What am I doing wrong?

[Mark Plough]

I've been hanging around for a while now (since Nov 04) and have learned much from the wise people here. The Freedom Pen Project caught my eye on another forum, don/t remember which, and had to check it out. Needles to say I found this little stream fun, friendly, and very inforative, so I joined.

I finaly broke down and bought a Jet mini lathe in late April and started turning pens. I got some corian from Mr. Dolf and have been working making pens from that.

TO my problem. Turning the corian has been a trip. I think the stuff is great. However, I'm having a problem with the assembly of the pens. I have had the corian split. I thought i was applying to much pressure so i backed off on that. Nope, still happens. So I watched as I applied the pressure and it happens before the parts come in contact with the corian. I'm carefull to make sure that thing are lined up straight. Any input folks?http://www.sawmillcreek.org/images/icons/icon5.gif

[Ernie Nyvall]

Mark, I've never turned a pen, but have been reading about it some and just ordered my first kit today.
This may be a goofy idea, but are you getting all the glue out of the tube before you start the assembly? It would seem like the smallest amount of expansion would split corian.
Anyway, thanks for this question. I'll be interested in finding out the answer.

Ernie

[John Hart]

Gee...it almost sounds like your drill is too small...and Ernie might have a point about the glue expansion too...or maybe the glue type. The pieces are a press-fit into the tube and your tube is so tight that even the slightest expansion during the press, is bursting your material. Do your tubes slip in or do you have to apply pressure to get them in?

'Course...I'm hardly an expert on pens...I'm just applying general engineering principles in this analysis.

[Ernie Nyvall]

...and Ernie might have a point about the glue expansion too...

I could have worded that better in my reply, but what I was meaning was that if a too thick of film of CA glue were left in the tube, might that cause too much expansion when the tip is inserted. Same principle, but from the point of the inside of the tube being too small from the thickness of the glue.
Now gorilla glue might cause that glue expansion problem.

Ernie

[Harry Pye]

I tend to agree with Ernie. Are you using a pen mill to square the ends of the blanks after the tubes are glued in? Some people use a disk sander for this and it is OK but it doesn't clean out the inside of the tubes. I got a 25 caliber brass bore cleaning brush from the local gun shop. It is a little tight but wears in very quickly. Just chuck it in your hand drill and clean out the inside of the tubes.

Keeping the glue out in the first place is even easier. Buy some plate wax from Bill Baumbeck or get some from your friendly dentist. This is a sheet of wax and you can press the ends of the tubes into it. That acts like a cookie cutter and the 'cookie' plugs the end of the tube. You can use a slice of potato too.

Hope this helps,

Harry

[Randy Meijer]

I had that happen to me too and I am very careful to have glue-free tubes. Next time I do a Corian pen, I'm going to lightly sand the insides of the tubes so they are not a tight press fit and use a dab of CA glue to be sure the hardware stays in the tubes.

[Randy Meijer]

.....Keeping the glue out in the first place is even easier. Buy some plate wax from Bill Baumbeck or get some from your friendly dentist. This is a sheet of wax and you can press the ends of the tubes into it. That acts like a cookie cutter and the 'cookie' plugs the end of the tube. You can use a slice of potato too.....

I just melt a few candle stubs and pour the wax in waste container of some sort...... a layer about 1/8" thick works like a champ!!

[Dario Octaviano]

Prevention is best but if it still happens, glue inside the tube can be cleaned using a file. I am using my old chainsaw files...works great.

[Harry Goodwin]

I always use the pen mill simply chucked in extra chucks to clean out the glue. Found that a sander works better on cleaning up the blanks on the tubing. My only cracks came when I was out of allignment on the press. I never tried corian. The pen mill is good if you have something out of kilter. You can also clean out the glue with a drill bit from a good collection. Put it in a chuck and turn by hand will work. I'll have to think about the candle wax. The touch of glue sounds good for the parts. Harry

[Mark Plough]

Thanks Guys,

It was indeed the glue. Took one of the cracked pens apart and there it was.
It wasn't much but I guess it was enough.I do use a pen mill but I didn't check to see if I got all the glue. Made 2 pens this afternoon. Used the wax in the tube trick. Works great! Again, thanks.

Markhttp://www.sawmillcreek.org/images/icons/icon14.gif