What Did You Buy Today?

[Winegrower]

what was the temp ?
standards are made at a certain temp, and if you are not at that temp... wellllll you get variation.

This digs a rabbit hole, which for me is not productive, but anyone else is welcome to pursue. Start with the pin and the hole…if you heat both, is it easier or harder to insert the pin?

 

[woodchucker]

This digs a rabbit hole, which for me is not productive, but anyone else is welcome to pursue. Start with the pin and the hole…if you heat both, is it easier or harder to insert the pin?

I'm not understanding. you realize that JoBlocks have the same issue. They require the same temp.if you are not in temp, the readings will be off.
are you thinking well, the standard and the caliper are the same temp so should be ok? if the standard expands by 2 tenths and the caliper by 2 tenths, you are off by 4 tenths... since the standard is pushing out, and the caliper is pushing toward the void so you need to open it more.

 

[Winegrower]

since the standard is pushing out, and the caliper is pushing toward the void so you need to open it more.

Woodchucker, with all due respect, you need to think about this harder.

 

[matthewsx]

Clearly not "empty'!

At least "EMPTY" of ordinance....

John

 

[woodchucker]

Woodchucker, with all due respect, you need to think about this harder.

OK... DAMN it I got nothing..

So your saying that temp has nothing to do with a standards measurement?
Why because your mit standard measured correct?

 

[Winegrower]

I think you are figuring this out, Woodchucker. The thing is, the pin and hole expand/contract at the same rate, assuming roughly similar materials, so it’s the same fit. The standard and the mic also expand or contract at the same rate, so the reading stays the same. That the gage blocks/mic read correctly is a good sign that the mic is good.
Obviously the absolute dimensions change with temperature, so if the part is red hot, and the mic is room temperature, the reading will be higher.

 

[woodchucker]

not true, the casting caliper shape C is different than the anvil's rod. different materials, different rate.. maybe close
The standard is closer to the anvil's rod..

But I'm going with what I know.. that the blocks are calibrated at a certain temp. At a different temp they will be slightly off. Every metrology book and the certificate itself says something to that effect.

 

[Janderso]

Mini mill bits $20

View attachment 402827
Came in this cool ammo can
View attachment 402828

John

When the ammo box is full do you need to change the stencil?

 

[Jim F]

When the ammo box is full do you need to change the stencil?

I have 2 of those 20MM cans I keep moving or tripping over..........

 

[Jim F]

I have 2 Jacobs Super chucks in the supply chain, an 11 and an 8 1/2.......
also a Phase 2,large dial 2' reading dial indicator.
Received the 3 Federal TDI's yesterday.