I think I figured something out

[bking0217]

I was looking at the Tru-stone blanks and many of them warn to take great care to avoid blow-outs while drilling. For this reason, I've avoided them. As I thought of them a few minutes ago an idea hit me. As an experiment, I grabbed a spalted sycamore blank and cut off a piece just long enough for the top section of a cigar kit. (Note: I drill on the lathe) I then made a mark on one side of the blank and lined that up with jaw #1 on my chuck. I drilled halfway through the blank, stopped the lathe, flipped the blank (being careful to keep that mark with jaw #1) and drilled the other side of the blank. It worked perfectly. No possibility of blowout because you're only drilling halfway and flipping the blank. YMMV. I'm sure this has been done to death by greater turners than me but I've never seen it before and I thought I would share.

 

[williamcr]

I never thought of drilling blanks that way so I will try it. Thanks for sharing.

 

[Haynie]

I tried that a few days ago but on my drill press. I drilled half way through the flipped lined it up and drilled the rest of the way. My drilling was spot on and blank still blew out. This is some brittle stuff. If I ever do tru stone again, and it won't be any time soon, I will CA a waste piece of wood on the bottom and drill through it. Maybe that will hold things together.

 

[SDB777]

I would think that backing the drill bit out and ensuring the 'flutes' are emptied would keep any blank from coming apart....


What if that high dollar blank isn't completely square on the outside, and then the bit will not cut true and leave the tube slopping around on the blank? How is that better then a blowout....






Scott (thinking out loud) B

 

[Whaler]

I cut all of my blanks long, drill the proper length for the tube + a little and then cut off the waste. Never had a blowout in anything doing it this way.

 

[firewhatfire]

sounds like you are drilling to ast and getting the blank hot to me. I have alot les blowout by taking my time, I also keep my airhose pulled up to lathe and blow blank out as I turn. I dont have to back the drill out as much that way.

 

[gawdelpus]

I always drill my truestones and acrylics in a drill press ,but with a squirt of water from a spray bottle set to"jet" removing the drill bit to clear shavings before it heats up and binds .so lubricates and cools rarely have a problem , I also use quality drill bits well sharpened to reduce friction as well ,heat is the big enemy with these materials . I use Dewalt drills when possible as they have a small centre drill starter and a square end , so as the drill breaks through a small hole is made then enlarged as the main bodyof the drill finishes the hole off, these bits will drill stainless steel plate without leaving a burr on the under side ,so do well on the softer materials we mostly use in pen making ,everyone starts somewhere and finds what best suits their own methodology experience and equipment available to them , Cheers ~ John

 

[Mapster]

I also drill on the lathe and can never get it quite lined up right drilling from both ends... I tend to use more of John's method. For trustone I go a quick few turns of the tailstock, pull it out of the blank, spray a little wd-40, a few more quick turns etc. Only when I know I am getting close do I slow down and with a good sharp bit, and a slow enough feed rate, you should not get a blow out

 

[Rangertrek]

I have drilled many tru-stone type blanks on the lathe and don't have blow out problems.
Drill at the slowest speed my lathe will go, never drill more then 1/4" at a time with out clearing the waste. Use a little soapy water as a lube on the bit. I mark the bit for the length of the blank, at the end go very slow and let the bit ease out the end. No blow outs.