[cwm9]

I'm a newb, so forgive my ignorance please!

I purchased a Brown & Sharpe BesTest 7033-5 .00005 indicator, but it did not come with an instruction manual.

1st question: If anyone happens to have the instruction manual for any B&S indicator, would you mind scanning it and posting it for me please? I can't find even one for any model anywhere.

2nd question: Is the point position supposed to be adjustable?

3rd question: Being a fooling newb, while tramming my mill I ran the tip of the indicator into the table. Thankfully, the indicator wasn't mounted very tightly and rotated in the vice. The indicator appears to still work just fine: smooth, no jumps, quick response: despite this, might I have damaged it? Put another way, can I still trust it?

Thanks!

[easymike29]

This is not necessarily your indicator but it is representative of the species in general. Notice how the lever arm can be rotated approximately 240 degrees.
Gene

[cwm9]

Thanks. Do you just turn the large black screw to loosen the lever? I tried turning it but it seemed to be very tightly set and I didn't want to damage the unit.

[easymike29]

No, the lever will move, with some resistance, with finger pressure. It's a friction fit. It's scary the first time you try. Be sure that the lever, or point as we call it, is firmly screwed in to the pivot. Don't over tighten as the threads are tiny.
Gene

[cwm9]

Wow, you totally made my day, THANK YOU! Now I know I didn't damage my indicator AND I know how to adjust it... =) =) =)

[easymike29]

cwm9
Thank you for letting us know the results of the information you received here. We are often left not knowing whether the poster benefited by our suggestions. Responses such as yours makes it all worth while.
Gene

[juergenwt]

cwm9 - do yourself a favor and use a .001 indicator on your mill.
.00005 will drive you nuts. Juergen

[Astonlee]

Yes the sylus are adjustable, but when measuring, make sure that measuring axis stands perpendicular to the measuring direction. If this is not possible, the taken measuring value must be multiplied with a correction factor, which is dependant on the angle a. For angles under 15° the correction factor can be neglected.
Angle a 15° 30° 45° 60°
Correction factor 0,69 0,87 0,7 0,5

[ImanCarrot]

An involute tip will correct for this cosine error (up to a certain point!). The tip is shaped like an almond instead of a sphere.

[Astonlee]

Comments involute tip, are correct for reducing the cosine error within 30°, but general a lot of engineers have never consider this error when they using lever/finger clocks in the workshop.

[ImanCarrot]

Yep, probably over the top for general machining, sorry, should have said that, but I'm centering stuff to 1um

[juergenwt]

Am I reading this right? You are centering stuff to within 1µ = 0.001mm = 0.00004"?
If you can do it - my hat is off to you!

[ImanCarrot]

Ayup 1 micron. (1E-6m), a thousandth of a millimeter.

Actualy I centre up to 0.2 microns using a Federal Gauge which is the realistic resolution of the gague, but I say 1 micron in case environmental considerations cause bad things to happen hehe (like if the lab temperature is 18 deg C, not 20).

I use a cotton bud to tap the component on its edge then whack the vacuum up to hold it.

I make sure the lens surface matches the glass chuck by viewing it under monochromatic light- you can see fringes (Newtons Rings) and that lets you know it's edge contact by the way the fringes move as you press the lens. I go for a couple of fringes edge contact, if it was centre contact then the lens would "rock" about it's axis and the centration (parrallelism) would be out.

Depending on whether it's centre or edge contact the fringes will move inwards or outwards. Oh, we're talking wavelengths of light here. Like 1 wavelength of HeNe (red) light is about 633 nm (0.6 microns). Actualy it's 632.8, but everyone says 633.

The most accurate thing I've made is a flat glass (actualy, it was Zerodur, a glass ceramic with almost zero thermal co-efficient of expansion) test plate, 12" dia and one twentieth of a wavelength of light peak to valley across the whole apperture (at lambda= 544nm). I made this by hand using the same techniques that Newton used years ago. Pity that no one knows how to do it these days, wish I could pass the knowledge on to someone *sigh*

[EditForgot to say... I could make more accurate if it was measurable, but after about a twentieth of a wavelength light starts to diffract and act weird...like a particle instead of a wave or something. Dun matter, as an engineer all I need to know is that 1/20th lambda is diffraction limited. [/Edit]

It's a bit of a fine art, and hence my sig line lol.

[juergenwt]

My hat is off to you!! I hope you can find someone to pass your know how to.
Juergen

[Astonlee]

I am really sorry to say this, but it is accepted metrology practise that your measurement instrument needs to have accuracy/resolution 10 times higher than the measurement value you need to check.
Bearing mind you are using an indicator, their no way on god earth can you measure 1 micron, your parallax error alone can be more than half a micron, let alone the rack & all the gears etc in the indicator, hence why they are called “Indicators“.
If you really do need to be chasing a “micron“, you really need to up the anti with your measurement kit, otherwise you are just kidding yourself.

[ImanCarrot]

Ah, I may have not explained clearly.

I use a Federal Gauge, not your standard dial test indicator although it's the same principle. It can easily measure sub micron: no problem. I also use a Talysurf which is more than capable of sub micron, as are my two LVDT probes.

These are specialised high accuracy gagues though, not your standard dial test indicator. Apologies for the confusion!

[Astonlee]

Sorry I thought this thread was about using dial indicators, hence my comments and the miss-understanding!

[ImanCarrot]

No problem, it was me that went off at a tangent. I blame the 8 pages of polynomial mathematics I had to do, combined with sub- contractors phoning every 10 minutes and an MD that wants everything cheap, fast and correct lol

[cwm9]

Am I reading this right? You are centering stuff to within 1µ = 0.001mm = 0.00004"?
If you can do it - my hat is off to you!

There's a tool for everything, but I'm not sure I'd choose a .00005" indicator for that job! Lasers maybe?

I wasn't trying to get it vertical to within 1 micrometer over 3 inches, mind you -- that would be silly. My 123 block isn't that accurate to begin with, let alone the Taig table. Nor do I have any need for such accuracy. Yet, I was able to get it trammed so the needle moved no more than .0004" over a span of 3 inches without much effort. Combine that with the 123 blocks .0002 rating, and that's around .0005 over 3 inches, plenty good for my junk projects.

Using a .00005 made it very easy to see what was going on from far away because the needle moves a LOT with just a little error. It wasn't hard at all to use.

[mc-motorsports]

There's a tool for everything, but I'm not sure I'd choose a .00005" indicator for that job! Lasers maybe?

I wasn't trying to get it vertical to within 1 micrometer over 3 inches, mind you -- that would be silly. My 123 block isn't that accurate to begin with, let alone the Taig table. Nor do I have any need for such accuracy. Yet, I was able to get it trammed so the needle moved no more than .0004" over a span of 3 inches without much effort. Combine that with the 123 blocks .0002 rating, and that's around .0005 over 3 inches, plenty good for my junk projects.

Using a .00005 made it very easy to see what was going on from far away because the needle moves a LOT with just a little error. It wasn't hard at all to use.

Can I ask why you use a 123 block to tram your spindle? Why not just sweep the table? More than one way to skin a cat, just wondering.