Nut, Plain, Hexagon, Machine Screw, UNC-2B, from MS35649 Rev. H. Every row below is transcribed from the standard and has its own link.
MS35649 at a glance
MS35649Engineering drawing · dimensions in inches
Current standard: NASM35649. MS35649 is now controlled by NASM35649 (MS35649H Notice 2 (8 Aug 2002)). The part numbers do not change: MS35649-222 is still the number on drawings, IPCs and bags, and it is the same part. Order it by that number; the current document is NASM35649.
Specification
Item
Value
Current standard
NASM35649 (part numbers unchanged)
Type
Plain hex nut
Material
Carbon steel per the procurement specification. CRES: series 302 thru 305 (UNS S30200 thru S30500), 316 (UNS S31600), 317 (UNS S31700) and 347 (UNS S34700). Brass: alloy 462 (UNS C46200) or 464 (UNS C46400) per QQ-B-637, or alloy 360 (UNS C36000) per QQ-B-626. Copper silicon alloy 651 (UNS C65100) per QQ-C-591. CRES nuts: magnetic permeability 2.00 max (air = 1.00) at H = 200 oersteds, tested with an indicator per MIL-I-17214.
Locking
None (plain nut)
Item
Value
Finish
Carbon steel: cadmium plate or phosphate coating per the procurement specification. CRES: cleaned, descaled (ASTM A380) and passivated (QQ-P-35); black oxide per MIL-C-13924, Class 4. Brass: black oxide per the procurement specification; tin plated per ASTM B545, .0001 in. thick; silver plated per QQ-S-365, .0001 in. thick; nickel plated per the procurement specification.
Procurement
FF-N-836
Status
Cancelled. Rev. H (12 Feb 1988) was made inactive for new design by Notice 1 (3 Feb 2000; replacement use only) and cancelled by Notice 2 (8 Aug 2002), superseded by NASM35649 with identical part numbers.
Dimensions by size
Dimension, in
.0860-56 UNC-2B
.1120-40 UNC-2B
.1380-32 UNC-2B
.1640-32 UNC-2B
.1900-24 UNC-2B
.2500-20 UNC-2B
.3125-18 UNC-2B
.3750-16 UNC-2B
F — Width across flats
.187 – .180
.250 – .241
.312 – .302
.344 – .332
.375 – .362
.437 – .423
.562 – .545
.625 – .607
G — Width across corners
.217 – .205
.289 – .275
.361 – .344
.397 – .378
.433 – .413
.505 – .482
.650 – .621
.722 – .692
H — Thickness
.066 – .057
.098 – .087
.114 – .102
.130 – .117
.130 – .117
.193 – .178
.225 – .208
.257 – .239
Maximum – minimum as tabulated in MS35649 Rev. H; letters as on the standard's drawing.
Every part number of MS35649 Rev. H, each with its own link. Codes (material, finish) build the full number in the box below.
Part number
What each code means
Part
Meaning
Format
MS35649-<dash>{finish}
(none)
Finish: No finish letter: carbon steel, cadmium plated or phosphate coated (no suffix is permitted with these coatings); the dash number already fixes the material
B
Finish: Black oxide coated (the standard brass nut; also available on CRES, MIL-C-13924 Class 4)
N
Finish: Nickel plated
S
Finish: Silver plated (.0001 in. thick)
T
Finish: Tin plated (.0001 in. thick)
cad
Material: Carbon steel, cadmium plated (dash number in the CAD column)
MS35649-225B — .0860-56 UNC-2B machine-screw nut, plain hexagon, brass, black oxide coated. Since Rev. F brass nuts carry the letter B for black oxide; before Rev. F the B was not used, but in either case brass nuts have black oxide.
Notes from the standard
Dimensions in inches. Nuts are Type II, Style 13 per the procurement specification; free of loose or hanging burrs and slivers.
Dash numbers depend on material: the CAD column dash is shown as the basic part number; the other material dashes are in the extra columns. The 1/4 and 5/16 and 3/8 sizes have no phosphate-coated version.
Threads per FED-STD-H28/2; acceptability of screw threads per FED-STD-H28/20, System 21.
Cancelled dash numbers of the original issue (cancelled after 8 Sep 1966) are replaced by the numbers shown in cancelled_dashes; the sheet also lists AN340, AN341, MS16210 and MS20341 dash numbers cancelled after 17 Apr 1968 and superseded by MS35649 (not transcribed).
In the event of conflict between the text of this standard and the references cited, the text of this standard takes precedence.
MS35649 Rev. H, 12 Feb 1988 — Nut, Plain, Hexagon, Machine Screw, UNC-2B — dimensions, part numbers and notes. Public domain, distribution unlimited. Notices: Notice 1 (3 Feb 2000): MS35649H inactive for new design and no longer used except for replacement purposes.; Notice 2 (8 Aug 2002): MS35649H cancelled and superseded by NASM35649; the part identification number of MS35649H and the part number of NASM35649 are identical, part numbers unchanged (example MS35649-225B).
Educational reference only. not approved data. Always consult the applicable SRM, AMM, or AC 43.13-1B and your certifying authority.
