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View Full Version : Newbie in need of some advice...



steiner1000
6th September 2008, 03:02 PM
Any advice would be much appreciated. I have been turning for about 3 months and am kind of addicted to it now. But, I am running into a problem... here is what happens.

I glue the tube into the pen blank
I use a barrel trimmer to square the ends (which I double check)
I turn, sand and finish the blank
Then when I go to assemble it, one of the tubes is protruding slightly from the blank...
I then have to trim it again hoping to get it flush.

I do not understand why this happens... again any advice would be much appreciated.

Thanks,
Chad

PenmanWA
6th September 2008, 03:31 PM
ive been turning about the same length of time and have come across the same problem a few times. I found that it is because the tubes arent glued properly and when you try and asemble the tubes have slipped a bit. Happens to me mainly when im turning acrylic blanks.

Hope this helps
Brett

corbs
6th September 2008, 03:47 PM
If its happening with acrylic blanks (and to a lesser extent wood) you could be generating too much heat in the sanding process and shrinking the blank on the tube. With acrylic blanks I dry sand to 400 then wet sand to 12000 with acrylic pads or micro mesh.

Corbs

regulated
6th September 2008, 09:00 PM
I agree with corbs. This has happened to me as well, especially with acrylic blanks. I will happen sometimes with wood if the blank is not glued and secured into the mandrel correctly.

BJ

NewLondon88
6th September 2008, 10:10 PM
I agree with the two above.. heat.

Not only happens with acrylics, but with any wood not completely dried out. The moisture is lost especially during sanding, which generates a surprising amount of heat, and the wood shrinks back to reveal the tube. Also, as it cools, you may find small cracks developing as it shrinks. I went through this after cutting up a large (and expensive!) chunk of amboyna. After about two weeks, every pen cracked and most were pulling away from the findings. More glue didn't help much.

Wet sanding might help, as will sanding slower and allowing the blank to cool if it starts to get too warm. Hard to do when this is all new, since you're ALMOST DONE!! But really .. walk away for a minute and come back.Especially hard when it is a new wood and you just can't wait to see the finished pen..:p

steiner1000
7th September 2008, 01:51 AM
Thanks for the advice... Now that you guys mention it, it is only happening with the acrylic blanks. I will try your advice and let you know. Thank you very much everyone.

Chad

Simomatra
7th September 2008, 08:55 AM
Must agree as well that heat is the problem shrinking the blank away from the tube

PenmanWA
7th September 2008, 01:59 PM
Thanks for the tips, i never thought about wet sanding the acrylics. Ill try it next time i get some. then ill post some pics of the finished pens.

Sawdust Maker
7th September 2008, 09:11 PM
gees
I have one acrylic blank. I pick it up, look at it, shake my head and put it back.
there's soooo much nice wood just begging to be drilled, glued and penned :!

In fact why am I here typing this drivel?
Oh fathers day - red wine - shouldn't play with spinning wood :no::no:

steiner1000
8th September 2008, 03:59 PM
If heat is causing the problem, what type of polish would you put on the turned pen? All of the finishes that I have are friction finishes... which of course make heat? Thanks.

By the way, I did turn another acrylic and sanded it much lighter and took brakes and it did seem to help, but still had the slightest of issues.

Once the blank shrinks and I fix it, is the pen still usable if assembled. Thanks again.

Chad

corbs
8th September 2008, 07:28 PM
The heat generated by the polish shouldn't be enough to cause issues, I use a water based glass polish but others use Maguires Plastix Polish which you should be able to get from auto pro (or similar). With slimlines there is a fair fudge factor in the tube length but some other kits are less forgiving:-. What sort of issues did you have this time around?

regulated
8th September 2008, 08:11 PM
I believe the heat is actually caused when turning the pen, not sanding. Quite a bit of pressure is place on those little bushes.

When sanding its nice and easy to use soaked wet and dry. If it starts looking like a paste wet the sandpaper again and keep going. You'll get a much cleaner surface then. I don't use water with the polish. I use meguires swirl remover and it seems to be fine.

BJ

madcraft
24th April 2009, 06:56 PM
I used to have a similar problem when trimming . {the CA would let go} I figured out I was pushing the tube straight in and not twisting and I was using thin CA so the coverage was not enough { the thin CA was leaching away into the wood before it could grab} , since I started using med to thick and did the twisty thing no problems


I haven't done Acrylic so I cant comment but I can't see there being much difference