helical thread inserts
A quick, easy solution that saves you time & money
Materials Available Precision thread helical
inserts meet or exceed
• 18-8 Stainless most applicable specifi-
• (Standard) cations, including:
• Phosphor Bronze MS 122076 series,
124651 series, 21208,
• X 750 Inconel 21209, 33537, Mil-1-
• 316 Stainless 8846 and Mil-F-5577.
Precision Thread Helical Inserts
The Precision insert system was devised for this purpose is the same pitch as the
as a simple method of repairing stripped original thread, but has a larger diam- The Giant in
or damaged threads in any metal or valu- eter. When the insert is installed, the hole the Insert
able parts. Inserts are also used in new is returned to its original size.
products such as die castings or plas- Because the insert provides an en-
tics, where excessive stress on threads larged bearing area, the restored fasten-
could cause damage or failure. ing is stronger than the original. It is also
Precision inserts are helical coils of more durable, since the stainless steel
diamond shaped 18-8 stainless steel thread is generally tougher than the origi-
wire which meets or exceeds AMS-7245 nal material. Precision inserts are corro-
specification. Inserts are sized to provide sion resistant and their 22-microinch or
a precisely controlled interference fit in better surface finish provides a smooth-
an oversized tapped hole. The tap used running, wear-resistant fastening.
Why Precision Thread Helical Inserts?
Precision inserts are used when alter- Replacement of the entire damaged
nate methods of repairing a threaded part could well be impossible as well as
hole are inconvenient, impractical or im- costly and time-consuming.
possible. The Precision system is much While the Precision insert offers an ex-
easier than plugging a damaged hole pedient solution to an immediate prob-
with weld bead, redrilling and tapping. lem, its benefits don’t end there. Almost
It’s usually more practical than using an all threaded fasteners contain minor er-
oversized bolt. rors in pitch of threaded form which tend
to concentrate the load on some threads.
The free coils of the helical thread insert
can flex to accommodate form and pitch
variations, thus distributing the load most Free Running Locking
efficiently over all threads.
Precision inserts are made in all stan- The design is particularly recommended
dard thread sizes and in two basic for applications which require a constant
types…free-running and locking. The locking torque.
Compensation locking type features a crimped turn The Precision system is supplied with
effect corrects which provides an exceptionally strong easy-to-use tooling which facilitates in-
angle and grip on the mating bolt. Locking inserts stallation in almost any location. The
pitch error can be used to eliminate the need for taps, inserts and tools are interchange-
lock washers or other locking devices. able with other helical insert systems.
The first step in creating a new, stronger very strong grip in the hole. Finally, the tool. If necessary, inserts can be re-
thread is cleaning up the original, dam- driving tang is broken off by tapping moved, using one of the extracting tools
aged threads. This is done with a stan- downward with the end of the inserting shown on page eight of this brochure.
dard drill, the size of which is indicated
on the Precision package. The hole is
then tapped with an oversize (STI)* tap
provided in each kit. Kits do not include
drills. Drills are available through your
Precision Helical Thread Insert distribu-
tor. The free diameter of the Precision in-
sert is larger than the new threaded hole,
but it is easily “wound” into place with the
inserting tool provided.
Once in place, the insert tends to spring
back to its original diameter, giving it a Drill Tap Install Tang Removal
2 *Screw Thread Insert
Precision ion NOTE: All kits contain tap, tool, and
inserts. Drills not included.
Thread Repair Sets
Master Range Kit Single Repair Kit
Mini Order Mini Order
Kits No. Kits No.
UNC 6-32 8-32 10-24 87902 M4x.7 M5x.8 M6x1 87905
UNF 6-40 8-36 10-32 87903 M6x1 M8x1 M10x1 87906
UNC /4-20 5/16-18 3/8-16 87900 M8x1.25 M10x1.5 M12x1.75 87907
1 5 3
UNF /4-28 /16-24 /8-24 87901
Master Order Master Order
Kits No. Kits No.
UNC /4-20 /16-18 COARSE M5x.8 M6x1
3 7 1
/8-16 /16-14 /2-13 87910 M8x.1.25 M10x1.5 M12x1.75 87915
UNF /4-28 /16-24 FINE M8x1 M10x1
3 7 1
/8-24 /16-20 /2-20 87911 M10x.1.25 M11x1 M12x1.5 87916
Big Boy Order Big Boy Order
Kits No. Kits No.
UNC /8-11 /4-10 7/8-9 87912 M14x2 M16x2 M18x2.5 87917
UNF /8-18 3/4-16 7/8-14 87913 M14x1.5 M16x1.5 M18x1.5 87918 Total Kit - Combination
Total Kit Order Total Kit Order Total Kit Order
American No. Metric No. Combination No.
WITHOUT LOCK 87923 WITHOUT LOCK 87927 WITHOUT LOCK 87920
WITH LOCK 87925 WITH LOCK 87929 WITH LOCK 87924
Contains: Contains: Contains:
1 - 87910 Master Kit 1 - 87915 Master Kit 1 - 87910 Master Kit
1 - 87911 Master Kit 1 - 87916 Master Kit 1 - 87911 Master Kit
1 - 87912 Big Boy Kit 1 - 87917 Big Boy Kit 1 - 87915 Master Kit
1 - 87913 Big Boy Kit 1 - 87918 Big Boy Kit 1 - 87916 Master Kit 3
Strip Feed Inserts
(When assembly line installation of inserts is required)
INSERT INFO REQUIRED
1. Insert size
2. Insert length
3. Free running or locking
4. Coatings or platings if any
TOOLING INFO REQUIRED
1. Electric tool
2. Air driven
3. Pedestal to hold tool and reel
Air Driven Electrically Driven
Call For Pricing
Precision Thread Tooling
COMBINATION HAND TOOLS
Simple, easy to use. Also has a SECOND function
as the tang break-off tool.
Recommended for semi and production applications.
Speeds installation and saves time.
The simple and time-saving method for removing the insert.
Four sizes cover all thread sizes.
High speed steel taps available in straight flute,
spiral point, spiral flute, in plug and bottoming style.
Complete go and no go thread gages with handle.
(Note - Thread should be checked for size before the insert is installed.)
8 Call For Pricing 10/04