Guess the gauge!

[Andy 308GTB]

I haven't a clue what these are off.
The Smith's tachometers are interesting because one goes clockwise the other goes anti-clockwise.
None of them have any information on the back barring the odd patent number.

Any suggestions gratefully received...

[matchmaker]

The last one I'd suggest is from a tractor or similar - note the engine rev counter for number of revolutions.

[2 sMoKiN bArReLs]

I wonder if the rev counters are from a plane with two engines?

[gforceg]

They seem like a mixed lot. I agree about twin engines (maybe a boat?) for the rev counters but how about this for the small guage in the last picture?

http://www.rototherm.co.uk/company/history.asp

https://www.bonhams.com/auctions/19288/lot/19/

The middle pictures suggests ARIC of Morden Surrey.

https://www.gracesguide.co.uk/Accurate_Recording_I...

Edited by gforceg on Wednesday 27th January 16:23

Edited by gforceg on Wednesday 27th January 16:24

[mfmman]

Andy 308GTB said:

I haven't a clue what these are off.
The Smith's tachometers are interesting because one goes clockwise the other goes anti-clockwise.
None of them have any information on the back barring the odd patent number.

Any suggestions gratefully received...

Those ones look like suction pressure side guages from a refrigeration system

[a8hex]

mfmman said:

Andy 308GTB said:

I haven't a clue what these are off.
The Smith's tachometers are interesting because one goes clockwise the other goes anti-clockwise.
None of them have any information on the back barring the odd patent number.

Any suggestions gratefully received...

Those ones look like suction pressure side guages from a refrigeration system

Or vacuum/pressure gauges from a trains brake system.
As the the rev counters might be from a plane I'd wondered whether these might also be and are measure manifold pressure but the pressure is far too high, even a Merlin 133 was only 25psi.

[john2443]

matchmaker said:

The last one I'd suggest is from a tractor or similar - note the engine rev counter for number of revolutions.

Wouldn't a tractor have Hours rather than revs - I'd have though ship was more likely??

[Andy 308GTB]

Yes, the small temperatue gauge is made by 'The British Rototherm Co. Ltd London'

The vacuum gauges are ARIC Morden Surrey - I guess R could stand for refridgeration (Edit... it doesn't)
Accurate Recording Instrument Co

Interesting re aircraft and tractor ideas

Edited by Andy 308GTB on Wednesday 27th January 16:42

Edited by Andy 308GTB on Wednesday 27th January 16:53

[matchmaker]

a8hex said:

mfmman said:

Andy 308GTB said:

I haven't a clue what these are off.
The Smith's tachometers are interesting because one goes clockwise the other goes anti-clockwise.
None of them have any information on the back barring the odd patent number.

Any suggestions gratefully received...

Those ones look like suction pressure side guages from a refrigeration system

Or vacuum/pressure gauges from a trains brake system.
As the the rev counters might be from a plane I'd wondered whether these might also be and are measure manifold pressure but the pressure is far too high, even a Merlin 133 was only 25psi.

They don't look as if they come from a train. These are normally duplex gauges.

[Andy 308GTB]

So by all accounts that aren't from a car.

[9xxNick]

4,000 rpm would be very fast for an aircraft engine driving a propeller.

However, they might be for (contra-rotating?) engines driving the twin propellers of a boat, in which case the symmetry of the needle position might be advantageous.

[oakdale]

Why would contra rotating engines need contra rotating tachometers?
It would make it harder to observe engine speeds and the balance between the two.

[bangerhoarder]

I’d put money on the last one being aircraft or for another application with an aircraft engine. Measuring revolutions rather than hours is more unusual. 1940s-1950s?

Tractors didn’t have rev counters commonly at that time - only a petrol tractor would rev anywhere near high enough to require that scale but. It just doesn’t fit at all.

[a8hex]

oakdale said:

Why would contra rotating engines need contra rotating tachometers?
It would make it harder to observe engine speeds and the balance between the two.

Are they mechanical rev counters or electric ones?
If they are mechanical then the pair either need to be the mirror image you see here or one needs a gearbox to turn it around. Jaguar XK120 & 140 (plus C & D types) use a mechanical drive direct to the rev counter from a cam shaft and so it turns counter clockwise. The XK150 had a gearbox on the back the inlet cam to provide the drive for a clockwise tacho on the early cars, later ones switched to using a generator and an electric gauge, but that's far to modern by half.

[Andy 308GTB]

a8hex said:

oakdale said:

Why would contra rotating engines need contra rotating tachometers?
It would make it harder to observe engine speeds and the balance between the two.

Are they mechanical rev counters or electric ones?
If they are mechanical then the pair either need to be the mirror image you see here or one needs a gearbox to turn it around. Jaguar XK120 & 140 (plus C & D types) use a mechanical drive direct to the rev counter from a cam shaft and so it turns counter clockwise. The XK150 had a gearbox on the back the inlet cam to provide the drive for a clockwise tacho on the early cars, later ones switched to using a generator and an electric gauge, but that's far to modern by half.

They are mechanical and the rotation of the dials is direct to the drive, if that makes sense.
i.e. one takes an anti-clockwise drive and the other a clockwise drive.

[a8hex]

Andy 308GTB said:

a8hex said:

oakdale said:

Why would contra rotating engines need contra rotating tachometers?
It would make it harder to observe engine speeds and the balance between the two.

Are they mechanical rev counters or electric ones?
If they are mechanical then the pair either need to be the mirror image you see here or one needs a gearbox to turn it around. Jaguar XK120 & 140 (plus C & D types) use a mechanical drive direct to the rev counter from a cam shaft and so it turns counter clockwise. The XK150 had a gearbox on the back the inlet cam to provide the drive for a clockwise tacho on the early cars, later ones switched to using a generator and an electric gauge, but that's far to modern by half.

They are mechanical and the rotation of the dials is direct to the drive, if that makes sense.
i.e. one takes an anti-clockwise drive and the other a clockwise drive.

Thought they must be, they look old enough. So a pair of contra rotating engines would make sense.

[Andy 308GTB]

a8hex said:

Andy 308GTB said:

a8hex said:

oakdale said:

Why would contra rotating engines need contra rotating tachometers?
It would make it harder to observe engine speeds and the balance between the two.

Are they mechanical rev counters or electric ones?
If they are mechanical then the pair either need to be the mirror image you see here or one needs a gearbox to turn it around. Jaguar XK120 & 140 (plus C & D types) use a mechanical drive direct to the rev counter from a cam shaft and so it turns counter clockwise. The XK150 had a gearbox on the back the inlet cam to provide the drive for a clockwise tacho on the early cars, later ones switched to using a generator and an electric gauge, but that's far to modern by half.

They are mechanical and the rotation of the dials is direct to the drive, if that makes sense.
i.e. one takes an anti-clockwise drive and the other a clockwise drive.

Thought they must be, they look old enough. So a pair of contra rotating engines would make sense.

So boat or aircraft - anyone got an idea on the age?

[9xxNick]

Can't help with the age, but I was wondering if the last rev counter might be for an electric motor, where the number of revolutions could be relevant to the servicing schedule for its consumables.

[a8hex]

Andy 308GTB said:

So boat or aircraft - anyone got an idea on the age?

The logo is Smiths M.A., the XK120 gauges just have Smiths. The pre-war SS100 gauges say SS, so that doesn't help.

A thought that has just occurred to me about an aircraft, would they have a mechanical rev counter driver from wing mounted engine all the way to the cockpit? The only twin contra-rotating engined plane I can think of is the P.38 Lightning but then I'm no expert about planes and I've even less idea when it comes to boats.

Edited by a8hex on Wednesday 27th January 22:09

[friederich]

Andy 308GTB said:

I haven't a clue what these are off.
The Smith's tachometers are interesting because one goes clockwise the other goes anti-clockwise.
None of them have any information on the back barring the odd patent number.

Any suggestions gratefully received...

Can't help with what they are from, but they have the characteristic look of A.T. gauges fitted to Bentleys and Rolls Royces in the '20s and '30s - floating pointers from the outside of the magnetically driven drum and red pointers of a particular style.

|https://thumbsnap.com/yot2AG1P[/url]

A bit of googling shows that A.T. were bought out by Smiths, and latterly A.T. gauges were branded as Smiths. They were proprietary gauges, so could have been fitted to anything automotive, aeronautical or industrial - likely post WW2:

http://velobanjogent.blogspot.com/2014/11/the-at-i...