Thread: Can anyone identify these markings?

There is definitely no weight information there, letter "Г" is the part of ГОСТ abbreviation. So "ГОСТ 8026-75" refers to the document.

"кл" is the abbreviation for "класс" - class, category. Definitely not kilograms, they have different abbreviation.

So far reading all those documents, my current guess is that 6 is the type of the straight edge (i.e. shape). "кл 1" is precision, which from general statements I found, mean relative 1% accuracy. At the same time this doesn't sound like really precise.

Means of verification – a straightedge type LD accuracy class 1 according
to GOST 8026-75; feeler with thickness of 0.02 mm and accuracy class 2
according to GOST 882-75.

In the document I am reading if the straight edge is a class 1, and the item being tested is a class 2, if it has a 0.02mm gap it fails to pass as a class 2.

So it would suggest that class 1 would need to be above 0.01mm.

How accurate do you need to be when building a Boeing 744??? I think I need to also look at what similar items are accurate to.

Originally Posted by DSEL74

In the document I am reading if the straight edge is a class 1, and the item being tested is a class 2, if it has a 0.02mm gap it fails to pass as a class 2.

So it would suggest that class 1 would need to be above 0.01mm.

How accurate do you need to be when building a Boeing 744??? I think I need to also look at what similar items are accurate to.

Hi Dale,

0.0001" per 12" (0.01 mm per meter) is ball park for precision cast iron straight edges.. Still need to see what it looks like tho, is it camel back? parallel sided? how long is it?

Ray

IMG_4872.jpg Its 1000mm long

IMG_4873.jpg

IMG_4874.jpg Little light surface rust on the ends which I will have to address soon.

I said it was cast but it may be milled? The centre has flycutter marks, but looks grey under the flaking black coating.

I'm wondering if it's a staight edge(or at at least what "we" call a straight edge)?
It looks way to light. More like the biggest parrallel I've seen....Maybe for set ups on a plate?

Stuart

Hi Dale,

It looks a bit on the thin side as far as the rigidity required in a precision straight edge. Although the Suburban style might not be much deeper? CAST IRON STRAIGHT EDGES by Suburban Tool, Inc.

The working surfaces should be ground, rather than milled.

Ray

it is a lot lighter than the hump backs I have seen and some of the parallels even.

The edges are ground, its the channel down the middle has mill marks under the paint or coating.



Dimensionally it is similar to this one in Rays link but lighter still, 1000mm x 15mm x 60mm

MODEL	LENGTH	WIDTH	HEIGHT	WT(#)	PRICE (US$)
SE-36-CI	36"	1-1/2"	3"	27	$ 741

There are precision straight edges that are thinner than this which look like large blank rulers. What would you guys suggest it is then???

This still would be useful in setting up machines and marking out operations on the surface plate I hope. Or did I waste my money??

Made in USA not USSR 0.0003" over full length.Taft-Peirce STEEL STRAIGHT EDGES by Suburban Tool, Inc.

looks just like it.

MODEL #	LENGTH	WIDTH	HEIGHT	STRAIGHT & PARALLEL	WT (#)	PRICE (US$)
9169-36	36"	3/8"	2-1/2"	0.0003"	9	$ 935

• Made of heat treated alloy steel.
• Edges precision ground, parallel and straight.
• All sizes are proportioned for proper balance between rigidity and weight.
• Sizes 24" and longer have marked support points which should be used to minimize deflection due to gravity.
• When not in use, these straight edges should be hung vertically by the hole provided in one end.

STRAIGHT EDGES
NO. 9169 SERIES

Taft-Peirce Steel Straight Edges provide an extremely accurate reference surface for scribing straight lines and for checking surface straightness and flatness. All sizes are proportioned for proper balance between rigidity and weight. Sizes 36" and longer have marked support points which should be used to minimize deflection due to gravity. Properly supported and cared for, these straight edges will retain their accuracy almost indefinitely. When not in use, they should be hung vertically by the hole provided in one end. Steel Straight Edges may be readily self-checked by inverting them on proper support points and indicating both sides at the center.

SPECIFICATIONS

No. 9169 Steel Straight Edges are made of high quality alloy steel, scientifically heat treated for maximum stability and wear resistance. Edges are precision ground parallel and straight within limits listed in the table below. Orders should specify both Style Number and Length.
Checking the accuracy of a properly supported Steel Straight Edge. One edge is indicated in the center as shown;then the straight edge is turned over and the opposite edge indicated in the same manner.


Screen shot 2014-02-03 at 1.31.46 PM.png

They are for checking straightness on things.... Like engine blocks and other things that need to be flat.... You put feeler gauges underneath or look for light....

Would be handy to have...

Straight edges for scraping purposes are only much heavier because they are 50mm+ wide and need extra support to stop that extra weight from warping....

Just had a 80+ year old engineer turn up to visit, so I thought I'd get his opinion on it. In his opinion it is a straight edge and he had used plenty of that same size and design. He used to have one the same which he used as a master to make smaller straight edges. So that is reassuring.


Still would like to know what the markings are though.

Originally Posted by DSEL74

I had with a Russian Australian girl on facebook, she has no knowledge of tools and measuring…..she is a dancer. Her answers are in bold

I don't suppose we could see a picture of the dancer? R.C's in the market for a good woman.

Just kidding. Phil.