White Instrument Cluster Dial Group Purchase

Andrew

A2OC Donor
Very nice, but I've never understood why rpm is shown in hundreds rather than thousands - for instance we never say twenty hundred rpm, always two thousand, so why show 20 and not 2?
I am struggling to see your point???

If the needle is pointing at 2 and the scale is x1000 then 2x1000 = 2000 rpm which is correct.

If the needle is pointing at say 1.6 then 1.6 X 1000 = 1600 rpm which is correct.

Andy
 

spike

Well-Known Member
I am struggling to see your point???

If the needle is pointing at 2 and the scale is x1000 then 2x1000 = 2000 rpm which is correct.

If the needle is pointing at say 1.6 then 1.6 X 1000 = 1600 rpm which is correct.

Andy
Andy
If you click to expand the link post in Trevor's mail you'll see the 'custom' rev counter dial is marked 10, 20, 30 etc

Cheers Spike
 

Birchall

Dick Chown Award 2016
I am struggling to see your point???

If the needle is pointing at 2 and the scale is x1000 then 2x1000 = 2000 rpm which is correct.

If the needle is pointing at say 1.6 then 1.6 X 1000 = 1600 rpm which is correct.



Andy
Hi Andy

If you look at the picture you will see that the revs are in hundreds and not thousands as it should be. So 2000 revs is shown as 20 on the dial not 2. I have never seen that before and it looks very strange as Trevor said.

2000 revs should be 2 not 20.
I wouldn’t be buying one if 2000 revs was 20

Steve B
 

audifan

A2OC Donor
The tachometer scale dates back to the early days of steam when engines rotated slowly, as they evolved they rotated faster and 10 was adopted for 1000 rpm and became a "standard" of rpm
 

Andrew

A2OC Donor
Okay, I never clicked the link and thought the comment was on the Tom's picture in post #57. All makes sense now.

Andy
 

timmus

A2OC Donor
Mathematically, of course, it's all the same. However, I also find scales based on '1/min x1000' more elegant than those based on '1/min x100'.

Cheers,

Tom
 

RAB

Technical Specialist 1.2 TDI
The tachometer scale dates back to the early days of steam when engines rotated slowly, as they evolved they rotated faster and 10 was adopted for 1000 rpm and became a "standard" of rpm
I've never seen a tachometer on a reciprocating steam engine. Not necessary because they rotate at a relatively slow rate. Steam turbines are inefficient at low revs and so there would always have been a requirement for a tachometer, particularly for electricity generation.

RAB
 
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