WW1 Thornycroft restoration

[Old Bill]

Wing nuts can be clearly seen in the drivers' manual so we have continued their use. Those I found twenty years ago are of a modern pattern. Since then, the internet has come along and Dad has found the correct pattern quite easily so we will replace them in due course. The Dennis box was secured with nuts and washers (Again visible in the manual). However, it also has a filler on the front of the case with a cover. That is fixed using wing nuts. I would suggest that this would allow the driver to top up the box with no tools to hand.

 

Regarding the 'gate' this is just the same as the Dennis with reverse through first and a trigger to allow the lever to move to that position. I'm not sure how common this was but I have seen it elsewhere.

 

Cheers!

 

Steve

[Roy Larkin]

Regarding the 'gate' this is just the same as the Dennis with reverse through first and a trigger to allow the lever to move to that position. I'm not sure how common this was but I have seen it elsewhere.

 

Cheers!

 

Steve

 

Maybe something to do with the War Office conditions for acceptance under the subsidy scheme. All gear change gates had to be the same so that a driver could change to different makes of lorry and be able to drive it without re-training. pedal layout, position and operation of controls were all determined by the War office.

[GeePig]

Tony, surely your Dennis gearbox was just like this with a cover plate and wing nuts?

 

Barry.

 

[ATTACH=CONFIG]76361[/ATTACH]

 

Oh look, Mr. Dennis Patent keeps his doorknob very shiny!

 

Seriously, what is that brass thing on the cover? Is it just to lift the cover?

 

Trevor

[Asciidv]

Oh look, Mr. Dennis Patent keeps his doorknob very shiny!

 

Seriously, what is that brass thing on the cover? Is it just to lift the cover?

 

Trevor

 

 

...here is amother door knob this time on the top of the PTO. As you will see it is just a rather smart 'breather'. The advantage (or sometimes disadvantage) of having a fire engine is that all the brass bits have to sparkle - and yes it is cheating if you laquer it over to save effort later on.

 

 

 

Barry.

Edited May 11, 2013 by Asciidv

[Great War truck]

Steve is still very busy trying to move house. He has, however cleaned up the oil pressure regulator which had, quite remarkably , survived on the half-engine which came from Buxton. It is a simple device where the oil is fed in from the side, underneath a piston which is held on its seat by a spring. When the correct pressure is achieved, the piston lifts and the oil runs through the centre of the body, emerging through the bottom which is directly above the timing gears. A good clean and a new centre bolt were all that was required and it is now safely stored away ready to fit.

 

 

 

 

 

 

 

On another front, Father delivered the piston patterns to the foundry this week. After some discussion, we have decided to do away with the chucking piece on the crown and to use the draw-bolt method of mounting them in the lathe. This will reduce any residual stresses in the crown and make the whole lot more stable when cutting the ring grooves.

[super6]

Out of curiosity seeing as there appear to be quite a lot of brass fittings to these engines, are they painted or left in the raw so to speak? My personal view is that they would have been painted as bright shiny bits on a military lorry wouldn't do, but what do I know?

[Minesweeper]

Out of curiosity seeing as there appear to be quite a lot of brass fittings to these engines, are they painted or left in the raw so to speak? My personal view is that they would have been painted as bright shiny bits on a military lorry wouldn't do, but what do I know?

 

If there is a difinitive answer to this one then perhaps Roy Larkin can come up with it from his great collection of records and procedures of that time!

 

But this was war time and I would think that the objective was to get the lorry on the road as quickly as possible, as safely as possible, as reliable as possible and with the minimum done, but still keeping the crew as safe as possible. Only paint where it is essential.

 

So with those objectives in mind, I would expect to see any bright object painted over if it was going to be visible to an enemy. Anything not visible but made of a bronze, brass or copper and which is tucked away would not be painted as the sort of corrosion that you would have with ferrous materials which need paint protection would not apply so painting for that purpose would be unneccesary.

 

In later years, we used to say that "bull s**t baffles brains" and it could well be that some bright fittings were continually polished to look smart if that was a Regimental or Unit procedure.

 

Tim does have in his collection, a picture of a lorry that has been "highly bulled" for a competition - and if I remember, it is painted with glossy paint, too"

 

Tony

Edited May 20, 2013 by Minesweeper

[flandersflyer]

Out of curiosity seeing as there appear to be quite a lot of brass fittings to these engines, are they painted or left in the raw so to speak? My personal view is that they would have been painted as bright shiny bits on a military lorry wouldn't do, but what do I know?

take a look at the beardmore engine then here:

 

is this enough brass n shiny bits for you?..lol

these were fitted to the FE.2b aircraft....which was an artillary flyer/observation aircraft used by the RFC during WW1.

Beardmore were from Glasgow and their engines had a reputation for being very reliable and of good workmanship.

 

to the O/P:

how do you find the general construction & design of the Thornycroft in comparison to the Dennis?

from where I am looking I would say the thornycroft was a superior product....but then again I can only speculate as I am not there on the scene to witness construction close up..

although the pics and talk you are providing is outstanding and will in itself prove to be an important historical document in time.

Keep it coming fellas.

Glenn.

GLMelectrical

Edited May 19, 2013 by flandersflyer

[GeePig]

...here is amother door knob this time on the top of the PTO. As you will see it is just a rather smart 'breather'. The advantage (or sometimes disadvantage) of having a fire engine is that all the brass bits have to sparkle - and yes it is cheating if you laquer it over to save effort later on.

 

[ATTACH=CONFIG]76399[/ATTACH]

 

 

Barry.

 

Thanks, Barry, now I cannot believe I didn't think of a breather :nut:

[Roy Larkin]

If there is a difinitive answer to this one then perhaps Roy Larkin can come up with it from his great collection of records and procedures of that time!

 

But this was war time and I would think that the objective was to get the lorry on the road as quickly as possible, as safely as possible, as reliable as possible and with the minimum done, but still keeping the crew as safe as possible. Only paint where it is essential.

 

Tony

 

Thanks, Tony! I would have to say that the definitive answer is (in no particular order) 'yes, no, maybe, possibly'. Too many variables, I think, - individual companies may have had their own individual policies. Were engines painted after ancillaries were added, if so, probably everything was painted, if they were fitted after painting the block, probably not, unless they were painted before fitting. Company workshops were probably less likely to paint everything than Heavy Repair Shops with MRUs somewhere in between.

 

Speed was less important than getting it right, though, with MRUs throughput seems to have been a factor, but more to prevent a build up of waiting vehicles than the need for repaired vehicles for work. Company workshops appear to have done the minimum, MRUs completed the repair plus their version of overhaul and certainly repaired faults they found over and above the breakdown, Heavy Repair Shops overhauled to 'as new' spec and standard.

 

I'm not sure they considered shiny bits being seen by the enemy as a reason to paint. Even shiny bits dull somewhat when covered in dust or mud and the enemy were never really that close, at least not close enough to spot a shiny hub cap or fuel line under a bonnet. I suspect every external piece of brass was painted simply because it was easier to paint everything than paint round bits. Also, shiny bits would have provided more of a temptation to locals for 'borrowing' to sell on as salvage. Salvage would have fetched a decent price, especially at a time when the local farmers were having their fields turned into battle fields.

 

As for definitive, well, I'm sure there is definitive somewhere, I just wish that every time I find definitive that something else wouldn't turn up to contradict it.

[Jimmy F]

I bring nothing of use to this thread, but I am loving reading it. Cannot wait to see the finished product. I think I may have genuinely drooled at several occasions!

[super6]

I would have to say that the definitive answer is (in no particular order) 'yes, no, maybe, possibly'.

Thanks to all who answered, have to say this was my favourite answer as it covers all possibilities, definitively :-D

Another question, what does MRU stand for? something repair unit? I suspect the M is really obvious but it escapes me at the moment.......

[Caddy]

Medium Repair Unit?

[flandersflyer]

Thanks, Tony! I would have to say that the definitive answer is (in no particular order) 'yes, no, maybe, possibly'. Too many variables, I think, - individual companies may have had their own individual policies. Were engines painted after ancillaries were added, if so, probably everything was painted, if they were fitted after painting the block, probably not, unless they were painted before fitting. Company workshops were probably less likely to paint everything than Heavy Repair Shops with MRUs somewhere in between.

 

Speed was less important than getting it right, though, with MRUs throughput seems to have been a factor, but more to prevent a build up of waiting vehicles than the need for repaired vehicles for work. Company workshops appear to have done the minimum, MRUs completed the repair plus their version of overhaul and certainly repaired faults they found over and above the breakdown, Heavy Repair Shops overhauled to 'as new' spec and standard.

 

I'm not sure they considered shiny bits being seen by the enemy as a reason to paint. Even shiny bits dull somewhat when covered in dust or mud and the enemy were never really that close, at least not close enough to spot a shiny hub cap or fuel line under a bonnet. I suspect every external piece of brass was painted simply because it was easier to paint everything than paint round bits. Also, shiny bits would have provided more of a temptation to locals for 'borrowing' to sell on as salvage. Salvage would have fetched a decent price, especially at a time when the local farmers were having their fields turned into battle fields.

 

As for definitive, well, I'm sure there is definitive somewhere, I just wish that every time I find definitive that something else wouldn't turn up to contradict it.

I wonder if the crew of `Fray Bentos` thought this?

[Roy Larkin]

Thanks to all who answered, have to say this was my favourite answer as it covers all possibilities, definitively :-D

Another question, what does MRU stand for? something repair unit? I suspect the M is really obvious but it escapes me at the moment.......

 

MRU is Mobile Repair Unit.

[Roy Larkin]

I wonder if the crew of `Fray Bentos` thought this?

 

The lorries were certainly close enough to be within range of enemy shells, and close enough to be seen, but never close enough for shiny bits to be seen unless the sun glinted on them.

[flandersflyer]

The lorries were certainly close enough to be within range of enemy shells, and close enough to be seen, but never close enough for shiny bits to be seen unless the sun glinted on them.

well most of the `heavys` guns would be ranged on known map references...such as jumping off points and ammunition dumps...

these places were often refered to as `windy corner`....and were usually well behind the front line.....

even `TOC H` was well within range of shelling....

TOC H was a rest and refuge from the noise and bombardment of `modern scientific war`..

The tank `Fray Bentos` ( a mark IV male) went on a bit of an odysey around no mans land and the german lines...Fray Bentos held out for 3 days after bogging down....apparantly there were german soldiers crawling over it trying to get in.....

Edited June 1, 2013 by flandersflyer

[Great War truck]

Not really relevant to this thread, but trucks did get shot at and hit:

 

 

 

 

 

[Old Bill]

take a look at the beardmore engine then here:

 

these were fitted to the FE.2b aircraft....which was an artillary flyer/observation aircraft used by the RFC during WW1.

 

to the O/P:

how do you find the general construction & design of the Thornycroft in comparison to the Dennis?

/QUOTE]

 

Hi Glenn.

 

Where is that Beardmore? Looks like a nice bundle of tricks but I wouldn't want to have to keep it clean!

 

The Thorny does not seem to be as refined as the Dennis although there is not a lot in it. They are both true Subsidy lorries and generally very similar.

 

The American lorries are much more distinct. The Autocars are a very nice job indeed with bushes at every wearing surface so refurbishing them was relatively straightforward. They are even bushed for the shackle pins at the non-moving surfaces. The FWD by comparison is quite crude. The casting and machining quality is 'just good enough' and I get the general impression that the engineers did a good job of the transmission and driveline but then lost interest and threw the rest together. It can't be that bad though, as all of them have lasted 90 years.

 

Steve

[flandersflyer]

take a look at the beardmore engine then here:

 

these were fitted to the FE.2b aircraft....which was an artillary flyer/observation aircraft used by the RFC during WW1.

 

to the O/P:

how do you find the general construction & design of the Thornycroft in comparison to the Dennis?

/QUOTE]

 

Hi Glenn.

 

Where is that Beardmore? Looks like a nice bundle of tricks but I wouldn't want to have to keep it clean!

 

The Thorny does not seem to be as refined as the Dennis although there is not a lot in it. They are both true Subsidy lorries and generally very similar.

 

The American lorries are much more distinct. The Autocars are a very nice job indeed with bushes at every wearing surface so refurbishing them was relatively straightforward. They are even bushed for the shackle pins at the non-moving surfaces. The FWD by comparison is quite crude. The casting and machining quality is 'just good enough' and I get the general impression that the engineers did a good job of the transmission and driveline but then lost interest and threw the rest together. It can't be that bad though, as all of them have lasted 90 years.

 

Steve

theres some guys that go under the heading of `the vintage aviator LTD`...their based on new zealand....

they managed to grab the Beardmore from out of a shed in south america where apparantly a couple of FE2.bs ended up after the war...

here:

 

http://thevintageaviator.co.nz/taxonomy/term/199

 

http://thevintageaviator.co.nz/projects/beardmore-engine/beardmore-engine-build

 

http://thevintageaviator.co.nz/projects/mercedes-engine/mercedes-engine-restoration

 

http://thevintageaviator.co.nz/projects/oberursel-engine/oberursel-ur-ii-rotary-engine-build-history

 

i think as the war ground endlessly on the general quality of equipment would`v been `just enough`....take the hispano suiza engine for instance....the french didn`t really have the time to get it reliable.....its a case of how many units can you get to the front...it doesn`t matter if they dont last as the avarage life expectancy of an RFC pilot during `bloody april` was 2 weeks....yes thats 14 days.....

the hispo was a motor with a lot of potential....but it was the wolseley company that got it to run right...then sold it as the wolseley viper

here:

 

 

the germans also had their own problems to contend with....they were using a synthetic oil...but their rotary engines such as the oberursel and particularly the siemens halske didn`t like it...

Edited May 22, 2013 by flandersflyer

[flandersflyer]

anyway....sorry but i run the risk here of hijacking this thread if i`m not careful....

and I (and i am sure others as well) want to see n hear more about the thornycroft....

[Great War truck]

We collected the castings for the new pistons from the Foundry again – our good friends in Bridport – and the results look good! They were quite happy with the patterns despite any misgivings about them that we might have had – but Steve and John there are very helpful and always bend over backwards to help.

 

Included in the photos is one of the original pistons so that you can see what we have to aim at. So machining of those next!

 

 

 

 

[Old Bill]

I am just getting prepared to machine them now, just as Barry described with the draw bar through the headstock of the lathe. I will face both ends and clean up the inside ready for the gudgeon holes to be bored by a friend with a bigger mill. One particular question arises, though, and that is how much clearance should I give them on the diameter? I have asked around and been given figures from 0.005" to 0.010". The bore is 4 5/16" and it is an iron piston. I plan to make the land above the top ring about 0.004" smaller in diameter than the rest of it which will remain parallel.

 

I would value your thoughts please!

 

Cheers!

 

Steve

[David Herbert]

Steve,

 

I have just looked up manuals that I have on engines with roughly the same bore as yours but built rather later. It seems that for iron pistons the 5 thou figure is the one to use. Engines with aluminium pistons used 9 to 10 thou.

 

Can I suggest that you final machine the crown of the piston quite late in the process at the same time as you do the ring groves and outer dia.. It is critical that the distance from the gudgeon pin hole to the crown is the same for each piston so one must be measured from the other. Untill you machine the bottom of the skirt and drill the gudgeon holes you can not hold the piston in the lathe dead square to the lathe axis so you need to do that so that the crown of the piston is square to the axis. If you try to hold the unmachined outer dia in a three jaw chuck, even with the bottom machined, it will be difficult to get it square and you will be squashing the weakest part of the skirt.

 

Good luck

 

David

Edited June 3, 2013 by David Herbert

[Gordon_M]

If anyone is wondering why the difference in the clearances, an Aluminium piston will expand slightly more rising to the same temperature as an iron one would - assuming you are using a cast iron block in both cases.