Accuracy...

Meaningful discussion outside of the potato gun realm. Projects, theories, current events. Non-productive discussion will be locked.
User avatar
mark.f
Sergeant Major 4
Sergeant Major 4
Eritrea
Posts: 3638
Joined: Sat May 06, 2006 11:18 am
Location: The Big Steezy
Has thanked: 58 times
Been thanked: 61 times
Contact:

Donating Members

Tue Sep 12, 2006 8:49 pm

Being tired of measuring things with a crescent wrench and a ruler, I decided to invest in some good calipers.

I just bought a decent pair off McMaster, (± 0.001" accuracy, 0-4" range...), and they weren't at all expensive. My friend was trying to talk me out of it because he said they cost all of this money. But, I needed them anyway for an upcoming project so I figured I'd knock em out while I could.

Most of their use is just gonna be normal stuff like for Chemistry, (getting the lowest percent error out of everybody in the course), and various machining endeavors. But, for spudding, I guess they would be useful for making piston valves, moving parts, and maybe measuring bores to make sure they'll be the right size before I buy em!

Another thing I'm curious about is the difference in bore between 2-1/2" ASTM D2466 pipe and 2-1/2" conduit pipe. I've heard the I.D.'s are different before, but I'd like to see. The Home Improvement near me has 2-1/2" conduit, and I've got the ASTM D2466 on my tennis ball cannon.

That's it! Besides boilingleadbath and all you other people with access to metal shops out there, anybody else have some calipers or micrometers? Wanna form a Metrology club? :roll:
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6572
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Tue Sep 12, 2006 9:03 pm

Building my cannon with a 25' tape measure, but i do have 2, 1" frame micrometers, 2, i don't know what kind/make of venear calipers, much like you discribed, 2, feeler gauges, spark plug gaper, 2, squares a 3' one and a 1'
User avatar
sgort87
Corporal 5
Corporal 5
Posts: 994
Joined: Sun Sep 18, 2005 10:32 am
Location: Lockport, Illinois

Donating Members

Wed Sep 13, 2006 12:57 am

Never underestimate the power of eye-balling! But yes, calipers are nice to have as well.
User avatar
mark.f
Sergeant Major 4
Sergeant Major 4
Eritrea
Posts: 3638
Joined: Sat May 06, 2006 11:18 am
Location: The Big Steezy
Has thanked: 58 times
Been thanked: 61 times
Contact:

Donating Members

Fri Sep 15, 2006 5:54 am

Just got em in last night. So far, I've just been measuring bullet calibers.
User avatar
frankrede
Sergeant Major 2
Sergeant Major 2
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Has thanked: 1 time
Been thanked: 1 time

Fri Sep 15, 2006 8:57 pm

sgort87 wrote:Never underestimate the power of eye-balling! But yes, calipers are nice to have as well.
That was a good one.
Post Reply