View Full Version : 9/16-18 O -ring tool

01-23-2009, 11:14 AM
Has any body ever made the tool to ream the bore and put the 15 deg chamfer prior to tapping. If so I would like to see how you did it also if the tool is available at a reasonable cost commercially.

Reason is I am trying to repair a 5 port manifold on my air compressor , it's old but a good 2 cylinder one sold years ago by Montgomery Wards and I do not know who made it.

Thanks Graeme

01-23-2009, 02:11 PM
Assuming you mean an SAE O-ring port.

I made a small one for 5/16-24 from an 11/32 screw machine drill.I had the benifit of a surafec grinder and spin index to grind the OD of the tap drill step first,then finished the angles by offhand grinding.

There are port forming tools availible,IIRC MSC carries them,but they aren't cheap.

If you just need to do a few I would freehand grind a tool for the 15* chamfer out of an old endmill.

01-23-2009, 02:51 PM
Yes the O-ring port tools are nice if you need to do a bunch. It's a form tool, so that once you have a pilot hole, it does the tap drill, the chamfer and a spot face at one go.

01-24-2009, 12:19 PM
Drill rod, machine diameters, mill cutting edges, harden and temper, hone cutting edges.

You can rough size using various drills and use above as a "Reamer". Used to have to make many "Special" milling cutters from SilverSteel (Drill Rod)

Regards Ian.