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Steve, own up! You build DENNIS dust carts for a living!

Tony, Thank you for the explanation of the wood. I am afraid that the photographs had me completely fooled. With regard to polishing the trickier parts of the wheel, have you tried abrasive grit coated polishing mops in an electric drill. Abrasive grit compound is what the professional casting polishers use. You can buy it from the Frost people. www.frost.co.uk This is what they say in their catalogue; Using our combination kit, you can start with a rough casting and end with a mirror finish. Everything needed is included, except you and the drill. Kit contains 24 pieces and instructions. Pre-polish and finish Aluminum Alloys, Brass, Copper, Steel, Iron and Stainless Steel! Grades Available There are several grades of abrasive compound available. The lower the grit number, the coarser the abrasive and the faster metal removal (giving a poorer finish). The higher the grit number, the finer the abrasive and the slower the metal removal but it provides a better finish. To take a metal from a poor condition to a finish ready to be polished, will take several greaseless compound processes: for example you can start at a wheel coated with 120 grit greaseless, next 180 grit and finally the wheel coated with 240 grit. It works really well just like the Power File..... Barry.

Tony, Can you explain the 3 ply construction of your main body planks? I know how much work has gone into your wheel, but what has crossed my mind is whether a super fine finish is really required on the areas which are to be coated. Quite possibly the 'plastic' coating will hide a lot of minor imperfections. Incidentally all Dennis fire engine steering wheels also had the spokes coated too. Barry.

"when with an almighty bang and a flash, the Power File gave up!" I feel rather guilty for recommending the B and D Power File to Tony now. However I have only had 2 in twenty years with my last one now being 5 years old. Just unlucky perhaps. I am sure the Dynabrade Power File will be more robust but it is around 8 times the cost at anywhere between £250 and £350 on ebay! Barry.

Trish just remarked that it was maybe better that Steve gave up welding and took up gardening, the latter seeming to need some attention too! However if you were going to consider a new welding set, then you would have to look at the DC/AC TIG inverter sets that you can now buy. You can still stick weld with them, but the TIG mode can turn you into an artist. For our hobby they cannot be beaten. Barry.

Anyone who left their shed/workshop early last night might have seen a rather stirring sight on the ITV drama 'Downton Abbey'. For half way through, bringing a lorry load of trouble makers, was an early Dennis lorry! Barry. (If you go to the ITV video player, it occurs just after 27 minutes of the Sunday 31st October episode).

This step looks far too good to paint! Could they have been chemically blacked originally as painting doesn't seem appropriate?

As Steve mentioned earlier wire cutting tapers is relatively easy. For normal parts with parallel sides the wire feed and exit tubes are co-axial so that the wire is held vertically. If the feed tube is displaced to one side the cut is tapered. In practice both the feed tube and exit tube can move completely independently of each other. This means that taper cuts of 30 degrees or more can be achieved. Clever software manages the positioning as the wire cuts arcs with tapers. Apparently the 'Party Piece' for wire-cutters is for the feed end of the wire to be profiling an elephant whilst the lower end profiles a horse, so you end up with a lump of steel with a horse on one end, an elephant on the other, and a blend of the two in the middle!

As you can see the home workshop can easily afford square broaches of all sizes!

This is the commercial offering of what Steve was talking about above. Called 'Broken Tap Remover' it is of course avaialble on ebay at around £7 per tub. I wanted to remove snapped in 3/8" studs and I was impatient. Consequently I had little success. Barry.

It's best to steer clear of these Dennis people. They are always on the wrong side of the tracks.. .

I always thought the jet number related to flow rate, with a 135 jet passing a flow of 135cc per minute at a specified head. You therefore need a look up table between the jet number and hole size as it is not simply proportional. (...and I few minutes after I wrote this, I read; "First it is to be noted that in a car or lorry engine practice, carburettor jets are graduated in diametrical measurements of the metering orifices, the progressive numbers varying generally in hundredths of millimetres ‑ one millimetre being called 100. In speaking, for example, of a 90 or 95 jet, 0.90 or 0.95 of one millimetre (namely 100) is meant and in a similar manner for a 115 or 120 jet, 1.15 or 1.20 millimetres is meant respectively. " My excuse is that I come from a motorcyle background with AMAL carburettors where it is definitely flow rate which the jet size number refers to! Certainly a little richer mixture will be on the safe side, as Norman suggested. I have always relied on a 'Colourtune' glass spark plug to gauge mixture. With most early Dennis fire engines having twin plug heads it is easy to replace one of the plugs with the glass plug and still be running with all plugs of the correct heat range. Barry.

I doubted the cooling power of a dribble of water, however a 3KW (~ 4 Horse Power ) kettle takes 4 minutes (240 seconds) to boil 3 pints of water, which equates to 40 Horsepower being absorbed for 24 seconds by 3 pints of water. This does not take into consideration the latent heat of vapourisation of water which will give you an extra margin. A gallon of water would therefore absorb the energy of 40HP for at least a minute. However, I am still not convinced that a rise in temperature of this type of transmission brake would lead to reduced braking performance so the water seems unnecessary Roy is correct in saying that the transmission brake is rarely used, with the handbrake being the primary source of braking. On the Dennis the transmission brake is considered to be too fragile for continuous use and is used as an emergency brake only. With the metal to metal contact of the rear brakes activated by the handbrake lever the rear drums do get hot but braking performance is not diminished by the temperature rise. I couldn't help but smile at the small quantities of oil which Tony showed in one of the recent photographs. In particular the Dennis gearbox has a self changing oil facility where the oil constantly drips out and you just keep topping it up with fresh...

I just love the metal to metal squeel! Barry.

The transmission brake originally did not have friction material. It was just metal to metal contact like the rear brakes. Does hot metal have a diffferent coefficient of friction compared with cold metal? Also the brake drum and shoes have so much mass that I would have thought that a dribble of water would make negligible difference in lowering the temperature. Perhaps that is why cooling of the transmision brake was not favoured?

Steve, I didn't see the black radial lines in the centre as cuts, I thought they were just felt tip pen marks. Thinking ahead helps so much! Barry.

Steve, I hope you don't find a wheel! - for I think we would all like to see you make one. Quite casually you say that you will dish your steel template. Surely doesn't an awful lot of metal have to stretch to make it dish. Would it not be easier to cut the rim off, bend up the spokes and then weld a new one (smaller I.D.) back on? Barry.

The Dennis steering wheels were coated in black bakelite which was the first thermo-setting phenolic resin 'plastic' ever produced in 1907. The simplest way to produce this wheel is just to CNC machine it from plate. I just cannot remember how planar they are, but quite possibly you could take it out of 2" plate. On the early Dennis wheels the spokes and hub are separate from the rim. Were you going to extend to this level of originality or just go for a one piece casting?

Sorry, but I tend to disagree! It all depends on how well damped the leaf spring is naturally. I run a 1920 Dennis Fire Engine (weight 5 tons) on solid tyres with well greased leaf springs. It handles just fine. Most early Rolls Royces were fitted with leather spring gaiters which were meant to be packed with grease.

Tony, Just a couple of queries from the last series of pictures. I cannot remember if you said that you had the front springs made. Certainly by looking at the surface finish on the top leaf they look brand new. From the picture of the spring disassembled it seems it was built up without any grease between the faces. Do you have any view on this? I don't think modern springs are greased in this way but I believe it was standard practice in the 'old days'. What material did you use for the exhaust gaskets? Is it an asbestos substitute or the real thing? I have had a go at making copper/asbestos/copper sandwich gaskets using 4 thou copper sheet and with a lot of time and care in folding the copper edges over they can be quite respectable. However for any other HMVF restorer needing unobtainable gaskets (especially cylinder head) I can unreservedly recommend this gentlemen for the most perfect copper asbestos gaskets you will ever see, made to your pattern. Johnson Gaskets 2 Verity Street East Bierley Bradford West Yorkshire U.K.. BD4 6PN Tel: 01274 682298

It is very strange tha there is so much mis-alignment. On all my Dennis's there is always some shimming to align the engine to the PTO, but this can always be measured in thou's of an inch rather than fractions of an inch. You can see one of the shims under the bottom left engine bolt. Barry.

Tony, Does this last photograph show a distributor lurking amongst the decay? Is it complete or is it just the cap? It is far too precious to stay there! Barry

Can we have some more explanation please? Was the rear axle slightly misaligned on the springs? What defines the posiiton relationship between the axle and springs on your lorry? I hope the drive train is going to be complete this Easter! Barry.

Gordon, I think most people who read this thread will only agree with your sentiments. Making parts 'in -house' certainly ins't fashionable. Most 'manufacturing' companies just assemble with all component manufacture sub-contracted out to define part cost and to drive part cost down. It means that sub contractors work on very narow margins and is the reason why so many are disappearing. Machine tools in the UK have never been so cheap as they are now, so it is time to sanp up the Herberts, Harrisons, Colchesters and Bridgeports and carry on the tradition of your 'Hector' which Steve and Tony are doing so well at maintaining, Barry.

If you hadn't already realised, this is exceptionally clever! Steve is using old manual machining techniques which are disappearing from most machine shops. CNC machines remove this kind of thinking necessary to produce such geometry.