Drilling a Straight Hole.....Yikes

[jbyrd24]

Hi all.
Never thought I'd have to post this.
I have been using a Hut Pen Drilling Jig
when drilling my blanks. I can start in the dead center
and end up quite a bit out of center on the other side.
I drill slowly and clean the bit as I go. Would a pilot
hole help or is there simply something I'm doing wrong.
I attempted to turn a tapered pen yesterday and by the time
I got to the small end the blank blew. Any help would be
greatly appreciated.
Thanks
Bryan

 

[ctEaglesc]

Have you checked your Drill press table lately?
Is the bit sharp?
Either of these 2 things could cause a bit to wander or drift.
Even the grain of the wood can do it.
Easiest way to check the DP table is to chuck a peg board hook in the chuck.(The long type they hang single bubble pack stuff on in stores.
This will off set it from the center of the table.
If you don't have a hook like that you can bend a coat hanger with an off set almost to the edge of your DP table.

Raise the table so you have minimal clearance (but some between the end of your (hook) and the table.
Revolve the spindle by hand and see if the table is perpendicular to the bit.
Adjust the table as necessary.
The DP could just have some run out.
The bit may be defective.
I just re read your post and you mentioned a jig.
See if that's out of whack.
If you are drilling with a hand drill you're on your own.

 

[KKingery]

If you're using a drill press - you gotta make sure the plate is level front to back & side to side. I was using an old drill base I had for many years, and had the same problem. Turns out the shaft was bent that went up and connected to the pulleys.

 

[Rifleman1776]

Bryan, everything has to be absolutely square. The little bits of wood we work with do not allow any margin for error. I had the same problem until I rechecked the square of my drill press table/spindle, it was off by just a skooch. But a skooch for a pen blank is a whole whoop. I have the best luck with brad point bits. Back out frequently to clear chips and let both blank and bit cool. The harder the wood, the more heat. Stabilized and special woods, like dymondwood build up a lot of heat and that alone can blow a blank. I drill at slow speeds. Others will respond saying to use high speeds. Their theory is that high speeds produce less heat. My theory is that slow speeds produce less heat. [8)] Now, I probably have yout completely confused. Shouldn't do that on Sundays. []

Originally posted by jbyrd24
<br />Hi all.
Never thought I'd have to post this.
I have been using a Hut Pen Drilling Jig
when drilling my blanks. I can start in the dead center
and end up quite a bit out of center on the other side.
I drill slowly and clean the bit as I go. Would a pilot
hole help or is there simply something I'm doing wrong.
I attempted to turn a tapered pen yesterday and by the time
I got to the small end the blank blew. Any help would be
greatly appreciated.
Thanks
Bryan[]

 

[ctEaglesc]

I have played around with belt speeds,and this is what I can surmise.
Given the premise that the drill bit is sharp, the less time it is in the wood the cooler the wood ,or antler will wind up.
I don't do much plastic.
I don't use a lot of brad point bits.I have a couple and when the get dull I will sharpen them on the Drill Dr. and turn them into split bits.
I have had the best luck with those.
To each his own.

 

[jbyrd24]

Thanks all. I'll see how square I'm drilling. I'm using
a small Craftsman drill press Jake and I bought recently.

Bryan []

 

[btboone]

I had that happen due to the grain of the wood once. As the others say, the rpms aren't as important as letting the drill eat at its own pace. Pushing the feed too hard for the given rpms will cause the drill to wander. Clear the chips a lot. Check the sharpness.

 

[Old Griz]

Certain highly grained woods seem to make the bit travel... on some of these woods I drill the blank on the lathe using my Nova chuck with spigot jaws to hold the blank and a drill chuck in the tail stock.. it is slower than using a drill press but a lot more accurate.. and since I usually do a couple blanks at a time not all that much slower... there may still be a bit of drift, but no where near as bad as in a drill press for some reason...
This happens a lot on blanks that are angle cut... cross cut blanks do not seem to have this problem..

 

[Mickey D]

I also use my lathe and find I have better results. I've wondered if anyone else did.

 

[ctEaglesc]

Originally posted by Mickey D
<br />I also use my lathe and find I have better results. I've wondered if anyone else did.

I have made some pens and pencils that use a joining center band to press fit the sections together such as the Power Point line by PSI.
I drill the blank in one piece and use a single tube.
I have found it more accurate to drill longer pieces this way.The blanks are approxmately 4" long.The tubes I believe measure out 3& 7/8ths.
It would be nice to have a longer drill bit but I can normally get them fairly centered.
There isn't much drill left in the chuck.

<br />

 

[leehljp]

Being new to pen turning (and turning in general) I have run into my share of problems that are different from normal woodworking. But two areas of help from woodworking so far have been having sharp tools and being able to drill a straight hole in a narrow piece of wood. That comes with experience. So keep trying! The experience that I do not have - has taught me to practice, practice, practice and listen to the guys on this forum. Currently I am having trouble getting the right finish, but with some of the notes in past posts, I am learning.

 

[Gary]

I had the same problem until I got my drill press squared (perpendicular) with the bit.

 

[jdavis]

CHeck for squareness and correct drill speed. Speed should be 800 to 1000 rpm for 7mm thru 3/8 bits.
Even new drill presses are any machine can be not square. Good luck and have fun.

 

[DCBluesman]

Remember when squaring your table that it must be squared to your quill travel both front to back and side to side. Table can be off in just about any direction imaginable.

 

[JimGo]

I think everyone has pretty much hit it on the head. But, just to be redundant, here's the approach I used:
1) Make sure the <u>bit</u> in the drill press is perpendicular to the ground
2) Make sure that the four sides of the blank that can be are as close to paralell to the drill bit as possible

I did this using a level; I checked the bit first by using a level. Then I put the blanks in a vise on my drill press table. I didn't pay much attention to the angle of the table or the vise itself, since the vise I used did not have a "V" notch in it to hold the wood perpendicular (it would be much easier if I had one of these, since I would only have to set up the vise once per drilling process). Each time I put a blank in the vise, I made sure (again, using the level) that the sides of the blank were perpendicular to the floor (i.e. paralell to/level with the drill bit). I then just drilled slowly (i.e. not a lot of pressure on the drill press), and wound up with what I thought were pretty good, straight holes.

Unfortunately, the vise I used didn't mount properly to my drill press, so I had to return it. I then tried to drill some blanks this weekend "by eye", and that was a mistake. I tore right through the side of one of 'em (thankfully, it was Purpleheart, and I have more of those blanks), and cut another so close that I lost it on the lathe when I went to turn it down. My birthday is coming up, and I'm hopeful that there will be a self-centering vise in one of the boxes so I don't repeat this weekend!

Good luck!

 

[Carole in VA]

Assuming all of the above regarding the squareness of your drill press, be sure your blanks are square and that whatever clamping system you are using to hold the blank keeps it square to the drill.

 

[btboone]

Another thing to watch for; start the hole very slowly with very light pressure so the drill can find its own center. If the hole starts slightly off center because the drill walked a little, the hole will get progressively worse as it gets deeper because the bit is forced to take a curving path.