|Austin O'Hara||21/12/2019 14:02:35|
|20 forum posts|
Seasons greeting everyone.
This Compac 532 is advertised on eBay for £45 or best offer by a reputable dealer (He has a returns policy). It is unused. There are no accessories. I intend using it on a Sherline Lathe as an indicator of run out and alignment. Does anyone know what (NOS) in the title means? The photos shows the large needle pointing at 84 while the small needle less than zero. Is this not calibrated correctly?
Long Island Instruments consider the Compac make to be the best. Any feedback gratefully received.
Edited By Austin O'Hara on 21/12/2019 14:15:56
|Brian H||21/12/2019 14:14:21|
1806 forum posts
NOS stands for 'New Old Stock' and means that the item may be old but it has never been used.
It is Swiss made and looks to be a good item.
The position of the large hand is not important as the bezel can be rotated to bring the zero to line up with the hand in whatever position it is in.
£45 seem a reasonable price but it would be worth offering less to try and find out what he will go down to.
|Swarf Maker||21/12/2019 14:15:13|
|100 forum posts|
NOS is an abbreviation for New Old Stock. Got beaten to the answer!
Edited By Swarf Maker on 21/12/2019 14:16:11
|not done it yet||21/12/2019 14:23:20|
|5041 forum posts|
I would say, for me, no.
Vendor is clearly not thinking that - or they would not have had a ‘make an offer’ option, would they?
It is only a 0.01mm resolution instrument - even though a fairly clear and large scale. It may be very accurate - but how many of us use them as absolute measuring instruments?
Epay (with paypal) could swallow up six quid of that amount.
Your choice, as always.
’NOS’ means what it says in the title - New Old Stock.
edit: OK, others were here before me!
Edited By not done it yet on 21/12/2019 14:24:57
6346 forum posts
Be a little careful buying 'New Old Stock' because it might be past it's sell-by date, or have been badly stored. Don't expect Boer War ration packs to be in perfect condition even if they are in their original crates! On the other hand, I've had beautifully packaged WW2 mechanical parts that were good as new inside.
A NOS Compac 532 is unlikely to be an antique - they're still available new. Looks like a reasonable buy.
|Andrew Johnston||21/12/2019 14:59:19|
5675 forum posts
Only the purchaser can decide if the instrument is worth the asking price; there's no absolute scale of value for money.
While it might be a fine instrument it isn't really correct for aligning work on a lathe. Here are two instruments:
The instrument on the left is a dial gauge. It will accurately indicate the movement of the plunger. In the case of the one shown over 3mm by 0.002mm increments. However the plunger needs to be perpendicular to the work. They are normally used in a holder on a surface plate for comparison purposes. The instrument on the right is a dial test indicator (DTI), and is what I use for measuring runout and setting up the 4-jaw chuck on the lathe. Total movement is small, less than 1mm, but the probe can be moved to any angle, relative to the body, that is convenient. While the DTI doesn't give absolute readings it's much more flexible when it comes to setting up work on the lathe.
|Clive Foster||21/12/2019 15:12:21|
|2389 forum posts|
A decent indicator at a reasonable price. But it may well not be best for you.
Its quite large and correspondingly heavy. Needs around 100 - 110 mm of length to operate. Requires a fairly study stand and adjusting arm for easy, reliable use. Short travel, only 10 mm, which should be enough for alignment and runout purposes. Resolution of 0.01 mm is probably fine for use on a Sherline but may well be inadequate if you move up to more accurate machinery. Rest position of needle is below zero by design so everything comes under tension before measurement starts. No backlash then.
Plunger type dial indicators were designed to be used in stands on a surface plate or similar to verify the size of components after manufacture. Usually to see if a production run was in tolerance. Parts would be slipped under one at time and either the reading noted directly or, more usually, the two little sliding tabs on the outside moved to show maximum and minimum tolerances. If the needle was between the tabs the part would be within tolerance. Assening accuracy as a measurement device is a can of worms, generally specifications refer to error in one turn of the main needle.
For alignment checks and setting up work in 4 jaw chucks the lever type is generally better. Verdict is the common generic trade name in the UK, (like Hoover for vacuum cleaners). For example **LINK** is pretty much the same as the one I got nearly 40 years ago. Its a null point indicator, not a measuring device although the scale is pretty close. Basically you tweak things until the needle sits on zero or only twitches slightly. Dial is inch and abit diameter so its compact and light. Easy to get into places and can be held just fine by a basic stand.
If you do go for a Verdict don't buy one with a round body as it will be very old, 1950's at latest. Verdicts last well but eventually the centralising springs loose tension and, for practical purposes it will be toast. Tenth thou reading ones are frustratingly sensitive. I have such but my little 1 thou ( about 0.08 mm) calibrated one is good for within 1/4 thou (0.02 mm) error in practice.
PS Andrew is faster on the keyboard.
Edited By Clive Foster on 21/12/2019 15:13:05
Edited By Clive Foster on 21/12/2019 15:22:14
Edited By Clive Foster on 21/12/2019 15:22:58
Edited By Clive Foster on 21/12/2019 15:23:28
|Michael Gilligan||21/12/2019 15:14:07|
16422 forum posts
That’s fine ... The bezel can be rotated [see the screw at about 1 o’clock] and the small pointer is to count full turns.
It’s one of the best 0.01mm Dial Test Indicators you are likely to see.
If you’re happy with that resolution ... I suggest you make a reasonable offer.
|Michael Gilligan||21/12/2019 15:23:34|
16422 forum posts
The one linked is, of course, the real Verdict version [exactly like mine] with the very desirable pear-shaped tip.
” We invented the pear-shaped stylus point to avoid the co-sine error, inherent with the spherical end. In addition, the Verdict Dial Indicator has the unique and patented design of the coil type worm spiral, reducing friction and loading transfer movement to a minimum. This leaves less room for compound errors as found with the gear type indicators.”
Edited By Michael Gilligan on 21/12/2019 15:29:46
|Tony Pratt 1||21/12/2019 15:50:18|
|1237 forum posts|
I've had 2 Compac clocks, one 2nd hand I just use at home now & a new one which I broke after a couple of months, both excellent & both lever type.
I can't remember the last time I used a dial gauge & would strongly advise you stick to a lever type, Mitutoyo are in my experience a good brand but beware of fakes on Ebay.
|Tony Pratt 1||21/12/2019 17:05:20|
|1237 forum posts|
Can't edit my post above, just need to clarify that what I mean by 'a dial gauge' is 'a plunger type'
|Michael Gilligan||21/12/2019 17:30:03|
16422 forum posts
Back to the original question ...
|Clive Brown 1||21/12/2019 17:42:23|
|508 forum posts|
I'd echo the comments re lever indicators. I have a couple of Verdicts, one old and one "Sunday Best". They both get regular use and I wouldn't be without one or both. OTOH, I can't remember when I last used one of my plunger indicators. For sheer vesatility and convenience the Verdicts beat them hands down.
|Austin O'Hara||21/12/2019 21:33:49|
|20 forum posts|
Many thanks everyone for taking the time to respond.
I now understand that a Lever type is what I need.
I have picked out some of the content from the various replies for the benefit of future users.
1. “Be a little careful buying 'New Old Stock' because it might be past it's sell-by date, or have been badly stored”
2. “While the DTI doesn't give absolute readings it's much more flexible when it comes to setting up work on the lathe.”
3. “Its quite large and correspondingly heavy. Needs around 100 - 110 mm of length to operate. Requires a fairly study stand and adjusting arm for easy, reliable use. Short travel, only 10 mm, which should be enough for alignment and runout purposes.”
4. “For alignment checks and setting up work in 4 jaw chucks the lever type is generally better. Verdict is the common generic trade name in the UK, … Dial is inch and a bit diameter so its compact and light. Easy to get into places and can be held just fine by a basic stand.”
5. “If you do go for a Verdict don't buy one with a round body as it will be very old, 1950's at latest. Verdicts last well but eventually the centralising springs loose tension and, for practical purposes it will be toast.“
|188 forum posts|
That’s it! Get a lever type since getting mine I use the plunger one only once a decade!. They are far more versatile, aided by their compact size and ability to move the lever to convenient positions. You can’t use a plunger type to work in a bore without inconvenient add on parts thus, turning it into a lever type!
698 forum posts
TBH in the workshop you want one of each type.
Re the OP, for a NOS Compac, that looks like decent money.
|Brian G||23/12/2019 08:15:22|
|716 forum posts|
As far as the needle position is concerned, I recently bought a Starrett dial gauge and as well as the usual "Made in America" QA card there was a note explaining that the pointer was deliberately set at 9 o'clock so that there was a quarter turn of pre-load if zero was set at the top. I guess enough people must have asked to make it worth inserting the notes.
|Austin O'Hara||23/12/2019 14:08:23|
|20 forum posts|
Would this Mitutoyo 513-404-10T Dial Test Indicator be suitable?
It sells for £106 on Amazon and is supplied by Mitutoyo.
6346 forum posts
More than suitable, but the word I'd use is 'extravagant'!
What's your reason for wanting a pricey instrument? I own a lever type and a piston type DTI: they're both useful in different circumstances. Neither of mine are expected to be accurate. Instead they are used to compare distances or detect tiny relative movements. For example when centring work in a 4-jaw chuck, the DTI only needs to show there is next to no movement when the work is rotated. For that purpose in my workshop (0.01mm is plenty good enough) the dial doesn't need to be anything special.
My instruments are the inexpensive kind, a piston gauge as sold by ArcEuro for £17, and a lever DTI costing about £30. It's possible to find cheaper, but too cheap is best avoided! The difference between my dials and expensive gauges might include: better accuracy over a wider range (rarely needed in my experience), longer working life (provided you don't drop them), and smoother operation. In my opinion the last is the most useful feature. Inexpensive dials tend to be a little sticky in my experience, so using them needs extra care. In a professional workshop slick reliable instruments are worth having because time is money. Not so obvious what benefit a high-end dial gauge delivers in a home workshop.
My biggest regret buying down to a price wasn't the dials, it was the stand! I bought the simplest magnet base available. It works but sure doesn't make manoeuvring the dial into position easy. Unless money is no object, spend that £107 on a couple of cheaper dials and a stand with more joints in it!
PS. My views on tools are utilitarian. Ignore all of the above if enjoying 'nice' tools is to be part of your hobby and plenty of cash is available. My only objection to buying expensive tools is the money might well be spent more intelligently elsewhere.
|old mart||23/12/2019 17:35:01|
|2007 forum posts|
I have three lever type that get used regularly for checking runout, it doesn't matter what they read in that context. I also have plunger dti's which are intended for exact measurement, especially in conjunction with surface tables, they only get used once in a blue moon. They are intended to be used with the plunger vertical, horizontal use can occasionally cause errors because of friction being greater than the return spring strength.
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