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Discussion Starter #1 (Edited)
Suck on it, search police! Ain't no way in hell this question has been asked before! I applaud my originalitah.

Anyways, how much force do you think that the dials produce? Now now, I know that you're wondering why in the hell would I care. The answer is simple: I was entertaining the idea of making aluminum "caps" for the dials but don't want to mess with the motors or the readouts too much. The fact that they are at the center means that they shouldn't have to make much effort (as opposed to being at the tip of the needle), and aluminum details at that size shouldn't be too much of a problem. However... would anyone have an idea?
 

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I think doing detail caps at the hinge of the needles you'll be okay. One way to find out right?
 
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Suck on it, search police! Ain't no way in hell this question has been asked before! I applaud my originalitah.
I'll let you off with a warning......
 
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Discussion Starter #6
it wouldnt affect them much unless you cap the whole needle.
The needle itself won't be capped, just the black cylinder at the center.
 

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Suck on it, search police! Ain't no way in hell this question has been asked before! I applaud my originalitah.

Anyways, how much force do you think that the dials produce? Now now, I know that you're wondering why in the hell would I care. The answer is simple: I was entertaining the idea of making aluminum "caps" for the dials but don't want to mess with the motors or the readouts too much. The fact that they are at the center means that they shouldn't have to make much effort (as opposed to being at the tip of the needle), and aluminum details at that size shouldn't be too much of a problem. However... would anyone have an idea?
Search IS your friend...


www.m5board.com/dial-rotational-mass

;)
 

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Wouldn't it be easier to paint the cap aluminum silver?
lol
 

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I'd just have your local machine shop fabricate a linkage to hook the tach needle to the dyno drum down at the local dyno shop, hook it all up, fire up the motor and give'r'hell...:haha:

Since you are putting the extra mass on the center (pivot point) of the needle, it should not have much effect on the force needed to move the needle. I'm digging back to long-ago engineering classes here, but something about rotational moment of inertia comes to mind.

As far as actually measuring the torque produced, you might be able to with a very sensitive torque wrench, Snap On makes some small wrenches that measure down to 10 in-lb, but they are about $200 and even that is almost certainly too much force.
 

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My guess is it won't be the torque.....but the extra mass.....what gauges are you playing with? If it a slow moving one like your temp or gas
gauges it won't make enough difference to matter.....if it is the tachometer your playing with, the extra mass will probably SLOW down the
response time to a possible unhappy and inaccurate level, (but then you like bouncing off the rev limiter going through the gears anyway) can you give me any more details? (which really means what the heck are thinking
about doing this time?????)


Randy
 

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Discussion Starter #13
My guess is it won't be the torque.....but the extra mass.....what gauges are you playing with?
All five of them or the 2 main ones.

gauges it won't make enough difference to matter.....if it is the tachometer your playing with, the extra mass will probably SLOW down the
response time to a possible unhappy and inaccurate level,
This is why I made this thread. I want to know if it would cause a problem.

(but then you like bouncing off the rev limiter going through the gears anyway)
I do not. Maybe you're thinking of someone else.

can you give me any more details? (which really means what the heck are thinking
about doing this time?????)
Just simple, mechanized aluminum caps to put over the needles. Trying to make the walls as thin as possible to make them as light as possible. And, of course, going with aluminum to not only have them be light, but to match the gauge rings as well. Speaking of gauge rings, did you ever get around to making them out of copper?
 

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I think you should be OK. e60 and e90 M needles have a lot less torque.:)
 

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Since I have experience repairing watches and have worked on gauges like these I'll weigh in. Any reasonable answer needs to take into account the force of the hairspring. The gauges have to surmount this linear, increasing force as the gauge needle swings or increases. Thus an increasing voltage overcomes the increasing return force of the hairspring at higher indicated values for each gauge. The hairsprings are relatively big, similar to old wind-up alarm clocks'. In short, without employing mathematics, you should be fine. Normally, I'd be more worried about imbalance so as not to affect the natural poise of the shaft but in this case I don't recall that the gauges are counterbalanced...so here too I wouldn't worry. These gauges are quite more robust than the delicate gauge of a multimeter for example. Thus a little mass at center of rotation will be negligible for your application. You'll be fine.
 

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Discussion Starter #16
HELL yea leave it to the guys at M5board to come up with the answer to anything!
 

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Diny,
I would still strive to make it as light as possible........try making the cup part out of pvc plastic or even delrin.....and then glue a punched out piece of the thinnest gauge aluminum you can find.....make it pretty and super glue it to the top of the plastic cups.
Can't wait to see this mod........

Randy
 

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Discussion Starter #18
Diny,
I would still strive to make it as light as possible........try making the cup part out of pvc plastic or even delrin.....and then glue a punched out piece of the thinnest gauge aluminum you can find.....make it pretty and super glue it to the top of the plastic cups.
Can't wait to see this mod........

Randy
I'll remove the cluster and take measurements over the weekend. So far, however, I know that the walls of this "cap" will be 1/16 in thickness. I'll do some 3D designs and see if I want them slightly conical in order to match my knobs. Yum!
 

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The answer is this:

It will not change the force required to HOLD the position of the dials, at all. So ZERO impact on the "torque".

It WILL change the dynamic response of the dials- by increasing the rotational mass the dynamic response of the dial will be reduced. (So it would reduce the rate of change of torque)

This assumes these are only 'caps' which are balanced and have no moment arm (ie not the dial indicator/arm, but just the central round cap)
 
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