# Starrett Level Help



## sped35 (Feb 6, 2013)

Please help me answer a dumb question? I have been trying to figure out what the differences are, between the Starrett Mechanics 98-12 and the Precision 98Z-12 levels. I've been checking online and different catalogs. What am I missing here? What is everyone using to set their machines up?


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## joe_m (Feb 6, 2013)

They are the same tool but the Z comes in a fitted wooden box and the other doesn't.


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## Old Iron (Feb 6, 2013)

I use 2 Lufkin 12" levels made by Starrett the same as the 98-12 both are in wood case's.

Paul


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## fastback (Feb 7, 2013)

I am not so sure that that is the complete answer.  I went to the Starrett site they have 4, 98 - 12 levels 2 are with the Z and 2 are with out.  Each one has a different price.  The Z's do have wooden cases but 2 different part numbers.  In reading the specifications they all look the same, unless I am missing something.  

I have and use a 98 - 18 I purchased at an antique shop.  I was able to get it for $75,  I noticed that he vile was not completely filled the bubble was just a bit over sized and made the reading just a little harder.  Since I live in Mass I decided to take a ride to their factory.  Well it ended out costing me around $135. I guess I ended out saving around 100.00 over the cost of a new one.  Oh, my level originally started out as a model 97, that predates the model 98, but with the changes it is now a  98. This level is accurate to .005 per 10-inches.

Another Paul


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## OldMachinist (Feb 7, 2013)

You can get the 98-12 four ways. 98-12 (part #50443)is the just the level, 98-12 w/slc(#66934) is level with letter of certification, 98Z-12 (#50446) is level with wood case and 98Z-12 w/slc(#66933) is level with case and certs.


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## fastback (Feb 7, 2013)

Wow, so that certificate is pretty expensive.  I would think that people that buy this level would expect it to be very accurate which I'm sure they are, but to have to pay extra for a certificate.  Well that sucks.  I guess what I am saying is I could buy a over the pond for less and most of them are rated a.0005.  Don't get me wrong I really like my level and I did get a ticket not certificate indicating it was good for .005 I just think that if it is not certified it maybe should be less.  That's my opinion anyway.  

Paul


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## lotechman (Feb 8, 2013)

I matched up an old Starret precision level with my two foot Stabila digital.  The Stabila is good to tenths of a degree and is what I would call good construction grade in today's world.  From what I could tell by placing a small wire under one end then removing it there was no greater sensitivity between the two.
  I am sure that certifications are important but from a practical point of view there are some really good levels on the market that are very sensitive.  I used the Stabila for my lathes and milling machine and I am happy.


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## OldMachinist (Feb 8, 2013)

For places that have to have all their metrology tools certified to ISO or ANSI specs it can be cheaper to buy a tool with the certs vs having to send out a brand new tool to be certified.


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## fastback (Feb 8, 2013)

Just wondering, do they need to be recertified from time to time?  Is that something that can be done in house or must they be sent out?


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## jmh8743 (Feb 8, 2013)

http://www.ebay.com/itm/26111795164...l?_from=R40&_sacat=0&_nkw=261117951643&_rdc=1

This is an eBay item LOOK at it. look at this and the 10 second bubble radius. I do not see a means to adjust. If it does, then.....

Then look at the starrett. The Starrett:

http://www.starrett.com/metrology/m...urrentPage=1&displayMode=grid&sortBy=none/asc


Basically they used the SAME BUBBLE until they get to the "precision". All their levels on this page are adjustable. This is needed because at some time it will be dropped. I looked a each item on this page.

"_80-90 seconds graduations or .005" per foot (0.42mm per meter)" meaning that it is capable of resolving about 1/2 mm in 1 meter or 0.005" per foot_.

As the price goes up the vial does not change BUT the GROUND lenght does. That is the big ticket. If the surface is long and flat, short is OK. If surface is rough, need long base.

That is UNTIL you get to the PRECISION grade. "_Ground and graduated main vial of 10-second accuracy; one division equals 1/2 thousandth (0.0005) of an inch per foot, or 0.04mm per meter _" Big difference. 3

So, in conclusion, if you want a longer lenght, if will cost. The bubble is the same. MEANING the graduations subtend the same angle of arc.

(Now adjustment is easy. Let me know if you want to know how AND you do not need a perfectly level surface.)

One minute of arc is 1" in 300 feet (about). This is 60 seconds. (really 57") OK?

So assume you need (want, require) 0.010 max error 4 feet away. This is your decision.

1 inch/300 ft = 0.003

.010/4 = 0.0025 <= this is 0.025" per foot.

(0.0025/.003)X60 = 0.8333 X 60 = 50 seconds. SO each readable graduation on the bubble needs to be less than 50" of arc for you to acheive your goal.

for what it's worth and respectfully submitted,


Mike

The guys below have told you what they used. This is the precision of your level.
I paid >$150 for my Bridge City 15 yrs ago. A thin paper strip, 0.003, causes it to move about 1/2 grad. It is only 8" long, but sensitive bubble. I have adjusted mine numerous times over the years.


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## sped35 (Feb 9, 2013)

Thanks for all the replies folks! 
What I was wondering, what is the difference in accuracy if any?


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## jmh8743 (Feb 11, 2013)

Did my revision help?


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## fastback (Feb 12, 2013)

Even after having my Starrett 18-inch rebuilt I needed to reset the vile.  It is relatively easy to do. You flip it end for end and adjust until the readings on the vile are the same.  Level does not need to be perfectly level to make the adjustments, just make sure the reading is the same in both directions.  Even temperature change can affect the readings.


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## rwwells (Feb 12, 2013)

For jmh8743

Hi Mike,

(Now adjustment is easy. Let me know if you want to know how AND you do not need a perfectly level surface.)

I am interested in knowing how, I have an old Lufkin #58 12" long. Especially the part about it doesn't have to be perfectly level.

Thanks,

RWW


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## jmh8743 (Feb 12, 2013)

12" is great. Could you send a photo. With that I can be explicit. Easy button applies. just like fastback says.  
If he can do it, anybody can do it. Hee Hee.


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## sped35 (Feb 12, 2013)

Thanks again for the help fella's


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## rwwells (Feb 13, 2013)

Don't know if I am as smart as Fastback,
here is a picture of a Lufkin 58 12"


Thanks,

RWW


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## fastback (Feb 13, 2013)

So what's up guys?  Why are you coming down on me? What did I do?  The Starrett level is easy to adjust.  You just need to take your time. 

 Oh, I did fine tune my other post.


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## jmh8743 (Feb 14, 2013)

Fastback, nope just a surly comment to RWW. Glad u commented 'cause it seems hard but is not.

RWW: great photo and a great level. I'll have something for u Friday. 
Also I'll give you a method to test sensitivity. 

Mike


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## jmh8743 (Feb 15, 2013)

RWW,

1. find a flat surface, mill table, vice, etc the length of your level. I use my band saw table. A circular saw table OK.

2. set the left end on your left hand. This end is not adjusted, the one with the cross vial.

3. Read the left end of the bubble. The surface must be level enough to be able to read one of the graduations, but flat.

4. Remember the location measured from the hash mark and the direction.

5. Rotate the level 180^. (Now the jams nuts are on the left side. First iteration)

6. slightly loosen the vial case screw on the right.

7. loosen the jam nut on top, now on the left hand.

8. adjust the bottom nut until the bubble takes out HALF the difference. hand tighten jam.

9. RETURN TO 5




Finally, there will be no adjustment.

when satisfied, tighten jam and case screw. You will have to do this several times a year.

Lastly, insert a thick card stock under one end, mine measures .007", and tell me how many graduations and partial graduations this moves the bubble.

Tell me  the thickness of your stock. The length of your vial tells me this will be a great level. Now it is adjusted to read "plumb" as it is called.

Mike
Remlap AL


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## rwwells (Feb 15, 2013)

Thanks so much, very clear and informative.


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