Making Star/Magma type sizing dies

KeithB

Resident Half Fast Machinist
We're running some blank Star/Magma type dies to replenish our stock and thought it might be interesting to post a video. This uses a tool holder setup with three boring bars, two of which have grooving tools and one is a turning/facing tool. They are bolted firmly to the cross slide and do not need to be changed for the production run. A cutoff tool is mounted in the Aloris QC toolholder. All we have to do is press the RUN button 5 times during the program. The coolant stays on, coming through multiple nozzles, and the collet chuck is air operated, so we can run these all day with no fatigue.

We set up the TL1 lathe to run the second operation at the end of the work day today, so we will backface and drill the center hole in these tomorrow. I will post a video of that later.

 

Brad

Benevolent Overlord and site owner
Staff member
Interesting to see how the parts are made.
If you don't physically remove the part after cutoff is there a way for the machine to keep the cutoff parts separate from the swarf?
Will be interesting to see the final facing and drilling. I assume it requires a manual placing of parts in the chuck.
 

KeithB

Resident Half Fast Machinist
We usually catch the parts with a hand-held section of plastic pipe that we put over the piece right before the part gets cut off. We tried making a little basket as a parts catcher but it caught about as many chips as it did parts. The apprentice wanted to grab the part and hold it up to show it off at the end of the vid so that is why he used his hand.

The body of a Star die is right under .750" so we put a 3/4" collet in the chuck with the bottom of the top end of the die against the face of the collet. Makes for a positive stop and accurate lengths. You'll see when I post the next video.
 

Brad

Benevolent Overlord and site owner
Staff member
What kind of life does the drill have for this type of operation? It is getting dull.:)
 

KeithB

Resident Half Fast Machinist
We ran 80+ pieces w/o needing to change/sharpen drill. It was getting dull enough at the end that it would need to be touched up before running too many more pieces. But we already ran a 90+ piece batch of Lyman dies with the same drill a couple weeks ago so I can't complain about drill life.
 

Brad

Benevolent Overlord and site owner
Staff member
Even if the bit was 5 bucks at 100 parts it is 5 cents per part. In your case more likely 2 cents per part.

That sure is a bunch faster than my manual lathe.
 

KeithB

Resident Half Fast Machinist
It's a good quality HSS drill. The material is 1144 ("Stressproof") steel which machines very nicely. Using coolant and peck drilling to keep the flutes clear of chips makes for optimal drill life. It sure is faster than my manual lathe also!
 

fiver

Well-Known Member
I kind of hate to ask this.
but couldn't you use the CNC machine to sharpen the drill bits.
 

Brad

Benevolent Overlord and site owner
Staff member
I kind of hate to ask this.
but couldn't you use the CNC machine to sharpen the drill bits.
Sharpening bits requires a grinder. It also means little bits of fine abrasive get thrown off. Not good in a precision machine.

Bits are often ground by hand, if you are good enough, otherwise there are fixtures that hold them in line with a small grinding wheel to sharpen them.
 

fiver

Well-Known Member
I have always done them by hand.
I just thought that as precision as a cnc is it could put a consistent precision face on a bit or series of bits pretty quick with some type of cutter.
 

KeithB

Resident Half Fast Machinist
I’ve got a drill doc for sharpening drills but generally do it by hand. Have a tool/cutter grinder in storage, looking to get it running after we move to new shop in a few months. Then we can make many of our own tools. No real way to sharpen drills on lathe, wish I could!
 

Pistolero

Well-Known Member
Drill doc does a really good job. Diamond grinding wheel, and does the correct, oddball
things that you need to do, and accurately, to get a proper drill bit. I can do the larger ones
pretty well by hand, but little ones are tough. And the really small ones, I buy a new one when
they are done.

Bill