(323) 582-7348
Sunday, May 19, 2013
| Established in 1952 (323) 582-7348 |
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Page: 4680 Sunday, May 19, 2013 |
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Two Ball Plug Gages are frequently used in Go-No Go combinations mounted on a common handle. All Ball Plug Gages are supplied with handles which meet American Gage Design Standards, unless otherwise specified.
Measuring inside diameters, the space between two surfaces and the width of grooves are in the broadest applications for Ball Plug Gages.
The Ball Plug Gage has a unique advantage over conventional inspection methods. Its spherical shape provides a self-centering line of contact that can be inserted into a hole at any angle. The ball will not stick or bind, allowing it to be used to measure bell mouth and taper.
The Ball Plug Gage is excellent for use in confined areas even when the actual hole or groove being measured cannot be seen by the inspector.
A feature buried down in a hole or inside a cavity can often be measured by putting a bend in the stem of the Ball Plug Gage.
The Ball Plug Gage is at its best when used to measure holes which have a constant diameter but are not straight--Piping and Tubing for instance.
A variation of the ball gage concept is to mount the ball on a flexible wire so it can actually go around corners. The ball can be put in the middle of a long wire and pulled in either direction.
By machining two flats on the ball, the Ball Plug Gage can be used to actually measure out-of-round holes.
Ball Plug Gages that have two flats on both members are used to gage the inside spherical surfaces of rod end bearings.
The precision Ball Plug Gage makes a radius gage of unparalleled accuracy. By applying a thin coat of oil-base Prussian Blue to the Ball Plug Gage, it becomes a very effective method for checking spherical and toroidal surfaces. When the blued ball gage is brought into contact with the test part, it will leave a telltale blue mark at the points of contact.
These gages are also widely used to measure the pitch diameter of bearing races, threaded surfaces and of gears.
The location of holes, internal and external grooves and various machined details are other common uses for the Ball Plug Gage.
During our fifty-plus years in the custom ball business, we have produced a vast array of ball gage designs. Call us for unique configurations that will help you do a better inspection job.
| A-Diameter Ball Size |
B-Dimension Stem Length |
C-Dimension Stem Diameter |
Prices |
6 - 10 Pieces | Over 10 Pieces |
| 1 - 5 Pieces | |||||
Under .050" Requires a Special quote
|
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| .050" -
.100" (1.3 mm - 3.81 mm) |
3.0" (76.2 mm) |
0.032" (.813 mm) |
$74.00 double | $66.80 double | $60.32 double |
| $41.00 single | $36.40 single | $33.16 single | |||
| .1001" -
.150" (2.543 mm - 3.81mm) |
3.0" (76.2 mm) |
0.062" (1.59 mm) |
$74.00 double | $66.80 double | $60.32 double |
| $41.00 single | $36.40 single | $33.16 single | |||
| .1501" -
.250" (3.813 mm - 6.35 mm) |
3.0" (76.2 mm) |
0.093" (2.36 mm) |
$74.00 double | $66.80 double | $60.32 double |
| $41.00 single | $36.40 single | $33.16 single | |||
| .2501" -
.375" (6.353 mm - 9.525 mm) |
3.0" (76.2 mm) |
0.125" (3.18 mm) |
$74.00 double | $66.80 double | $60.32 double |
| $41.00 single | $36.40 single | $33.16 single | |||
| .3751" -
.500" (9.528 mm - 12.7 mm) |
3.0" (76.2 mm) |
0.125" (3.18 mm) |
$74.00 double | $66.80 double | $60.32 double |
| $41.00 single | $36.40 single | $33.16 single | |||
| .5001" -
.594" (12.7 mm - 15.09 mm) |
3.0" (76.2 mm) |
0.187" (4.75 mm) |
$75.30 double | $75.30 double | $75.30 double |
| $41.65 single | $41.65 single | $38.65 single | |||
| .5941" -
.750" (15.09 mm - 19.05 mm) |
3.0" (76.2 mm) |
0.187" (4.75 mm) |
$77.26 double | $75.26 double | $75.26 double |
| $42.63 single | $42.63 single | $42.63 single | |||
| .7501V -
1.00" (19.05 mm - 25.4mm) |
3.0" (76.2 mm) |
0.250" (6.35 mm) |
$80.72 double | $78.72 double | $78.72 double |
| $43.36 single | $43.36 single | $43.36 single | |||
| Over 1" Requires a
Special Quote |
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"A" - The standard size tolerance for the ball is + .0001" (+ .00254 mm) The roundness or sphericity of the ball is 25 millionths of an inch (.000635 mm) maximum. The surface finish of the ball is less than 1.5 microinches (38 NM) Ra. Finer Tolerance can be supplied on special order. "B" - The stem length listed is standard, any stem length up to 6" (152.4 mm) will be provided at no additional cost. "C" - The diameter listed is standard, any reasonable diameter will be supplied at no additional cost. FLAT - The dimension of the flat will
be produced to your requirement. The standard tolerance for
the flat is + .002" |
 An A.G.D.S. handle is supplied at no additional cost. ( American Gage Design Standard ) |
| A-Diameter Ball Size |
B-Dimension Stem Length |
C-Dimension Stem Diameter |
Prices
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6 - 10 Pieces |
Over 10 Pieces
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| 1 - 5 Pieces | |||||
| Under .050"
(1.3 mm) Requires a Special Quote |
|||||
| .050" -
.100" (1.3 mm - 3.81 mm) |
3.0" (76.2 mm) |
0.032" (.813 mm) |
$91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | |||
| .1001" -
.150v (2.543 mm - 3.81 mm) |
3.0" (76.2 mm) |
0.062" (1.59 mm) |
$91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | |||
| .1501" -
.250" (3.813 mm - 9.525 mm) |
3.0" (76.2 mm) |
0.093" (2.36 mm) |
$91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | |||
| .2501" -
.375" (6.353 mm - 9.525 mm) |
3.0" (76.2 mm) |
0.125" (3.18 mm) |
$91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | |||
| .3751" -
.500" (9.528 mm - 12.7 mm) |
3.0" (76.2 mm) |
0.125" (3.18 mm) |
$91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | |||
| .5001" -
.594" (12.7 mm - 15.09 mm) |
3.0" (76.2 mm) |
0.187" (4.75 mm) |
$92.30 double | $83.27 double | $75.15 double |
| $50.15 single | $45.64 single | $41.58 single | |||
| .5941" -
.750" (15.09 mm - 19.05 mm) |
3.0" (76.2 mm) |
0.187" (4.75 mm) |
$94.26 double | $80.72 double | $80.72 double |
| $51.13 single | $44.36 single | $44.36 single | |||
| .7501" -
1.00" (19.05 mm - 25.4 mm) |
3.0" (76.2 mm) |
0.250" (6.35 mm) |
$94.26 double | $80.72 double | $80.72 double |
| $51.13 single | $44.36 single | $44.36 single | |||
| Over 1" Requires a Special Quote |
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"A" - The standard size tolerance for the ball is + .0001" (+ .00254 mm) The roundness or sphericity of the ball is 25 millionths of an inch (.000635 mm) maximum. The surface finish of the ball is less than 1.5 microinches (38 NM) Ra.Finer Tolerance can be supplied on special order. "B" - The stem length listed is standard, any stem length up to 6" (152.4 mm) will be provided at no additional cost. "C" - The diameter listed is standard, any reasonable diameter will be supplied at no additional cost. |
 An A.G.D.S. ( American Gauge Design Standard ) handle is supplied at no additional cost. |
FLAT - The dimension of the flat will be
produced to your requirement. The standard tolerance for the flat
is + .002"
(+ .0508 mm) but a closer tolerance can be held for a small
additional charge.
| A-Diameter Ball Size |
B-Dimension Stem Length |
C-Dimension Stem Diameter |
Prices
|
6 - 10 Pieces |
Over 10 Pieces |
| 1 - 5 Pieces | |||||
| Under .050" Requires Special Quote | |||||
| .050" -
.100" (1.3 mm - 3.81 mm) |
3.0" (76.2 mm) |
0.032" (.813 mm) |
$109.00 double | $98.30 double | $88.67 double |
| $ 58.50 single | $ 53.15 single | $48.34 single | |||
| .1001" -
.150" (2.543 mm - 3.81 mm) |
3.0" (76.2 mm) | 0.062" (1.59 mm) | $109.00 double | $98.30 double | $88.67 double |
| $ 58.50 single | $ 53.15 single | $48.34 single | |||
| .1501" -
.250" (3.813 mm - 9.525 mm) |
3.0" (76.2 mm) | 0.093" (2.36 mm) | $109.00 double | $98.30 double | $88.67 double |
| $ 58.50 single | $ 53.15 single | $48.34 single | |||
| .2501" -
.375" (6.353 mm - 9.525 mm) |
3.0" (76.2 mm) | 0.125" (3.18 mm) | $109.00 double | $98.30 double | $88.67 double |
| $ 58.50 single | $ 53.15 single | $48.34 single | |||
| .3751" -
.500" (9.528 mm - 12.7 mm) |
3.0" (76.2 mm) | 0.125" (3.18 mm) | $109.00 double | $98.30 double | $88.67 double |
| $ 58.50 single | $ 53.15 single | $48.34 single | |||
| .5001" -
.594" (12.7 mm - 15.09 mm) |
3.0" (76.2 mm) | 0.187" (4.75 mm) | $110.30 double | $101.24 double | $91.32 double |
| $ 59.15 single | $ 53.74 single | $ 48.86 single | |||
| .5941"-
.750" (15.09 mm - 19.05 mm) |
3.0" (76.2 mm) | 0.187" (4.75 mm) | $112.26 double | $101.24 double | $91.32 double |
| $ 54.62 single | $ 54.62 single | $ 49.66 single | |||
| .7501" -
1.00" (19.05 mm - 25.4 mm) |
3.0" (76.2 mm) | 0.250" (6.35 mm) | $115.72 double | $104.35 double | $94.11 double |
| $ 61.86 single | $ 56.18 single | $ 51.06 single | |||
| Over 1" Requires a special quote |
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 ( Click for a Larger Image ) |
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A Bent Stem Ball Gage is Used to
Measure a "Hard To Get To" Internal Cavity. |
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"A" - The standard size tolerance for the ball is + .0001" ( + .00254 mm ) The roundness or sphericity of the ball is 25 millionths of an inch (.000635 mm) maximum. The surface finish of the ball is less than 1.5 microinches ( 38 NM ) Ra.Finer Tolerance can be supplied on special order. "B" - The stem length listed is standard, any stem length up to 6" ( 152.4 mm ) will be provided at no additional cost. "C" - The diameter listed is standard, any reasonable diameter will be supplied at no additional cost. "D" - The angle of the Bend is held within +2 degrees standard. Finer tolerance will require a special bid. |
| A-Diameter Ball Size | B-Dimension Stem Length |
C-Dimension Stem Diameter |
D-Angle + 2 Degrees |
Prices
|
6 - 10 Pieces | Over 10 Pieces |
| 1 -5 Pieces | ||||||
| Under .050" ( 1.27 mm ) Requires Special Quote |
||||||
| .050" -
.100" (1.3 mm - 2.54 mm) |
3.0" (76.2 mm) |
0.032" (.813 mm) |
+ 2 Degrees | $91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | ||||
| .1001" -
.150" (2.543 mm - 3.81 mm) |
3.0" (76.2 mm) | 0.062" (1.59 mm) | + 2 Degrees | $91.00 double | $82.10 double | $74.09 double |
| $49.50 double | $45.05 single | $41.05 single | ||||
| .1501" -
.250" (3.813 mm - 6.35 mm) |
3.0" (76.2 mm) | 0.093" (2.36 mm) | + 2 Degrees | $91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | ||||
| .2501" -
.375" (6.353 mm - 9.525 mm) |
3.0" (76.2 mm) | 0.125" (3.18 mm) | + 2 Degrees | $91.00 double | $82.10 double | $74.09double |
| $49.50 single | $45.05 single | $41.05 single | ||||
| .3751" -
.500" (9.528 mm - 12.7 mm) |
3.0" (76.2 mm) | 0.125" (3.18 mm) | + 2 Degrees | $91.00 double | $82.10 double | $74.09 double |
| $49.50 single | $45.05 single | $41.05 single | ||||
| .5001" -
.594" (12.7 mm - 15.09 mm) |
3.0" (76.2 mm) | 0.187" (4.75 mm) | + 2 Degrees | $92.30 double | $83.27 double | $75.15 double |
| $50.15 single | $45.64 single | $41.58 single | ||||
| .5941" -
.750" (15.09 mm - 19.05 mm) |
3.0" (76.2 mm) | 0.187" (4.75 mm) | + 2 Degrees | $94.26 double | $85.03 double | $76.73 double |
| $46.52 single | $46.52 single | $42.37 single | ||||
| Over .750" Requires a special quote |
A new form of ball gage is the Balwand™ . This simple straight-forward device is very accurate. It measures the distance or gap between two surfaces.
The Balwand™ consists of a long slender shaft or wand attached to a gage ball. The gage ball has at least one flat surface ground on it. This flat is ground parallel to the shaft. In application, the flatted area on the ball is inserted between the two elements to be measured.
Attempt to rotate the ball. If the ball turns without sticking, then the space between the parts is greater than or equal to the diameter of the ball. If the ball sticks and won't turn freely, then the distance separating the two parts is less than the diameter of the ball. In practice, one of the two surfaces is often a reference datum such as a surface plate or precisely machined jig. The part to be inspected is separated from the reference datum by precision spacers or machined bosses.
The Balwand™ can be used for many tooling
and inspection applications including checking the
flatness of large parts, the position of cores in mold
setting operations, and the final shape of intricate castings or
machined parts. By using two Balwands™ of
the proper diameters, a GO and NO-GO ball gage
can be created. An American Gage Design Standard ( A.G.D.S. )
handle is supplied with each Balwand™ at no additional
cost.
| Part Number |
"A" Diameter +.0001" (.00254 mm) |
"B" Length Standard |
"C" Dia. - Standard |
Prices 1 - 5 Pieces |
| BW- plus exact size of the ball |
.1501" - .250" (3.813 mm - 9.525 mm) |
12" (305 mm) |
0.093" (2.36 mm) |
$91.00 ea. |
| BW- plus exact size of the ball |
.2501" - .375" (6.353 mm - 9.525 mm) |
12"
(305 mm) |
0.125" (3.18 mm) |
$91.00 ea. |
| BW- plus exact size of the ball |
.3751" - .500" (9.528 mm - 12.7 mm) |
12" (305 mm) |
0.125" (3.18 mm) |
$91.00 ea. |
| BW- plus exact size of the ball |
.5001" - .594" (12.7 mm - 15.09 mm) |
12" (305 mm) |
0.187" (4.75 mm) |
$92.30 ea. |
| BW- plus exact size of the ball |
.5941" - .750" (15.09 mm - 19.05 mm) |
12" (305 mm) |
0.187" (4.75 mm) |
$94.26 ea. |
| BW- plus exact size of the ball |
.7501" - 1.00" (19.05 mm - 25.4 mm) |
12" (305 mm) |
0.187" (4.75 mm) |
$94.26 ea. |
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This inexpensive ball kit contains a wide variety of 98 non standard precision balls. It consists of groups of special ball sizes centered around commonly used fractional inch balls ( 14 sizes X 7 balls around each size = 98 ) . These ball sizes reflect the most frequently requested balls for inspection applications. Each group of seven balls contain a standard nominal fractional size ball as well as one each of a +.002", +.001", +.0005", +.0002", and - .001", - .002". |
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Part # BK-14
98 Sizes Very Hard Chrome Steel |
The balls are precision lapped to meet the A.F.B.M.A. standard Grade 25. They are spherical within 25 millionths of an inch (635 nm). The surface finish is below 1.5 micro inches (38.1 nm) Ra and the exact ball size is within + or - .0001" of an inch (.00254 mm).
The balls are manufactured from chrome alloy steel that is hardened to 62 Rockwell C for wear resistance. This material has a thermal coefficient of expansion equal to 6.3 micro inches per inch per degree Fahrenheit or 11.4 micro meters per meter Centigrade. This matches steel gage blocks and is the same as most iron and steel products.
This ball kit includes the 14 most popular fractional inch sizes from 3/32" ( 2.381 mm ) to 1.00" to ( 25.4 mm ), see Summary / Prices Page.
Each of the 14 fractional groups of balls is packaged together in an individual plastic vial. These plastic vials are housed in a very rugged plastic tray. This tray is placed inside a robust steel shipping and storage case. This large steel case is 12 inches wide by 18 inches long by 3 inches deep.
| Part # | Nominal Size | Price | Purchase | |
| BK-14 | Ball Kit | 14 Sizes | $345.15 |  |
| 093-BK | 3/32" | 2.381 mm | $29.97 | |
| 125-BK | 1/8" | 3.175 mm | $29.97 | |
| 156-BK | 5/32" | 3.969 mm | $29.97 | |
| 187-BK | 3/16" | 4.763 mm | $29.97 | |
| 218-BK | 7/32" | 5.556 mm | $29.97 | |
| 250-BK | 1/4" | 6.35 mm | $29.97 | |
| 312-BK | 5/16" | 7.938 mm | $31.15 | |
| 375-BK | 3/8" | 9.525 mm | $31.15 | |
| 437-BK | 7/16" | 11.113 mm | $31.15 | |
| 500-BK | 1/2" | 12.7 mm | $31.15 | |
| 625-BK | 5/8" | 15.875 mm | $31.15 | |
| 750-BK | 3/4" | 19.05 mm | $35.73 | |
| 875-BK | 7/8" | 22.225 mm | $42.77 | |
| 100-BK | 1" | 25.4 mm | $42.77 | |
| SA-OIL-PT | 1 Pint Sapphire Oil | 473.18 ml | $15.00 | |
| SA-OIL-GA | 1 Gallon Sapphire Oil | 3.785 Liters | $52.00 | |
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Sapphire Oil is a used as a
lubricant when Ball Sizing. For heavy upsets or when
a better finish is required, this highly chlorinated
oil or wax is the best choice. It is about a forty
weight oil that is easily applied to any bore.
See: Balls for Ball Sizing Also: Report on Ball Sizing |
| Part # | Description | Price | Purchase |
| SA-OIL-PT | SAPPHIRE OIL, PINT | $15.00 | |
| SA-OIL-GA | SAPPHIRE OIL, GALLON | $52.00 | |
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There are two general designs of flexible ball gages. The first and by far the most common flexible ball gauge is a precise ball of the desired size with a length of piano wire glued into a close fitting hole that has been drilled into the ball by the Electrical Discharge Machining process. The flexible wire can be any desired length. This design will obviously be equally flexible in all directions. This is the least expensive approach. The second design has the gage ball fixed to a thin flat reed of spring steel. The characteristic that sets this design apart is that the position of the ball is extremely flexible in one plane and perfectly rigid in a plane 90 degrees to that. In this way, the ball can be guided between the gap to be measured without any binding. This is a much better design for long flexures. |
The ball can be attached in several ways. On larger balls the narrow slot can be machined into the ball using a wire E.D.M. machine and the ball is glued on with high strength epoxy glue. An alternative is to drill a hole in the ball and glue it onto a cylindrical pin that is then slotted with the wire E.D.M. machine. Then, this is glued on the flat spring steel reed. We stock flat flexures in ¼ inch (6.4 mm) and ¾ inch (19 mm) widths that are 0.012 inch (0.3 mm) thick.
With all of the extra work involved in this design, it is obviously a more expensive product.
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Producing one of a kind or small quantities of spherical gage tips by conventional machining is a difficult and expensive proposition. Setting up a machine to produce a high quality tiny thread against a shoulder is challenging. It is desirable to have the thread made of a hard stiff material, but machining such a material straight, concentric, and with a good thread forms in a tiny #4-40 or #2-56 thread is an expensive proposition. The solution is simple, and it's inexpensive. By drilling a small concentric hole in a hard steel or tungsten carbide ball by Electrical Discharge Machining ( EDM) and gluing in a length of high quality rolled threaded stock, the problem is solved. To further enhance the design, a precision nut is added on the top of the ball. If required, a cylindrical spacer can be inserted between the top of the ball and the nut. The design is quite rugged, as the epoxy glue used in the assembly is a ceramic filled material, with a shear strength of 3000 pounds per square inch. |
In addition, the axial load developed by screwing the tip onto the gage is applied between the nut and the thread, but not in the glue joint between the ball and the thread.
The measuring force is 100% compressive stress, so there is no tendency to pull the assembly apart in every day use.
The average cost of a ball gage tip is $36.00.
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Internal threads are a difficult feature to measure. Thread plug gages are expensive and when special pitch diameter gages are required the delivery of the gage can be measured in weeks. Special pitch diameters are required when preparing internal threads for plating, hard anodizing or dry film lubricant and for installing threaded inserts. |
Precision balls of the same diameter as the best wire size for the thread being measured can be used with cylindrical plug gages to accurately measure the pitch diameter of internal threads.
Petroleum jelly can be mixed with the smaller diameter balls to hold them in the pitch diameter of the thread. and anhydrous lanolin can used to hold the larger diameter balls in place.
A good number of balls should be applied all the way around the thread. For most common threads the balls used are very small in diameter and quite inexpensive.
The evaluation of the pitch diameter is made by inserting a progressively larger series of cylindrical plug gages into the gap between the pitch diameter of the thread and the opposite side of the balls.
A point will be reached when one cylindrical plug gage will slip right through the gap but the next larger plug will not even start.
Using this method the pitch diameter of quality threads can be determined within .0002 of an inch.
This method is a little messy but it is safe, it is inexpensive, it is very accurate, and most of the best wire size balls can be supplied directly from stock.
Another excellent application of this technique is to determine the exact positional location of the pitch diameter of a threaded hole. The same basic technique is used but the largest cylindrical plug gage to fit is left protruding from the hole. This cylindrical plug gage will define the true axis of the thread including the squareness. Its position is then determined by a coordinate measuring machine, micrometer, calipers or with a height gage on a surface plate (see Figure 2.).
To prevent the cylindrical plug gage from slipping all the way through a threaded hole in the test part, place an "o" ring around the plug gage about 3/8 of an inch (9.53 mm) from the end (see Fig. 2).
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The balls on this gage set range from 2.0 mm ( 0.07874" ) to 3.4 mm ( 0.1260" ) in increments on 0.1 mm. They are used by an auto manufacturer to check the fit of auto doors. These gages are also referred to as "Gap Gages", "Gap Gauges", "Para-check gages" or "Parallel Checking Ball Gage." Each gage with a stem costs $41.00. |
 Snake Ball |
If you need a black and white, go-no go system for evaluating the inside diameter of any tubing, try a “SnakeBall”©. By coupling a cable or wire to a very hard alloy steel ball that is precision lapped to the precise minimum diameter of the tube, a go no-go situation is created. To prevent the gage ball from getting stuck somewhere in the tube, there is a coil of wire or cable on each side of the ball that is longer than the length of the tube. Using this approach, the ball can be pulled into the tube; and then pulled back out if the tube is undersized or dented somewhere along the path. A cable with a colored plastic coating, can be supplied that will identify different diameters of ball. Frequently the no-go gage, will be a simple standard ball plug gage on an AGS handle, (see ball plug gages). |
By applying the end of a given spherical tipped probe, also known as a ball scribe, across a flaw in a machined or ground surface, the proportions of individual imperfections can be evaluated.
The evaluation is conducted by mechanically scanning across the flaw with a hand held probe. If the spherical tip penetrates the flaw by any appreciable amount, a very evident click will be felt. If the radius of a given spherical tip does not penetrate the flaw, but instead spans it, there will be no noticeable click and the part is acceptable.
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If the spherical tip drops into a flaw,
the probe will move up and down, and a distinct click will be felt. |
If the spherical tip spans the flaw,
no click will be felt. |
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Pencil Ball Gage, Used for Flaw
Evaluation
|
Trade Show Demonstration of the
Sensitive Feel
when Using the Ball Scribe |
The conventional spherical probe diameters are 0.020
inch, which is 0.5 mm, or 0.04 inch, which is one mm
diameter, and 1/16 inch, which is one and one half
millimeter diameter, but somewhat smaller and much larger
spheres are also being used. Other common diameters used are:
English Diameter | Metric |
| 0.150" | 0.00059 mm |
| 0.20" | 0.0078 mm |
| 0.320" | 0.00126 mm |
| 0.050" | 0.00197 mm |
| 0.6250" | 0.00246 mm |
It is of great significance that it is the spherical radius of the test probe that is used, as the sensor element, so that the initial contact surface is only one half the spherical diameter. Then only a small cord of the spherical radius senses the void that constitutes the flaw, so the overall sensitivity of this system is many times greater than might be expected.
The useful life of these test probes is greatly enhanced by supplying the spheres made with tungsten carbide material. This cermet is very hard with a wear resistance that is 30 times that of hard steel.
Because of their small diameter, it is important that the balls be tenaciously attached to the probe handle so they will not be picked off. This attachment is best accomplished by brazing the ball, in place, on the probe tip. Although this task on such small balls would normally be considered impossible, we have mastered the technology to accomplish it. The probe itself is made of highly corrosive resistant metal that can be polished for clean room compatibility.
These flaw evaluation tools may be used to test chips, cracks, dents, dings, nicks, scratches, as well as scars, scrapes and chatter. These gages may be used for chip evaluation, crack evaluation, dent evaluation, ding evaluation, gouge evaluation, nick evaluation, indentation evaluation, scar evaluation, scrape evaluation, and shatter evaluation. This technique has been in use since at least the 1940's. This viable and economical non-destructive testing method can detect surface discontinuities and fatigue cracks that the naked human eye is not sensitive enough to see. Early detection of fatigue can prevent costly teardowns.
It is much less expensive and better suited to field work than a laser evaluation system.
These items are made to order. Price and delivery will be quoted.
