Member postings for Tony Martyr

On a beam engine I built some years ago the watts govenor was driven through a coiled spring steel 'belt' that was bought as a length, cut to suit and jioned by screwing the tapered end into the cut end. I have no idea where I got this material from - can someone point me in the right direction?

I am a bit concerned that such a drive using vee-groved pulleys might not be able to drive the Double tangye arrangement I have made and have seen in photos that a flat belt has been used - scarf-jointed and glued?

Tony

The posting from Howl is particularly interesting because it reports a TGA from an observer's point of view.

One strange feature of the attacks is that one typically emerges out of the state with no sense of shock or distress.

One truly horrible part of my first case was that I was sent a video of my lecture which I found I could not watch - here was me apparently acting normally but not being conscious of the event at the time - a sort of robot which is the image in the photo that started this posting.

A set of common features of both events was that although I didn't feel nervious they were both big events and I had practiced the content and the timing of each presentation. A consultant said that was probably what enabled me to perform a complex task for so long and why the (unpracticed) question session at the end created the problem in my performance, yet I remained in a TGA state, in the case of the last case for 3 more hours.

I have corresponded with several people who have suffered similar cases and it is difficult to find a common cause but stress must come into it.

Michael - it was worded perfectly because the whole concept and experience is bizarre.

I did not relate this but 4 years later I had a repeat event. I gave a talk to a local U3A group and remember only arriving at the venue. I gave the talk, cracked jokes, and once again started to behave strangely during questions. Luckily my sister was in the audience and got me out. 4 hours in Hereford hospital and I suddenly 'came out of it' as my wife was driving me home. I have absolutely no recall of anything inbetween and never will have. The Consultant said to me "if you decide to murder anyone and claim TGA as a defense please call me as your prime witness". So was I conscious ? not really but fully functional. I don't give lecture any more - except to my grandchildren.

'TGA by proxy' is a mind-bending concept.

How about inventing a self-test one could run each morning to prove that you are, or are not, laying down memory (in TGA state) - in fact it is impossible.

The photo used as my forum portrait was taken during the time I was giving a presentation to an engineering conference in Graz, Austria. The point of interest is that during the 6 hours preceding the lecture and for the one hour it took, I was in a state of Total Global Amnesia (TGA) which means that although apparently rational and giving a coherent talk I was laying down no memory. I remember going to bed the night before but the next memory was being aware of being asked in German to count a medic's fingers while we sat in an ambulance.

That morning I had dressed, had breakfast, talked to colleagues, taken a taxi, listened to lectures and had lunch before my lecture. A friend sitting in the front row realised something was wrong when I was asked the first question at the end of the talk - I started the talk over again!

A stroke was suspected, but TGA is benign, except that it is deeply unsettling, and cases of long duration and complex actions are quite rare. Graz is the site of the Sigmund Freud Institute where I was sent for 3 days having every test known to man before being passed out as fit but bewildered. I will never get my memories of the day back because I never saved them. I look at that photo a wonder what the hell is going on in there!

Tony

I have consider the 'send them back' option and may do so but if the hole positions are clear of the chill (which is full depth on the edges) they will be usable. It is many years since learning about chemistry of cast iron, I seem to remember that I found it about as boring as the chemistry of boiler feed water in power stations

The job of machining two small valve chamber covers should be a nice simple task - in fact the job was saved for a relaxing evening.
But the whole outer edges of both cast iron pieces are chilled and can't be milled. A tipped lathe tool makes an impression but tends to 'bounce' leaving high spots. I have reverted to rubbing the machined surface on a blued-up surface plate and carefully grinding the high spots with a Dremel. A surface grinder would be nice!

Tony

I need to temporally attach two thin Bronze flanges to a casting's face in order to drill through 10BA holes on a 15mm PCD all mounted on a dividing table. What loctite would you use? there will be little lateral force applied during drilling but it is essential for no movement to take place and de-mounting causes no distortion or surface damage.

In a previous life I used to glue thin brass sheets to a face-plate when turning the knife edges on windage baffles, then release them with a hot-air gun - but I can't remember what grade of loctite we used.

Tony

I used an Evostick impact adhesive to glue the footwell lining in my Caterham some years ago. I had to lie on the ground with my head right under the dashboard and it took some time to get it done. Immediately upon completion my wife drove me to dinner with some friends - I had just got to their front door when I projectile vomited and passed out (quite an entrance). The doctor explained that breathing deeply in a confined space the trichlorethylene fumes was not a good idea.

Thanks for the advice Guys - I have some 638 and will use it on all the spindle connections into the balls. I have used silver-solder paste to assembly the lower arms which took care but worked because the component were all of similar size (thermal mass) but it won't work with fitting a same rod into a comparatively massive ball - so loctite it is.

Tony

Edited By Tony Martyr on 04/05/2020 09:33:13

I am building, in steel, the watts type governor of a Double Tangye engine the bottom arms of which cradle the balls via a 1/16" pin through its centre. The top arm, also 1/16" steel fits into a 1/3rd depth hole in the ball. having made the bits (without breaking a 1/16 drill) I am faced with the job of sticking the mechanism together and am seeking advice as the best (least messy) method of fixing the thin parts into the ball and cradle. Locite, Araldite, soft solder or silver solder (paste).

Suggestions based on experience very welcome.

Tony (absent from hands-on engineering for best part of a year while writing two books, one published and the last is with the copy-editor)

Edited By Tony Martyr on 03/05/2020 13:28:06

The local Museum is taking one of my model engines as a long term exhibit. It is a semi-rotary beam engine and much of it is in bronze and brass, painted and exposed. I am concerned about how the exposed steel parts should be prepared. The museum is fitted with dehumidifiers that run year round so I wonder if just a light oiling will be sufficient or if I should use some sort of more longterm preservative - any ideas welcome!

Tony

Thanks for this Jason

I rather feared it was something like your reply - but with only about 7 thou radial clearance between rod thread and hole the distance between the valve face of the cylinder and the centre-line of the valve rod is a 'bit critical'. The counter boore of 1/4" in the bck face must be the contain one of the locking collars/nuts.

Thank for your reply - Tony

The single drawing of the double Tangye engine I have doesn't show the method of attachment of the slide valve to its rod. The valve has a 1/8" hole through which the 6BA portion of the rod must run but I can't see how there is any vertical freedom of movement allowed so that the steam pressure seats the valve on its face while retaining fixed axial position on the rod. My previous engines have had groves in their top faces that housed cruciform ends to the rod - I must be missing something obvious!

I have a 12"x12" cast iron engine base that, in addition to a couple of chilled hard areas, has a series of small 'blow holes' on one flank. This do not create a problem to the structure but don't look nice so I want to fill them before prime and finish painting - but with what? The base is far enough away from the working parts not to suffer any great temperature gradient but it would be embarrassing if bits dropped out.

Tony

Yes Martin, all the obvious problems have been carefully checked

given the total lack of outward signs I will blame the printed circuit because I'm a 'rude mechanical'

I have a DM-18 variable speed milling and drilling machine which has given excellent service for the last 9 years but this morning, while fly-cutting an iron casting I hit a chill spot and the machine was stalled. I banged the EM stop and no obvious damage was done but the machine is now dead.

The drive system has been checked as OK, the electrical feed is OK and there is no electrical smell. In side the control box there is no sign of fuses so I am at a loss to know what has failed - any ides welcome

Tony

Thanks for the comments which all raise a couple of interesting points:
First: I had no problem in finding major and minor engineering and infrastructure projects, modern and ancient, that have failed to either meet specification or were delivered late and/or ran over budget; this was the theme of my book. But having studied and worked in projects for nearly 50 years it occurred to me that domestic or private projects are subject to the same basic laws and can fail for the same underlying causes as major ones so a thirst of my book is that most of us are project managers at some time in our lives and its helpful to understand why they can fail. The classic domestic project I use is the major refurbishment of your kitchen which has all the classic complexities of spacial and temporal planning plus legislation, sub-contracting and cost control.
Secondly: model engineering project fail to meet any sort of reasonable program through procrastination and some of you have recognised this and suggested reasons.
Third: Model engineers (me particularly) sometimes make the classic error of community projects (the village hall etc) who put all the effort into raising the funds and when the project is complete find that maintenance has either been forgotten or doesn't raise any interest - many 'millennium projects' have failed in this way. I built a 3.5" William loco and once it had run under steam it has been covered in dust under a bench - not a lasting project success!

Fourthly: The latest statistics from the USA states that: only 16.2% of industrial IT projects were completed to the customer's satisfaction and on time. Of the remainder 31.1% were cancelled during the course of the project leaving 52.7% that failed to meet the customer's expectations and/or were over-budget and/or late.

Finally my book should be dedicated to the XXXXXX who have taken us into XXXXX with absolutely no agreed idea of what the final deliverable should be which breaches my Law Zero: "No project should be allowed to proceed without clear specification and acceptance criteria, that are understood by all participants"

Tony

Edited By Neil Wyatt on 06/02/2018 19:07:11

I have a contract with a US based publisher and have just sent off the finished draft of a book provisionally entitled 'Why projects fail ..'
Due to an absolute word limit of 60,000 words imposed on me I had to chop out all the examples of good and bad practice relating to model engineering (!) which was a shame because it produces some classic breaches in the basic laws of project control, but was considered to be of such a minority interest that it was 'left on the cutting room floor'.
Some of my basic laws such as: 'Sometimes the best solution to a problem is not to have it' and 'Paper is cheaper to change than concrete' or 'Nine women can't produce a baby in one month' can be adapted to our hobby quite easily - If I wasn't so busy with real life I would suggest a couple of magazine articles. meanwhile if any reader is brave enough to describe a model engineering project failure and its root cause I will (while preserving anonymity) develop the raw material for future publication
Tony

Thanks to all and particular to JasonB for the inclusion of the part section drawing.

I have a copy of the single Westbury drawing from Reeves which does not show the position of the cylinder drain hole which justifies the unusual flange hole distribution.

The drawing raises a larger point - how will we get the younger generation of engineers to follow in our hobby if these very poor imperial dimensioned drawings are the only design source material? I have spent my life involved with gearing and engines and have built a few models but even to me this drawing of the Double Tangye is more of an initiative test than an aid. I haven't located a copy of the articles that originally aided the construction. My interest in the engine was raised by seeing a unit at the Broomy Hill Engine site in Hereford - I'll go back on the next 'steaming day' and count the bolts.

Tony