Off Center Holes in Pen Blanks?

[Old Codger]

I have to admit I'm a 'Newbie' to Pen Turning but have turned bowls, boxes, bird houses, kitchen tools, etc. for a couple of years and never had an issue like this... I recently started turning pens and purchased all new pen turning tools (i.e.; PSI Pen Blank Drilling Vise, Pen Assembly Press, required brad point drill bits, blank squaring tools, etc.) and find that 3 out of 5 pen blanks that I drill are centered on the top of each blank but off center at the bottom of the blank so much that I feel the blank is a complete loss! I've checked the drill press to be sure it is square and level and that the drill press is running at the correct speed, stop often and clean out the drilled hole and let the wood cool, etc. yet still find that the majority of the blanks I drill are off center at the bottom of the blank... What gives? The wood I've used is Cocabola, Purple Wood, and Walnut blanks from PSI and other suppliers... Any/all assistance/advice will be greatly appreciated! Safe turning to all!

 

[monophoto]

I don't think you really have a problem.

The hole doesn't have to be exactly centered in the blank. Remember that a finished pen consists of a brass tube with a relatively thin layer of turned wood (or plastic) on the outside. The axis of the finished pen is determined by the axis of your mandrel, and the outside of the finished pen will be whatever you turn it to be around that axis. The fact that when you start turning the blank isn't exactly centered on the mandrel is unimportant.

What does matter is that the hole that you drill remains straight and comes out the end of the blank (and not out a side), that there is enough wood between the exit hole and the side of the blank to form the desired thickness of the pen body around the hole and tube, and that the ends of the blank are milled to be exactly perpendicular to the tube (and hole).

Most of the material that starts out as a pen blank is removed in the process of making a pen - you start by drilling out a fairly large hole that you then glue a tube in, and then you turn away all but about 1/16" of wood on the outside of the tube.

 

[Cmiles1985]

If it's that the hole is OOR, try not using a brad point bit. They tend to wander a bit when they first touch the wood. Also, if you want a perfectly centered hole each time, drill on the lathe. I personally enjoy drilling on the lathe because it's so much faster for me.

 

[ed4copies]

Your problem comes up once in a while, so I have made a couple drawings.

The problem is, nearly always, that your drill press table is NOT perpendicular to your drill bit. In other words, the table is crooked. See drawing one.

To test, make a half a Y as shown, from an old wire coat hanger. Insert the wire into your drill head and turn it BY HAND!! Set it so the wire just touches one point on your table. As you turn the drill head, the wire should touch all the table exactly the same. If it does, your table is FLAT and perpendicular to the drill head. Most likely, your holes will now be straight.

Hope this clears it up!!

Ed

 

[robutacion]

I read the OP question and I was going to reply and I what thinking that I needed to first go into my "Paint" program and draw up something, it wasn't going to the the bent wire trick, that I never heard of it before and I reckon is one of the simplest ways to test the drilling system, that I've heard of so, who ever come up with that idea, he/she is a smart "creature"...!:wink::biggrin:

So, reading through and seeing your post and your simple and clear drawings/diagrams, I was happy to give up of any drawings of other ways to do it, and applaud/support, what you gave us, its good enough for me, and should be easy enough to follow, by everyone else...!:biggrin:

Thanks for that...!

Cheers
George

 

[low_48]

End grain drilling in wood isn't easy, and oily wood makes it worse. Bring the drill out of the wood, A LOT! If the flutes fill up, they will wander more.

 

[Old Codger]

Thanks everyone! Some great ideas that I haven't tried and I will try the 'ole wire' trick to see what happens. Maybe I can salvage a couple of the blanks as they do still have more than 1/16th of an inch of wood left on one end. Thankfully, none have ever come out the side of a blank, but sometimes fairly close. I just hate to loose nice blanks!
Again, Thanks and safe turning to all!

 

[shastastan]

If it's that the hole is OOR, try not using a brad point bit. They tend to wander a bit when they first touch the wood. Also, if you want a perfectly centered hole each time, drill on the lathe. I personally enjoy drilling on the lathe because it's so much faster for me.

I used to have the OP's problem until I read posts like this one. I bought the PSI blank chuck and mandrel saver. I had a pen drill vise, but never could get the holes to come out straight. I tried using a square to make sure the dp table was perpendicular to the bit, but never could get it quite right. Even drilling blanks on the lathe, sometimes the hole is a little off. I think that there's some play in the pen blank chuck jaws and/or the keyless chuck may be slightly off. I went back to my old JT33 today with better results. I find that I really have to back the bit out often to avoid burning. I'm drilling at around 300 rpms. Not sure it that's the right speed to use either. If the hole is a little off, you'll still have plenty of stock to use but it will take a little longer to bring it into round.

 

[Smitty37]

I have a small level....I put it on the table and when it says the table is level it's square to the bit. I also have drilled holes on the drill press come out off center from where they went in....and the next blank and the blank before were perfect. So I think Ed's solution is right on most of the time it isn't always the answer.

 

[ed4copies]

When speaking about procedures in penmaking, I have often said, "This is the way I do it, there are many other ways that may work just as well--if you are using a way that works for you---keep doing it!!"

What I don't say is equally true---there are MANY ways to do it wrong, so one solution will not fit EVERY problem.

BTW Smitty, your level will work fine, as long as your floor is level. If the drill press is standing on a crooked floor, making the table completely horizontal will not result in a straight hole. The coat hanger trick will make the table perpendicular to the drill head, which will result in a straight hole. (unless the bit itself is bent, but that would mean only one size hole would be crooked and more likely it would be oversize, as well.)

FWIW,
Ed

 

[Smitty37]

When speaking about procedures in penmaking, I have often said, "This is the way I do it, there are many other ways that may work just as well--if you are using a way that works for you---keep doing it!!"

What I don't say is equally true---there are MANY ways to do it wrong, so one solution will not fit EVERY problem.

BTW Smitty, your level will work fine, as long as your floor is level. If the drill press is standing on a crooked floor, making the table completely horizontal will not result in a straight hole. The coat hanger trick will make the table perpendicular to the drill head, which will result in a straight hole. (unless the bit itself is bent, but that would mean only one size hole would be crooked and more likely it would be oversize, as well.)

FWIW,
Ed

In my case when the table is level it is also square with the drill. I established that when I originally set the drill press up.where the drill is sitting the floor IS level, the stand table the drill press is on IS level and parallel to the floor so when the drill table is level it falls in.


My main point is that I have had one blank give me a perfect hole, the next be not streight and the next perfect again. I always thought that some how I was somehow getting the blank into the vise on a cant ot that the blank was a different sizes on the ends...they are often not perfectly square and a straight hole will seem to be off.

 

[Old Codger]

Ed...Thanks for mentioning the fact that my garage floor 'may' not be level thus throwing my drill press off... Duh! Should have thought of that myself and I WILL certainly try your method of checking to see if my drill press is level to the turning.

 

[low_48]

I have a small level....I put it on the table and when it says the table is level it's square to the bit. I also have drilled holes on the drill press come out off center from where they went in....and the next blank and the blank before were perfect. So I think Ed's solution is right on most of the time it isn't always the answer.

The only way the method of checking is correct, is if the quill is plumb. Just checking the table means nothing.

 

[fisher]

I had issues with the Center Hole with the PSI Blank Pen Holder for Lathe.Had to make the Jaws equal on both side's.Then all corrected.The Jaw's were a Bit off Center

 

[plano_harry]

If the table shows square to your chuck like Ed suggested with the coat hanger, I would take a look at your vise. You didn't specify if you bought the $30 toggle lever economy or the $50 centering vise. If you want to check the vise, get a transfer punch that is large enough for the vice to grip, while small enough to still fit your chuck - if you can do that. Chuck the punch, lower the spindle to clamp the punch in your vise, raise the vice slightly off the table and rotate the chuck to see if the clamping face of the vice is square with the table. That is how I center my vice to the chuck before I lock it down.

 

[Tom T]

All really god stuff.
I found all this to also be the case. After the above got me more on track, I still had some lesser issues with the tube not drilling straight. This is what I did and now things are very good. Not perfect.

Two things happened that made it the worst problem for me. 1, the pen blank was not square in the holder on the drill table. I found I had to push down on the top of the blank and then close the clamp on the blank holing vice. Then feel that both sides were level on the pen blank and the top of the vice.
2, was I was pushing to hard on the blank with the bit. Or call it the drill press handle.
Very light pressure really light. When I was in a hurry, and when am I not? it cause the bit to skew of to one side. Side though also. I cut with a wood bank on the floor of the vice and drill all the way through my blanks. Many will say to drill short of the end and then cut the blank. This is probably a better way, but I lose very few blanks the way I do it. If the vice is to tight on the pen black. The black can tend to crack because of the pressure. So I always use tight but not over tight.

 

[Sawdust1825]

I went the same route as Shastastan and couldn't be happier with the blank chuck arrangement. I feel it is the only way to go. You can get the chuck for not much more than the cost of a good blank vise on Amazon. Depending on the blank you start with there will always be a little bit of a tendency to go off center on the end. As for the wire method of squaring your table the concept is right but I prefer a dial indicator sweeping as large of a diameter as possible. The larger the diameter the more accurate you will be.

 

[Penburst]

I've had a problem with the inlet or outlet of my drilled holes being too large. I've tried doing a "starter hole" with a small stubby bit in hopes that this small bit will remain very rigid and set a good starter hole for the final, larger bit. I avoid brad point bits and remove the bit often to keep it from clogging up and to avoid burning. I stop the lathe each time just before withdrawing the bit to avoid possible enlarging of the hole inlet as the bit "wobbles" just near the inlet. If I still get enlargement of the hole inlet or outlet, what could be the problem?

 

[shastastan]

I've had a problem with the inlet or outlet of my drilled holes being too large. I've tried doing a "starter hole" with a small stubby bit in hopes that this small bit will remain very rigid and set a good starter hole for the final, larger bit. I avoid brad point bits and remove the bit often to keep it from clogging up and to avoid burning. I stop the lathe each time just before withdrawing the bit to avoid possible enlarging of the hole inlet as the bit "wobbles" just near the inlet. If I still get enlargement of the hole inlet or outlet, what could be the problem?

I might really be off on this....but, I've noticed that the tubes seem to be looser in the blanks than in the past. I've been buying most of my kits from PSI. I really like that their tubes are already "roughed" up. I've tried different makes of drill bits and it doesn't seem to matter. I have to wonder if the tubes are being made just a micro bit smaller? I use the thick CA glue liberally and that seems to work okay.

 

[fantasticalwoodworks]

I have a psi pen drilling vise that i have been useing for years trouble is that every time you want to use your drill press for another project you have to set it up again so i recently bought a nova chuck with the pen drilling jaws to drill on my lathe It works great and no set up every time the only problem is that it will set you back about $ 200.00 for the complete set is it worth the extra cost you decide what your time and material is worth Happy Decisions LOL

 

[Old Codger]

Hi Guys!!! I've tried all the suggestions and sage advice from more experienced pen turners but finally gave up and switched to drilling pen blanks on my lathe using a new Nova Pen turning jaw set... Sooo far after several pen blanks it's turned perfectly and I'm super pleased!!! Regrettably, I feel I 'wasted' over $50 on an expensive drill turning jig that has not served me well... I wish I had gone with my 'gut' instinct and gone with the Nova Pen Turning Jaw set at the beginning and put the $50+ buying nicer pen blanks, etc... Go with the Lathe pen turning jaws vice the drill press pen turning jig!!! P.S.: Anyone want to purchase a 'slightly used' $50 drill press pen turning jig??? ;>)

 

[sbell111]

I've had a problem with the inlet or outlet of my drilled holes being too large. I've tried doing a "starter hole" with a small stubby bit in hopes that this small bit will remain very rigid and set a good starter hole for the final, larger bit. I avoid brad point bits and remove the bit often to keep it from clogging up and to avoid burning. I stop the lathe each time just before withdrawing the bit to avoid possible enlarging of the hole inlet as the bit "wobbles" just near the inlet. If I still get enlargement of the hole inlet or outlet, what could be the problem?

I might really be off on this....but, I've noticed that the tubes seem to be looser in the blanks than in the past. I've been buying most of my kits from PSI. I really like that their tubes are already "roughed" up. I've tried different makes of drill bits and it doesn't seem to matter. I have to wonder if the tubes are being made just a micro bit smaller? I use the thick CA glue liberally and that seems to work okay.

If your holes are too large, use a smaller drill bit.

 

[Moosewatcher]

For the really big pens and very expensive blanks, I use the lathe to drill, but for 7,8, and 10mm I use the drill press. I noticed that whenyou bring the brad point bits down to the centerpoint of your X on the blank end, it walks a little bit resulting in off center results at the other end. To counter this, with the drill off, bring the brad point down and prick the blank at the X. If you are satisfied it is center press the bit back into the hole LIGHTLY and turn the drill on. It will travel much straighter through the blank as long as you do not go too fast and clean the flukes out often.

 

[shastastan]

I do get mixed results with the PSI dedicated pen blank chuck. I don't have a Nova chuck, but it sounded interesting so I did some more research. Here's a "how to" the way this guy did it:

Auxiliary Pen Blank Jaws

Fig01 shows why the blank needs to be perfectly square unless you make his jig. Not sure I'm ready to make one yet. I did read some where that another guy used a small hose clamp on the end of the PSI pen blank chuck to try and eliminate any wobble in the chuck. I might just try that. I've had to reassemble my pen chuck because I opened it too far. Not sure If I've got things back to being exactly equally spaced which obviously would affet the hole centering. If I were mass producing, I would probably spring for the Nova Chuck and jaws. I would think that 2 mounting holes per jaw would improve grip stability, too. FWIW

 

[JasonC]

Here's now I set up my drill press - with a Wixey digital gauge that I originally bought for the table saw.

Just stick the gauge on the chuck, zero it, then put it on the table and set the table to 90 degrees.

I also have the Nova Pen Plus jaw set for my Nova chuck.

I initially went from using the drill press to the drilling on the lathe but when I need to drill accurately - like when drilling a 3/4" blank for a pen that usually uses a 7/8" blank - I do it on the drill press.

To hold the blanks on the drill press I cut a couple of 45 degree cuts in some scrap on the table saw then cut the scrap into two "jaws" to sit in a clamp.

Since the jaws I made are square and the notches I cut are perpendicular to the sides of the jaws, I know that my blanks should be held (and drilled) as straight as is possible with my little benchtop drill press.

 

[lwalper]

Agree with some of the above posts. Brad point bits do seem to wander, especially at the beginning of the hole -- the brad seems to catch on the end grain a bit. To overcome som eof that I bring the lathe speed up pretty high so the drill bit actually cuts across the end grain, then reduce the speed to whatever you feel comfortable with for the particular material you're drilling. For me, standard bits actually seem to drill straighter than the brad points.

 

[JasonC]

Agree with some of the above posts. Brad point bits do seem to wander, especially at the beginning of the hole -- the brad seems to catch on the end grain a bit. To overcome som eof that I bring the lathe speed up pretty high so the drill bit actually cuts across the end grain, then reduce the speed to whatever you feel comfortable with for the particular material you're drilling. For me, standard bits actually seem to drill straighter than the brad points.

Agreed on the standard bits.

 

[raar25]

Lots of great stuff but and I am surprised no one mentioned vise flex as an issue. When I started making pens my holes were wondering and one day I noticed if I do not back up the blank against the vise base the vise jaws were flexing. Also using a center drill and standard drill bits gives me a dead on hole every time on the drill press. I have problems on the lathe with chip build up causing my drill to wobble and make the hole oversized so I try to do as much as I can on the drill press and the whole process is faster on the drill press. Also I never use brad points when I have a standard drill.

 

[JasonC]

Lots of great stuff but and I am surprised no one mentioned vise flex as an issue. When I started making pens my holes were wondering and one day I noticed if I do not back up the blank against the vise base the vise jaws were flexing. Also using a center drill and standard drill bits gives me a dead on hole every time on the drill press. I have problems on the lathe with chip build up causing my drill to wobble and make the hole oversized so I try to do as much as I can on the drill press and the whole process is faster on the drill press. Also I never use brad points when I have a standard drill.

I sandwich my blank holders in a basic wood handscrew clamp.

Since I know my table is perpendicular to my chuck and my slots in the blank holders are perpendicular to the table and parallel to the chuck, I just place the blanks between the blank holders, tighten the handscrew clamp, and drill/ream/trim the blanks.

For me, working like this takes some of the variables out of the picture. As far as I know the only variable left is the blank itself - or the actual table of the drill press flexing - but if that happens I think it's time to sharpen the bits. With the blank holders I made I can drill square, rectangular, and round blanks without issue. I'll see how they fare with horn and antler soon enough. I have yet to work with those materials so it'll be a learning experience.

I run the DC with a 2 1/2" hose near the bit while drilling or trimming to keep chips under control and I still double-check to make sure there are no stray chips under the handscrew clamp or blank holders when I switch from one blank to the next.

Often times being a little off center or having the bit wander as you drill won't be an issue but if you're working with segmented blanks and want to carry the design/pattern through the pen properly you HAVE to drill the blank dead nuts - like the slim I attached. If I screwed up drilling that one it'd have been rubbish.

BTW, the reason you see the 82 and 8 degree readings at the top of the Wixey is because it's showing that my floor is at an 8* slope. Makes toolboxes and everything look weird - especially when you hang pictures and such in the shop.

 

[Woodster Will]

Drilling blanks on a drill press is far from ideal as many folks have found out. I've found drilling on the lathe far easier and much more accurate. I turn the blank between centres first then drill it out.