Cross with drawings supplied with the casting prepared by John Maltby.
I decided to make this with an o-ring seal instead of a gland and stuffing box. An easy build, drilled to about 24 mm diameter, and then bored (with newly made boring tool) to 25mm. There are some pictures of this below. I forgot to video the final boring 😦
4-facet drill sharpened on the Quorn cutter grinder..
The Old Handpump
The New Handpump – with 25mm ram
New Hand Pump casting being squared up on shaper
Hand Pump under construction
Pattern and two castings for SBAS Handpump
Two 3D-printed patterns for a horn for the Siren
So, needing a post-xmas-lunch nap, I will hold over the rest of the rebuild story to the next post.
I will just mention that we (Paul Self and I) are planning to do some backyard foundry work to make a trumpet for Befur’s new siren. John Knapton (another of the Windermere mafia) has kindly 3D printed some fabulous casting patterns, which we will attempt to cast in bronze/brass in the next few weeks….(thank you John)….
<for next time>
Remachining the LP crosshead and glands as it is now clear that this is the principal source of the hateful knocking the engine makes.
Replacing the pump drive worm box, as this is at the point of failure, and adding “assistance springs” to reduce the torque requirements on this box, to extend its probable life! (probably another post here too).
Replumbing the condenser to be “contraflow” as this should improve it’s efficiency too.
Attempting to design and fit a clutch to the prop drive to allow it to freewheel when sailing.
Attention to paint and varnish
Possibly fitting a reinforcing inner fore-deck and removing the anchor chocks and resealing to improve weatherproofing.
Well, as mentioned elsewhere I have found it very hard to make a whistle that sounds nice (in fact one that sounds at all!) … the principal is simple enough, but the practice is much harder with quite fine tolerances and dimensional “magic numbers”.
Making a nicer whistle – version #4 (at least)
I had one noticeable success with a three-chime whistle for the 5″gaugeloco, and the one for the Windermere Kettle is pleasant, but the main whistles for the boat just screech (very loudly, or not at all).
We need a Siren!
This idea has cropped up several times, but finding a set of drawings was hard, and with the “whistle experience” in mind, I really wanted a “guaranteed” design.
Well, as is often the case, the SBA provided an answer via their house magazine Funnel, with an article from 2007 (Issue 112) by Peter Cowie from Auz. This provided the basic idea and design for Befur’s Siren, which I can guarantee works! (Other boaters classify it as “deafening” even from many metres away!)
It does take a fair quantity of steam to set it off, on Befur it’s plumbed in via a 1/4″BSP ball valve and at 200psi that works very well. Here’s a video of it running on air (quietly!)
You should be able to download this article from the link above. I found the drawings provided hard to decipher, so with the drawings in this post and the pictures perhaps all will become clear. You will notice that mine is less shiny, and still awaiting a “trumpet”, there is talk of casting some in bronze!
Drawings
Pete’s original drawing from the Funnel Article
As I noted above the drawings in Funnel are quite hard to interpret (I think there were probably more sheets, which would have made it clear.
However, I decided the simplest approach was to re-draw in viaCAD, so there are links below to a viaCAD file and exported version in .dwg (Autocad file), and .png (graphics picture) file too…
(If you have trouble downloading the drawing files (WordPress doesn’t like them) then just message me (at foot of this post) with your email address and I will send them to you)
These drawings are metric (apart from the threads that are either BSP or TPI threads (because I happened to have the imperial change-wheels fitted to the lathe at the time!!)). The drawings show the components, a sectional GA , listing of the stock materials used to make the siren and a drawing of how the distribution plate was originally drawn (but not how I made it!).
Perhaps the key bit of understanding (which took me a while to spot) was that there is a steam space between the Porting Cylinder and the Body, which is supplied through the spaces in the Distribution Plate and delivers steam to the ports in the Porting Cylinder.
Manufacture
The material for the siren (from M-Machine metals in Darlington and on-line)
The siren is built from phosphor-bronze cored bar, all sourced from M-machine Metals in Darlington.
M-machine will take phone orders and are happy to supply small quantities for home-workshop user. The picture shows the stock used to make the siren, at a total cost of about £75. (in 2023)…
These are stock-sized cored-bar from their catalogue, and the sizes purchased are shown in the drawings I prepared.
The majority of the manufacture is simple lathe work. The larger threads are all screw-cut on the lathe. I usually cut the internal threads first, then cut the male (outside) thread, using the other part as a gauge.
The most challenging parts of the build are the Porting Cylinder and the Rotor.
Rotor
Siren porting cylinder and rotor assembled in the cap.
The Rotor slots are just slots cut vertically (radially) into the rotor with a slot drill, while the rotor is held in a rotary table on the milling machine.
The slots in the rotor can be seen in the photo on the right, inside the porting cylinder.
There are eight (8) evenly placed slots in the rotor.
The REALLY important factor for the rotor to work effectively is its fit within the Porting Cylinder, which needs to be quite loose. The bore clearance needs to be at about 5 thousands of an inch (sorry for mixed units!), and it’s axial clearance when the Porting Cylinder is clamped within the Cap is again about 5-thou. Clearances any tighter than these numbers will mean that the siren will not start, as the starting torque is quite limited, and any contamination or particles in the steam will jam it in place.
Porting Cylinder
The Porting Cylinder is, without doubt, the most complex component. It houses the rotor, with a retaining lip at the lower end, and the rotor is located by the cap at the top. The Porting Cylinder is held in place by the Distribution Plate below it, as the Cap is screwed down tight on top.
The porting cylinder has two sorts of slots/holes machined into it. The long slots (4 off) probably provide most of the sound. They are machined tangentially into the Porting Cylinder, this is so that the steam passing through these ports causes the rotor to spin and produce the siren sound, as the steam is released and cut off.
As it is possible that the Rotor stops with the above 4 slots covered, and thus no steam would flow to start the Rotor spinning. For this reason 10 “starting ports” (holes) are also machined into the Porting Cylinder walls. These are also tangential, and “ensure” that some steam flows to start the Rotor.
A good view of the tangential starting ports/holes and slots in the Porting Cylinder – note three starting ports between these two slots.
A spreadsheet showing the angular positions of the 4 slots and 10 ports in the Porting Cylinder
The Porting Cylinder is machined by holding it in a rotary table on the milling machine, while the ports and slots are machined by plunging a slot drill into the walls of the Porting Cylinder.
The location of the ports (10 off) and slots (4 off) are dimensioned on the drawings, but the angular positions are shown in the adjacent table. My maths was not good enough to produce a symmetric and even spacing, but actually I think the asymmetric spacing probably adds to the sound quality!
Tangential Positioning
The tangential billing is achieved by off-setting the centre-line of the Porting Cylinder from the centre-line of the drill, by 19.8mm. These dimensions can be seen on the drawings.
Final Observations
It is a very satisfying object to make and to use – even drawing admiring comments from other berth-owners at Befur’s marina. It is VERY loud, so some restraint is needed to avoid becoming a nuisance. Feeding it via a ball valve allows the siren to be played very effectively, from low growl to deafening howl. – who knows, maybe if we complete the Trumpet it will be louder yet!
It does generate a deal of condensate, so aim the outlet away from the the passengers, to avoid giving them an impromptu hot shower.
I’ll probably continue trying to make the perfect steam whistle, but for now we are happy!
Picture Gallery of Components
Porting Cylinder and Rotor installed in the Cap.
Three starting ports and two “sound” slots in the Porting Cylinder. You can see the edge of one of the rotor slots at the bottom of the sound slot at the right.
Siren porting cylinder and rotor assembled in the cap.
Cap and Elbow
Cap showing threads
A set of partially complete components
A good view of the tangential starting ports/holes and slots in the Porting Cylinder – note three starting ports between these two slots.
Well we had quite a good year, but a rather wet summer and too much playing with old motorcycles meant that Befur saw a lot less sailing and steaming than planned… but she performed pretty well.
The pictures below provides a summary of some of the activities we undertook.
Projects
During the year we undertook a couple of projects, firstly to make a better whistle, and when that failed making a siren for Befur (and that’s the subject of another post). and some maintaining things, (remaking the auxiliaries manifold, hunting for vacuum leaks) still that search for vacuum and silence!
Winter Work
In overview we are planning to do the following things in the next weeks:
Cleaning the inside of the boiler, removing oil t0 improve efficiency (reduce fuel consumption)
Cleaning the inside of the condenser, for same reasons and improve vacuum.
Remachining the LP crosshead and glands as it is now clear that this is the principal source of the hateful knocking the engine makes.
Replacing the pump drive worm box, as this is at the point of failure, and adding “assistance springs” to reduce the torque requirements on this box, to extend its probable life! (probably another post here too).
Replumbing the condenser to be “contraflow” as this should improve it’s efficiency too.
Attempting to design and fit a clutch to the prop drive to allow it to freewheel when sailing.
Attention to paint and varnish
Possibly fitting a reinforcing inner fore-deck and removing the anchor chocks and resealing to improve weatherproofing.
Wow, that looks like a lot of work when you write it all down!!!
A pictorial review of 2023
Hover over image to see caption, or click image to access full size versions.
Famous at last – front cover of the 2023 Windermere SBA Layup Supper.
Hauled out and in the Lane’s barn ready for some winter work
Making a nicer whistle – version #4 (at least)
A set of partially complete components
Swans bring new Signets to introduce them to Befur (the bread & cake boat)
They are getting the hang of it!
Steaming with friends – Russel & Maurine on Obsidian
The Maltbies – a day out with Grayling
Steaming with Shamrock – a nice steam down the lake
A new boat in the fleet: John Knapton with Anachronism!
The Skipper in the sunshine!
Back in Heggerscale – ready to be washed and ready for Winter work
Back at Heggerscale, waiting for a wash and some maintenance
Finding a new Generation of Steamboaters – “Keeping your feet dry” at Fell Foot
The KYFD class of ’23
Wasting boating time on old british bikes and sidecars!
Well, I guess that’s what progress looks like – I haven’t written a thing since we re-launched in May, so it’s actually been going rather well! But a tentative phone call from friends in Australia to discover if Befur’s lack of posting indicated we were no longer shuffling along this mortal coil suggested it was time to write something!…. But, all is well, Lou, I and Befur are in good fettle….
As a last post on the subject of correcting the valve timing on the Leak Compound in Befur (prior to “sea trials” later in the year), here we will look at the results from the static (blowing) valve timing tests, and compare to the results prior to rebuild. But first a video of it running on air with the new timing…
I just updated this post to improve the pictures and ordering to allow simpler comparisons between old and new timing data.
This time we are looking at how to fix the problems with the Leak’s valve gear design. This is now part of our Leak Hints and Tips section on the known errors or problems with Leak design……
As we get to the end of January 2022, the tuning/rebuild/shopping of Befur’s engine continues, once this is complete we can get on with the list of hull and fittings-related work. But it seems we should at least explain what work the last few months have contained…
SY Befur 