Home Determining Your Lathe Spindle Thread to find the correct NOVA insert adapter

Determining Your Lathe Spindle Thread to find the correct NOVA insert adapter

Determining Your Lathe Spindle Thread to find the correct NOVA insert adapter

1. Refer to the insert/adaptor chart (below) to see if your lathe is listed.
If listed make a note of the SKU:______ (example IDNS, IENS, etc)

2. If not listed, look in your manual or sales literature to find the thread size.

Make a note of these:
Machine make:
Machine model thread size (if known):
Inboard thread (LH – left hand or RH right hand or both:
(Look at our insert/adaptor chart below to find your size)

3. If you don’t have a manual, contact your supplier to get a copy of your manual and find out your spindle size. If they don’t have the info you can call your manufacturer. (Then look at our insert/adaptor chart below to find your size).

4. If you have reliable information for your spindle thread size but there is no match on the chart, you may have
an unusual lathe that NOVA doesn’t have an adaptor for. You will need to purchase a blank chuck or a blank insert/adaptor and get it threaded to your requirements.

5. If you can’t find the information on your spindle thread size you will need to take some measurements on your lathe spindle. You only need to do these measurements if you can’t find the info anywhere else.

1. Outside diameter of thread:
2. Pitch of thread:
3. Length of thread:
4. Register diameter:
5. Register length:

Ensure that the thread on the adapter and lathe spindle has the exact same pitch and standard. Even if the thread size is the same there are different standards of threads, e.g. UNC/UNF and BSW. If mismatching standard threads are used it may cause damage to both lathe and chuck therefore you will have to know the thread of the spindle accurately.
A reference to quickly distinguish between Unified (UNC or UNF) and British (BSF or BSW) standards:

FLAT TOP = 60° angle (UNC, UNF, Metric threads)                           ROUND TOP = 55° angle: Whitworth, BSW, BSF 


BSF: British Standard Fine
BSW: British Standard Whitworth
RH: Right hand
LH: Left hand
TPI: Threads per inch
UN: Unified National Standard
UNC: Unified Coarse Standard
UNF: Unified Fine Standard
UNS: Unified Special

These thread sizes listed are the size which the adaptor converts to (e.g. The thread size listed in the table should match the thread size on your lathe spindle.)

Chuck Inserts from NOVA

SKU Thread
Pitch Thread
Standard Compatible
Set Screw
I2NS M20 2  Tyme Cub
I3NS M20 1.5  Electra Beckum,
Multico Sumaro
I6NS 3/4″ Plain Bore  M6
I7NS 1 1/8″ 8TPI UN(NOT UNC)
I8NS 7/8″ 12TPI LH NS
I9NS 3/4″ 16TPI RH (with 6mm register)
IANS 3/4″ 4TPI RH BSP  TL1000 (pre 1986)
IBNS 3/4″ 4TPI LH BSP  TL1000 (pre 1986)
ICNS 1″ 10TPI RH BSF  TL1000, Woodfast/Durden
IDNS 1″ 8TPI RH UNC  Delta, Rockwell, Golding,
General, NOVA Comet (North America)
and Mercury lathes
IENS 1″ 12TPI RH UNF  Myford ML8
IHNS 3/4″ 10TPI RH BSW  Rockwell
IINS M24 3 RH  B-Line
Arundel K600/K450
IJNS 1 1/8″ 12TPI RH  BSW  Myford Mystro
Masterlathe (New Zealand)
IKNS M18 2.5 RH  Elu DB 180
ILNS 1 1/4″ 8TPI RH  NOVA Galaxi, NOVA Saturn, NOVA DVR 3000, NOVA XP, NOVA 1624 and 1624 II (North America),
Laguna Revo
IMNS 1″ 10TPI LH BSF  TL1000
INNS Blank (Can be threaded up to 28mm)
IONS 1 1/8″ 7TPI RH BSW Morton
IQNS M30 3.5 RH NOVA TL1500/3000/Comet
(European & Southern Hemisphere)
IRNS 1″ 8TPI RH Jet 1221 Lathe
ISNS 5/8″ Plain Bore Designed Specifically for
Shopsmith Pro V and
Power Pro Machines
ITNS 1″ 8TPI Dual Threaded LH and RH NOVA Mercury Mini Lathe
IUNS 1 1/8″ 12TPI RH UNF Taiwanese lathes
IYNS 1 1/4″ 8TPI RH For lathes don’t
have reverse turning ability
IWNS M25 2 RH  Tyme Avon (’83 on) and Classic Tanner SD165, Selbix Springwood, Sorby, Cotech
IXNS 1″ 8TPI RH Designed specifically for the
NOVA Comet II Midi Lathe,
features lock for the reverse function.