Machine Screw Dimensions 1

[dd4eng]

I'm trying to find dimensions for machine screws defined within ANSI B18.6.3. Mainly Phillips drive (cross recessed) are the ones I'm interested in. I have Machinery’s
Handbook 26 but it has dimensions for slotted machine screws.

If anyone has any reference material showing the dimensions of phillips head machine screws (82 and 100 degree flat head, pan head) it would be of help.

thanks.

 

[Heckler]

What about the Machinerys Handbook? They list dimensions of standard mechanical hardware.

Heckler
Sr. Mechanical Engineer
SWx 2007 SP 3.0 & Pro/E 2001
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(In reference to David Beckham) "He can't kick with his left foot, he can't tackle, he can't head the ball and he doesn't score many goals. Apart from that, he's all right." -- George Best

 

[dd4eng]

Yes for SLOTTED machine screws. I need dimensions for cross recessed machine screws.

 

[Heckler]

Try downloading MIL-STD-1251A - Screws & Bolts.

Here is some information:

Torq-set Recess

NAS1151-1158, 2903-2910
NAS1580, 1581, 1972-1980, 1992-2000

Heckler
Sr. Mechanical Engineer
SWx 2007 SP 3.0 & Pro/E 2001
XP Pro SP2.0 P4 3.6 GHz, 1GB RAM
NVIDIA Quadro FX 1400
o
_`\(,_
(_)/ (_)

(In reference to David Beckham) "He can't kick with his left foot, he can't tackle, he can't head the ball and he doesn't score many goals. Apart from that, he's all right." -- George Best

 

[drawoh]

dd4eng,

The dimensions for phillips flat head machine screws are the same as for slotted. Try the following website...

http://www.barnhillbolt.com/

These guys keep good drawings online. They even have good drawings of metric pan head (cheese head?) screws.

JHG

 

[KENAT]

I have some links on my PC at work, do a few well thought out google searches and you should find it. From memory the slotted & Phillips are the same envelope per Heckler, but looking at drawoh’s link it appears heights are different.

http://www.barnhillbolt.com/specs/ScrewPanHeadMachine.htm

When you come to the North American version of metric pan heads V the rest of the worlds version you have problems too.

 

[dd4eng]

Thanks guys. I wasn't sure if slotted and phillips have the same dimensions.

that Barnhill bolt site is quite good. thanks JHG for the tip.

 

[Philrock]

Head diameters are the same. Head heights are NOT the same. Phillips have taller heads.

 

[unclesyd]

Checkout this site. The standard is ASME 18.6.3.
You will have to look to get fasteners made to this standard as most are now imported. It has been my experience that there is considerable difference in head height and slot depth on imported fasteners in the US.

http://www.smithfast.com/trussrndfill.html#round

 

[fcsuper]

I would recommend getting spec drawings from the manufacture or distributor. This doesn't solve the issue, but it helps clarify it. In fact, it's not uncommon to see tolerances at huge ranges spec'd for stated dimensions when it comes to the heads themselves (though lengths tend to be much tighter). Manufacturers are not bound to the standards nearly as much as we'd like to think. At my company, we've had issues with major changes occuring on screws between lots.

If the matter is critical, it may be necessary to work directly with the manufacture to produce what you expect. If the matter isn't critical, then perhpas its not someting worth worrying about.

Matt
CAD Engineer/ECN Analyst
Silicon Valley, CA
sw.fcsuper.com
Co-moderator of Solidworks Yahoo! Group