? Screw head diameter?

[Michael Horowitz]

MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
application the diameter of the screwhead is important.

I went to HD and bought a 6-32 machine screw to see what length I
needed (the original having rusted beyond recognition). I compared the
HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
so I'm wondering if I order the MS screw if the head will be large
enough.

The difference I'm seeing is caused by the 100^ angle on the MS screw,
but I don't know if the final diameter will match the original.

Would anyone with experience with the MS24593 screw please weigh in? -
Mike

[Morgans[_2_]]

"Michael Horowitz" > wrote in message
...
> MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
> application the diameter of the screwhead is important.
>
> I went to HD and bought a 6-32 machine screw to see what length I
> needed (the original having rusted beyond recognition). I compared the
> HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
> so I'm wondering if I order the MS screw if the head will be large
> enough.
>
> The difference I'm seeing is caused by the 100^ angle on the MS screw,
> but I don't know if the final diameter will match the original.
>
> Would anyone with experience with the MS24593 screw please weigh in? -

I would be very curious as to what the application is for this screw.

If it is going to be any more important than holding a radio in the panel,
then you need to be thinking about the quality and strength of the screw.

HD screws have no strength guarantee, compared to a MS screw. They may have
only 10% of the strength of a MS screw. If that is the case, the head size
is the least of your worries.

I hope you are not using hardware store screws in your homebuilt for any
important functions. You are gambling your life. You could be a _big_
looser.
--
Jim in NC

[Michael Horowitz]

On Mon, 1 Jan 2007 09:47:48 -0500, "Morgans"
> wrote:


>
>I hope you are not using hardware store screws in your homebuilt for any
>important functions. You are gambling your life. You could be a _big_
>looser.


No, no, no, no

We do not use hardware from Home Depot Aerospace for anything except
non-structural things like holding the floorboards in place.

I mentioned HD and the cml screw because I thought the cml screw would
have the same profile as the MS screw and I could use it as a model of
what to purchase. What I didn't realize is that the underside angle of
the head (countersink) for the MS screw was different from the cml
screw, so that was a good idea gone bad.

Still don't know if a #6 MS24694 is going to give me a 3/8" dia head.

[Rich S.[_1_]]

"Morgans" > wrote in message
...
>
> I hope you are not using hardware store screws in your homebuilt for any
> important functions. You are gambling your life. You could be a _big_
> looser.

Doggone it, Morgan! Only six hours and forty-seven minutes into the new year
and you've already done it!

We've told you before, it's LOSER. Looser pertains to the state of your
bowels. :}

Rich S.

[John Kunkel]

"Michael Horowitz" > wrote in message
...
> MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
> application the diameter of the screwhead is important.
>
> I went to HD and bought a 6-32 machine screw to see what length I
> needed (the original having rusted beyond recognition). I compared the
> HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
> so I'm wondering if I order the MS screw if the head will be large
> enough.

A 6-32 countersunk screw with a 3/8" diameter head? Even a 10-32 screw with
a 100° countersink will barely be 3/8".

If you meant 3/16", then the difference in the head diameter is due to the
87° or 90° countersink on the hardware store screw.

[Michael Horowitz]

On Mon, 1 Jan 2007 09:59:15 -0800, "John Kunkel" >
wrote:

>
>"Michael Horowitz" > wrote in message
...
>> MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
>> application the diameter of the screwhead is important.
>>
>> I went to HD and bought a 6-32 machine screw to see what length I
>> needed (the original having rusted beyond recognition). I compared the
>> HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
>> so I'm wondering if I order the MS screw if the head will be large
>> enough.
>
>A 6-32 countersunk screw with a 3/8" diameter head? Even a 10-32 screw with
>a 100° countersink will barely be 3/8".
>
>If you meant 3/16", then the difference in the head diameter is due to the
>87° or 90° countersink on the hardware store screw.

I do believe you are correct; and I think I solved my problem.
Blueprint shows a simple 6-32 machine screw used vice the flat head;
I'll take that approach using an AN526 and countersink that - Mike

>

[Morgans[_2_]]

"Rich S." > wrote in message
. ..
> "Morgans" > wrote in message
> ...
>>
>> I hope you are not using hardware store screws in your homebuilt for any
>> important functions. You are gambling your life. You could be a _big_
>> looser.
>
> Doggone it, Morgan! Only six hours and forty-seven minutes into the new
> year and you've already done it!
>
> We've told you before, it's LOSER. Looser pertains to the state of your
> bowels. :}

CRAP ! ! ! <g>

The thing of it is, is that I nowe beter then that! ;-)
--
Jim in NC

[flybynightkarmarepair]

Michael Horowitz wrote:
> MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
> application the diameter of the screwhead is important.
>
> I went to HD and bought a 6-32 machine screw to see what length I
> needed (the original having rusted beyond recognition). I compared the
> HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
> so I'm wondering if I order the MS screw if the head will be large
> enough.
>
> The difference I'm seeing is caused by the 100^ angle on the MS screw,
> but I don't know if the final diameter will match the original.
>
> Would anyone with experience with the MS24593 screw please weigh in? -
> Mike

http://assist.daps.dla.mil/quicksearch/basic_profile.cfm?ident_number=40617

Rev C has the complete dimensional specs.

[Rich S.[_1_]]

"Morgans" > wrote in message
...
>
> CRAP ! ! ! <g>
>
> The thing of it is, is that I nowe beter then that! ;-)

That's ok. Hppy New yere anway. I fogot the rule that any post correcting
speling has to contain at least too errors.

Ricih S.

[Morgans[_2_]]

"Rich S." > wrote in message
. ..
> "Morgans" > wrote in message
> ...
>>
>> CRAP ! ! ! <g>
>>
>> The thing of it is, is that I nowe beter then that! ;-)
>
> That's ok. Hppy New yere anway. I fogot the rule that any post correcting
> speling has to contain at least too errors.
>
> Ricih S.

Foregiveden.

Happy New Year to you, too, and may the number of takeoffs you log equal the
number of landings you log.
--
Jim in NC

[jls]

Morgans wrote:
> "Michael Horowitz" > wrote in message
> ...
> > MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
> > application the diameter of the screwhead is important.
> >
> > I went to HD and bought a 6-32 machine screw to see what length I
> > needed (the original having rusted beyond recognition). I compared the
> > HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
> > so I'm wondering if I order the MS screw if the head will be large
> > enough.
> >
> > The difference I'm seeing is caused by the 100^ angle on the MS screw,
> > but I don't know if the final diameter will match the original.
> >
> > Would anyone with experience with the MS24593 screw please weigh in? -
>
> I would be very curious as to what the application is for this screw.
>
> If it is going to be any more important than holding a radio in the panel,
> then you need to be thinking about the quality and strength of the screw.
>
> HD screws have no strength guarantee, compared to a MS screw. They may have
> only 10% of the strength of a MS screw. If that is the case, the head size
> is the least of your worries.
>
> I hope you are not using hardware store screws in your homebuilt for any
> important functions. You are gambling your life. You could be a _big_
> looser.
> --
> Jim in NC

A big looser? What is he going to loose? A goose?

Anyway, what he's doing is restoration and the screws he's using
probably hold on a leading edge of aluminum sheet or attach ribs to a
spar. That's why they rust beyong recognition. If they were on a
Taylorcraft wing or aileron, for instance, they were off-the-shelf
screws. So using them would in all likelihood not make him any
"looser."

Anyway I doubt if the PK screws used in such a case are (or were) the
same Air Force-Navy quality you find in an AN bolt or nut.

I have removed some of those screws from an old certified airframe and
the heads break all to hell.

I know an A&P who bought all his screws for the rib-to-spar fasteners
and LE on a J-3 at the local hardware store. Does that mean he's loose
as a goose? Or looser?

[Morgans[_2_]]

"jls" > wrote

> I know an A&P who bought all his screws for the rib-to-spar fasteners
> and LE on a J-3 at the local hardware store. Does that mean he's loose
> as a goose? Or looser?

I would have to believe that they do not meet specifications for repairing a
certified aircraft.

I might trust them for holding skin down, but not much more than that. No,
I take that back. I don't trust them that far.

Have you seen the quality of the hardware nuts and bolts and screws, lately?
Chinese steel is of such low quality, I would be surprised if it was 25% the
strength of a part to MilSpec part comparison.

No, I would not bet my life on the saving of a few bucks by using unknown
hardware screws. If I'm that short of cash, I will go fly model airplanes,
or something.
--
Jim in NC

[jls]

Morgans wrote:
> "jls" > wrote
>
> > I know an A&P who bought all his screws for the rib-to-spar fasteners
> > and LE on a J-3 at the local hardware store. Does that mean he's loose
> > as a goose? Or looser?
>
> I would have to believe that they do not meet specifications for repairing a
> certified aircraft.
>
> I might trust them for holding skin down, but not much more than that. No,
> I take that back. I don't trust them that far.
>
> Have you seen the quality of the hardware nuts and bolts and screws, lately?
> Chinese steel is of such low quality, I would be surprised if it was 25% the
> strength of a part to MilSpec part comparison.
>
> No, I would not bet my life on the saving of a few bucks by using unknown
> hardware screws. If I'm that short of cash, I will go fly model airplanes,
> or something.
> --
> Jim in NC

You've got a point. I buy all my PK-type screws from ACS but even then
I get some I don't like. The CRS screws I have quit using because they
tend to break.

[Cy Galley]

Looks like about 5/16 for #6


"flybynightkarmarepair" > wrote in message
oups.com...
>
> Michael Horowitz wrote:
>> MS24593 is a flat head machine screw with a 6-32 shank/thread. In this
>> application the diameter of the screwhead is important.
>>
>> I went to HD and bought a 6-32 machine screw to see what length I
>> needed (the original having rusted beyond recognition). I compared the
>> HD screw with the MS and noticed it was 1/4" dia. as compared to 3/8",
>> so I'm wondering if I order the MS screw if the head will be large
>> enough.
>>
>> The difference I'm seeing is caused by the 100^ angle on the MS screw,
>> but I don't know if the final diameter will match the original.
>>
>> Would anyone with experience with the MS24593 screw please weigh in? -
>> Mike
>
> http://assist.daps.dla.mil/quicksearch/basic_profile.cfm?ident_number=40617
>
> Rev C has the complete dimensional specs.
>

[GeorgeB]

On Mon, 01 Jan 2007 11:06:27 -0500, Michael Horowitz
> wrote:

>On Mon, 1 Jan 2007 09:47:48 -0500, "Morgans"
> wrote:
>
>I mentioned HD and the cml screw because I thought the cml screw would
>have the same profile as the MS screw and I could use it as a model of
>what to purchase. What I didn't realize is that the underside angle of
>the head (countersink) for the MS screw was different from the cml
>screw, so that was a good idea gone bad.
>
>Still don't know if a #6 MS24694 is going to give me a 3/8" dia head.

Head diameter, 0.3765 to 0.3813. Google is your friend,
http://www.hi-shear.com/standards/hst13.pdf

There are several head angles common, 82, 90, 100, and 118 which I've
used in various applications for various reasons.