do metric threads come in three classes of clearance fit?

[Ozix]

I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But it
also looks like the female thread in the lock is undersize. WTF?

[Daryl]

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But it
also looks like the female thread in the lock is undersize. WTF?

There is more to a thread than just its diameter, pitch or threads per
mm also vary, its just a matter of finding the correct screw/bolt.

[Xeno]

Post by Daryl

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But
it also looks like the female thread in the lock is undersize. WTF?

There is more to a thread than just its diameter, pitch or threads per
mm also vary, its just a matter of finding the correct screw/bolt.

It's a matter of *knowing* what screw to find or, more importantly,
order. That means you need to correctly identify what you have.

https://boltdepot.com/Fastener-Information/Identifying-Fasteners

Ozix should look at the screws he has remaining and identify it in
accordance with the information in the link above.

[Xeno]

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting

Sounds like the thread pitch is wrong. Have you got one of these handy?

https://generaltools.com.au/product/moore-wright-iso-metric-screw-pitch-gauge/

Post by Ozix
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But it
also looks like the female thread in the lock is undersize. WTF?

[Mighty Mouse]

Post by Xeno

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5
screws in junk box will only go two and a half turns then bind. Putting

Sounds like the thread pitch is wrong. Have you got one of these handy?
https://generaltools.com.au/product/moore-wright-iso-metric-screw-pitch-gauge/

that reminds me on feeler gauges we used for setting points gaps. they
came like that

Post by Xeno

Post by Ozix
calliper on the rolladoor screw, it is 0.1 mm smaller than the
others. So it looks like they used the "easy to assemble" class of
screw. But it also looks like the female thread in the lock is
undersize. WTF?

[Xeno]

Post by Mighty Mouse

Post by Xeno

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5
screws in junk box will only go two and a half turns then bind. Putting

Sounds like the thread pitch is wrong. Have you got one of these handy?
https://generaltools.com.au/product/moore-wright-iso-metric-screw-pitch-gauge/

that reminds me on feeler gauges we used for setting points gaps. they
came like that

Yup, hand, convenient and protected, all in the one package - as long as
you kept them oiled up.

Post by Mighty Mouse

Post by Xeno

Post by Ozix
calliper on the rolladoor screw, it is 0.1 mm smaller than the
others. So it looks like they used the "easy to assemble" class of
screw. But it also looks like the female thread in the lock is
undersize. WTF?

[Noddy]

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But it
also looks like the female thread in the lock is undersize. WTF?

The "WTF" part here is that you don't understand what you're looking at.

There is no such thing as "classes of clearance" for fasteners. What
there is is diameter and pitch and that applies equally to both metric
and imperial fasteners. Don't automatically assume that the thread
you're looking at is metric, as many people still cut imperial threads
in parts using thread cutting equipment that is decades old.

Screwing the wrong bolt into the hole will fuck it completely, so for
your sake I would take the remaining original screw to a bolt
specialist, hardware store or anyone else who can help you out to get a
replacement.

[Xeno]

Post by Noddy

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But
it also looks like the female thread in the lock is undersize. WTF?

The "WTF" part here is that you don't understand what you're looking at.
There is no such thing as "classes of clearance" for fasteners. What
there is is diameter and pitch and that applies equally to both metric
and imperial fasteners. Don't automatically assume that the thread
you're looking at is metric, as many people still cut imperial threads
in parts using thread cutting equipment that is decades old.
Screwing the wrong bolt into the hole will fuck it completely, so for

No doubt Darren speaking from experience in doing just that!

Post by Noddy
your sake I would take the remaining original screw to a bolt
specialist, hardware store or anyone else who can help you out to get a
replacement.

[Xeno]

Post by Noddy

Post by Ozix
I removed the lock from a rolladoor to paint it, and lost on of the
screws. The other fits an M5 screw guage, but is sloppy. The M5 screws
in junk box will only go two and a half turns then bind. Putting
calliper on the rolladoor screw, it is 0.1 mm smaller than the others.
So it looks like they used the "easy to assemble" class of screw. But
it also looks like the female thread in the lock is undersize. WTF?

The "WTF" part here is that you don't understand what you're looking at.
There is no such thing as "classes of clearance" for fasteners. What

Again, you talk out of your arse.

https://amesweb.info/Screws/Metric-Clearance-Hole-Chart.aspx#google_vignette

https://engineersbible.com/clearance-hole-metric/

https://fractory.com/metric-bolt-clearance-hole-size-chart/

https://fractory.com/imperial-bolt-clearance-hole-size-chart/

Classes of clearance for *fasteners* Darren. You were saying??

Post by Noddy
there is is diameter and pitch and that applies equally to both metric
and imperial fasteners. Don't automatically assume that the thread
you're looking at is metric, as many people still cut imperial threads
in parts using thread cutting equipment that is decades old.

I mentioned in a previous post that a thread gauge will be his best
friend here. Any bolt of the correct size but which only threads in
freely for two or three turns, then binds up, is facing an incorrect
pitch issue. That's why the smart (and properly trained) people never
force such things because then you'll end up with either a screwed up
thread or a broken off bolt

Anyway, most stuff in *Australia* has been metric for *decades* and
testing for (and assuming) metric sizes first makes a whole lot of
sense. Since your *experience* is on old ancient shit, I'm not at all
surprised you still live in the Imperial era, eh Mr All Imperial Jeep??

Post by Noddy
Screwing the wrong bolt into the hole will fuck it completely, so for
your sake I would take the remaining original screw to a bolt
specialist, hardware store or anyone else who can help you out to get a
replacement.

And he should make sure the bolt specialist isn't faking it like you do
*all the time*. Say, how's that proof of your trade qualifications
claims coming along Darren? Look deep into those dark dank depths of
your delusions, I'm sure you'll find them.