Nyone had any isssues drilling 12.5mm into a 3/4" blank?

[philb]

Hi,

Made a couple of jr.gents kits out of 3/4" stock, had no problems with the drilling. Today the I managed to blowout a Kingwood and 5 BOW blanks all with the 12.5mm drill bit. Then it went straight through a Zebrano one exactly the same size!

Ive tried changing the speed of the drill, how fast i actual go through drilling, how tight the wood is clamped! Whatever didnt work!

Just wondering if anyone has any tips, or was it just a bad day in the workshop!

Drilling in a vice, on a benchtop drill if that helps?

PHIL

 

[marcruby]

If you're convinced that its not a sharpness or speed issue thern the next thing to try is bracing the blank with waste wood. Assuming you can drill straight this should solve the problem. Then all you have to do is turn the waste off. I guess the final truth is that sometimes the wood just doesn't want to be a pen.

Marc

 

[hughbie]

whenever i drill the 'larger' holes....i start with a pilot hole...i'll drill that hole all the way through then follow it up with the larger bit.......and i ALWAYS drill through into a waste board......never open ended......at least it works for me

in fact, i drilled a 12.5 and a 10.5 just this morning for a Jr. Gent for the wife....no problems

 

[mrcook4570]

Do not let the drill exit the blank. Cut the blank longer than necessary, drill, then cut to expose the hole.

 

[sbell111]

I've drilled some with no issues. I've also destroyed several blanks.

 

[philb]

Yeh that seems to be the problem with the 12.5mm drill and the 3/4" blank. Sometimes it will glide through other times it pops!

Maybe an ultra sharp drill and some waste stock, or not going all the way through is a better option!

Cheers for all the advice guys, will give it a go tomorrow in the workshop!

 

[Chris Bar]

I always drill all-the-way through the blank, use a sharp brad point bit, and go very slow the last length equal to the diameter of the bit. I then cut off the end of the drilled blank to remove the blowout and then match the remaining blank length to the tube. If it is long enough, I use it; if not, I throw it away and drill another blank; the blank sellers love me :wink:. Actually I have had no blowouts after switching to brad points and going v-e-r-y slow. You can see a little round wood disk (the hole end) drop out the bottom if you drill slowly.