By: dhfan
- 18th November 2004 at 10:30Permalink- Edited 1st January 1970 at 01:00
I don't suppose there was much need for Rover to change anything. The factory was handed over to them as a going concern, already in full production AFAIK. Their's would be more of a management role than anything else.
As Mark12 said, it does seem difficult to believe Packard would use BA, BSF and BSW threads. In similar vein, the DH Gipsy range of engines used metric threads and they were re-drawn for Australian production.
Greatest piston engine ever? Possibly military but I believe it took a lot of work to get it reliable enough for civil use.
By: Firebird
- 18th November 2004 at 10:34Permalink- Edited 1st January 1970 at 01:00
best inline rather than radial perhaps. I think, as ever, there is some who'd dispute the Merlin being best ever. Damn good though!
My point was that it was arguably the best ever because of that succesful adaption between air/land/sea. I don't believe that could be said of many other inline aero engines (Allison maybe?) and certainley not radials, although, obviously, a Continental radial was used to power the Stuart light tank variants as well as many Shermans.
By: dhfan
- 18th November 2004 at 10:37Permalink- Edited 1st January 1970 at 01:00
As far as design authority goes, I can't believe RR would ever have relinquished it. There was huge reluctance within RR to let any other organisation build their engines, in fact for a long time, point-blank refusal.
By: Mark12
- 18th November 2004 at 13:48Permalink- Edited 1st January 1970 at 01:00
I don't suppose there was much need for Rover to change anything. The factory was handed over to them as a going concern, already in full production AFAIK. Their's would be more of a management role than anything else..
I would be pretty sure that many parts from the Merlin would interchange with the Meteor engine as fitted to the Centurion tank.
I think the Aviation Jersey core business was the reconditioning of said engines for Centurion export customers around the world.
Using Meteor parts in an airworthy Merlin is a different matter. They might well interchange but are unlikely to have been manufactured to the same stringent processes, fine limits and quality control the the civil and military authorities would require in recent years.
Mark
New
Posts: 39
By: crystal lakes
- 18th November 2004 at 14:55Permalink- Edited 1st January 1970 at 01:00
Detroit Diesels
Mark 12
Those darned Detroits, they remind me of a Perkins.
Mike
By: TempestNut
- 19th November 2004 at 09:20Permalink- Edited 1st January 1970 at 01:00
The point about thread types on studs and fixings is a good one. There is no mention in the summary of all Rolls Merlin/Griffon engines in their 'Aero Service Bulletin' of 1950. Anybody have the definitive answer to this one?
It is hard to imagine the Americans building Merlins for Mustangs with BA, BSF & BSW threads.
Mark
Just found a reference to the threads. All Merlins and V1650s were produced with BA, BSF, BSW threads. Packard could not source its fasteners in the US so it decided to produce its own high quality fasteners. Source Graham White
By: soaringtractor
- 12th October 2016 at 05:17Permalink- Edited 1st January 1970 at 01:00
numbers of Melins made
Just wondering how many Merlins were built by Ford, Packard and Rolls-Royce - does anyone know the production figures?
Packard produced 55,385 Merlins Ford of UK produced 30,000 of the total of 168,000 so RR only produced one half the total, Packard about one third the total
By: dhfan
- 12th October 2016 at 15:45Permalink- Edited 1st January 1970 at 01:00
Re threads etc.
In the 12 years (!) since this thread was live I'm sure I've read that not only could Packard not find anybody to make the fasteners, they couldn't find anybody to make the tooling either, so they made their own taps, dies, etc.
Don't ask where I got it from - not a clue. (Hooker?)
By: TempestNut
- 12th October 2016 at 22:19Permalink- Edited 1st January 1970 at 01:00
Seeing as this has opened again and we are talking about threads. Another gem I came across about threads was that the angles of cut or roll (depending on how the fixing was manufactured and what it was for) of the BA, BSF, BSW threads was the ideal for maximum strength, and are the threads we should have dominated the world with. But because there was a patent on these angles the metric threads we now use are not ideal and we lose a little for that. Of course modern manufacturing and materials negate much of the engineering advantage, but it does serve to illustrate the brilliance of the early engineers. The tools for BA, BSF, BSW threads were always labelled as per the bolt size, where as SAE and Metric always labelled tools as per the head size. Today with the star headed bolts we see the tools often again labelled as per the bolt size again. So everything changes but nothing is new.
By: dhfan
- 13th October 2016 at 16:23Permalink- Edited 1st January 1970 at 01:00
Whitworth devised his thread in 1841. Surely any patents would have long elapsed before other standards were issued.
Wiki says American engineers simplified their threads from Whitworth's 55° rounded profile to 60° flat-topped but I've not got any reference material to back that up.
The only sockets I've got for star-headed bolts are labelled E10, E12 etc.. Without taking my car to bits I can't be certain but I'm sure the bolts for those sizes are no larger than 5 or perhaps 6mm at the most.
By: Ossington
- 13th October 2016 at 18:58Permalink- Edited 1st January 1970 at 01:00
I remember reading somewhere that BI (RR built) Lancasters (and thus very likely old re-treads) were preferred on Lancaster Finishing Schools to brand new BIIIs when given a choice, because the constant 'circuits and bumps' that they were put through 'overheated' the Packards early. I think it was meant that the Packards couldn't shed the excess heat off quickly enough. How could this be, if they had an identical radiator set up? Does this tale stand up to scrutiny? Is there an engineering explanation? Or maybe brand new aircraft, with all the recent mods already fitted, were much preferred for the front line, leaving high-hour re-treads for the training establishment?
By: Graham Boak
- 13th October 2016 at 21:15Permalink- Edited 1st January 1970 at 01:00
I don't think the overheating story holds water (or glycol) but there's no doubt that the Operational Training Units and Conversion Units were issued with the older aircraft that had already seen service, whereas the operational squadrons received new aircraft whenever possible.
By: powerandpassion
- 14th October 2016 at 06:41Permalink- Edited 1st January 1970 at 01:00
This scandalous anti-antipodean thread title must be changed to incorporate the CAC Lidcombe built Australian Merlin 102, which is universally recognized, once I have edited Wikipedia, as the "best engineered, most successful and most highly developed Merlin variant". Not only was it lighter, faster and more powerful, these attributes grow the more fine Australian beer you consume.
As an aside to this cruel northern hemisphere malignment, the habit of redrawing original plans was applied to this engine program. I know this because the bloke who did it wallpapered his toilet in Merlin engine drawings once the Lidcombe Merlin program shut down, no doubt to northern hemisphere perfidy and chicanery and beer watering sneakiness..
By: powerandpassion
- 14th October 2016 at 07:01Permalink- Edited 1st January 1970 at 01:00
As a scientific comment, the efficiency of liquid to air heat exchangers, never great, is affected by ambient air conditions, so the radiator that performs well in cool, dry air performs less well in warmer, wetter air. Perhaps the correlation between where whingeing about where overheating occurred and geography may show that the same cooling system in Malta performed differently to when it was in Manchester. So there would be maintenance fitters in squadrons stationed in wetter air that rightly formed a consensus that one product was ****e while others in different conditions could form the opposite view. In true science there would be a 'test and control', a multi engine aircraft with both Packard and UK built engines subject to the same conditions.
Methinks there were other factors, such as the design of the exhausts, as much heat energy is dissipated through these, and a more restrictive exhaust would retain more heat in the engine. In also thinking through material substitution for CCF Hurricane structures, the materials were different to UK built Hurricanes, so I wonder if the aluminium used in US built RR engines may have been a different alloy, with different heat transmission characteristics. I am sure it was, but this would be a fractional contributor.
Most of it would be in the design of the radiator, in the surface area in contact with air. Much of the original problem is getting an engine 'up to heat' in a freezing winter, so a tropical radiator would be different to a winter radiator, if there was enough time to work this out. I think it is plausible that aircraft were rushed into service that had cooling systems configured for different climates, creating whingeing, which is a, er, um a [redacted nationality] trait.
Again, no problem with the superbly resolved, lighter, faster Australian CAC Lidcombe built Merlin, designed to cope with Darwin heat. Surprisingly good climate to drink chilled beer in too!
By: detective
- 14th October 2016 at 10:28Permalink- Edited 1st January 1970 at 01:00
it's just so lovely to see that a thread from around 14 years ago can elucidate and glean more information about the finer points of these engines with the " new " knowledge to be had from today's thoughts and technology... tip 'me bloody hat.
Posts: 8,195
By: JDK - 18th November 2004 at 10:15 Permalink - Edited 1st January 1970 at 01:00
best inline rather than radial perhaps. I think, as ever, there is some who'd dispute the Merlin being best ever. Damn good though!
Posts: 2,890
By: dhfan - 18th November 2004 at 10:30 Permalink - Edited 1st January 1970 at 01:00
I don't suppose there was much need for Rover to change anything. The factory was handed over to them as a going concern, already in full production AFAIK. Their's would be more of a management role than anything else.
As Mark12 said, it does seem difficult to believe Packard would use BA, BSF and BSW threads. In similar vein, the DH Gipsy range of engines used metric threads and they were re-drawn for Australian production.
Greatest piston engine ever? Possibly military but I believe it took a lot of work to get it reliable enough for civil use.
Posts: 2,108
By: Firebird - 18th November 2004 at 10:34 Permalink - Edited 1st January 1970 at 01:00
My point was that it was arguably the best ever because of that succesful adaption between air/land/sea. I don't believe that could be said of many other inline aero engines (Allison maybe?) and certainley not radials, although, obviously, a Continental radial was used to power the Stuart light tank variants as well as many Shermans.
Posts: 2,890
By: dhfan - 18th November 2004 at 10:37 Permalink - Edited 1st January 1970 at 01:00
As far as design authority goes, I can't believe RR would ever have relinquished it. There was huge reluctance within RR to let any other organisation build their engines, in fact for a long time, point-blank refusal.
Posts: 10,029
By: Mark12 - 18th November 2004 at 13:48 Permalink - Edited 1st January 1970 at 01:00
I would be pretty sure that many parts from the Merlin would interchange with the Meteor engine as fitted to the Centurion tank.
I think the Aviation Jersey core business was the reconditioning of said engines for Centurion export customers around the world.
Using Meteor parts in an airworthy Merlin is a different matter. They might well interchange but are unlikely to have been manufactured to the same stringent processes, fine limits and quality control the the civil and military authorities would require in recent years.
Mark
Posts: 39
By: crystal lakes - 18th November 2004 at 14:55 Permalink - Edited 1st January 1970 at 01:00
Detroit Diesels
Mark 12
Those darned Detroits, they remind me of a Perkins.
Mike
Posts: 474
By: TempestNut - 19th November 2004 at 09:20 Permalink - Edited 1st January 1970 at 01:00
Just found a reference to the threads. All Merlins and V1650s were produced with BA, BSF, BSW threads. Packard could not source its fasteners in the US so it decided to produce its own high quality fasteners. Source Graham White
Posts: 2,890
By: dhfan - 19th November 2004 at 10:59 Permalink - Edited 1st January 1970 at 01:00
Well done, that man. Settles it then.
Posts: 2
By: soaringtractor - 12th October 2016 at 05:17 Permalink - Edited 1st January 1970 at 01:00
numbers of Melins made
Packard produced 55,385 Merlins Ford of UK produced 30,000 of the total of 168,000 so RR only produced one half the total, Packard about one third the total
Posts: 2,890
By: dhfan - 12th October 2016 at 15:45 Permalink - Edited 1st January 1970 at 01:00
Re threads etc.
In the 12 years (!) since this thread was live I'm sure I've read that not only could Packard not find anybody to make the fasteners, they couldn't find anybody to make the tooling either, so they made their own taps, dies, etc.
Don't ask where I got it from - not a clue. (Hooker?)
Posts: 474
By: TempestNut - 12th October 2016 at 22:19 Permalink - Edited 1st January 1970 at 01:00
Seeing as this has opened again and we are talking about threads. Another gem I came across about threads was that the angles of cut or roll (depending on how the fixing was manufactured and what it was for) of the BA, BSF, BSW threads was the ideal for maximum strength, and are the threads we should have dominated the world with. But because there was a patent on these angles the metric threads we now use are not ideal and we lose a little for that. Of course modern manufacturing and materials negate much of the engineering advantage, but it does serve to illustrate the brilliance of the early engineers. The tools for BA, BSF, BSW threads were always labelled as per the bolt size, where as SAE and Metric always labelled tools as per the head size. Today with the star headed bolts we see the tools often again labelled as per the bolt size again. So everything changes but nothing is new.
Posts: 2,890
By: dhfan - 13th October 2016 at 16:23 Permalink - Edited 1st January 1970 at 01:00
Whitworth devised his thread in 1841. Surely any patents would have long elapsed before other standards were issued.
Wiki says American engineers simplified their threads from Whitworth's 55° rounded profile to 60° flat-topped but I've not got any reference material to back that up.
The only sockets I've got for star-headed bolts are labelled E10, E12 etc.. Without taking my car to bits I can't be certain but I'm sure the bolts for those sizes are no larger than 5 or perhaps 6mm at the most.
Posts: 124
By: Ossington - 13th October 2016 at 18:58 Permalink - Edited 1st January 1970 at 01:00
I remember reading somewhere that BI (RR built) Lancasters (and thus very likely old re-treads) were preferred on Lancaster Finishing Schools to brand new BIIIs when given a choice, because the constant 'circuits and bumps' that they were put through 'overheated' the Packards early. I think it was meant that the Packards couldn't shed the excess heat off quickly enough. How could this be, if they had an identical radiator set up? Does this tale stand up to scrutiny? Is there an engineering explanation? Or maybe brand new aircraft, with all the recent mods already fitted, were much preferred for the front line, leaving high-hour re-treads for the training establishment?
Posts: 957
By: Graham Boak - 13th October 2016 at 21:15 Permalink - Edited 1st January 1970 at 01:00
I don't think the overheating story holds water (or glycol) but there's no doubt that the Operational Training Units and Conversion Units were issued with the older aircraft that had already seen service, whereas the operational squadrons received new aircraft whenever possible.
Posts: 526
By: Versuch - 14th October 2016 at 00:17 Permalink - Edited 1st January 1970 at 01:00
The father of a guy I worked with flew Lancasters (101 Sqn), and he mentioned that he liked the Roller built version as the" Packards ran hot".
Posts: 1,354
By: powerandpassion - 14th October 2016 at 06:41 Permalink - Edited 1st January 1970 at 01:00
This scandalous anti-antipodean thread title must be changed to incorporate the CAC Lidcombe built Australian Merlin 102, which is universally recognized, once I have edited Wikipedia, as the "best engineered, most successful and most highly developed Merlin variant". Not only was it lighter, faster and more powerful, these attributes grow the more fine Australian beer you consume.
As an aside to this cruel northern hemisphere malignment, the habit of redrawing original plans was applied to this engine program. I know this because the bloke who did it wallpapered his toilet in Merlin engine drawings once the Lidcombe Merlin program shut down, no doubt to northern hemisphere perfidy and chicanery and beer watering sneakiness..
Posts: 1,354
By: powerandpassion - 14th October 2016 at 07:01 Permalink - Edited 1st January 1970 at 01:00
As a scientific comment, the efficiency of liquid to air heat exchangers, never great, is affected by ambient air conditions, so the radiator that performs well in cool, dry air performs less well in warmer, wetter air. Perhaps the correlation between where whingeing about where overheating occurred and geography may show that the same cooling system in Malta performed differently to when it was in Manchester. So there would be maintenance fitters in squadrons stationed in wetter air that rightly formed a consensus that one product was ****e while others in different conditions could form the opposite view. In true science there would be a 'test and control', a multi engine aircraft with both Packard and UK built engines subject to the same conditions.
Methinks there were other factors, such as the design of the exhausts, as much heat energy is dissipated through these, and a more restrictive exhaust would retain more heat in the engine. In also thinking through material substitution for CCF Hurricane structures, the materials were different to UK built Hurricanes, so I wonder if the aluminium used in US built RR engines may have been a different alloy, with different heat transmission characteristics. I am sure it was, but this would be a fractional contributor.
Most of it would be in the design of the radiator, in the surface area in contact with air. Much of the original problem is getting an engine 'up to heat' in a freezing winter, so a tropical radiator would be different to a winter radiator, if there was enough time to work this out. I think it is plausible that aircraft were rushed into service that had cooling systems configured for different climates, creating whingeing, which is a, er, um a [redacted nationality] trait.
Again, no problem with the superbly resolved, lighter, faster Australian CAC Lidcombe built Merlin, designed to cope with Darwin heat. Surprisingly good climate to drink chilled beer in too!
Posts: 1,566
By: Malcolm McKay - 14th October 2016 at 10:02 Permalink - Edited 1st January 1970 at 01:00
To be technically correct a merlin built in the US should be called a pigeon hawk.
https://en.wikipedia.org/wiki/Merlin_(bird)
:highly_amused:
Posts: 137
By: detective - 14th October 2016 at 10:28 Permalink - Edited 1st January 1970 at 01:00
it's just so lovely to see that a thread from around 14 years ago can elucidate and glean more information about the finer points of these engines with the " new " knowledge to be had from today's thoughts and technology... tip 'me bloody hat.
Posts: 2,605
By: QldSpitty - 14th October 2016 at 11:52 Permalink - Edited 1st January 1970 at 01:00
I heard the MkXVI Spits had various losses over Europe due to Packards giving up the ghost.