Trouble with AA blue and white and red and white?

[TonyL]

Hi Folks:

I am struggling with AA blanks for the first time. I cracked one set of blue with white stars while drilling the hole, and them did the same thing with the red and white (driiling on my lathe).

Then I had my friend drill another set for me (he did it fine on his drill press), then I blew both blanks while using my carbide finish tool on both!

I am TBC with LLinez bushings.

Are these PSI blanks known to be extra brittle? These were the first AA blanks that I have blown after making 80 pens in less than 4 months.

I though these were a no-brainer.

Thank for reading!

Best,

Tony

 

[mjsix1]

Tony,
I have had success with the Stars and Stripes blanks I received from PSI. Here's what I did after reading several articles about dealing with these blanks. 1st, I bought a drill bit specifically for drilling acrylics. These drill bits have a sharper point and tend to cut thru the ends rather than punch thru them. I also drilled at about 800 RPM and did small plunges at a time to keep heat to a minimum. After each plunge (maybe about 1/2 inch), I would back out the bit and check it for heat. If it felt too hot, I would wait a few minutes for it to cool, then proceed. I also drilled on the lathe to get as close to dead center as possible. Additionally, I left the blanks about 1/4 inch longer than the tubes, leaving me a little meat in case I did have a chip out from the drill. I trimed the blanks with a sharp trimming barrel on my drill press. Before gluing in the tube, I back painted the blue stars tube because the blank is somewhat transparent when turned down. After gluing the tubes, with CA, I mounted them with bushings and turned them round with whatever sharp tool was available, taking light cuts with each pass. Once round, I switched to a sharp skew to finish the turning - again taking light passes. From there it is sandpaper to 600 grit, and then wet sanding with MM thru all 9 pads. I think the keys are: 1) use a bit designed for drilling acrylic; 2) don't let the blank get hot; 3) cut with sharp tools and use a skew as you get closer to final diameter. So far, this has worked for me.

 

[TonyL]

Thank you. I just successfully drilled both barrels. And waiting for paint to dry.
I have made close to 75 AA pens (AA from at least 6 merchants, but I have not had to be any more careful with the first 74. This is my first stars and stripes blanks (well my second LOL). Thank you for sharing your process with me!