View Full Version : Mills and Drills Hollow Mills?

Chris Padilla
12-19-2012, 8:40 PM
I found these:


I'd like to find a place with a few more sizes on the smaller side.

The 3/32" x 5/8" *might* work but I'd like to find more options.



Bruce Page
12-19-2012, 9:47 PM
I don’t think I have ever seen them much smaller than that Chris. When I worked at Los Alamos they had several sets from very small, .250 OD to large, 2.5 – 3.0” OD but I believe they were all custom made.

Chris Padilla
12-20-2012, 2:09 PM

I wonder if I could simply have a regular old end mill drilled out to the diameter I want?


I see the 3/8" diameter one here for under $10. I need to mill down some aluminum to create a longer nozzle on a part whose nozzle broke off too short. Thankfully, it has plenty of room/material to mill down further to create a new nozzle.

Chris Padilla
12-21-2012, 12:25 PM
Here are a couple of shots of the device that needs a new nozzle cut in. The outer diameter of the nozzle needs to be 5/32" so that is the hole size of the hollow mill that I need. The outer diameter of the hollow mill needs to be at least 13/32" but going up to a 1/2" is fine and gives me clearance to other objects in the way.

This silver aluminum box is a small heater for a steam mop. The nozzle for one of the tubes is crazy short...very strange design. The manufacturer had to use some kind of caulk or gasket seal to ensure the tube stayed on and when I broke the seal to unclog the device, trying to get it resealed was futile. However, there was enough bulk of aluminum there that I thought a hollow mill of some kind to lengthen the nozzle should work.

A new mop is $100...I'm hoping to fix it for far less than that but now finding the tool size I need is proving difficult. SIGH


Bruce Page
12-21-2012, 5:26 PM
I don't quite understand what you have going on there but you can't easily drill a endmill, they typically have a hardness of about RC65. I have drilled out taps before but it is a tedious procedure using a specially ground carbide drill or ball end endmill, lots of oil, and a milling machine. You could have it EDM'd (Electro Discharge Machining) but it would cost you.

Dave Verstraete
12-21-2012, 6:32 PM
It is possible to open up the I.D. on the hollow mill in that link. I could do it with one of our wire edm machines. You would have to get it to me in Michigan , though. I might question how you will hold the workpiece still while milling it?

Adam Neat
12-21-2012, 11:52 PM
Why not drill it out, tap with pipe threads and thread in a hose fitting...something like this http://www.grainger.com/Grainger/PARKER-Male-Connector-2GUP4?Pid=search

Chris Padilla
12-22-2012, 1:14 PM
Now Adam, that is a mighty fine idea. I will look into it!!