Member postings for John Flack

Sharing a link above, I found myself reading that stainless nuts and bolts MUST be assembled with lubrication, never heard of that before.

Look guys asking a Morgan owner to discuss MGs is a non starter. If you refer to the MG thread discussion site they

talk about mad metric and not using ISO dies to clean FRENCH METRIC studs and suggest shot blasting dies to round up the thread, I'm not making it up this is what TD TF owners are doing😅😅😅😅😅

EUNOIA Please

Richard.........forgot to say the hot metal vaporises the wax impression

Richard.........the whole of the "pattern"is immersed in plaster in a flask with a hole to allow the melt, this is then broken or power jetted to clean up the cast. If multiples are required you immerse your patters in a liquid rubber solution you then have to cut the rubber carefully with a scalpel extract the master and the mould springs back. The pattern has to have an ingate(channel) to allow wax to be injected, thus wax copies are produced which are attached to a central sprue and back to the aforementioned plaster. To complicate matters further the plaster and rubber have to be placed in a vacuum chamber to remove bubbles that might adhere to the original pattern. Mould making can get quite complicated using two half mounds with locating acorns. I am told that good mould cutters, the staff not the knife, are well paid.

The process has been around for thousands ot years originally twirling clay and molten bronze in a centrifugal manner on a rope.

This duplicates what other have written above to show how sophisticated the process is. For a small quantity the caster may be able to include you pattern in a production mould and advise you as the suitability of your patterns

John Stevenson

It's not just the pitch.....the thread angles as well. As I have mentioned else where look up MG TD TF 1500cc which for me is a modern post war car, French metric(not the same as ISO ) with Whitworth sized heads to confuse the spannerman. And they are called "Standards" the evil thing is that with little effort you can force an ISO nut onto the same dia French fine thread stud, probably ONLY once!!!!!!!!!

To suggest testing with a wood or plastic dowel sounds plausible , but will it be accurate to measure the thread angle for the same pitch. My attempt with a cocktail stick and 8 BA...............underwhelmed comes to mind(Using magnifier and scalpel blade)

Are we the last generation? (Sounds rather final) as someone past their sell by date, at the age of 19 I was in forced military service as was my father at the same age. Good old days? I'm pleased that a current youngster of 19 has greater opportunities, and appreciate that fact

The concept of "the promised land" or "tomorrow" are iillusiory as when you reach them they are no longer promised or tomorrow, and a new target has to be created and pursued.

The Paris gun project is interesting. Did not Saddam Hussein have a similar item constructed in the UK and not a single person was aware of what it was(or where it was to be pointed)

Mike Poole

We can reinvent the wheel?

Please not on my lathe, I am only just getting the hang of screwcutting😰😤😤😤😤😤😤😤😤

Ah French fine thread. Important if you own a MG TD TF 1500. As Michael Caine said " not........................................!

Howard L gives solid advice in his post avoiding nugatory tarradiddle BUT as fasteners can be brass, steel, high tensile, half nuts aero nuts etc etc this raises the question should an amateur even consider reusing any fastener of unknown origin? The experienced can make an informed choice, much will depend on the use to which it is to be put.

As an amateur who has rebuilt motor vehicle engines, certain fasteners that I would classify as "stressed" would be replaced with known quality replacements. I would never re use a nylon/aero type nut. Just my personal logic with no science to back it up. The old items being junked to avoid mishaps.

Welcome Eoin.........not many "from the dark side" hereabouts but I will admit to modelling between gauge 0 to3

John

Mike......... Live close to Axminster, Oldie specialising in arm chair erosion , kettle boiling, and railways,available for a chat if you visit APTC or passing by

John

Adverting to MKs original question and his use of thread gauges, are such gauges designed to measure female threads? The ones I own a chunky penknife type design have a blade about 10 MM deep. OK perhaps for traction engines etc, but far to wide for my miniature needs. I have assumed that they are fof measuring male threads. How

do you measure female threads smaller than the depth of the gauge blade, is there an answer??

Box van or brake van?.. BR, GWR etc etc scale drawings or outline shape?. Long wheelbase or short wheel base?

Assuming(?) you mean covered van as opposed to open van and decide on a specific vehicle/company there are societies for GWR LNWR MR SR some of whom hold works drawings. Other specific interest magazines such as the Great Western Railway journal have a content with multiple photos often with dimensioned drawings. Old model railway mags often a source of info. A chap called Ken Wherret (?) produced a booklet of O gauge drawings of various railway companies,which are stated to be dimensioned from the prototype, these can be blown up to a larger size for private use.

My good lady has just purchased a polished granite slab from Tesco Direct AKA chopping board under £15 about usual breadboard size about half inch thick. Might have alternative use???

A check today showed no stock (but not discontinued) might interest the LIDL alert group

The finish is equal to my straight edge. Would impress your mates at coffee break time

Could Ian's real interest be in making large scale pens????????😈😈😈😈😈😈😈😈

Harry W

I regularly use/did use bolts down to 16 BA mainly to replicate bolt detail on patterns for components in gauges 0 - 3

Have a set of "box spanners " made by pressing a range of nuts into the end grain of small balsa section

Asking a question which won't concern the majority, has the specification for 14 BA been changed this century as taps supplied to me no longer fit my elderly stock of nuts.

I don't wish to annoy any body on this forum or to be annoyed by its members (I have the medical profession making a very good job of that) my contribution was to ask"what criteria determines the choice between a coarse or fine thread" informing me that you have standardised on M 8 or M 10 leaves me to ask is that fine or coarse thread. If the response is "Coarse of course"? That still leaves open my question WHY? This was a serious ask as many tyros will be using using historical designs where some understanding of retention strength may be critical when seeking alternative fasteners to that specified

I shall now return to usual state of Eunoia

SOD

Used to do that at school with 1/4 inch items and "caps" my first intro to engineering!!!!!!!

Harry W

That perhaps explains why Mr Prestwich of N 17 used 26 tpi on his products, but why with a reduced hex sized nut??

Checking on a link, we seemed to be overwhelmed for choice. Generally the choice is made for us by those who make whatever eqpt we use. When a bespoke is desired is there a specific criteria to be observed?. I simply look at what is to hand and think "that seems about right" and proceed from there. Assuming(?) fasteners are made to equal tolerances would a fine thread be preferable or non preferred to a coarse thread for general fastening use? If so why?

Chart sizes indicate that 20BA nuts are possible. Has any living soul ever seen a nut of this size, and where can I get some?