Advice needed for barrel trimmer/slimline tube failure

[RProctor]

I was squaring down a blank for a slimline and when I brought the trimmer up on the drill press the whole tube came with it and is no stuck on the trimmer. I ordered another but anyone have thoughts on how I can get this off? Also any thoughts on what might have caused it. Was a black inlace acrylester blank that was glue with Tightbond Polyurethane glue the night before and had sit over 12 hours. Tube was scuffed....and I arguably used too much glue not too little. Im pretty sure gluing in a replacement tube I can save the blank it just set me back 3 pens today that needed that trimmer.

 

[RyanS]

I'm not sure what would've caused the failure, but I think some people prefer using a sander and a 90-degree fence to trim barrels down.

 

[RProctor]

I'm not sure what would've caused the failure, but I think some people prefer using a sander and a 90-degree fence to trim barrels down.

And I'm not opposed to that but I currently have no way to do that

 

[PenPal]

I use Gorilla Glue,all blanks are end sanded only needing to be lightly reamed,this before turning. In over 30 yrs I never held a barrel trimmer in a drill press or hand drill. Time is needed to perform the basic essentials especially glue setting. I had a friend though who made and turned thousands of pens routinely for yrs who produced exciting quality pens for a large market. He had drills made to allow a firm fit,no glue. I watched him in awe but then he was a professional,everything he said and did was exciting to watch. All his pens were CA finished.In my workshop there are dedicated units,for example the pen lathe is never dissembled for bowl making etc,the headstock inserts and held in with draw threaded steel. I use two full sets of pin punches to square blanks.Pictures of pens take me 12 minutes taking and placing on the net.

Perhaps a little of this application to making pens is needed to avoid most problems. Have fun I still do my wife and I had our 64th wedding anniversary this last Tuesday,happy wife happy life.

Kind regards Peter.

 

[randyrls]

I brought the trimmer up on the drill press the whole tube came with it and is no stuck on the trimmer. I ordered another but anyone have thoughts on how I can get this off?

It is likely there was glue inside the tube. the spinning pilot of the trimmer softened the glue and it is now stuck to the trimmer. That is likely why the tube came out of the blank too.

Put the trimmer in the drill press. and gently apply heat via a heat gun / hair dryer / torch. Pull the tube off with gloves. Make sure you remove ALL the glue before assembling.

Oh; Last thing; plug the ends of the tube with play dough or dental wax.

 

[donstephan]

Between centers, taper one end of a 1" round bit of maple or similar to fit the morse taper of your headstock spindle. Part off at the narrow end of the taper and insert in the morse taper. Turn off the marks left by the spur drive and true up the face. This is an inexpensive holder for adhesive backed sandpaper. A Jacobs chuck with a morse taper shaft is an almost essential tool for the the lathe if you don't already have one, and a set of transfer punches is about as handy as a pocket on a shirt. With the jacobs chuck in the tailstock, chuck the largest transfer punch that will fit in the brass tube, with the transfer punch point in the chuck to protect it. Slide the glued pen blank on the punch, bring up the tailstock so the punch almost touches the sandpaper, and ease the end of the pen blank onto the sandpaper. A lot of time and sandpaper are saved if the pen body extends beyond the brass tube just a whisker.

Not my invention, recall suggests I learned of this sanding approach on this web site.

 

[Gary Beasley]

The reamer shaft on the trimmer likely was getting the tube hot from friction and if the tube was glued with CA it melted and probably stuck to some glue residue inside. You can quickly release the tube by heating it up gently with a torch. Clean everything up with acetone and wax the shaft of the trimmer.

 

[RProctor]

Tube was glued with poly glue

 

[Woodchipper]

Not quite the same but I "welded" an acrylic blank to the drill bit.

 

[rholiday]

One other thing that can happen is that since there can be a small gap between the trimmer body and the trimmer shaft, the brass tube can get 'extruded' into that small gap and wedge everything together. I think this can only occur with a 7 mm tube. If the blank had been successfully removed, (with tube intact), and put on a mandrel for turning, that bit of 'extruded' brass can wedge itself between the mandrel and the bushing and get the blank stuck on the mandrel.
As to getting the tube released from the trimmer, you might be able to loosen the set screw on the trimmer and try wiggling the shaft or tapping on the shaft to free the tube from the trimmer.

Bob

 

[penicillin]

I use Gorilla Glue (polyurethane) for pens. I always leave them overnight to cure. Here are a few tricks that work for me:

* I use an engineer's depth gauge to measure the tube inside the blank, then mark that depth on the outside of the blank. After that, I trim the blank on the bandsaw, just outside the line. I may use the bandsaw to trim tiny "bites", almost like using the tooth "set" on the blade to "sand off" a tiny bit of the blank to bring it closer to the tube before milling. It is easy, and limits wear on the pen mill.

* On the other side of the blank, where the tube was glued close to the end of the blank, I use a 1/2 inch chisel to scrape off the excess glue on the outside of the blank. Be careful not to cut yourself with the chisel. It helps to clamp the pen blank in a handscrew clamp or a vise. My reasoning for trimming with a chisel is simple: it is easier for me to sharpen chisels than pen mills. Why dull the pen mill on the hardened glue? The real wood is softer.

* I manually insert and twirl the pen mill "drill" into the tube at both ends to knock out any glue "plugs". I manually clean out the tube(s). I tried Play-Doh plugs, but it was messier to clean up Play-Doh than the dried polyurethane glue. I bought some dental wax to try, but keep forgetting to try it.

* If any glue remains in the tube, try cleaning it out by gently twirling a round file inside the tube. It is very rare that I need to do this. (I agree with the others; I think that your mill may be stuck when some of this residual glue melted from friction, then hardened.)

* Next, I square the ends using the pen mill on a small benchtop drill press. I use a handscrew clamp with one screw against the drill press post to keep it from rotating. I insert the blank in the drill, support it with a waste piece underneath, test the up/down motion of the drill press in the blank to make sure it is loose and moves freely before turning on the drill press, and then mill the blank. I am gentle with the drill press, stopping it often to inspect the blank. Stop if you see shiny brass!

* Turn off the drill press, slide the waste piece out, slide the blank off the drill/mill, repeat for the next blank.

 

[KenB259]

I was squaring down a blank for a slimline and when I brought the trimmer up on the drill press the whole tube came with it and is no stuck on the trimmer. I ordered another but anyone have thoughts on how I can get this off? Also any thoughts on what might have caused it. Was a black inlace acrylester blank that was glue with Tightbond Polyurethane glue the night before and had sit over 12 hours. Tube was scuffed....and I arguably used too much glue not too little. Im pretty sure gluing in a replacement tube I can save the blank it just set me back 3 pens today that needed that trimmer.

I still use a pen mill occasionally, never on a segmented blank though. One important thing to look for, before using a pen mill, is to see if the hole looks visually straight. If you are holding the blank by any sort of vice, that hole needs to be straight. You are trying to square the blank to the tube. If you clamp it in a vice, with a hole that is not straight, then you put a mill in there and come straight down, somethings going to give and usually the tube will just spin out. The friction will heat the tube to the point where the glue, any glue, will give out. Some guys use a pen mill without a vice and hold the blank with pliers, especially when they know the hole is crooked. I just sand them , when I am in doubt. I tried the pliers method, didn't work well for me and just felt unsafe. Also, you can usually tell if the hole is crooked by just running the pen mill down through the hole with the drill press off, you shouldn't feel much resistance and if you do it could just be a bit of glue. If that's the case, you should be able to see it in there.


Sent from my iPad using Penturners.org mobile app

 

[Woodchipper]

I insert the pen mill reamer into the tube, line it up with a precision custom triangle and tighten the vise. I would make a short video if I knew how. If there is an excess of wood or blank material, I carefully cut it on the BS to within a couple of mm's of the tube before squaring the blank.