Trying to cut 45 Deg. In Aluminum

oskar

Registered
Registered
Joined
Nov 24, 2013
Messages
254
The attached pictures show my set up to cut 2 corners of the 1”x1”x1” long aluminum bar at 45 degrees by 0.250” (first I will do one corner and then flip it to do the opposite corner). I made a template shown in the picture to position the piece in the vise at 45. I will be using a 4 Flute 1/4" End Mill to do the job in several steps. The pictures of the lathe are taking looking at the back of the machine.

The attachment to the lathe is the compound slide and I covert it to a milling attachment. The vise holding the piece is homemade while I’m waiting to choose a proper vise.

The purpose of the 45 degrees cut is an attempt to make a mini QCTP I follow on a thread

Is the procedure acceptable?

Milling 45A.jpg

Milling 45B.jpg

Milling 45C.jpg
 
I can't see if you have support behind the piece, but I greatly prefer to have a part resting against another surface to reduce the risk of movement. I would also consider choking up on the endmill to reduce the potential for flex. Neither is likely critical, but that's what I would do.

Is that a Sherline?
 
This is a mini Taig

You are right, I should have the piece resting at the back, now because of the template is about 1/8" away form the back

Thank you
 
Thank you Tom

I was thinking if I cut the template in half, that will give me the 45 I need and I can secure the half of the template to my vise to have the 45 I need. This way the work piece back will be resting on the vice wall at the back and at the same time will be at 45 due to the half template.

BTW as mentioned before the end mill shown on the picture is not set yet. When I start the cut it will be set further into the chuck.

Nicolas
 
The length of flute should only be long enough to make the cut with some clearance to the part and your collet.
In your case I would only have 3/8" sticking out from the face of your collet!!
 
The length of flute should only be long enough to make the cut with some clearance to the part and your collet.
In your case I would only have 3/8" sticking out from the face of your collet!!

The end mill total length is 2.5” and the length of the flute only is 3/4". If I leave only 3/8” of the flute out it means part of the flute will be inside the collet. Had the impression that it’s not a good practice to have the flutes inside the chuck (might damage the collet)

Does it matter if the flutes are inside the chuck?
 
The end mill total length is 2.5” and the length of the flute only is 3/4". If I leave only 3/8” of the flute out it means part of the flute will be inside the collet. Had the impression that it’s not a good practice to have the flutes inside the chuck (might damage the collet)

Does it matter if the flutes are inside the chuck?

I'm no professional machinist, but I think your assumption is correct and that clamping on the flutes would not be good practice; it wouldn't even be possible if the shank and the flutes were of differing diameters as they are on some end mills. I would chuck it in the collet fairly deep, but leave a small margin to account for a radius between the shank and flutes (if any).
 
I agree with T Bredehoft to leave the template in place as is. It will keep the work piece from sliding backward or sideways. If it tilts back from end mill pressure near the top of the cut, your vise isn't nearly as stout as it looks. ;)

Tom
 
Back
Top