Milling machine end mill bit help

[Dlb21964]

Hi everyone,

I have a PM30 I use for milling out stocks and various other machining projects related to custom rifle building.

Which brings me to my question-what end mill do I need to remove bedding material (Devcon) all the way into the corners but not remove the material above it?

I’ve attached a picture of the area I’m relieving. I don’t want to enlarge the sides, but I want to mill down the flat area, which means I need to relieve it all the way into the corners.
Thanks in advance!

 

[GeneT45]

I'm not sure I really follow your question. It looks to me like a regular, straight endmill is all you need. Probably carbide, the glass in the stock and/or bedding compound will eat HSS cutters in short order.
If you're trying to undercut the 'shell' of the stock you need a woodruff or t-slot cutter. If it's just a tiny undercut you might get by with thinning the shank of a standard endmill on a grinder (using some sort of spin fixture).
HTH,
GsT

 

[homebrewed]

A so-called keyseat end mill might do it: Like this. As indicated above, also called a Woodruff cutter.

 

[francist]

Not sure that this will be short enough but you might be able to find a similar style that may work. Essentially a flush trim bit but the bearing is above the cutting flutes rather than below. The bearing would follow along the sides of your existing pocket and allow you to mill deeper but without cutting into the existing sides of the pocket.



-frank

 

[pontiac428]

Is that a polymer stock? Without a rear column or any type of bedding block, there's no need for bedding the bottom metal. Just remember when milling your pocket that every bit of extra depth you mill is moving the mag's feed lips closer to the bottom of the bolt, so there's a finite amount of space there, if any. Hunting rifle, or are you playing PRS gun games?