Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

--
Ben Jackson

http://www.ben.com/

Ben Jackson wrote:

Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

If you measure the width of the base and beam at several places it'll
tell you if they are _not_ parallel -- measurements all over the place
will indicate that the edges aren't straight, measurements that trend
from one point to another would indicate a taper. About the only thing
that this won't pick up would be parallel but wavy faces.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Sounds like you need a third square...


"Ben Jackson" wrote in message
...
Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

--
Ben Jackson

http://www.ben.com/

On Tue, 01 Feb 2005 19:45:57 GMT, Tom Gardner wrote:
Sounds like you need a third square...

No, sounds like he needs to scribe a line based on the square, flip
it over, and see if it stays on the line. Repeat with the other
square. One of 'em will describe a "v" instead of one line, when flipped.

Dave Hinz

Instead of "piggyback", put them blade-to-blade on a known gauge plate, then
look for light. If they're both good, and your gauge plate is flat, you'll
get a blackout join. If not, borrow a known good one, and figure out which
(or both) are worn or bent. (Maybe instead of borrow, you could haul yours
down to a shop that has the facilities, and ask as a favor to check them
out)



LLoyd

"Ben Jackson" wrote in message
...
Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

You are just no fun!

"Dave Hinz" wrote in message
...
On Tue, 01 Feb 2005 19:45:57 GMT, Tom Gardner wrote:
Sounds like you need a third square...

No, sounds like he needs to scribe a line based on the square, flip
it over, and see if it stays on the line. Repeat with the other
square. One of 'em will describe a "v" instead of one line, when flipped.

Dave Hinz

Hey! Don't sweat it! File down the one that is bent until it mates with
the straight one.

Bob Swinney
"Lloyd E. Sponenburgh" wrote in message
ink.net...
Instead of "piggyback", put them blade-to-blade on a known gauge plate,
then
look for light. If they're both good, and your gauge plate is flat,
you'll
get a blackout join. If not, borrow a known good one, and figure out
which
(or both) are worn or bent. (Maybe instead of borrow, you could haul
yours
down to a shop that has the facilities, and ask as a favor to check them
out)



LLoyd

"Ben Jackson" wrote in message
...
Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

Ben Jackson wrote:

Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...


If you have access to a surface grinder with precision angle plate then
clamp the short leg of the square to the vertical face of the angle plate
so the long leg is horizontal, and take a cleanup grind (very light) on
the long edge.

If your square is out, that is.

GWE

Ben Jackson wrote:
Ok, this is a stupid question, but are the inside faces of a
machinists
square supposed to be square, or only the outside faces? Or, put
another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got
two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

--
Ben Jackson

http://www.ben.com/

If you've got a name brand square, the edges are supposed to be
parallel AND square with the world, that's why you pay the big bucks
these days for Starrett. There's a number of ways you can check them
out, drawing a line and flipping the square, then drawing another is a
crude way to do it, but effective. Most of the others involve surface
plates, sensitive indicators, surface gauges and/or check squares.
Lautard has a lot on squares in his books, one section details how to
lap a square for correction purposes, another section is about how to
make your own precision square. He also tells how to make a
cylindrical square.

Stan

wrote in message
oups.com...
Lautard has a lot on squares in his books, one section details how to
lap a square for correction purposes, another section is about how to
make your own precision square. He also tells how to make a
cylindrical square.

Stan

Yep. Guy Lautard am my HERO. (non-pro, totally-PRO home shop machinist)

LLoyd

Lloyd E. Sponenburgh wrote:
wrote in message
oups.com...
Lautard has a lot on squares in his books, one section details how to
lap a square for correction purposes, another section is about how to
make your own precision square. He also tells how to make a
cylindrical square.

Stan

Yep. Guy Lautard am my HERO. (non-pro, totally-PRO home shop
machinist)

LLoyd

http://www.lautard.com/

Enjoy (really!)

Ken.

--
http://www.rupert.net/~solar
Return address supplied by 'spammotel'
http://www.spammotel.com

Ben Jackson wrote in
:

Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

Both sides are supposed to be square.


I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

There are different grades of squares. Some are within .000080" (eighty
millionths) and some are only .0008" (eight ten thousandths) and there are
others in between. Now if you have two that are of the .0008" variety, it
would be very possible to see light through them even when brand new. IIRC,
they are classified grade 1-4 or something like that. Then there are master
squares. Of course one of them could be bent or worn, as well.

Dan

"Ben Jackson" wrote in message
...
Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...

--
Ben Jackson

http://www.ben.com/

There's a good article in the most recent HSM on indicators that briefly
describes how to check a square with a simple fixture and a good indicator.

"Grant Erwin" wrote in message
...
snip---


If you have access to a surface grinder with precision angle plate then
clamp the short leg of the square to the vertical face of the angle plate
so the long leg is horizontal, and take a cleanup grind (very light) on
the long edge.

If your square is out, that is.

GWE

That doesn't address the inside of the square, which is just as important as
the outside. Fixing a machinist's square that isn't isn't as simple as it
may appear.

Harold

Why no do it the same way you adjust any other square. Use a GOOD
straight edge. Lay the long edge of the square on the SE and draw an
internal and external line. Flip the square and see where the square
lines up. To open the square lay it on a solid flat surface and use a
hammer to strike the inside corner. (this stretches the metal and opens
the legs some) If you need to close the legs you hit the outer corner.
--
Steve Williams

"Harold and Susan Vordos" wrote in message
...

"Grant Erwin" wrote in message
...
snip---


If you have access to a surface grinder with precision angle plate
then
clamp the short leg of the square to the vertical face of the angle
plate
so the long leg is horizontal, and take a cleanup grind (very light)
on
the long edge.

If your square is out, that is.

GWE

That doesn't address the inside of the square, which is just as
important as
the outside. Fixing a machinist's square that isn't isn't as simple
as it
may appear.

Harold






----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Hi guys..new to the group.
What I would do if I had to check my square.
If you have a known angle plate, place it on a surface plate, set up a
dial indicator and run the indicator down the blade and see how much
"run out" there is on the blade. This can be done inside and out, or
you can send it to the inspection department and let them deal with it.
;-)
Tracy

"Grant Erwin" wrote in message
...
Ben Jackson wrote:

Ok, this is a stupid question, but are the inside faces of a machinists
square supposed to be square, or only the outside faces? Or, put
another
way, are the blade and base faces both parallel?

I've got the old "never take two clocks to sea" problem -- I've got two
squares and I piggyback them and I can see light between the blades.
So now I don't know which one is off...


If you have access to a surface grinder with precision angle plate then
clamp the short leg of the square to the vertical face of the angle plate
so the long leg is horizontal, and take a cleanup grind (very light) on
the long edge.

If your square is out, that is.

GWE

And do not be surprised if the grinder bends the blade
down even with a very light cut and your square is worse than before. Been
there, done that. Jim