Member postings for Nigel Graham 2

Trust a bunch of engineers to complify summat as simple as a bog-roll....

it felt right strange for me.

If I am not caving on a Saturday I usually spend the day at the W&DMES track and club-room, but they are out of reach behind locked gates (school grounds) for the duration even before any decision by the society itself.

Ah well, no excuse for not cutting steel, and after my all-too-usual round of mis-measurements and confusing sides on handed pairs, I completed much of fabricating the boiler-mounts for my steam-wagon.

Now, when I say "caving" it's actually a long-term "digging" project our small team has, to work a way through a very deep mass of limestone and conglomerate boulders to find the cave we believe and hope lies beyond - 150ft deep so far and no sign of breakthrough yet. We generally go underground for 3- 4 hours then retreat, mid-afternoon, to the Club HQ for showers, Tea and Cakes.

Clearly, whilst any outdoor pursuits or even meeting the team socially are presently out of the question, one still has to uphold the niceties, so naturally, I retreated mid-afternoon to the domestic HQ for Tea and Cakes.

Helps me remember it's Saturday.

Only afterwards, I did climb back into the overalls and return to the fray, stopping finally when it became too dusky and cold to work on something standing outside the workshop.

Whilst partaking of the tea & cakes, I enjoyed the play on the radio - a dramatisation of Jules Verne's The Mysterious Island, the sequel I had not previously known he'd written, to 20 000 Leagues Under The Sea.

Thank you for that list, Oldiron.

I had tried to find out if the Tewkesbury show (MSRVS) is on or not but now see its web-site carries a full notice of all the Society events being off, including the internal ones.

Fine work one those photos, Peter!

You've all probably seen that humorous poster Walker Midgeley sell, about being put on Earth to complete a certain number of project so making immortality likely...

I know how that cartoon character feels! Six or seven engineering-related projects including slowly completing fitting out the workshop itself. Still, in Week One of Staying At Home ( a new version of the Bee Gees' song there? It even scans) I've -

Washed the car.

Started sorting and cataloguing the multi-drawer storage units in the body of a bench-height trolley I made as the stand for a Warco sheet-metal former. Rather than individually labelling each little drawer I have lettered the 4 units and numbered the drawers in each (A 1 to 60, B 1 to 24...), with the contents on a spread-sheet print, so it's easy to alter. Also I've found card labels never stay in their mouldings on those plastic drawers.

Mowed the lawn.

Planted onion seeds whose packet bears the legend "Plant before Sept. 2014".

Had a tentative attempt to enter the void under the house, the eventual aim being to secure cables and pipes some bodge-artist has left merely hanging in mid-air across the space. Not sure if being a caver for over 40 years has encouraged me to think I can get down there, or made me more wary!

Rang a few friends to keep in touch in these difficult times. I've heard people on the radio say the present restrictions being the most onerous in the UK "in peace-time". From what I can make out, they are more onerous than in war-time too: in WW2 the main obstacle to ordinary life seems to have been rationing - pubs, cinemas, etc. were all still open a far as possible.

Continued working on the steam-wagon is the vague hope of having it in at least steam-raising condition for a rally that so far at least has not been cancelled as far as I can determine.

I've not had personal dealings with Polly, but they are a well-established company with a very good reputation. I hope they can weather this storm and will be back in full business ere long.

Mowed the lawn for the first time this year. Planted some onion seeds that had been languishing in a corner of the kitchen worktop. It said "Plant before Sept 2014" or thereabouts, on the packet, so we'll see if something in any of them can still remember what it's meant to do.

Otherwise, carried on with the steam-wagon... 3 steps forwards, 2-5 back as usual.

You get the oddest effects when conversations become interleaved!

My Myford mill (2nd hand) came incomplete with bellows. I made an equivalent from surplus butyl pond-liner, after making a pond to keep the garden's frog colony happy.

Mice? Oh yes - I saw one in the garden the other afternoon, picking up dropped seeds below the bird-feeder. I don't mind them there.

I don't know the size of this vice, so this may not help...

With the vice dismantled, can you set the two parts on the bench-drill or mill to drill the screws out and re-tap the holes? They are quite likely either BSF or BSW, so finding replacement screws might be difficult, though.

Thank you John.

Yes, I know the danger of overheating PTFE. Other plastics can emit toxic fumes too, if burnt.

However, these parts are outside the boiler, and a long way from either the fire-hole or grate.

The first requirement is three pads that act as insulation, cushioning and expansion-bearers between the copper shell's mounting-lugs and the chassis. By chance, after submitting the question, I discovered I had an oddment of PTFE plate, and made those pads from it.

For the rest, summarising what I've been advised here, I think my best approach will be hardwood for supporting the lagging and outer cladding.

Some of my source photos suggest the original vehicles having no boiler cladding, but they may have been photographed incomplete to show some of the details. If they were clad, most likely it was with sheet-metal over some insulation material, unknown to me, though possibly wood.

I think the most anyone outside the ventilator-manufacturers themselves can be expected to do is make individual parts, but would have to work under stringent QC measures, at the very least close dimensional inspection, and very likely with full materials-traceability - not to mention extraneous bumph like the ISO9001 management-control scheme.

They would also be expected to make large batches, so probably be given CAD/CAM files for direct use on sophisticated machine-tools; and emergency or not, under conditions of normal commercial confidentiality. To some extent that is made easier by relative anonymity - titling the drawings by part-number alone, for example.

Model-engineers were indeed recruited in WW1 to make parts for shells etc., but modern manufacturing and quality-control methods in fields such as medical equipment are almost certainly beyond all but a few of us now.

Even those of us (well, you, not me) able to take on the work physically may also run up against the problem of insurance. I don't mean of product-liability, because you would be making small parts under rigorous inspection rules from a supplied drawing and possibly supplied materials; but just of household and model-engineering cover. Despite the circumstances this would be a commercial enterprise, outside of what the car insurers call " social, domestic and pleasure ".

So whilst we might all look at our workshops and wonder if we can help, I think wondering is all we can do.

An American pen-friend asked me about panic.

" Panic ?" I replied. " Panic buying yes, but not otherwise. We Britons do not panic. It's not our way. Instead we grumble about it, have another cup of tea then get on with what needs doing! "

Completed the insulating/ cushioning pads for the boiler mounts on my wagon. Started to work out the next stage - building without drawings is rather like chess: you need consider all manner of arcane possibilities well ahead, even down to the accessibility of fasteners. I never was much good at chess....

Had a bit of engineer's block, so took advantage of the fine weather (albeit chilly breeze) to attend to the Nature Reserve, a.k.a. garden, by digging out some weeds and mowing the lawn for the first time - and first time possible - in 2020.

Even then I had to do some " engineering ". My manual mower was made by a leading firm in a European country renowned for high-quality in making things... but not necessarily in designing them. The rattle in one wheel resolved itself by the wheel disgorging a steel dowel, followed by nearly coming off as its retaining polythene "press-stud" crept out of the tube that serves as rigid axle. This led me to discover the dowel was actually a driving-pin, allowed to escape from its fits-where-it-touches hole as the wheel moved sideways.

And as for the grass-box... Useless! It hangs off two crude, pressed-steel hooks so it drags along the ground, throws the clippings back into the blades when you stop, and empties itself "on site" when you lift it to remove for emptying onto the compost heap.

Still, I now have something more lawn than silage-meadow, the nettle patch is back under control and I have started cutting the flowering-cherry logs for seasoning as making wood, not fuel wood. (I had not felled the tree but trimmed it quite drastically as it was over-shadowing next door's garden too much.)

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Perhaps I'll look at another area of the steam-wagon tomorrow, on the principle that a break from a problem may help me solve it when I return to it.

Oh dear! Has someone in the past has abused that machine, possibly by trying to change gear with its drive running? Thinking about it, there should be very little load on that selector though the gear-box may need help by rotating the spindle by hand to align everything..

However, I am a bit puzzled now, and will need to examine my Harrison closely to understand what is damaged on yours.

On my example at least, the selector handle is retained by a nut on a fixed fulcrum pin, has the detent at the top end, and a rigidly-mounted pin at the bottom end that passes through a slot in the casing to engage the selector itself. No grub-screw anywhere.

Thank you gentlemen!

Regarding what was done on the original... I have no idea! The only surviving documents are assorted publicity photographs and few dimensions from the time. My guess is that the boiler was simply bolted down to steel brackets on the chassis - in fact the boiler itself is of partially bolted construction.

I am replicating to one-third size a steam-wagon, not locomotive, which has a lot of details hidden. This can be both blessing and curse. It allows me to use non-prototypical practices or structural arrangements as and where appropriate; but being hidden means the advertising photos do not reveal what was really there!

The boiler I am using is copper, by Western Steam.

I ought really have given as salient details, that the outer firebox is a vertical cylinder with has 3 copper L-brackets silver-soldered to it, one at the back (w.r.t. to the vehicle) and one each side, at its half-height. The relatively short barrel will sit without fastenings in a ring fitted in the back of the smoke-box, as locomotive practice, with much of its weight taken by a cross-member via a reasonably substantial cladding crinoline.

My thought is to run two parallels to the chassis rails for the firebox side brackets, whilst the rear bracket sits on a plate already riveted to a hefty cross-member that will also be one support for the inverted-vertical, mid-mounted engine.

The firebox brackets will need slight expansion freedom whilst keeping the boiler in place, gained by restraining bars and the insulating pads. My query relates to:

1) the pads between the brackets' undersides and the chassis components - they are thin (5mm) and will be busy, as heat-blocks, expansion-bearings and some cushioning of copper from steel;

2) the crinolines. I am allowing for insulation up to half-inch thick. It would bring the outwards appearance a bit closer to scale if I also lag the boiler top; and as I have allowed for a super-heater not on the original, deep cladding will disguise and lag most of the pipework. (The prototype fed the cylinders from a globe-valve serving as regulator, directly on the boiler, via an exposed loop of pipe. In cold weather especially, the poor engine must have been gasping on hot, wet fluff!)

As it happens, after posting that and making another slight change to " design ", I discovered I have a small block of PTFE (I think - white, glossy, slightly soapy feel) and am using this for the bracket pads, but I still need decide what goes under the cladding. I will test very small samples for heat-resistance by " frying " in cooking-oil.

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Dave - Information new to me! I'd naturally assumed most metals are of fairly similar heat-conducting properties, though I knew copper is better than steel. Stainless-steel being a relatively poor conductor surprises me, given its use in saucepans, though perhaps the lower conductivity is far outweighed by other qualities, and anyway a conventional hob loses a lot of heat into the open air. However the mechanical duties of this boiler's mounting are the more important factor.

Jeff - I like the idea of old PCB material. Some are of SRBF so avoid that as you advise, but many are of fibre-glass. I do have some off-cuts of hardwood too, that would be amenable to trimming down. The pads are well away from flames, and won't be seen on the finished assembly, down in dark recesses.

Duncan - good points about how insulation works, and the cost of brass for cladding. I intend sheet-steel, having shared successful experience with it on club-built locomotives. (True to prototype, too!) I'd be reluctant to use cardboard though, since there is always a slight risk of water finding it. You could say that of wood, too, hence my asking about preservatives.

I've found that gear selection on mine can be a bit vague too...

Your thread has made me think I ought examine the machine and see if in fact the detent is a) there and b) working!

I'm not a clock-maker but treating this purely as metal-working, would it be worth making the washer - which can be of almost any reasonably rigid plastic or metal - to dedendum diameter as John Haine suggests, but dishing it slightly so the pressure is applied close to the cut?

One thing's for sure... model-engineering is the hobby least likely to be taken up by a Feng-Shui Consultant.

Could be a challenge to them though...

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'" Yes, I understand the lathe should be aligned NNE by SSW with the headstock at that end... but its 7 feet long, the shed's barely six wide and I've to stand on this side to use it... '"

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Hopper - the part that vanishes never to be seen again, will be. Only, long after you've made a replacement, when looking for some other small part that's rolled off the bench or that which passeth for such; and has become invisible in its turn.

The belt's outer width is more or less the same width as the top of the groove; but more importantly, you are right that it does not contact the groove floor.

Measuring with rope won't give a very accurate answer because the lines of contact will be wrong, but as Redsetter says, there are dedicated calculators or the formula for the purpose.

V ee-Belts are designated by their circumferences and standard widths each designated by a code-letter, and the pulley groove reflects that, so you need know:

- the width of the top of the groove, to establish the belt type;

- the outside diameters of the pulleys (some, by no means all, are marked);

- the distance between centres.

Obviously too the machine needs a good range of adjustment from slack enough to slip the belt off completely or to change ratio on a stepped-pulley (move the smaller end first); to correct tension for running.

A tip: having bought and fitted the correct belt: cut the label from its box and keep it in a safe place so you know the designation (width-code and circumference) for future replacements, by which time the markings on the belt itself may have become illegible.

Similarly with the packaging-labels for other standard parts that wear more rapidly than the machine as whole.

That's so you don't miss whatever tea-breaks you've set yourself.....

I've had two notes though my door, with offer of help a phone call away. One was from next-door-but one but the other from a lady living right down at the end of the street, who must have canvassed everyone. Either that or she knows me better than I know her.

Could be she's a member of the WI so has met me at their monthly public coffee-mornings - I must ask my neighbour!