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Cast red brass smoothness

Posted: Fri Jul 25, 2008 2:11 pm
by Kobl
I'm ordering some brass nipples off McMaster for my newest cannon and I need to know whether or not cast red brass nipples are smooth on the inside.

Anyone have any experience?

Posted: Fri Jul 25, 2008 2:22 pm
by SpudFarm
the brass nipples we get in norwas has something that can look like a seam on the inside..

if you want to set a piston in there - go4it

Posted: Fri Jul 25, 2008 3:00 pm
by Kobl
Well, its just that it needs to be SUPER smooth because I'm using rubber rod as the piston which is (hopefully) exactly 1 inch in diameter and the inner diameter of the nipple is 1.049 inches so if its rough at all it won't slide.

Posted: Fri Jul 25, 2008 4:25 pm
by Eddbot
my bad...got confused...

Posted: Fri Jul 25, 2008 4:44 pm
by Kobl
it's brass...

specifically, McMaster # 4568K221

Posted: Fri Jul 25, 2008 4:47 pm
by iknowmy3tables
I don't have experience with mc master ones, but I'm sure thet are, waht size are they maybe you can bore it with a drill if it isn't

Posted: Fri Jul 25, 2008 4:49 pm
by Kobl
It's 1 inch.

Posted: Fri Jul 25, 2008 4:57 pm
by SpudFarm
no i can try to get a pic of the inside of one of the nipples we get.

Posted: Fri Jul 25, 2008 5:08 pm
by Sticky_Tape
These are the threaded ones right? The ones I can get at home hardware are smooth on the inside yours might be different but I remember someone here said they use them (The brass nipples) for a piston housing because the insides of them are smooth. I believe that the one you are going to order is the same way.

Posted: Fri Jul 25, 2008 5:19 pm
by Kobl
I hope you guys are right, I'll be ordering my stuff from Mc-M's tonight (maybe).

Posted: Fri Jul 25, 2008 5:40 pm
by SpudFarm
you can use some 1" copper pipe with threaded adaptors on the ends..

Posted: Fri Jul 25, 2008 5:41 pm
by Kobl
It would take up too much room, I'm aiming for a fairly compact design.

Posted: Fri Jul 25, 2008 7:00 pm
by frankrede
Its cast, therefore its safe to assume its not going tp be that smooth at all.
Look in a steel fitting....

Posted: Fri Jul 25, 2008 7:03 pm
by Sticky_Tape
The seam in a steel fitting is a weld line other than that I find that the inside of steal fittings are smooth these nipples are different there isn't a weld line and is smooth right around
frankrede wrote:Its cast, therefore its safe to assume its not going tp be that smooth at all.
Look in a steel fitting....
He never says it is cast it might just be brass pipe cut and threaded.

Posted: Fri Jul 25, 2008 7:08 pm
by Kobl
Hmm, well they're not toooo expensive, so I might as well give it a shot, I'm also really excited about my solid rubber piston. I think I'm going to start a build log for this cannon.