Rookie problems part one

[Quillpig]

Hi,

We got my son a lathe and some pen turning supplies for Christmas, and we're trying to teach ourselves (with the help of YouTube and this forum). We've run into a few issues and I was hoping for some feedback from the group.

The first issue we ran into was related to gluing the brass tubes into the wooden blanks. We drilled out the blanks with the 7mm bit that came with our kit (from Rockler). The tubes seemed to be a loose fit, so I used plenty of CA glue (again, from the kit) and made sure that the whole tube was well coated, and I stuck it into one side of the hole, swirled it around, and then stuck in in the other side of the hole. We allowed 24 hours for curing. Still, three of the 8 tubes came loose when I used the flush trim bit to even up the end of the blank with the end of the tube.

We re-glued those with 5-minute epoxy, again allowing 24 hours to cure, and one of the three still came loose.

Should the fit be more snug? Are my (cheap) tubes a little too small? Am I using bad glue technique? Is this failure rate par for the course?

I have several other issues, but I'll ask those questions later.

Thanks for all your help!


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[monophoto]

That should not happen!

What is the viscosity of the CA? You should use thick CA to glue in tubes. Frankly, my preference is for polyurethane glue (ie, Gorilla glue) or epoxy rather than CA for gluing tubes.

But another explanation could be that you are getting oversized holes. The tubes should be snug but not tight, but if there is obvious 'wiggle', then the hole is oversized. That could mean that the bit is oversized, or possibly bent, or that you are not drilling straight into the blank.

 

[campzeke]

How are you drilling the blanks? The tube should slide easily into the hole but NO SLOP. I use and recommend epoxy. Thin CA dries too fast and will be absorbed into the wood. Medium or thick CA is ok but ... I like epoxy for its gap filling properties and extended working time. Longer set time but worth it in my opinion.

 

[Gary Beasley]

Your drill press may have an excessive amount of runout causing the hole to be bigger than it should be.
Another thing to try is roughing the brass with sandpaper before glueing to give it more grip.
If the wood is prone to absorbing the glue quickly I like to run some thin ca on the inside and coat it all around. Then a quick cleanup with the drill before glueing the tube in. Have to be quick about seating the tube because the ca will set rather fast with this treatment.
If the wood is a dense oily exotic variety a wash inside with acetone before glueing will help adhesion.

 

[Terredax]

If the hole is too large, that can cause problems.
I too prefer to use epoxy over CA. CA is more brittle and has lower sheer strength. Epoxy can help to fill the over-sized hole.

When milling the ends, be careful not to create heat from the shaft spinning in the tube. That can cause the adhesive to loosen.

I also sand the tubes for better adhesion and wipe the tube with acetone to remove any oils before gluing.

 

[Quillpig]

Thanks for all the quick replies. We drilled the blanks in an old drill press, with the blanks held firmly in a vise. I did sand the tubes to rough them up, and we used a medium viscosity CA glue.

I'll check the runout of the drill press tomorrow, and we will definitely use epoxy or gorilla glue going forward.


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[WriteON]

Welcome to IAP. I never had a problem with CA. I never used epoxy. I only glue with medium CA. There is no reason not to use CA is you choose to do so.
Are the blanks clean... full of dust or dirt. Did you run anything through the tube before gluing. Is the CA fresh? Post some pictures.

 

[Edgar]

Another possibility is heat buildup inside the tube from the sanding mill. Friction inside the the can cause glue failure.

I quit using the mills a couple of years ago. I now use a sanding disk on my headstock & a sanding jig on my tail stock & a cheap set of Harbor Freight punches. No tube friction & no danger of the mill messing up a blank.

For what it's worth, I don't scuff my tubes & I use 2P10 medium CA & let the glue cure at least 24 hours. Works well for me.

 

[wouldentu2?]

Your hole is too big. CA and Epoxy both will adhere a tube even if the hole is a little bigger than the ideal size. You could use the polyurethane Gorilla glue to help you or drill a hole with a smaller drill bit.

 

[Dehn0045]

When things go right for me, I find that the tube is pretty snug in the blank. I use both epoxy and CA, I haven't noticed a big difference, epoxy gives me a longer working time so I feel like I get it more evenly distributed. Also, when using epoxy I push the tube completely thru while twisting and then reapply epoxy and twist while pushing back in. Anyway, for reference 7mm is 0.276" and the standard 7mm tube OD is 0.268", so there is only intended to be about the thickness of a sheet of paper gap between the tube and the blank.

An additional problem that an enlarged hole can cause is weakness of the wood and blowouts while turning. Good glue/epoxy distribution between the tube and the blank will help to avoid this problem.

I've drilled with a handheld drill with acceptable results. Otherwise drilling on the lathe is another option that works well but requires some additional tools.

Best of luck

 

[Gary Beasley]

Ive had drill bits out of true cause the same problem. Roll it across a flat surface to see if its off. Be sure there no nicks on the shaft from over torque that will keep it from seating true as well.

 

[jcm71]

How are you drilling your blanks? Are you using a drill press? How are your pen blanks secured when drilling? Are you're entry holes round or out of round? Need more info from you on your technique and the equipment you are using to drill your blanks. BTW welcome to the forum.

 

[Woodchipper]

Here is a setup I use on my DP. Custom fishing rod builders tried Gorilla glue when it first came on the market but didn't like the expansion of the glue on custom grips- too much to removed when turning the grip. However, it would be an advantage here. Expansion would fill the gaps but you shouldn't have the gaps in the first place. Check your drilling methods and find out what is causing the holes to be oversize. I had this same problem until I changed to the photo setup. I viewed Ed Brown's video on Exotic Blanks about drilling and line up the blank with the drill bit. I secure the blank in the vise (not vice as I have too many of them as it is) and move the vise so the drill bit is on center. Then- drill away!

 

[Quillpig]

I think I've narrowed down the problem to the drill press. It is probably 50 years old, and it getting a bit eccentric

I pulled the chuck and put a dial indicator on the taper, which is about 4-5 thousandths out of round. That gets magnified at the tip of the bit, so my holes are considerably larger than they should be.

My son's solution (did I mention that he's 14) is to spend $1000 of my money and get a new laser-guided drill press. Can anybody suggest a cheaper solution? Is there a chance that my drill press can be put right? I'm doubtful...

Thanks for all the good advice so far, and the welcome.

 

[leehljp]

I think I've narrowed down the problem to the drill press. It is probably 50 years old, and it getting a bit eccentric

I pulled the chuck and put a dial indicator on the taper, which is about 4-5 thousandths out of round. That gets magnified at the tip of the bit, so my holes are considerably larger than they should be.

My son's solution (did I mention that he's 14) is to spend $1000 of my money and get a new laser-guided drill press. Can anybody suggest a cheaper solution? Is there a chance that my drill press can be put right? I'm doubtful...

Thanks for all the good advice so far, and the welcome.

I don't know the average condition of your DP, but some older ones were built to last. If the motor and pulleys are good, it could be a bearing problem. Some bearings on some older models were fairly easy to replace for the mechanical minded (with the right tools). It sounds like that might be the problem.

If looking for a new one, Harbor Freight has some less expensive ones, but be sure no matter which brand you decide on to check for quill travel: 3 inches minimum.

 

[monophoto]

Rather than spending a lot of money on a new drill press, you might want to think about drilling on the lathe. Presumably, your new lathe is properly aligned so that option should be relatively trouble free, but you will need to have some accessories.

By the way, did anyone ever tell you that buying a lathe is only the beginning - and that turning is called a 'vortex' because i pulls money in at an amazing rate?

To drill on the lathe, you will need:
1. A jacobs chuck that fits into the tailstock quill. Jacob's chucks start at about $30, and go up from there depending on the quality and the maximum diameter drill bit they can accommodate. I suggest getting a 1/2" chuck - they make 3/8" chucks but you will soon find yourself wanting to do projects requiring larger bits. You will have a choice between keyed and keyless - keyed are less expensive, and you can tighten a keyed chuck better than you can a keyless chuck. On the other hand, keyless is convenient (there's no chuck key to lose), and potentially safer - if you leave the key in the chuck while drilling, it is possible for the chuck to start spinning in the tailstock and sling the chuck key into your face. My preference is for the keyed variety - I put a larger handle on the key so that I can get more torque, and so that it's harder to misplace.

2. A scroll chuck to hold the blank. They make dedicated pen-drilling chucks, but they are single purpose; a multi-purpose scroll chuck is far more versatile, and you will eventually buy one if you don't already have one. Scroll chucks start at about $90 and go up to three or four times that figure. Less expensive chucks use 'tommy bars' to tighten the chuck, will more expensive models use keys - tommy bar chucks don't get a lot of respect, but for my money, they work just fine.

3. Depending on the chuck you buy and the accessories that come with it, you may or may not need special blank drilling jaws. They make special pen drilling jaws that mount on the scroll chuck and hold the blank at two corners, but they aren't really necessary. If your chuck comes with #1 step jaws, you can mount the blank between centers to turn a tenon on one end, and then mount the blank in the step jaws using that tenon.

Drilling on the lathe involves mounting the blank on the headstock and spinning it at a fairly low speed (usually <500 r/min), and then advancing the stationary drill bit in the Jacobs chuck slowly into the blank. Stop frequently to clear the swarf. If you allow swarf to build up in the drill bit flutes, it will cause friction and heating, and overheating the blank can cause it to crack.. Another reason for going slowly is that in timber with a pronounced grain pattern, the lighter colored wood is softer than the darker wood, and if you try to force the bit into the wood before the tip of the bit cuts a hole, the bit may try to follow the softer wood and can wander off axis. Before drilling, it's wise to check the alignment to make sure that the drill bit in the Jacobs chuck lines up exactly with the axis of the headstock spindle.

 

[gtriever]

I agree with what Louie suggested, that drilling on the lathe is much better (and I have done drilling on the drill press in the past). If all that you're doing is pens, then Penn State's dedicated pen drilling chuck and Jacobs drill chuck are economical buys.

 

[WriteON]

WELCOME to IAP. Ditto to lathe drilling. Less than $150 for the chucks. Buy the larger drill chuck from PSI for $99 and 1/2" jacobs for the tailstock.

 

[Scissortail Pens]

I'll say another +1 to lathe drilling. The only time I go back to drilling on a drill press is when I want to do offset drilling on a blank that has some feature that appears to be on a side that's closer to the edge that I wouldn't be able to get if I drilled in the center.

 

[Dehn0045]

I usually round the blank and then use a collet chuck to hold the rounded blank and drill on the lathe. This also makes it easy to flush trim on the lathe as well (no need for a barrel trimmer). Just mount in the collet chuck and use a skew to make perpendicular cuts until the blank is flush with the brass.

One comment about drilling on the lathe is that you will want to use a slow speed, I have mine at 500rpm. The problem comes if you have a VS lathe, as you slow it down the torque also drops. I have heard of this causing problems. I personally have only ever had a non-VS lathe, so never encountered this, maybe someone that has had problems with this can chime in.

 

[ajollydds]

I'm also new to turning and in my 1st year I've realized that the lathe is the more accurate tool for me for drilling blanks and also for squaring them up.

I also switched to epoxy over CA. a

 

[goldbarron]

I am not sure that this is part of the problem but, how sharp are your tools? And what type of cut is being used scraping or shearing? I am a middle school wood shop teacher and I have students that will blow out 50% of their blanks that I can turn with out any problems. The students apply too much pressure or get a catch and that is all it take to cause a failure.