What Are These

[Bob Korves]

I think in the die business those are called core pins, and yes, the threads are for extracting them and the spiral OD's are for using them in blind holes.

 

[TOOLMASTER]

dowels for glueing metal plates together ;-)


pins that need constant lube

 

[turnitupper]

dowels for glueing metal plates together ;-)


pins that need constant lube

That is just plain silliness, everyone knows that WOODEN dowels are used to join metal, just as METAL dowels are used to join wood.
John

 

[pineyfolks]

If they're long enough and you have a 1.000 and 30mm sizes you could use them to lap scope rings.

 

[aametalmaster]

Tool and Dies makers use them in stamping dies. They use a slide hammer to remove them...Bob

 

[Billh50]

Yep. They are pull dowels. And the spiral is so they can be seated in blind holes. The spiral allows air to escape so pressure is not built up as the dowel is pressed in.
Home / Steel Pull Dowel Pin
Steel Pull Dowel Pin

MSC #: 64137391
Holo-Krome 5/16x3/4inches Alloy Pull Dowel Pin 04022
Brand:
Holo-Krome
Mfr Part #:
04022
In Stock
Price:
$4.35


5/16 Inch Pin Diameter, 3/4 Inch Pin Length, No. 10-32 Inch Thread, Grade 4000, Spiral Vent Pull Out Dowel Pin

 

[TOOLMASTER]

View attachment 128603
That is just plain silliness, everyone knows that WOODEN dowels are used to join metal, just as METAL dowels are used to join wood.
John

http://www.woodcraft.com/Images/products/600/50M31.jpg

 

[turnitupper]

Toolmaster,
those spiral wood dowels are like hens teeth here on OZ and shipping from the US is ridiculous even if our quarantine laws would allow them in.
Would definitely not be allowed if they were made of DOGWOOD (J. Depp reference).
John.

 

[David VanNorman]

The threads are to expel traped air when driving in blind holes.

 

[Chippy]

The threads are to expel traped air when driving in blind holes.

I would imagine the groves are for releasing the vacuum when removing them as well.