Member postings for Cornish Jack

Points to make :-

1. It is an Apple initiative - 'nuff said!

2. These are new children's toys - let them play!

3. A great deal of today's written output (amateur and professional) is in dire need of amplification for meaning!

4. As a fully qualified 'old fart' myself, Dave's (S O D) description is very wide of the mark on a personal basis.

The oft-used example of the Judge's 'out of touch' query is, as I suspect Dave is aware, solely due to the need for recorded evidence to be understood by all - not just by the socially limited 'pop-culture'

standing by for 'incoming'

rgds

Bill

Vic - the accident you refer to was a function of something which is not limited to flyght crew. Car drivers experience similar; if you make the same journey many times, how often do you suddenly reakise that you cannot recall bits of the journey? It's the repetition trick. If you do something over and over again, after a while it becomes automatic and you see and do what you want to see and do without conscious thought. When you do the pre-start/taxi/takeoff checks day-in, day-out and the panels are always correctly set, it takes a mighty effort of will to recognise something out of kilter. Oddly, I suppose that one answer would be for the engineers to deliberately misposiyion the switches/ circuit breakers etc. on every turn round ... not very practical!

The actual solution is a complete, undeviating adherence to check lists - nothing from memory! That's a mantra that stays with me,having nearly ended in the undershoot of an Eastern airport with a Captain who "can't be bothered with those things"

rgds

Bill

A recent (now closed ) thread contained a block graph purporting to show the causes of aircraft accidents and apportioning the majority to 'pilot error'. While it is arguable that that term is applicable in a number of cases, it is also a 'catch-all' get-out for AAIB et al to cover 'cause not known' incidents, It is, for instance, arguable that the recent 737 Max 8 tragedies were 'pilot error' in that they failed to control an aircraft, fully serviceable apart from one designed-in anomaly. It is an area which requires more than usual caution in coming to conclusions.

Just a note for S O Ds graphic title writer - Woodworkers are possibly dangerous creatures but their tools (planes) are relatively safe. AEROplanes, (or aircraft) however, can be a different kettle of fish.

rgds

Bill

Bob - for aircraft radio specific recommendations, log on to www.pprune.org and the Spectators Balcony forum. Full of active, like-minded people who will point you in the right direction.**LINK**

You'll find a wealth of aviation-related content there.

rgds

Bill

Mike - I note that you mention carbon fibre as a possible construction material. Many years ago, I bought a very large roll of c/f tape for model aircraft construction and never got round to using it. Would it be of interest?

rgds

Bill

"the RAF sleep in a Five Star Hotel near the airport. "

I wish!!

First tour 2 years plus in Aden 110+ in the shade, NO aircon, first 8 weeks' accommodation a bed 3 'biscuits' and a bedside locker on an open veranda! En route intended night-stop Castel Benito, concrete slab with straw palliasse, hessian covered in converted stables. Even we drew the line at that and continued to destination - bed-to-bed 52 hours. ... and so on. Oh the silk sheet luxury of it all!!

rgds

Bill

Just to tidy this one up - the DA200 published dimensions are NOT exact. The new and old sets are interchangeable as regards holders.

rgds

Bill

One of the first lessons learned (the hard way!) on S&R helos was DON'T keep contact with the winch cable when you first touch down - ground or water! Wet winching in Holyhead harbour towards the end of a fairly strenuous session on the wire, I forgot! I was breathing hard, mouth open and got a static short across my teeth - amalgum fillings! Quite startling! A few years previously at Thorney Island we were tasked to liaise with the Farnborough boffins doing research on helo static discharge. The boffins were in the Littlehampton lifeboat and we did several runs to check discharge levels. they told us afterwards that the majority were in the 150-170, 000 volts range! Given that I was acting as the end of line conductor, I'm assuming that the current levels were very low.

rgds

Bill

As I understand it, one function of petrol powered car catalytic exhausts is pollution reduction - BUT to be effective, they need to be at working temperature. Diesels, on the other hand, operate at a similar level throughout. The majority of car journeys are short distance, shopping etc. For me, the Q.E.D is obvious but not to our 'Leaders', indeed it's not ever mentioned in the various discussions. Thoughts??

rgds

Bill

Phil - very impressive. The sort of thing I would like to do but age and incompetence rule against!. My query was a roundabout way of finding out if a sale item would be suitable for an existing collet holder.

rgds

Bill

Thank you Jason and Emgee - " if your collets are close to these dimensions should be OK, " ,,, that's what I was after; Yet another raid on the piggy bank!

rgds

Bill

Thank you Neil - I appreciate what you say about possible fragility but my query is actually about identification. The D1 etc. values shown on the 'net are Imperial to 3 decimal places and the items I have differ by 2 or 3 third place values. They are not marked as to type so I'm wondering if I actually have DA200s or some other type? The closeness of approximation is such as to generate a doubt but I can't find acceptable tolerances for collets and holders. Hope that makes sense - (got to be a first time for everything!!)

rgds

Bill

I have some DA collets which were bought secondhand. Checking against the published dimensions I appear to have a partial saet of DA200s. The checked dimensions are CLOSE TO the published for that range, but not exact. What degree of tolerance should one expect for the D1, D2 and L values ? (I'm assuming the holding value will be to spec)

Any advice appreciated

rgds

Bill

Martin X 2 - many thanks - helpful (and reassuring) It would seem that my overly tight fit is the better bet.

Tim - I quite understand the point you make but for the price paid (including delivery from China,) I could have bought half of the materials (if I was lucky) and then produced an object no more accurate than this. I could well have paid more for the super little chuck than the whole package, so no moans from me on that score.

Hollowpoint - indeed - as noted from time to time in these threads.

rgds

Bill

Couple of pics below of some imported components for a drill spindle. Looks to be well made and needs to be assembled. Thereby lies the problem - the tolerances are 'marginal', in that one of the bearings slotted into place with finger pressure., the other is very much an interference fit. The spindle, as is, won't accept either bearing. Not sure what the fit discrepancy is but I've had the spindle in the freezer for a week or so and still not a finger pressure fit in the bearings. I can foresee jamming problems so would greatly appreciate adfvice on best practice assembly routine for spindle to second bearing and then to housing or second bearing to housing THEN spindle through both at the same time.??? Plus any action to the remaining bearing - heating (and how). Ideas very welcome!

rgds

Bill

Michael - the Vitrex are 9", no grade that I can see. The Abrafiles are a mix, some 8", some 9"" and the only ones I can see graded are two VERY old packs of 'Coarse'

HTH

rgds

Bill

Update on the above post. I now have the Abrafile/Vitrex to hand. There are some 20+ packs, all displaying signs of long term storage. 2 packs only of Vitrex, the rest Abrafile. Give or take a penny or so, they will cost £4.20 for a pack of three (something for the weekend, Sir?), plus postage . These will be long-term available (although at 83, 'long-term' maybe a relative value!!)

rgds

Bill

For general info - I have bought the job lot of Abrafiles (and the Vertex copies) which were on Ebay. This was done to prevent the dreadful rip-off pricing which happened last time this product was being sought. Once I have received them I will make them available at cost plus postage in SMALL lots only. I would not expect delivery for at least 7 to 8 days.

The advantage of Abrafile, as against any of the others is the small diameter fixing pins which allow the blade to be started in the middle of a sheet with minimum material loss.

rgds

Bill

Just received the following **LINK**

11 days for delivery and, at the price, appears to be extraordinarily good value. Had a quick look and it all looks good - the bearings spin sweetly, the chuck is a little jewel and the drive pulley looks to be standard. Don't know whether the "only one left" is 'click-bait' but seems a reasonable bet, price-wise.

rgds

Bill

More a matter of the last week or so, watching the start of 37 million quids worth of trying to modify Nature - or, to be precise, the North Norfolk coast. The antics of the accompanying twin-hulled tow craft are quite amazing. one hopes the results will help to avoid a repeat of the 2013 'excitement' !!

rgds

Bill