Reaming a 6 inch deep .261 hole on a CNC mill.

[mike561h]

Hey friends,

 

The reamer size is .261. anyone have any tips.

Its a bummer if the reamer locks up half way thru. I will be reaming out .0055 a side. 6 inches deep. 300 RPM 3.0 IPM. Coolant. Any tips would be appreciated. I hate these stinking deep holes.

[Guest]

I'd really consider gun drilling that.

[Zoober]

Material?

[mike561h]

17-4 stainless. I was going to drill 3 inches then flip and drill 3 inches. I'll leave .015

so the reamer picks up the miss match in the middle

[Mgrenier]

What is the tolerance of the hole? I would also consider using a gun drill for this if the tolerance allows for it.

[taperlength]

Maybe a carbide reamer and some real oil.

[X-L Engineering Corp]

We Gundrill holes with .0006 tolerances

[Mike Whitten CAD/CAM Contractors]

If you are going to ream it, the first thing I would do is call Hannibal Carbide. I have had great support with them in the past and their reamers are very good. link

 

Mike

[mike561h]

We had 1 of our large vendors gun drill the 5 before. Some were out of concientricity .015. They gave us this BS song and dance that we should turn the OS after they gun Drill. BS.

I heard form a very experienced gun driller that you set you pressure on your drill and when it alarms out you resharpen the drill. He also said he held .003 and the part must be to size when to you do it. Why make more work on a lathe to offset your tailstock to make it come in concientriciy wise. These guys just ran the drill thru. hec I could have done that.

[X-L Engineering Corp]

Well their are good Gundrill shops and their are not so good Gundrill shops. Most shops say that they can only hold .001 per inch on run out. If that’s not good enough you need to find a shop that will work with you. We ended up buying our own Gundrill because on some jobs that wasn’t good enough.

[Guest CNC Apps Guy 1]

Pfffffttttt, that's only 23x Diameter. That's a cakewalk with the right drill. :cough: Titex :cough:

 

I don't eeeeeeeven consider a gundrill until I get past 30x Diameter.

 

I'd drill that all day every day that ends with "y".

 

You WILL need Coolant Thru though to pull it off.