We charge sales tax to New York State companies unless a tax exempt form is supplied at time of order.
We ship via UPS and Federal Express on our account or UPS, Federal Express, or DHL on our customers' account. Certain items with pallets, additional weight and oversized require cargo delivery.
Yes - we are experts at shipping throughout the world. We ship to all countries permitted by the United States Department of State.
Ex Works (EXW) is an international trade term that describes an agreement in which the seller is required to make goods ready for pickup at their factory.
No - we accept wire transfers, ACH payment, and credit cards.
Yes - DUNS #063262642
Yes. Thread Check's accredited certification can be found on the website. Click Here
Thread Check is a proud member of the AMTMA. The American Measuring Tool Manufacturers Association (AMTMA) stands for serving, supporting, and educating American precision tool manufacturers and their pursuit of competitiveness in world markets.
Yes - our Cage /NCAGE is #6NGK6.
Yes - we are registered and listed with SAM.
Yes - Thread Check is registered with ARIBA and can work efficiently with your procurement department receiving purchase orders, invoicing, and payments.
No - shipping costs are additional and can be requested at time of quote or order. Taxes and import duties are the responsibility of the receiver. You must contact your freight forwarded or shipping company for this information.
We accept Visa, Master Card, American Express and Discover.
As many of our orders require special processing requirements including special gage sizes, tooling, gage blanks, custom marking and other specific customer requirements, it is company policy that we charge your credit card at time of order. In the event of a Cancellation, charges will be incurred for the portion of the order or service completed and a credit will be issued. Alternate payment arrangements may be discussed with your sales agent.
A net 30 credit application package can be requested by contacting us via email, phone or fax. Credit application processing may take up to 5 days.
Thread Check, Inc. warrants all gages for 30 days from date of shipment if found not to be in tolerance except in cases of customer mishandling. Special gages including special marking are not returnable. Thread Check, Inc. offers no further warranties, expressed or implied and its responsibilities, due to any defects or inaccuracies of the gage or certificate, shall in no event nor for any cause whatsoever exceed the purchase price of the gage.
A LFC is the acronym for Long Form Calibration. An LFC provides the critical measurements for a specific gage documented and supplied with your order.
Yes- all gages are traceable to NIST unless noted.
Our corporate office is located at 900 Marconi Ave, Ronkonkoma, NY 11779 USA.
Protecting gages from excessive heat, humidity, moisture and corrosive chemicals will extend the life of your gages. After use, gages should be cleaned and recoated with a thin-film rust preventative or dipped in an easy to peel oil-based waxed coating, and stored properly in a controlled gage crib or controlled area. Click here for technical document.
A blunt point on a thread plug gage is the removal of a male center point from threads smaller than #6 (M4). This does not allow the gage to be face ground to within .5P. This is not a Blunt Start.
A chamfer on a thread plug gage is an angle ground on the front of a gage that allows for easier assembly with the mating part.
Convolution on a thread plug gage is the removal of the incomplete thread back to the first full thread. Convolution is also known as a "Higbee Cut" or "Blunt Start" per ASME B1.7 - 2006.
Measure from the centerline of the first full thread to the flat step of the notch. A depth notch is only used on a go plug gage and is used to measure thread depth.
Grind the face of the thread plug gage w/in .5P - A convoluted thread plugs face is ground back to the base of the first full thread. This permits the gage to inspect a blind hole down to the bottom of the thread.
UN Bolt (external) is compatible with a UN Nut (internal
UNJ Bolt (external) is compatible with a UNJ Nut (internal)
UN Bolt (external) will fit into UNJ Nut (internal) but functional problems may occur. The two threads are not designed to be used as an assembly connection. There are dimensional differences in the threads which may create issues in extreme cases. Dimensional differences related to shape and thread minor diameter may impact the strength of the material including stress cracking and loading failure. The above factors are product design related and impossible to determine without conducting an extensive testing and evaluation of the design.
UNJ Bolt (external) in most cases will not fit into UN Nut (internal) as there may be minor diameter interference and functional assembly issues
STI or Screw Thread Insert, Helical Coil, or Heli-Coil are names or trade names synonymous with STI threads. STI threads are used to repair stripped or poorly threaded holes. STI thread plug gages are used to check the threaded hole prior to installing the threaded insert.
This is called a chip groove which is an angular or straight groove cut from the first thread back. This is found on go thread plug gages over #8 (#8 or smaller do not have a chip groove). The chip groove is used to remove small chips and matter from the threaded part.
A thread ring gage that has been set to the factory setplug and then the set screws and locking screws of the ring gages are sealed with wax to prevent unauthorized adjustment. Snap gages are also set to a specific size and then the adjustment screws are sealed with wax
The removal of the sharp crest of the thread triangle. It is the front section on a truncated setplug gage.
The back portion of the truncated set plug has a full form profile. The full form thread is sharper & larger than the truncated portion but it still retains a small break so that it is not sharp.
Fixed limit thread gages are popularly known as go and no go thread gages. They are manufactured to predetermine sizes that control minimum and maximum material conditions. The Go thread plug gage inspects the minimum major diameter and the minimum pitch diameter size in a threaded part. The No Go thread plug gage inspects to ensure the threaded hole does not exceed the maximum pitch diameter size in a threaded part. A Go thread ring gage inspects the maximum minor diameter and the maximum pitch diameter size in a threaded part. The No Go thread ring gage checks for the threaded part not to exceed the minimum pitch diameter size on a threaded part.
Gages should be periodically inspected and calibrated to assure accuracy. Go member gages tend to wear quicker with normal use. NOGO gages will wear on the ends that receive the greatest usage. Frequency of inspection and calibration should be dependent on such factors as the amount of usage, part and gage material, tolerance, and quality procedures.
System 21 specifies for interchangeable assembly with reference to functional size only. System 21 specifies that functional size must be measured at the maximum material limit within the length of standard gaging elements. System 21 requires that the NO GO functional diameter must also be verified. This can be accomplished by using a fixed limit gage such as a GO/ NO GO thread plug gage or a variable gage with functional elements such as thread rolls
System 21A specifies for interchangeable assembly with functional size verified at the maximum material limit using standard length gaging elements. This can be performed by using fixed limit gaging such as GO/NOGO thread plug gages or with variable gaging through the use of functional elements. System 21A also requires that the minimum pitch diameter (minimum material limit) be verified by inspecting two thread flank location over the length of the thread. This can be performed with a variable gage or a thread roll snap gage with pitch diameter elements.
System 22 specifies for interchangeable assembly with functional size verified at the maximum material limit using standard length gaging elements. This can be performed by utilizing fixed limit GO/NOGO gaging or variable gaging with functional diameter elements. In addition System 22 requires the verification of the minimum pitch diameter (minimum material limit) over the full length of the thread. This can be performed by using variable gaging such as pitch diameter elements.
System 23 specifies for interchangeable assembly with functional size verified at the maximum material limit using standard length gaging elements. Minimum pitch diameter (minimum material limit) must be verified over the full length of the thread. System 23 includes all the requirements of System 22 as well as the independent verification of lead, flank angle, taper and roundness.
A thread ring gage is an external thread gage employed for the size control of threaded work. American Gage Design - AGD style thread ring gages are adjustable with screws integrated within the gage body. Solid style ring gages are not adjustable and are more popular among international standards. Both styles of gages have their advantages and disadvantages.
A screw thread - hereinafter referred to as a thread, is a ridge of uniform section in the form of a helix on the external or internal surface of a cylinder, or in the form of a conical spiral on the external or internal surface of a cone or frustum of a cone. A thread formed on a cylinder is known as a "straight" or "parallel" thread, to distinguish it from a "taper" thread which is formed on a cone or frustum of a cone.
A male thread is an external thread on the external surface of a cylinder or cone.
A female thread is an internal thread on the internal surface of a hollow cylinder or cone.
Classes of threads are distinguished from each other by the amount of tolerance or tolerance and allowance specified. (Formerly known as "classes of fit" and so designated in Handbook H-28 , government specifications, etc.)
Threaded work parts, bolts, buts, threaded holes and thread gages are usually manufactured in accordance with the thread classes standardized for industry and the Federal Services, Class 1, Class 2 and Class 3, for the American National Series and Class 1A, 1B, 2A, 2B, 3A, and 3B for the Unified Thread Series. The Class chosen by any design engineer for a specific product will depend on its function in service.
Major Diameter on a straight thread is the diameter of the imaginary co-axial cylinder which bounds the crest of an external thread or the root of an internal thread.
The minor diameter is the diameter of an imaginary co-axial cylinder which bounds the root of an external thread or the crest of an internal thread. On a taper thread, the minor diameter, at a given position on the thread axis, is the diameter of the minor diameter cone at that position.
Pitch diameter or simple effective diameter on a straight thread is the diameter of an imaginary co-axial cylinder, the surface of which would pass through the thread profiles at such points as to make the width of the groove equal to one-half of the basic pitch. On a perfect thread this occurs at the point where the widths of the thread and grooves are equal. On a taper thread, the pitch diameter at a given position on the thread axis is the diameter of the pitch diameter cone at that position.
The pitch of a thread is the distance, measured parallel to its axis, between corresponding points on adjacent thread forms in the axial plane and on the same side of the axis.
The lead is the distance a threaded part or gage moves axially, with respect to a fixed mating part, in one complete rotation. On a single-thread screw the lead and pitch are identical; on a double-thread screw the lead is twice the pitch; on a triple-thread screw the lead is three times the pitch, etc.
The included angle of a thread (or angle of thread) is the angle between the flanks of the thread measured in axial plane.
On a straight thread the lead angle is the angle made by the helix of the thread at the pitch line with a plane perpendicular to the axis. On a taper thread, the lead angle at a given axial position is the angle made by the conical spiral of the thread at the pitch line with the plane perpendicular to the axis at that position.
The crest is that surface of the thread which joins the flanks of thread and is farthest from the cylinder or cone from which the thread projects.
The root is that surface of the thread which joins the flanks of adjacent thread forms and is identical with or immediately adjacent to the cylinder or cone from which the thread projects.
The flank (or side) of a thread is either surface connecting the crest with the root, the intersection of which, with an axial plane, is a straight line.
The axis of a thread is the axis of its pitch cylinder or cone.
The depth of thread is the distance between the crest and the base of the thread measured perpendicular to the axis.
The number of threads per inch is the reciprocal of the pitch in inches.
The length of thread engagement of two mating threads is the distance between the extreme points of contact on the pitch diameter cylinders or cones, measured parallel to the axis.
The depth (or height) of thread engagement between two mating threads is the distance, measured perpendicular to the axis, by which their thread forms overlap each other.
A standoff is the axial distance between specified reference points on external and internal taper threaded members or gages, when assembled with a specified torque or under other specified conditions.
An allowance is an intentional difference in the dimension of mating parts. It is the minimum clearance or the maximum interference which is intended between mating parts. It represents the condition of the tightest permissible fit, or the largest male member mated with the smallest female members.
The tolerance on a dimension is the total permissible variation in its size. The tolerance is the difference between the limits of size.
Basic thread size is theoretical or nominal standard size from which all variations are made.
Crest clearance is defined on a screw form as the space between the crest of a thread and the root of its mating thread.
Thread Plug gages are very easy to use. Simply select the correct size thread gage for the corresponding internal threaded product. The go thread plug gage should be screwed into the part with very little force. The engagement should be smooth. The no go thread plug should not enter the part more than 3 turns although in practice it is advisable to limit the amount of turns to 1 1/2 - 2 turns max. The end user should review the applicable thread specification in detail as there are variations to the above practice. Click here for technical document.
Go and no go thread ring gages are very easy to use. Simply select the correct size thread ring gage set for the corresponding externally threaded product. The go thread ring gage should engage the externally threaded part with very little force used. The engagement should be smooth. The no go thread plug should not enter the part more than 3 turns although in practice it is advisable to limit the amount of turns to 1 1/2 - 2 turns max. The end user should review the applicable thread specification in detail as there are variations to the above practice. Click here for technical document.