Bore Gauges

Services for Plastics, Inc. is the North American full-service distributor of Baty Bore Gauges. The 20+ year alliance between our firms gives you the best possible product and services for your bore measuring needs.

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Dial Bore Gauges

Baty bore gauges are an indicator type gauge used to measure the dimensional variation inside an injection molding or an extruder barrel. However, they may be used wherever there is an inner diameter that has to be reached to measure.

How Does A Bore Gauge Work?

All models work on the proven principle of two diametrically opposed measuring points, one fixed and one moving, plus a spring-loaded centralizing shoe. Don’t waste your time and money on other inferior brands that do not use this proven method.

What A Bore Gauge Will Check?

Dial bore gauges allow rapid and accurate checking of bores for: size, ovality, taper and wear within a deep bore.

When To Use

At any time your equipment is shut down and you want to check barrel for wear. It is recommended to use on a routine maintenance program that provides you with consistent recordings for knowing when barrel wear occurs and when it is time to consider replacing barrel.

Note: To obtain correct bore measurements, the barrel must be clean of all plastic debris and be cool to ambient temperature. Barrels measured at elevated processing temperatures must factor in Linear Coefficient of Thermal Expansion (LCTE) variables.

Preventative And Predictive Maintenance

Instrumental to any predictive and preventative maintenance programs is the use of a bore gauge for barrel bore measurements. Most plastic processing companies have specified within their ISO- or QS- Quality Systems that periodic inspection of barrel bores is required.

By periodically taking wear measurements down the length of the barrel bore, a pattern of wear can be determined. Once the data is recorded, an overall pattern of Mean Time to Failure (MTF) can be projected. This course of action will allow plastics molders to plan and schedule maintenance downtime on a machine before the machine is unable to make quality parts.

For more information regarding how to establish a Preventative or Predictive barrel measurement program, please contact us at 1-800-627-.

Why Choose A Services For Plastics, Inc. Bore Gauge?

Easier and convenient to use, in a word Simplicity. Some bore gauges can be time consuming to setup and to use. The Baty gauge has been specifically designed for ease of use. Typical setup time to measure a barrel bore is less than 5 minutes. Inspection time to fully measure a cylinder and record the data is less than an hour regardless of barrel size. And disassembly and storage of the gauge will happen in less than 5 minutes. In just over an hour per machine you will collect and be able to analyze data on the barrels wear patterns that will determine your repair or replacement options.

Baty Bore Gauge With Dial Indicator

Baty Dial indicators are recognized throughout the world as quality measuring instruments. Measuring equipment, like a production plant, must be continually improved to keep abreast of technological advances.

Benefits

• Reduce lost profits due to worn barrels

• Decrease scrap and increase machine run time

• Simple and easy to operate

• Measure at your convenience

• Bore size to be accurately read from the instrument with the minimum of effort. The fixed end of the anvil piece has pressure fingers on either side of it that assist correct placement in the bore; this reduces the reliance on feel by the user

Specifications And Features

• Accuracy --meets or exceeds all international standards

• High Sensitivity--obtained by accurately machined and highly finished, low friction forms and surfaces

• Special toughened materials for spindle and pinions enhances life and shock resistance

• Enclosed movements for rigidity and ease of maintenance

• Accurate interchangeable parts and unit construction for economical servicing

• Uses highly burnished pivots and bearing surfaces to equal jeweled bearings

• High quality materials used throughout

• No electric or air hookup needed

• 0.” graduation indicator readings

• Built-in centralizer shoe for easy repetitive performance

• Shock protected movements with revolution counter 

• For larger bores, a range of interchangeable extension rods allows a single instrument to measure a wide range of bore sizes

Bore Measuring Techniques That Fail

Telescopic Gauges: How they are used

There are a range of gauges that are used to measure a bore's size, by transferring the internal dimension to a remote measuring tool. They are a direct equivalent of inside calipers and require the user to develop the correct feel to obtain repeatable results. The gauges are locked by twisting the knurled end of the handles, this action is performed to exert a small amount of friction on the telescopic portions of the gauge. Once gently locked to a size slightly larger than the bore, the gauges are inserted at an angle to the bore and slowly brought to align themselves radially, across the hole. This action compresses the two anvils where they remain locked at the bores dimension after being withdrawn. The gauge is then removed and measured with the aid of a micrometer or Vernier caliper.

Small Hole Gauges:  How they are used

They require a slightly different technique, the small hole gauge is initially set smaller than the bore to be measured. It is then inserted into the bore and adjusted by rotating the knurled knob at the base, until light pressure is felt when the gauge is slightly moved in the bore. Measurement is again by external means.

Link to Kuasu

Both Telescopic and Small Hole gauges fail to meet the needs of proper bore measuring because they are difficult to obtain accurate and repeatable measurements and they do not allow for full bore length measuring. They are only capable of measuring one spot at a time and cannot show the user if there exists pattern wear that only a continuous measurement can display.

Baty Bore Gauge Supplied Complete

A Baty bore gauge is supplied complete for comparative measurements of bores falling within its specified capacity, typically 7/8” (22mm) to 6” (153mm). Gauges for measuring even larger bore diameters are available.

Absolute measurements of bore size are possible by setting the bore gauge to size, using a bore of known diameter or measuring the distance between the fixed point and the moving point using a calibrated micrometer. An easy to read dial indicator is mounted at the remote end to measure the axial movement of the measuring head. There is a range of interchangeable anvil pieces (extension rods) that transfer the measuring movement to the dial indicator displaying bore deviation.

Typical Ease Of Operation

Adjust the extension rod as necessary so that the gauge will enter the bore and the dial indicator registers. The two contact points on the spring-loaded shoe "A" and the fixed-point "B" form a 3-point contact which centralizes the gauge in the bore. There is no need to grip the gauge firmly and no attempt should be made to influence its position across the bore, as it will centralize itself in this position.

If the gauge is rocked very slightly backwards and forwards so the points "B" and "C" cross the diameter of the bore, it will be seen that the indicator hand moves to a minimum reading and then returns. This minimum reading indicates the position at which measuring points "B" and "C" are correctly on the diameter of the bore, and all measurement readings are taken from it.

Setting The Bore Gauge For Plus And Minus Readings

If plus and minus readings are required, adjust the extension until the "minimum" reading occurs, roughly midway in the range of the dial indicator. Should the full plunger travel be required in one direction, adjust the extension until the indicator registers just at the beginning or end of its travel according to the direction required. Lock the extension securely with the nut. The indicator with its shroud can be adjusted on the body of the gauge if socket-head clamp screw "H" is loosened. Using this adjustment and the rotatable bezel of the indicator, the hands and main dial can be positioned wherever required within the range of movement.

Simple Checks

To inspect a bore merely for out-of-roundness, taper and other variations of shape, or wear, without using a master, set the indicator to zero at one position in the bore and then take readings at other positions.

Checking Variation To A Known Size

The gauge can be set in a bore of known diameter, preferably a ring gauge of the size to be checked. With care, the gauge can be set by outside micrometers or by slip gauges in a holder. Remember that unlike a bore, micrometers and slip gauges have flat faces, and the setting must therefore be square to these faces.

Bore Gauge Maintenance

Baty bore gauges are manufactured for continuous use, but must still be treated as a fragile quality measuring device. Standard maintenance of the gauge should be performed every 3 months or 1,000 bore measurements. Please do not attempt to disassemble your bore gauge. For repair, maintenance and calibration services, contact Services for Plastics, Inc. at 1-800-627-.

The following routine maintenance is suggested every 3 months:

• Check the extent of flats on shoe contacts

• Clean, polish or turn the balls, whichever is applicable, or replace

• Examine abnormal angular play between shoe and bottom section, replace the shoe

• Examine bell crank for wear or damage on edge of ground face and replace if necessary

• Examine the top plunger for wear and/or damage

• Clean and oil all parts carefully

Replacement Parts

Please do not attempt to disassemble your bore gauge. If a component on your bore gauge wears or breaks, SFP has replacement parts to service and repair. While some components on the gauge are non-serviceable, all components can be replaced at a considerable cost savings over purchasing a new gauge. For information regarding pricing and availability of repair components and service, call SFP at 1-800-627-.

Calibration Period

As per most ISO- or QS- Quality Systems, yearly inspection and calibration of all measuring equipment is necessary. When the time for this inspection occurs, contact SFP at 1-800-627- for quotation of inspection and calibration.

Storage

Your bore gauge was shipped in a special impact resistant wooden case. This is where bore gauge should be kept when not in use. This gauge does not require special environmental storage. Any clean, ambient temperature environment will be satisfactory. Do not the store the gauge where it can come into contact with large amounts of dust or moisture.

Useful Life Span

The Baty precision bore gauge is designed for continuous and repeatable use. With proper care and maintenance of the gauge, it has a useful life that can exceed 10 years.

Take a look at an injection-molded toothbrush holder, a plastic gas can, or the silverware tray in the kitchen cabinet. Notice how the walls of these household items are all relatively uniform? This is one of the fundamental rules of plastic injection molding, and ignoring it can lead to sink, warp, and inaccurate or non-functional parts. Yet the functional requirements of consumer, medical, aerospace, and industrial products often leave designers little consideration for the material flow and fill properties of plastic, both of which are at least partially determined by wall thickness.

To achieve uniform wall thickness, let’s start with the basics:

Start by looking for which attributes are most important to the finished product:

• Does it need chemical or ultraviolet light (UV) resistance?
• Will the plastic be subjected to direct flame, or extreme temperatures?
• How strong must the part be, and will it need to flex under load?
• If color is important, can the plastic be painted, or colorant added to the resin before injection?
• What about opacity? Some plastics have good optical properties, others not so much
• Will the product be used in an electromagnetic environment?

While all of these factors are being weighed, refer back to the website’s section on wall thickness. Obviously, materials only make good candidates if they can be molded to the dimensions and geometry needed for your project, while still meeting their engineering requirements. Once you’re close to selecting a material, give one of our customer service engineers a call. They can either advise you directly, or put you in touch with an expert at one of our material suppliers.

For example, nylon 6/6 flows well, is good for thin-walled parts, and has excellent impact resistance, but you might have rejected it because of its average strength and lack of resistance to heat. Adding glass-fiber filler to the resin not only makes the nylon much stronger, but far more heat resistant. Glass also reduces the chance of sink in thick sections, but may lead to warp in thin areas, depending on material flow during the molding process.

In some cases, you might be directed to a completely different material family:

• Polycarbonate is a common material used in designing optical components, but acrylic is often a better choice on thick parts, as it’s less likely to experience sink, voids, bubbles, and poor part detail.
• Optical-grade liquid silicone rubber (LSR) offers superior light transmission and product clarity, and allows designers to break the rules of thick and thin, even with very fine part features.
• A styrene-like material known as K-Resin is often a good substitute for ABS or polycarbonate in large structural components.
• Liquid crystal polymer (LCP) is another glass-filled material that’s strong but has the ability to “go thin” when needed.

Again, there are hundreds of materials and thousands of ways to adjust, blend, or fine-tune them to produce the desired results.

Clever Tweaks Can Help Strengthen Walls

Even if the right combination of material attributes can’t be found, don’t despair. Some clever edits to part geometry go a long way to alleviate internal stress and potential weakness produced by less than optimal wall thickness. Parts shaped like dumbbells or sewing bobbins are perfect candidates for coring, which eliminates large cross-sections of material similar to removing wedge-shaped slices of an apple, but the strong core is left in place. This is a great way to avoid sink, reduce material usage and make parts lighter but just as strong (possibly stronger). And parts like box lids that have tall, thin walls can be reinforced with gussets, so long as the relative wall thickness of the supporting material follows the 40 to 60 percent rules mentioned previously. This also eliminates the chance of shadowing, which occurs when one section of the part cools down faster than others. 

Sign up for our free Design Cube, which is a physical aid that demonstrates the importance of wall thickness and several other design considerations for injection molding.

Design for Manufacturability Offers Feedback

Once you receive your part quote, be sure to review the accompanying design for manufacturability (DFM) analysis, which provides feedback to improve the moldability of your part. Overly thick or thin areas will be color-coded based on nominal wall thickness, along with recommendations on changes to draft angles. Parting lines, ejector and gate locations, undercuts, side-actions, and the need for hand-loaded inserts are displayed as well. If deemed necessary, a flow analysis can be performed, to analyze pressure points around gate areas, and to identify potential knit lines. As always, feel free to contact us at 877-479- or [ protected] if questions or concerns emerge.

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