Using lubricant when drilling PR.

[BSea]

I tried this last night when drilling a poly resin pen blank, and it was like night & day to plain drilling. Maybe I've missed this (which is a good possibility), but this worked so much better that I was surprised that I hadn't seen it in several threads & videos about using PR. It cut faster, and much cooler. Normally when drilling PR, I get concerned about blowouts because of the heat build up. But this cut so easily, and just came out the other end perfectly clean on both blank pieces (it's for a cigar). It's not that I wasn't careful & went slow, but usually, I take a break before final drilling of the blank to let the blank & bit cool down. After using the lubricant, I just cleared the bit as normal, but never stopped the lathe till I finished drilling. I also noticed that the blanks were smoother on the inside than the others I've drilled.

So then I began to wonder if there might be a problem using a lubricant with PR. I used a silicon spray lubricant then cleaned the blanks with hot soapy water & q-tips. I haven't painted the inside of the blank yet, and that's the only thing I'm slightly worried about. Unless the paint or glue won't stick, or someone tells me a reason that this shouldn't be done, then this is the method I'm using from now on.

 

[studioso]

Well, silicon is the archenemy of most finishes and glues, but if you say that you washed it with soap, and the walls are smooth, I don't see why this nothing but a great idea.
I'll try it myself next time I drill plastic.

 

[BSea]

I should have pointed out that I soaked the blanks in hot soapy water for about 15 minutes before using the q tips.

 

[Richard Gibson]

I have been using an old candle and run it up and down the turning bit a few times during drilling. Seems to help. At least the squealing that some times occurs. I don't really have any tear outs an the end either.

 

[KenV]

I did not have spray silicone in the shop. Reason is that the stuff gets every where and I have had problems with finishes because of it -- Fish Eye -- is the experienced problem.

The stuff is persistant and does not easily clean off materials.

I do agree that the use of a "cutting fluid" helps with drilling materials, and a super sharp true bit is a good starting point.

I get similar results -- but use machinist bits (higher precision ones that cost a bit more) and a little mineral spirits as needed with acrylics. I tend to treat the bit with cutting wax when drilling M3 or truestone blanks; which does cleanup with soap and water well.


Watch out for the law of unintended consequences with the silicone because you have it all over the area around the drill press.

 

[skiprat]

I use those little spray air travel bottles with water and dishwash liquid. Water is the coolant, soap is the lubricant. No residue left behind to stop glue sticking or ruining finishes ( once dry of course:wink: )
Cheap too !! :biggrin: Just go to the kitchen and both are near the basin.:biggrin:

 

[DurocShark]

I use those little spray air travel bottles with water and dishwash liquid. Water is the coolant, soap is the lubricant. No residue left behind to stop glue sticking or ruining finishes ( once dry of course:wink: )
Cheap too !! :biggrin: Just go to the kitchen and both are near the basin.:biggrin:

I've just recently started doing this. My metal flake blanks have much cleaner holes when I'm done. That means less scrubbing the ridges with acetone to make a smooth paint surface. I suspect my bits will last longer too, as long as I do something to prevent rust afterwards.

 

[BSea]

I use those little spray air travel bottles with water and dishwash liquid. Water is the coolant, soap is the lubricant. No residue left behind to stop glue sticking or ruining finishes ( once dry of course:wink: )
Cheap too !! :biggrin: Just go to the kitchen and both are near the basin.:biggrin:

When I wrote my last post, I kinda slapped my forehead & thought "Dishwashing soap should work, without worrying about contaminating the blank."

Thanks everyone for the suggestions & things to watch out for. I'll be putting the silicone lubricant away. I'm still really amazed that with all the synthetic materials of blanks, that there isn't more mention of using a lubricant when drilling. I have to thank you skiprat for the idea. I got it from watching your video series about turning a steel pen when you used WD-40 to lube the metal. I thought if WD-40 worked for steel, why not silicone for PR?

BTW, the silicone I used was a food grade/electrical grade if that makes any difference to anyone.

 

[DurocShark]

I suspect you don't hear much about it because with slow careful drilling, it's not necessary. Helpful, sure. But the pen drills either way.

I started doing as Skippy does because I had to drill out 50 blanks at once. The bit started getting too hot and I didn't want to wait between blanks to let it cool. This is where using the water/soap solution really helps. If I'm doing one blank, and it's not transparent, I'll probably forgo the soap. Not worth the hassle of cleaning up water on my cast iron lathe bed. (No matter how many rags I lay out, the water STILL gets everywhere.)

 

[KenV]

Water and dishwashing soap are by far the lowest cost and high effective coolants lubricants. I do not use them because of the cleanup associated with them in the clutter of the shop and mess/rust they cause if not cleaned up well.

Mineral spirits evaporate without residue and cutting wax (metal working style) swarf suck up the vacuum/dust collector without problems.

Note that the same/similar discussion is applicable to use of abrasives later in the process (wet sanding give me a better outcome than dry).

(If you have not looked at Russ Fairfield's web site -- I suggest you do. His legacy is a lot of wisdom and experience in writing).

 

[DurocShark]

Hah! Beat you Ken! By seconds!

 

[JimMc7]

I drill blanks on the lathe and had some cracked PR blanks until I started using high speed air from a shop vac to cool the bit. I drill a small amount, remove the bit and hold the vac against the bit. IME, it takes 15-20 seconds to cool the bit and I drill some more. It does take a while to drill using this method but no cracks since I've been using it -- I'm retired so have more time than money so this technique is a good trade for me.

I have used water spray to cool, too, and it worked but I didn't like the water mess on the lathe bed.

Edit to add: drilling on the lathe I don't have to wait for the bit to stop spinning before cooling with the vac. Waiting for the bit to spin down on a drill press might add enough time that the water mess would be worth it.

 

[Dave Turner]

Maybe I've been lucky, but I've never experienced any problems with drilling PR on the lathe, or anything else for that matter. I just pull the drill bit out periodically when it feels like the channels are filled with shavings to clean them out.

I drill everything at 500 - 800 RPM and advance the tailstock at a slow steady pace, trying to get a continuous "string" of shaving coming from the drill (at least until the drill gets deeper in). I've never had a blowout on the far side.

 

[BSea]

I will admit that blowouts are probably relatively rare if people go slow & clean the shavings from their bit. I've had a few at the very end, but I've always allowed a little extra when drilling PR, so far I've only lost one blank to blowout, and that was one of my 1st, and I chalk it up to inexperience. However, the added benefit of smoother interior walls along with faster drilling is benefit enough for me to keep doing something to lubricate the bit when drilling synthetics. Like I mentioned in my 1st post, it was like night & day.

 

[MartinPens]

This is great info. I occasionally have wondered how I might keep the heat down on some of the longer PR blanks, like the Zen, which is a really long way to drill. I don't worry about breakout at the end of the blank because I never drill completely through a blank anymore. I always leave a little room and cut the end off at the band saw table. Thanks for the thread and thanks everyone for all the info.

Regards,

Martin

Sent from my iPad using Forum Runner

 

[skiprat]

Martin, like you said, long Zens and Long Clickers are also my main reason for the lube/coolant. I also use it if I need a particularly 'clean' hole so as not to see the drill marks. Another reason to keep it cool is if the blank isn't much bigger than the final size you want. Just getting warm while drilling, may allow the chuck ( or vise ) to squish a very thin walled warm blank.

'Normally' though, I rarely bother ( lazy :wink

 

[bitshird]

The only material I've had to use any coolant/ lubricant on was some Cebloplast, and I just cooled it with DNA drilled at about 700 RPM an lube, just coolant, I haven't tried any Lucite yet because of the problems I've seen but normally a good drill bit like an OSG or Cleveland Latrobe, well sharpened will do an excellent job. Also Norseman bits are high quality bits as well, I know that the HF 115 drill sets are popular, and cost about the same as 2 or 3 quality drill bits. But why risk a 15.00 or 20.00 blank on a cheap drill bit.

 

[KenV]

"But why risk a 15.00 or 20.00 blank on a cheap drill bit. "

And if your time is worth anything -- most blanks are worth that much pretty fast.


I suspect the answer may be:


Metaphorically -- they see a Yugo as good as a BMW or Lexus

They have not ever used a good or high quality machinist drill bit and do not know the difference.

they like driving a Yugo

They like making cheap work regardless of the amount of effort it takes (also can be called the cheap gene)

They assume that all tools and tooling are made the same -- and when they have problems, it is bad luck.

Precision and consistency are not considered as valuable


They are retired and time has no value


The one that I hope is the valid one -- what I have is what I can afford and I will make do until I can get better.




My observation is that most of those doing the better work have invested a lot of time developing technique/skills to work around the limits of the tools

or they are using better tools to extend the skills and techniques they have.

 

[bitshird]

Ken, there's also a line that reads
"tis a poor craftsman that blames his tools for his shoddy work"

 

[BSea]

Ok, I tried a little experiment. This whole thread is kinda a result of me trying to drill out a blank turned down to 1/2". I had to do that because I basically cut down a round 1 1/2" bottle stopper into 3rds. The reason why is a different story. Anyway, I drill on the lathe, and only have the basic collets that came with the collet chuck. 5/8ths was too big for the blank, so I had to go all the way to 1/2. I tried drilling the 1st blank last night, and got 75% completed when it got too hot & basically melted. That happened really fast too. So I still wanted to accomplish something last night, so I turned another regular sized blank. This is the one I used the lubricant on. That's why I started this thread this morning.

So after lunch today, I decided to try another 1/2" blank using soapy water as the lubricant. Here are some pictures of the results

The 1st shows the pen starting to be drilled. It's about 1/2 in at this point. BTW, it's for a sierra. If you are wondering about the tool rest being positioned there, it's just to help guide the bit. I've found this helps get the bit started online. I removed it before continuing to drill

The 2nd picture shows the blank (bottom) drilled out deep enough for a sierra tube + about 1/4" extra. I know it's hard to see, but it you look at the right side of the blank, you can see a line where the color changes. This is the depth of the drilling. The other blank (top) was my 1st attempt. I thought I would play with some colors to see how a finished pen might look like. And if anybody is curious, it's a Pua Shell blank from brooks803.

And KenV is right. A good drill bit goes a long way in making things easier. I've been upgrading my bits 1 or 2 at a time. This is not one of them. It's one thing to use general purpose bits for . . . Well . . . .general use. But I can sure see a difference when I use one of my better bits for drill blanks.

 

[jttheclockman]

I am a huge fan of using denatured alcohol. It works great for me.

I not only use it to drill pen blanks but also when I am drilling billiard ball clocks. They too a re aform of hard acrylic and alot harder than the pen blanks.

 

[Timebandit]

Bob i know this is off topic, but it looks like you collet isnt seated all the way in you collet chuck. The collet needs to be seated all the way to the front off the chuck to be as precise as possible. JohnnyCNC has a video about how to make sure that you collet is seated all the way to the front of the chuck before screwing it on.

Sorry for being off topic,but this could be throwing your drilling off as well.

Justin

 

[BSea]

Bob i know this is off topic, but it looks like you collet isnt seated all the way in you collet chuck. The collet needs to be seated all the way to the front off the chuck to be as precise as possible. JohnnyCNC has a video about how to make sure that you collet is seated all the way to the front of the chuck before screwing it on.

Sorry for being off topic,but this could be throwing your drilling off as well.

Justin

I just watched he video & went outside to look at my collet chuck. I think you're right, I was doing it wrong. Thanks for the tip.:redface: I'd watched his videos a long time ago before I actually started turning pens, but I don't remember this one.

I will admit I was doing this blank a little different because it was so thin. I would stop & pull the blank out, so the collet wasn't being compressed on a section that had been drilled. That's one of the reasons the blank was left so long. But that doesn't have anything to do with your tip.

 

[Wildman]

I tried drilling using water as coolant but stopped that practice because of the mess.

For both wood and acrylic blanks back out frequently and use a shop-van for chip removal. Drilling less than a ¼" and backing out the drill bit takes longer but do not get blow outs or holes that are caddy-umpus.

Works for me!