MS20074-05-24 bolts

Well there is a little more to it. I'm assisting other builders and the
bolt count goes up @ 4/ ship and it adds up quickly. I'm sure that there is
a source somewhere at more like $10/bolt I bought "Supertanium" bolts for
less than $20 each and these are a high strength Titatanium alloy in the
200ksi region.
The MS are of the grade 5 variety, coarse thread and the only thing special
is the drilled head. $20 each is excessive.
Stu
"Gig601XLBuilder" wrote in message
...
In that case I doubt I'd bitch about the $80 cost for 4 bolts.


Stuart & Kathryn Fields wrote:
Well, I use 4 of these bolts in the "Jesus" bolt position whose job is
to keep my my entire rotor blade system from departing like a kids toy.
Yes, I want to be 500' in the air not even wondering if I got the bolts
that I thought I did.

Stu
"Maxwell" wrote in message
...
"cavelamb himself" wrote in message
...
wrote:
On Jan 3, 2:45 pm, "Stuart & Kathryn Fields" wrote:

Recent quote for 16 of these bolts was about $20.00 each!! Anyone
out there
with a less expensive source?

Since I presume you're dealing with an experimental aircraft, and a
MS20074 bolt is a coarse thread (the only coarse thread aircraft
structural bolt I know of), 125 ksi, drilled head hex bolt, why not
just use a grade 5 or grade 8 auto bolt? They are quite good quality
if you buy from the right source. Try some of the race car suppliers
maybe.

Regards,
Bud

It might be quite good quality - or it might be junk.

How are you going to know???
If you go with a quailty manufacturer that will certify the grade,
specify rolled threads, and have them individually magnafluxed, you
should be good to go.

On Jan 4, 10:05*am, "Stuart & Kathryn Fields" wrote:
The MS are of the grade 5 variety, coarse thread and the only thing special
is the drilled head. *$20 each is excessive.

How about you buy a full box of Grade 8 bolts, test half or quarter of
them to destruction in shear and tension, and then reject the box if
any fail below expected values. If they pass, test the rest to the
implementation design limits and then drill the heads on your drill
press using a carbide bit. That might work.

Bob K.

arp-bolts had stronger bolts but no drilled heads.
Thanks
Stu
"Skrud" wrote in message
...
These guys might be able to help. It'd certainly be worth a phone call to
see what they can do.

Not sure I'd tell them what they're for though...

The spec's ma'am, just the spec's.

http://www.arp-bolts.com/

"Bob Kuykendall" wrote in message
...

How about you buy a full box of Grade 8 bolts, test half or quarter of
them to destruction in shear and tension, and then reject the box if
any fail below expected values. If they pass, test the rest to the
implementation design limits and then drill the heads on your drill
press using a carbide bit. That might work.

+++++++++++++++++++++++++++++++++++

I did that with my prop bolts. Better buy twice as many plus a dozen extra
carbide bits. Anybody wanna buy about six grade 8 prop bolts with busted
carbide bits imbedded in the hex heads?

Rich S.

Rich S. wrote:
"Bob Kuykendall" wrote in message
...

How about you buy a full box of Grade 8 bolts, test half or quarter of
them to destruction in shear and tension, and then reject the box if
any fail below expected values. If they pass, test the rest to the
implementation design limits and then drill the heads on your drill
press using a carbide bit. That might work.

+++++++++++++++++++++++++++++++++++

I did that with my prop bolts. Better buy twice as many plus a dozen extra
carbide bits. Anybody wanna buy about six grade 8 prop bolts with busted
carbide bits imbedded in the hex heads?

Rich S.



I have to report the same levels of sucess!

Those tiny little bits break when they start to come out the bottom side.

BTW, Why Grade 8?
Seems like those might be a but - brittle?


Richard

cavelamb himself wrote:


I have to report the same levels of sucess!

Those tiny little bits break when they start to come out the bottom side.

BTW, Why Grade 8?
Seems like those might be a but - brittle?


Richard

Because a grade 8 bolt on a bad day still beats a grade 5 for strength
on its best day. Someone showed the numbers on that issue either here or
one of the list-servers I subscribe to.

Dave

Dave S wrote:
cavelamb himself wrote:


I have to report the same levels of sucess!

Those tiny little bits break when they start to come out the bottom side.

BTW, Why Grade 8?
Seems like those might be a but - brittle?


Richard


Because a grade 8 bolt on a bad day still beats a grade 5 for strength
on its best day. Someone showed the numbers on that issue either here or
one of the list-servers I subscribe to.

Dave


I don't recall it here.
How about share if you can find it.


IIRC, AN bolts are grade 5 types to allow them to bend before braking.

"cavelamb himself" wrote in message
...
Dave S wrote:
cavelamb himself wrote:


I have to report the same levels of sucess!

Those tiny little bits break when they start to come out the bottom
side.

BTW, Why Grade 8?
Seems like those might be a but - brittle?


Richard


Because a grade 8 bolt on a bad day still beats a grade 5 for strength on
its best day. Someone showed the numbers on that issue either here or one
of the list-servers I subscribe to.

Dave


I don't recall it here.
How about share if you can find it.


IIRC, AN bolts are grade 5 types to allow them to bend before braking.

What Dave said, plus a couple more reasons . . .

The size I needed was only available in Grade 8. IIRC, they are 3/8" NC,
about 8" long.

Prop bolts are typically NAS - not AN.

I keep a close eye on them, checking them at every oil change. I have a wood
prop, so that's a good idea no matter what grade of bolts are used. They've
400 hours on them now and have never loosened nor shown signs of wear or
slippage. Someday I'm going to take a picture of the bolt circle with the
safety wire properly installed so's I don't have to spend 20 minutes
figuring out which *&^% way the wire goes in and which way to twist it.

Rich S.

cavelamb himself wrote:


I don't recall it here.
How about share if you can find it.


IIRC, AN bolts are grade 5 types to allow them to bend before braking.

I will look.. but the gist of it is.. a grade 5 will still fail
completely before the grade 8 starts to get strained... brittle versus
bending is besides the point in that regard.

Dave S wrote:
cavelamb himself wrote:


I don't recall it here.
How about share if you can find it.


IIRC, AN bolts are grade 5 types to allow them to bend before braking.

I will look.. but the gist of it is.. a grade 5 will still fail
completely before the grade 8 starts to get strained... brittle versus
bending is besides the point in that regard.

Here is a link to a grade chart I found in the FlyRotary listserv
messages. The original message I recall is not under the heading of
bolts or grades.. i've got years of messages to look through if I was to
find it.

Dave