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I am sure Tony will be able to find 20 shillings and sixpence considering his previous employment...... Barry.

"Benton & Stone, Bracebridge Street (ENOTS), by 1926 also at Aston Brook Street, art metal workers and makers of gas fittings, garden syringes and sprays and motor accessories. Trade Mark 'ENOTS'. " Bracebridge Street, Birmingham is better known for the home of Norton works motor cycle racing team. Certainly an address to have. Barry.

...and this is the Enots fuel filter in real life. As one who has searched for one for the past 15 years I think it might be a case of another trip to the foundry to have the top bracket and body cast. Put me down for two please! Barry.

If you don't have your Meccano ( or Trix ) to hand to visualise the motion of coupling shaft with two universal joints, here are some pictures which demonstrate the non-linearity of the motion. All the pictures show the input and output shafts in synchronism which mean they are running at constant speed. The first and second pictures show an angle lead and then an angle lag of the coupling shaft. This relates to the coupling shaft running fast and then running slow. The last three pictures show how the angle (speed) change is greater with a larger mis-alignment of the shafts. Barry.

It is strange that the 'box joints that Steve has just referred too were used on fire engines but not on his subsidy lorry. Here are the essentials of a box joint The bronze 'slippers' wear or in the worst case the actual box splits apart. Making sure that they are full of graphite grease before any journey ensures a longer life. Jezebel the RCS Dennis 'N' Type has had a fair share of box joint trouble but this probably because it is driven by students who have yet to hone their mechanical empathy. (Steve, didn't you use to drive Jezebel....?) By the end of the 20's where the 'T' headed White and Poppe engines were being phased out and unit construction was being introduced the box joints had gone too, to be replaced by a flexible cotton disk coupling. The last picture shows this type of coupling on my 1930 Dennis Low Load fire engine. Barry. This last picture also shows the 'drip tray' which is fitted to early Dennis Fire Engines. It runs from the flyweel to the back of the gearbox. It means that all the oil seals and couplings can dribble oil or spray grease without leaving it all over appliance room floor in the fire station.

Steve, Have you ever seen a Dennis spanner for tightening up this type of gland nut? I have never seen one, although it does seem a bit rudimentary if the expectation is to tap it round with a hammer and a screwdriver.

You are a funny bunch! So much time is spent making equisite parts, faithful replicas of the orignals and then you go and use black 'goo' to seal it altogether! I must admit that I missed the tell tale black bead in one of the earlier photographs. Barry.

I did not see a gasket go in place during assembly? Should there have been one? I have lost count of how many Dennis diff's you have had so I am sure you must know! Best wishes, Barry.

....and as I asked the question about pump size....I knew in the back of my mind that I already knew the answer. It is a Steve guessed, related to pump speed. On my engine and similar engines the pump runs at crank speed whilst on Steve's engine it is at camshaft speed. Barry.

Something which has just crossed my mind is the size of this water pump. On the later developments of this engine and indeed on the larger 60HP White and Poppe engine the water pump is so much smaller (See picture below). Can anyone offer any explanation? Barry.

I like the way how Steve has drilled the flange holes. No rotary table was used here, just an old fashioned set of dividers. Barry.

Tony, do you have a tool post grinder attachment to give a good surface finish to pins like these? Will Steve have the pins to make sure that they are a 'good fit' in the blocks or can you rely on dimensional accuracy alone? Barry.

Looking a little harder, it quite posssibly seems that my efforts at making replacement 'Grover' washers has been misplaced. An Indian washer making company seem to have them in all sizes. I have asked for a quotation. Barry.

Steve, on all my Dennis's up to the mid 30's the washer style which was used throughout was a thick spring washer with a central concave groove. They are stamped 'Grovers Pat." and are certainly the ones which were used on the silencer. Quite possibly these are more scarce than your Thackeray washers. The only advantage with the Grover washers are they can be made relatively simply. Barry.

On this type of silencer the central perforated tube has a 'bung' in the middle. The exhaust gas and noise escapes from the input set of holes, rattles around the can and then passes through the exit set of perforations out to the tail pipe. However, Tony should have gone to Kwik-Fit who have Dennis Subsidy lorry slencers on the shelf - see picture.

Did anyone notice the anticipated precision of the assembly operation? PRE-DRILLED split pin holes before the nut has turned on the thread!.....or has there been a lit bit of sub-assembly beforehand to make sure the holes are in the correct place? If you look at the drawing you could almost imagine that the holes should be a little closer to the end of the stud.

As the topic of hose clips is 'gripping' the discussion at the moment I thought I would add my solution. As Steve has just pointed out there are various commercial equivalents to the clips that he has made. Two examples from 'Vintage Car Parts' are shown below. The text which accompanies them; "Nesthill brass hose clip with brass toggle tightening tail. authentic style under bonnet detail on pre war vehicles. made to suit specific outside diameter of hose, minimum size that we offer is 20mm, maximum size that we can offer is 100mm diameter. accurate measured outer diameter of hose is essential to what it will close up to. these clips are not designed to be adjustable for a 'size range' but are made to a specific and particular size. clip is 14.25mm wide." hints to one of the problems with this type of clip in that they are not very adjustable and in practice cannot apply much clamping force before the brass ears start to bend. In the real world I have found that my cast water pipes are not that round and I only have metric hose to hand which is a bit too much of a loose fit for comfort. So a quick solution without having to resort to a Jubilee clip is a low cost stainless clip sold on ebay for turbo hose plumbing on 'custom' cars. They have tremendous clamping power and by replacing the ordinary nut with a Number 3 brass wing nut adds 'period charm'. Certainly better than a Jubilee clip!

On proper Dennis's (Yes, Fire Engines!) the short coupling shaft is replaced by a PTO which drives the fire pump. As you can see from the drawing below, Dennis distributed all the 'heavy lumps' throughout the length of the chassis. Performance car makers today call this a 'low polar moment of inertia' essential for going round corners at high speeds. Just the attributes needed for a fire engine but maybe not so essential for a WW1 truck! Barry.

Tony, a lovely finish on the outside of the steel tubes - it is a shame to paint them green! Do you have a photograph of the end of the shaft so we can all see how the coupling works? Barry.

Although this looks trivial, the interesting bit has been missed out from the photographs - the cutting of the thread. Were they screw cut on the lathe followed by a die, or a die only? If a die only, what is your technique for keeping it square to the job? (and I hope the copper washers under the plugs will come along later....) Barry.

Tony, I see that you are going to make the water pump spindle in stainless steel. Any particular reason why? The original was almost certainly mild steel, all mine are. A quick look at Wikipedia shows that the first patents for Stainless Steel were only appearing in 1915. Was the clutch centre turned on a manual or a CNC machine? I know that the shaft oil groove spiral is a particularly difficult thing to cut in neatly on a manual machine as I have tried it. Barry.

In my little foundry book, chaplets are referred to as any object used to stop the core from floating. The book suggests the use of flat headed nails. This drawing repeated from 'Foundry work for the amateur' shows all. Barry.

If you want to follow Steve and develop your pattern making skills and learn more about foundry work then this book is excellent. Barry.

Norman, you couldn't really tell from that screen shot but the flange is angled to the main bore - see below. The model wasn't meant to be a perfect representation but just something to visualise how things might go, but we don't mind you being 'picky'! Gordon, yes cheating is easy. I imagine you mean something like this without any 'ears' on the flange. But to have the ears, having an external core part for the flange seems the only positive and repeatable way of producing the part. We will just have to wait for Steve to give a full description of how it is done.... Barry.

With the pace of this restoration it is easy to skip past parts of it where really we should stop and marvel. I am still stuck at the pump elbow! I have been trying to pull the pattern out of the sand for the past few days without any success. Even using solid modelling does not make it much easier to visualise. In fact just drawing the part is difficult - far easier to use a block of wood, some filler and some basic hand tools.... Barry.